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• DRY and SRP

  - by Timothy Klenke

  Originally posted on: http://geekswithblogs.net/TimothyK/archive/2014/06/11/dry-and-srp.aspxKent Beck’s XP Simplicity Rules (aka Four Rules of Simple Design) are a prioritized list of rules that when applied to your code generally yield a great design.  As you’ll see from the above link the list has slightly evolved over time.  I find today they are usually listed as: All Tests Pass Don’t Repeat Yourself (DRY) Express Intent Minimalistic These are prioritized.  If your code doesn’t work (rule 1) then everything else is forfeit.  Go back to rule one and get the code working before worrying about anything else. Over the years the community have debated whether the priority of rules 2 and 3 should be reversed.  Some say a little duplication in the code is OK as long as it helps express intent.  I’ve debated it myself.  This recent post got me thinking about this again, hence this post.   I don’t think it is fair to compare “Expressing Intent” against “DRY”.  This is a comparison of apples to oranges.  “Expressing Intent” is a principal of code quality.  “Repeating Yourself” is a code smell.  A code smell is merely an indicator that there might be something wrong with the code.  It takes further investigation to determine if a violation of an underlying principal of code quality has actually occurred. For example “using nouns for method names”, “using verbs for property names”, or “using Booleans for parameters” are all code smells that indicate that code probably isn’t doing a good job at expressing intent.  They are usually very good indicators.  But what principle is the code smell of Duplication pointing to and how good of an indicator is it? Duplication in the code base is bad for a couple reasons.  If you need to make a change and that needs to be made in a number of locations it is difficult to know if you have caught all of them.  This can lead to bugs if/when one of those locations is overlooked.  By refactoring the code to remove all duplication there will be left with only one place to change, thereby eliminating this problem. With most projects the code becomes the single source of truth for a project.  If a production code base is inconsistent with a five year old requirements or design document the production code that people are currently living with is usually declared as the current reality (or truth).  Requirement or design documents at this age in a project life cycle are usually of little value. Although comparing production code to external documentation is usually straight forward, duplication within the code base muddles this declaration of truth.  When code is duplicated small discrepancies will creep in between the two copies over time.  The question then becomes which copy is correct?  As different factions debate how the software should work, trust in the software and the team behind it erodes. The code smell of Duplication points to a violation of the “Single Source of Truth” principle.  Let me define that as: A stakeholder’s requirement for a software change should never cause more than one class to change. Violation of the Single Source of Truth principle will always result in duplication in the code.  However, the inverse is not always true.  Duplication in the code does not necessarily indicate that there is a violation of the Single Source of Truth principle. To illustrate this, let’s look at a retail system where the system will (1) send a transaction to a bank and (2) print a receipt for the customer.  Although these are two separate features of the system, they are closely related.  The reason for printing the receipt is usually to provide an audit trail back to the bank transaction.  Both features use the same data:  amount charged, account number, transaction date, customer name, retail store name, and etcetera.  Because both features use much of the same data, there is likely to be a lot of duplication between them.  This duplication can be removed by making both features use the same data access layer. Then start coming the divergent requirements.  The receipt stakeholder wants a change so that the account number has the last few digits masked out to protect the customer’s privacy.  That can be solve with a small IF statement whilst still eliminating all duplication in the system.  Then the bank wants to take a picture of the customer as well as capture their signature and/or PIN number for enhanced security.  Then the receipt owner wants to pull data from a completely different system to report the customer’s loyalty program point total. After a while you realize that the two stakeholders have somewhat similar, but ultimately different responsibilities.  They have their own reasons for pulling the data access layer in different directions.  Then it dawns on you, the Single Responsibility Principle: There should never be more than one reason for a class to change. In this example we have two stakeholders giving two separate reasons for the data access class to change.  It is clear violation of the Single Responsibility Principle.  That’s a problem because it can often lead the project owner pitting the two stakeholders against each other in a vein attempt to get them to work out a mutual single source of truth.  But that doesn’t exist.  There are two completely valid truths that the developers need to support.  How is this to be supported and honour the Single Responsibility Principle?  The solution is to duplicate the data access layer and let each stakeholder control their own copy. The Single Source of Truth and Single Responsibility Principles are very closely related.  SST tells you when to remove duplication; SRP tells you when to introduce it.  They may seem to be fighting each other, but really they are not.  The key is to clearly identify the different responsibilities (or sources of truth) over a system.  Sometimes there is a single person with that responsibility, other times there are many.  This can be especially difficult if the same person has dual responsibilities.  They might not even realize they are wearing multiple hats. In my opinion Single Source of Truth should be listed as the second rule of simple design with Express Intent at number three.  Investigation of the DRY code smell should yield to the proper application SST, without violating SRP.  When necessary leave duplication in the system and let the class names express the different people that are responsible for controlling them.  Knowing all the people with responsibilities over a system is the higher priority because you’ll need to know this before you can express it.  Although it may be a code smell when there is duplication in the code, it does not necessarily mean that the coder has chosen to be expressive over DRY or that the code is bad.

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• Expectations + Rewards = Innovation

  - by D'Arcy Lussier

  “Innovation” is a heavy word. We regard those that embrace it as “Innovators”. We describe organizations as being “Innovative”. We hold those associated with the word in high regard, even though its dictionary definition is very simple: Introducing something new. What our culture has done is wrapped Innovation in white robes and a gold crown. Innovation is rarely just introducing something new. Innovations and innovators are typically associated with other terms: groundbreaking, genius, industry-changing, creative, leading. Being a true innovator and creating innovations are a big deal, and something companies try to strive for…or at least say they strive for. There’s huge value in being recognized as an innovator in an industry, since the idea is that innovation equates to increased profitability. IBM ran an ad a few years back that showed what their view of innovation is: “The point of innovation is to make actual money.” If the money aspect makes you feel uneasy, consider it another way: the point of innovation is to <insert payoff here>. Companies that innovate will be more successful. Non-profits that innovate can better serve their target clients. Governments that innovate can better provide services to their citizens. True innovation is not easy to come by though. As with anything in business, how well an organization will innovate is reliant on the employees it retains, the expectations placed on those employees, and the rewards available to them. In a previous blog post I talked about one formula: Right Employees + Happy Employees = Productive Employees I want to introduce a new one, that builds upon the previous one: Expectations + Rewards = Innovation  The level of innovation your organization will realize is directly associated with the expectations you place on your staff and the rewards you make available to them. Expectations We may feel uncomfortable with the idea of placing expectations on our staff, mainly because expectation has somewhat of a negative or cold connotation to it: “I expect you to act this way or else!” The problem is in the or-else part…we focus on the negative aspects of failing to meet expectations instead of looking at the positive side. “I expect you to act this way because it will produce <insert benefit here>”. Expectations should not be set to punish but instead be set to ensure quality. At a recent conference I spoke with some Microsoft employees who told me that you have five years from starting with the company to reach a “Senior” level. If you don’t, then you’re let go. The expectation Microsoft placed on their staff is that they should be working towards improving themselves, taking more responsibility, and thus ensure that there is a constant level of quality in the workforce. Rewards Let me be clear: a paycheck is not a reward. A paycheck is simply the employer’s responsibility in the employee/employer relationship. A paycheck will never be the key motivator to drive innovation. Offering employees something over and above their required compensation can spur them to greater performance and achievement. Working in the food service industry, this tactic was used again and again: whoever has the highest sales over lunch will receive a free lunch/gift certificate/entry into a draw/etc. There was something to strive for, to try beyond the baseline of what our serving jobs were. It was through this that innovative sales techniques would be tried and honed, with key servers being top sellers time and time again. At a code camp I spoke at, I was amazed to see that all the employees from one company receive $100 Visa gift cards as a thank you for taking time to speak. Again, offering something over and above that can give that extra push for employees. Rewards work. But what about the fairness angle? In the restaurant example I gave, there were servers that would never win the competition. They just weren’t good enough at selling and never seemed to get better. So should those that did work at performing better and produce more sales for the restaurant not get rewarded because those who weren’t working at performing better might get upset? Of course not! Organizations succeed because of their top performers and those that strive to join their ranks. The Expectation/Reward Graph While the Expectations + Rewards = Innovation formula may seem like a simple mathematics formula, there’s much more going under the hood. In fact there are three different outcomes that could occur based on what you put in as values for Expectations and Rewards. Consider the graph below and the descriptions that follow: Disgruntled – High Expectation, Low Reward I worked at a company where the mantra was “Company First, Because We Pay You”. Even today I still hear stories of how this sentiment continues to be perpetuated: They provide you a paycheck and a means to live, therefore you should always put them as your top priority. Of course, this is a huge imbalance in the expectation/reward equation. Why would anyone willingly meet high expectations of availability, workload, deadlines, etc. when there is no reward other than a paycheck to show for it? Remember: paychecks are not rewards! Instead, you see employees be disgruntled which not only affects the level of production but also the level of quality within an organization. It also means that you see higher turnover. Complacent – Low Expectation, Low Reward Complacency is a systemic problem that typically exists throughout all levels of an organization. With no real expectations or rewards, nobody needs to excel. In fact, those that do try to innovate, improve, or introduce new things into the organization might be shunned or pushed out by the rest of the staff who are just doing things the same way they’ve always done it. The bigger issue for the organization with low/low values is that at best they’ll never grow beyond their current size (and may shrink actually), and at worst will cease to exist. Entitled – Low Expectation, High Reward It’s one thing to say you have the best people and reward them as such, but its another thing to actually have the best people and reward them as such. Organizations with Entitled employees are the former: their organization provides them with all types of comforts, benefits, and perks. But there’s no requirement before the rewards are dolled out, and there’s no short-list of who receives the rewards. Everyone in the company is treated the same and is given equal share of the spoils. Entitlement is actually almost identical with Complacency with one notable difference: just try to introduce higher expectations into an entitled organization! Entitled employees have been spoiled for so long that they can’t fathom having rewards taken from them, or having to achieve specific levels of performance before attaining them. Those running the organization also buy in to the Entitled sentiment, feeling that they must persist the same level of comforts to appease their staff…even though the quality of the employee pool may be suspect. Innovative – High Expectation, High Reward Finally we have the Innovative organization which places high expectations but also provides high rewards. This organization gets it: if you truly want the best employees you need to apply equal doses of pressure and praise. Realize that I’m not suggesting crazy overtime or un-realistic working conditions. I do not agree with the “Glengary-Glenross” method of encouragement. But as anyone who follows sports can tell you, the teams that win are the ones where the coaches push their players to be their best; to achieve new levels of performance that they didn’t know they could receive. And the result for the players is more money, fame, and opportunity. It’s in this environment that organizations can focus on innovation – true innovation that builds the business and allows everyone involved to truly benefit. In Closing Organizations love to use the word “Innovation” and its derivatives, but very few actually do innovate. For many, the term has just become another marketing buzzword to lump in with all the other business terms that get overused. But for those organizations that truly get the value of innovation, they will be the ones surging forward while other companies simply fade into the background. And they will be the organizations that expect more from their employees, and give them their just rewards.

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• Securing WebSocket applications on Glassfish

  - by Pavel Bucek

  Today we are going to cover deploying secured WebSocket applications on Glassfish and access to these services using WebSocket Client API. WebSocket server application setup Our server endpoint might look as simple as this: @ServerEndpoint("/echo") public class EchoEndpoint { @OnMessage   public String echo(String message) {     return message + " (from your server)";   } } Everything else must be configured on container level. We can start with enabling SSL, which will require web.xml to be added to your project. For starters, it might look as following: <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee">   <security-constraint>     <web-resource-collection>       <web-resource-name>Protected resource</web-resource-name>       <url-pattern>/*</url-pattern>       <http-method>GET</http-method>     </web-resource-collection>     <!-- https -->     <user-data-constraint>       <transport-guarantee>CONFIDENTIAL</transport-guarantee>     </user-data-constraint>   </security-constraint> </web-app> This is minimal web.xml for this task - web-resource-collection just defines URL pattern and HTTP method(s) we want to put a constraint on and user-data-constraint defines that constraint, which is in our case transport-guarantee. More information about these properties and security settings for web application can be found in Oracle Java EE 7 Tutorial. I have some simple webpage attached as well, so I can test my endpoint right away. You can find it (along with complete project) in Tyrus workspace: [webpage] [whole project]. After deploying this application to Glassfish Application Server, you should be able to hit it using your favorite browser. URL where my application resides is https://localhost:8181/sample-echo-https/ (may be different, depends on other configuration). My browser warns me about untrusted certificate (I use what freshly built Glassfish provides - self signed certificates) and after adding an exception for this site, I can see my webpage and I am able to securely connect to wss://localhost:8181/sample-echo-https/echo. WebSocket client Already mentioned demo application also contains test client, but execution of this is skipped for normal build. Reason for this is that Glassfish uses these self-signed "random" untrusted certificates and you are (in most cases) not able to connect to these services without any additional settings. Creating test WebSocket client is actually quite similar to server side, only difference is that you have to somewhere create client container and invoke connect with some additional info. Java API for WebSocket allows you to use annotated and programmatic way to construct endpoints. Server side shows the annotated case, so let's see how the programmatic approach will look. final WebSocketContainer client = ContainerProvider.getWebSocketContainer(); client.connectToServer(new Endpoint() {   @Override   public void onOpen(Session session, EndpointConfig EndpointConfig) {     try {       // register message handler - will just print out the       // received message on standard output.       session.addMessageHandler(new MessageHandler.Whole<String>() {       @Override         public void onMessage(String message) {          System.out.println("### Received: " + message);         }       });       // send a message       session.getBasicRemote().sendText("Do or do not, there is no try.");     } catch (IOException e) {       // do nothing     }   } }, ClientEndpointConfig.Builder.create().build(),    URI.create("wss://localhost:8181/sample-echo-https/echo")); This client should work with some secured endpoint with valid certificated signed by some trusted certificate authority (you can try that with wss://echo.websocket.org). Accessing our Glassfish instance will require some additional settings. You can tell Java which certificated you trust by adding -Djavax.net.ssl.trustStore property (and few others in case you are using linked sample). Complete command line when you are testing your service might need to look somewhat like: mvn clean test -Djavax.net.ssl.trustStore=$AS_MAIN/domains/domain1/config/cacerts.jks\ -Djavax.net.ssl.trustStorePassword=changeit -Dtyrus.test.host=localhost\ -DskipTests=false Where AS_MAIN points to your Glassfish instance. Note: you might need to setup keyStore and trustStore per client instead of per JVM; there is a way how to do it, but it is Tyrus proprietary feature: http://tyrus.java.net/documentation/1.2.1/user-guide.html#d0e1128. And that's it! Now nobody is able to "hear" what you are sending to or receiving from your WebSocket endpoint. There is always room for improvement, so the next step you might want to take is introduce some authentication mechanism (like HTTP Basic or Digest). This topic is more about container configuration so I'm not going to go into details, but there is one thing worth mentioning: to access services which require authorization, you might need to put this additional information to HTTP headers of first (Upgrade) request (there is not (yet) any direct support even for these fundamental mechanisms, user need to register Configurator and add headers in beforeRequest method invocation). I filed related feature request as TYRUS-228; feel free to comment/vote if you need this functionality.

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• Unlocking Productivity

  - by Michael Snow

  Unlocking Productivity in Life Sciences with Consolidated Content Management by Joe Golemba, Vice President, Product Management, Oracle WebCenter As life sciences organizations look to become more operationally efficient, the ability to effectively leverage information is a competitive advantage. Whether data mining at the drug discovery phase or prepping the sales team before a product launch, content management can play a key role in developing, organizing, and disseminating vital information. The goal of content management is relatively straightforward: put the information that people need where they can find it. A number of issues can complicate this; information sits in many different systems, each of those systems has its own security, and the information in those systems exists in many different formats. Identifying and extracting pertinent information from mountains of farflung data is no simple job, but the alternative—wasted effort or even regulatory compliance issues—is worse. An integrated information architecture can enable health sciences organizations to make better decisions, accelerate clinical operations, and be more competitive. Unstructured data matters Often when we think of drug development data, we think of structured data that fits neatly into one or more research databases. But structured data is often directly supported by unstructured data such as experimental protocols, reaction conditions, lot numbers, run times, analyses, and research notes. As life sciences companies seek integrated views of data, they are typically finding diverse islands of data that seemingly have no relationship to other data in the organization. Information like sales reports or call center reports can be locked into siloed systems, and unavailable to the discovery process. Additionally, in the increasingly networked clinical environment, Web pages, instant messages, videos, scientific imaging, sales and marketing data, collaborative workspaces, and predictive modeling data are likely to be present within an organization, and each source potentially possesses information that can help to better inform specific efforts. Historically, content management solutions that had 21CFR Part 11 capabilities—electronic records and signatures—were focused mainly on content-enabling manufacturing-related processes. Today, life sciences companies have many standalone repositories, requiring different skills, service level agreements, and vendor support costs to manage them. With the amount of content doubling every three to six months, companies have recognized the need to manage unstructured content from the beginning, in order to increase employee productivity and operational efficiency. Using scalable and secure enterprise content management (ECM) solutions, organizations can better manage their unstructured content. These solutions can also be integrated with enterprise resource planning (ERP) systems or research systems, making content available immediately, in the context of the application and within the flow of the employee’s typical business activity. Administrative safeguards—such as content de-duplication—can also be applied within ECM systems, so documents are never recreated, eliminating redundant efforts, ensuring one source of truth, and maintaining content standards in the organization. Putting it in context Consolidating structured and unstructured information in a single system can greatly simplify access to relevant information when it is needed through contextual search. Using contextual filters, results can include therapeutic area, position in the value chain, semantic commonalities, technology-specific factors, specific researchers involved, or potential business impact. The use of taxonomies is essential to organizing information and enabling contextual searches. Taxonomy solutions are composed of a hierarchical tree that defines the relationship between different life science terms. When overlaid with additional indexing related to research and/or business processes, it becomes possible to effectively narrow down the amount of data that is returned during searches, as well as prioritize results based on specific criteria and/or prior search history. Thus, search results are more accurate and relevant to an employee’s day-to-day work. For example, a search for the word "tissue" by a lab researcher would return significantly different results than a search for the same word performed by someone in procurement. Of course, diverse data repositories, combined with the immense amounts of data present in an organization, necessitate that the data elements be regularly indexed and cached beforehand to enable reasonable search response times. In its simplest form, indexing of a single, consolidated data warehouse can be expected to be a relatively straightforward effort. However, organizations require the ability to index multiple data repositories, enabling a single search to reference multiple data sources and provide an integrated results listing. Security and compliance Beyond yielding efficiencies and supporting new insight, an enterprise search environment can support important security considerations as well as compliance initiatives. For example, the systems enable organizations to retain the relevance and the security of the indexed systems, so users can only see the results to which they are granted access. This is especially important as life sciences companies are working in an increasingly networked environment and need to provide secure, role-based access to information across multiple partners. Although not officially required by the 21 CFR Part 11 regulation, the U.S. Food and Drug Administraiton has begun to extend the type of content considered when performing relevant audits and discoveries. Having an ECM infrastructure that provides centralized management of all content enterprise-wide—with the ability to consistently apply records and retention policies along with the appropriate controls, validations, audit trails, and electronic signatures—is becoming increasingly critical for life sciences companies. Making the move Creating an enterprise-wide ECM environment requires moving large amounts of content into a single enterprise repository, a daunting and risk-laden initiative. The first key is to focus on data taxonomy, allowing content to be mapped across systems. The second is to take advantage new tools which can dramatically speed and reduce the cost of the data migration process through automation. Additional content need not be frozen while it is migrated, enabling productivity throughout the process. The ability to effectively leverage information into success has been gaining importance in the life sciences industry for years. The rapid adoption of enterprise content management, both in operational processes as well as in scientific management, are clear indicators that the companies are looking to use all available data to be better informed, improve decision making, minimize risk, and increase time to market, to maintain profitability and be more competitive. As more and more varieties and sources of information are brought under the strategic management umbrella, the ability to divine knowledge from the vast pool of information is increasingly difficult. Simple search engines and basic content management are increasingly unable to effectively extract the right information from the mountains of data available. By bringing these tools into context and integrating them with business processes and applications, we can effectively focus on the right decisions that make our organizations more profitable. More Information Oracle will be exhibiting at DIA 2012 in Philadelphia on June 25-27. Stop by our booth Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} (#2825) to learn more about the advantages of a centralized ECM strategy and see the Oracle WebCenter Content solution, our 21 CFR Part 11 compliant content management platform.

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• Combining Shared Secret and Username Token – Azure Service Bus

  - by Michael Stephenson

  As discussed in the introduction article this walkthrough will explain how you can implement WCF security with the Windows Azure Service Bus to ensure that you can protect your endpoint in the cloud with a shared secret but also flow through a username token so that in your listening WCF service you will be able to identify who sent the message. This could either be in the form of an application or a user depending on how you want to use your token. Prerequisites Before going into the walk through I want to explain a few assumptions about the scenario we are implementing but to keep the article shorter I am not going to walk through all of the steps in how to setup some of this. In the solution we have a simple console application which will represent the client application. There is also the services WCF application which contains the WCF service we will expose via the Windows Azure Service Bus. The WCF Service application in this example was hosted in IIS 7 on Windows 2008 R2 with AppFabric Server installed and configured to auto-start the WCF listening services. I am not going to go through significant detail around the IIS setup because it should not matter in relation to this article however if you want to understand more about how to configure WCF and IIS for such a scenario please refer to the following paper which goes into a lot of detail about how to configure this. The link is: http://tinyurl.com/8s5nwrz   The Service Component To begin with let's look at the service component and how it can be configured to listen to the service bus using a shared secret but to also accept a username token from the client. In the sample the service component is called Acme.Azure.ServiceBus.Poc.UN.Services. It has a single service which is the Visual Studio template for a WCF service when you add a new WCF Service Application so we have a service called Service1 with its Echo method. Nothing special so far!.... The next step is to look at the web.config file to see how we have configured the WCF service. In the services section of the WCF configuration you can see I have created my service and I have created a local endpoint which I simply used to do a little bit of diagnostics and to check it was working, but more importantly there is the Windows Azure endpoint which is using the ws2007HttpRelayBinding (note that this should also work just the same if your using netTcpRelayBinding). The key points to note on the above picture are the service behavior called MyServiceBehaviour and the service bus endpoints behavior called MyEndpointBehaviour. We will go into these in more detail later.   The Relay Binding The relay binding for the service has been configured to use the TransportWithMessageCredential security mode. This is the important bit where the transport security really relates to the interaction between the service and listening to the Azure Service Bus and the message credential is where we will use our username token like we have specified in the message/clientCrentialType attribute. Note also that we have left the relayClientAuthenticationType set to RelayAccessToken. This means that authentication will be made against ACS for accessing the service bus and messages will not be accepted from any sender who has not been authenticated by ACS.   The Endpoint Behaviour In the below picture you can see the endpoint behavior which is configured to use the shared secret client credential for accessing the service bus and also for diagnostic purposes I have included the service registry element. Hopefully if you are familiar with using Windows Azure Service Bus relay feature the above is very familiar to you and this is a very common setup for this section. There is nothing specific to the username token implementation here. The Service Behaviour Now we come to the bit with most of the username token bits in it. When you configure the service behavior I have included the serviceCredentials element and then setup to use userNameAuthentication and you can see that I have created my own custom username token validator.   This setup means that WCF will hand off to my class for validating the username token details. I have also added the serviceSecurityAudit element to give me a simple auditing of access capability. My UsernamePassword Validator The below picture shows you the details of the username password validator class I have implemented. WCF will hand off to this class when validating the token and give me a nice way to check the token credentials against an on-premise store. You have all of the validation features with a non-service bus WCF implementation available such as validating the username password against active directory or ASP.net membership features or as in my case above something much simpler.   The Client Now let's take a look at the client side of this solution and how we can configure the client to authenticate against ACS but also send a username token over to the service component so it can implement additional security checks on-premise. I have a console application and in the program class I want to use the proxy generated with Add Service Reference to send a message via the Azure Service Bus. You can see in my WCF client configuration below I have setup my details for the azure service bus url and am using the ws2007HttpRelayBinding. Next is my configuration for the relay binding. You can see below I have configured security to use TransportWithMessageCredential so we will flow the username token with the message and also the RelayAccessToken relayClientAuthenticationType which means the component will validate against ACS before being allowed to access the relay endpoint to send a message.     After the binding we need to configure the endpoint behavior like in the below picture. This is the normal configuration to use a shared secret for accessing a Service Bus endpoint.   Finally below we have the code of the client in the console application which will call the service bus. You can see that we have created our proxy and then made a normal call to a WCF service but this time we have also set the ClientCredentials to use the appropriate username and password which will be flown through the service bus and to our service which will validate them.     Conclusion As you can see from the above walkthrough it is not too difficult to configure a service to use both a shared secret and username token at the same time. This gives you the power and protection offered by the access control service in the cloud but also the ability to flow additional tokens to the on-premise component for additional security features to be implemented. Sample The sample used in this post is available at the following location: https://s3.amazonaws.com/CSCBlogSamples/Acme.Azure.ServiceBus.Poc.UN.zip

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• Diving into OpenStack Network Architecture - Part 2 - Basic Use Cases

  - by Ronen Kofman

    rkofman Normal rkofman 4 138 2014-06-05T03:38:00Z 2014-06-05T05:04:00Z 3 2735 15596 Oracle Corporation 129 36 18295 12.00 Clean Clean false false false false EN-US X-NONE HE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi; mso-bidi-language:AR-SA;} In the previous post we reviewed several network components including Open vSwitch, Network Namespaces, Linux Bridges and veth pairs. In this post we will take three simple use cases and see how those basic components come together to create a complete SDN solution in OpenStack. With those three use cases we will review almost the entire network setup and see how all the pieces work together. The use cases we will use are: 1.       Create network – what happens when we create network and how can we create multiple isolated networks 2.       Launch a VM – once we have networks we can launch VMs and connect them to networks. 3.       DHCP request from a VM – OpenStack can automatically assign IP addresses to VMs. This is done through local DHCP service controlled by OpenStack Neutron. We will see how this service runs and how does a DHCP request and response look like. In this post we will show connectivity, we will see how packets get from point A to point B. We first focus on how a configured deployment looks like and only later we will discuss how and when the configuration is created. Personally I found it very valuable to see the actual interfaces and how they connect to each other through examples and hands on experiments. After the end game is clear and we know how the connectivity works, in a later post, we will take a step back and explain how Neutron configures the components to be able to provide such connectivity.  We are going to get pretty technical shortly and I recommend trying these examples on your own deployment or using the Oracle OpenStack Tech Preview. Understanding these three use cases thoroughly and how to look at them will be very helpful when trying to debug a deployment in case something does not work. Use case #1: Create Network Create network is a simple operation it can be performed from the GUI or command line. When we create a network in OpenStack the network is only available to the tenant who created it or it could be defined as “shared” and then it can be used by all tenants. A network can have multiple subnets but for this demonstration purpose and for simplicity we will assume that each network has exactly one subnet. Creating a network from the command line will look like this: # neutron net-create net1 Created a new network: +---------------------------+--------------------------------------+ | Field                     | Value                                | +---------------------------+--------------------------------------+ | admin_state_up            | True                                 | | id                        | 5f833617-6179-4797-b7c0-7d420d84040c | | name                      | net1                                 | | provider:network_type     | vlan                                 | | provider:physical_network | default                              | | provider:segmentation_id  | 1000                                 | | shared                    | False                                | | status                    | ACTIVE                               | | subnets                   |                                      | | tenant_id                 | 9796e5145ee546508939cd49ad59d51f     | +---------------------------+--------------------------------------+ Creating a subnet for this network will look like this: # neutron subnet-create net1 10.10.10.0/24 Created a new subnet: +------------------+------------------------------------------------+ | Field            | Value                                          | +------------------+------------------------------------------------+ | allocation_pools | {"start": "10.10.10.2", "end": "10.10.10.254"} | | cidr             | 10.10.10.0/24                                  | | dns_nameservers  |                                                | | enable_dhcp      | True                                           | | gateway_ip       | 10.10.10.1                                     | | host_routes      |                                                | | id               | 2d7a0a58-0674-439a-ad23-d6471aaae9bc           | | ip_version       | 4                                              | | name             |                                                | | network_id       | 5f833617-6179-4797-b7c0-7d420d84040c           | | tenant_id        | 9796e5145ee546508939cd49ad59d51f               | +------------------+------------------------------------------------+ We now have a network and a subnet, on the network topology view this looks like this: Now let’s dive in and see what happened under the hood. Looking at the control node we will discover that a new namespace was created: # ip netns list qdhcp-5f833617-6179-4797-b7c0-7d420d84040c   The name of the namespace is qdhcp-<network id> (see above), let’s look into the namespace and see what’s in it: # ip netns exec qdhcp-5f833617-6179-4797-b7c0-7d420d84040c ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00     inet 127.0.0.1/8 scope host lo     inet6 ::1/128 scope host        valid_lft forever preferred_lft forever 12: tap26c9b807-7c: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN     link/ether fa:16:3e:1d:5c:81 brd ff:ff:ff:ff:ff:ff     inet 10.10.10.3/24 brd 10.10.10.255 scope global tap26c9b807-7c     inet6 fe80::f816:3eff:fe1d:5c81/64 scope link        valid_lft forever preferred_lft forever   We see two interfaces in the namespace, one is the loopback and the other one is an interface called “tap26c9b807-7c”. This interface has the IP address of 10.10.10.3 and it will also serve dhcp requests in a way we will see later. Let’s trace the connectivity of the “tap26c9b807-7c” interface from the namespace.  First stop is OVS, we see that the interface connects to bridge  “br-int” on OVS: # ovs-vsctl show 8a069c7c-ea05-4375-93e2-b9fc9e4b3ca1     Bridge "br-eth2"         Port "br-eth2"             Interface "br-eth2"                 type: internal         Port "eth2"             Interface "eth2"         Port "phy-br-eth2"             Interface "phy-br-eth2"     Bridge br-ex         Port br-ex             Interface br-ex                 type: internal     Bridge br-int         Port "int-br-eth2"             Interface "int-br-eth2"         Port "tap26c9b807-7c"             tag: 1             Interface "tap26c9b807-7c"                 type: internal         Port br-int             Interface br-int                 type: internal     ovs_version: "1.11.0"   In the picture above we have a veth pair which has two ends called “int-br-eth2” and "phy-br-eth2", this veth pair is used to connect two bridge in OVS "br-eth2" and "br-int". In the previous post we explained how to check the veth connectivity using the ethtool command. It shows that the two are indeed a pair: # ethtool -S int-br-eth2 NIC statistics:      peer_ifindex: 10 . .   #ip link . . 10: phy-br-eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 . . Note that “phy-br-eth2” is connected to a bridge called "br-eth2" and one of this bridge's interfaces is the physical link eth2. This means that the network which we have just created has created a namespace which is connected to the physical interface eth2. eth2 is the “VM network” the physical interface where all the virtual machines connect to where all the VMs are connected. About network isolation: OpenStack supports creation of multiple isolated networks and can use several mechanisms to isolate the networks from one another. The isolation mechanism can be VLANs, VxLANs or GRE tunnels, this is configured as part of the initial setup in our deployment we use VLANs. When using VLAN tagging as an isolation mechanism a VLAN tag is allocated by Neutron from a pre-defined VLAN tags pool and assigned to the newly created network. By provisioning VLAN tags to the networks Neutron allows creation of multiple isolated networks on the same physical link.  The big difference between this and other platforms is that the user does not have to deal with allocating and managing VLANs to networks. The VLAN allocation and provisioning is handled by Neutron which keeps track of the VLAN tags, and responsible for allocating and reclaiming VLAN tags. In the example above net1 has the VLAN tag 1000, this means that whenever a VM is created and connected to this network the packets from that VM will have to be tagged with VLAN tag 1000 to go on this particular network. This is true for namespace as well, if we would like to connect a namespace to a particular network we have to make sure that the packets to and from the namespace are correctly tagged when they reach the VM network. In the example above we see that the namespace interface “tap26c9b807-7c” has vlan tag 1 assigned to it, if we examine OVS we see that it has flows which modify VLAN tag 1 to VLAN tag 1000 when a packet goes to the VM network on eth2 and vice versa. We can see this using the dump-flows command on OVS for packets going to the VM network we see the modification done on br-eth2: #  ovs-ofctl dump-flows br-eth2 NXST_FLOW reply (xid=0x4):  cookie=0x0, duration=18669.401s, table=0, n_packets=857, n_bytes=163350, idle_age=25, priority=4,in_port=2,dl_vlan=1 actions=mod_vlan_vid:1000,NORMAL  cookie=0x0, duration=165108.226s, table=0, n_packets=14, n_bytes=1000, idle_age=5343, hard_age=65534, priority=2,in_port=2 actions=drop  cookie=0x0, duration=165109.813s, table=0, n_packets=1671, n_bytes=213304, idle_age=25, hard_age=65534, priority=1 actions=NORMAL   For packets coming from the interface to the namespace we see the following modification: #  ovs-ofctl dump-flows br-int NXST_FLOW reply (xid=0x4):  cookie=0x0, duration=18690.876s, table=0, n_packets=1610, n_bytes=210752, idle_age=1, priority=3,in_port=1,dl_vlan=1000 actions=mod_vlan_vid:1,NORMAL  cookie=0x0, duration=165130.01s, table=0, n_packets=75, n_bytes=3686, idle_age=4212, hard_age=65534, priority=2,in_port=1 actions=drop  cookie=0x0, duration=165131.96s, table=0, n_packets=863, n_bytes=160727, idle_age=1, hard_age=65534, priority=1 actions=NORMAL   To summarize we can see that when a user creates a network Neutron creates a namespace and this namespace is connected through OVS to the “VM network”. OVS also takes care of tagging the packets from the namespace to the VM network with the correct VLAN tag and knows to modify the VLAN for packets coming from VM network to the namespace. Now let’s see what happens when a VM is launched and how it is connected to the “VM network”. Use case #2: Launch a VM Launching a VM can be done from Horizon or from the command line this is how we do it from Horizon: Attach the network: And Launch Once the virtual machine is up and running we can see the associated IP using the nova list command : # nova list +--------------------------------------+--------------+--------+------------+-------------+-----------------+ | ID                                   | Name         | Status | Task State | Power State | Networks        | +--------------------------------------+--------------+--------+------------+-------------+-----------------+ | 3707ac87-4f5d-4349-b7ed-3a673f55e5e1 | Oracle Linux | ACTIVE | None       | Running     | net1=10.10.10.2 | +--------------------------------------+--------------+--------+------------+-------------+-----------------+ The nova list command shows us that the VM is running and that the IP 10.10.10.2 is assigned to this VM. Let’s trace the connectivity from the VM to VM network on eth2 starting with the VM definition file. The configuration files of the VM including the virtual disk(s), in case of ephemeral storage, are stored on the compute node at/var/lib/nova/instances/<instance-id>/. Looking into the VM definition file ,libvirt.xml,  we see that the VM is connected to an interface called “tap53903a95-82” which is connected to a Linux bridge called “qbr53903a95-82”: <interface type="bridge">       <mac address="fa:16:3e:fe:c7:87"/>       <source bridge="qbr53903a95-82"/>       <target dev="tap53903a95-82"/>     </interface>   Looking at the bridge using the brctl show command we see this: # brctl show bridge name     bridge id               STP enabled     interfaces qbr53903a95-82          8000.7e7f3282b836       no              qvb53903a95-82                                                         tap53903a95-82    The bridge has two interfaces, one connected to the VM (“tap53903a95-82 “) and another one ( “qvb53903a95-82”) connected to “br-int” bridge on OVS: # ovs-vsctl show 83c42f80-77e9-46c8-8560-7697d76de51c     Bridge "br-eth2"         Port "br-eth2"             Interface "br-eth2"                 type: internal         Port "eth2"             Interface "eth2"         Port "phy-br-eth2"             Interface "phy-br-eth2"     Bridge br-int         Port br-int             Interface br-int                 type: internal         Port "int-br-eth2"             Interface "int-br-eth2"         Port "qvo53903a95-82"             tag: 3             Interface "qvo53903a95-82"     ovs_version: "1.11.0"   As we showed earlier “br-int” is connected to “br-eth2” on OVS using the veth pair int-br-eth2,phy-br-eth2 and br-eth2 is connected to the physical interface eth2. The whole flow end to end looks like this: VM è tap53903a95-82 (virtual interface)è qbr53903a95-82 (Linux bridge) è qvb53903a95-82 (interface connected from Linux bridge to OVS bridge br-int) è int-br-eth2 (veth one end) è phy-br-eth2 (veth the other end) è eth2 physical interface. The purpose of the Linux Bridge connecting to the VM is to allow security group enforcement with iptables. Security groups are enforced at the edge point which are the interface of the VM, since iptables nnot be applied to OVS bridges we use Linux bridge to apply them. In the future we hope to see this Linux Bridge going away rules.  VLAN tags: As we discussed in the first use case net1 is using VLAN tag 1000, looking at OVS above we see that qvo41f1ebcf-7c is tagged with VLAN tag 3. The modification from VLAN tag 3 to 1000 as we go to the physical network is done by OVS  as part of the packet flow of br-eth2 in the same way we showed before. To summarize, when a VM is launched it is connected to the VM network through a chain of elements as described here. During the packet from VM to the network and back the VLAN tag is modified. Use case #3: Serving a DHCP request coming from the virtual machine In the previous use cases we have shown that both the namespace called dhcp-<some id> and the VM end up connecting to the physical interface eth2  on their respective nodes, both will tag their packets with VLAN tag 1000.We saw that the namespace has an interface with IP of 10.10.10.3. Since the VM and the namespace are connected to each other and have interfaces on the same subnet they can ping each other, in this picture we see a ping from the VM which was assigned 10.10.10.2 to the namespace: The fact that they are connected and can ping each other can become very handy when something doesn’t work right and we need to isolate the problem. In such case knowing that we should be able to ping from the VM to the namespace and back can be used to trace the disconnect using tcpdump or other monitoring tools. To serve DHCP requests coming from VMs on the network Neutron uses a Linux tool called “dnsmasq”,this is a lightweight DNS and DHCP service you can read more about it here. If we look at the dnsmasq on the control node with the ps command we see this: dnsmasq --no-hosts --no-resolv --strict-order --bind-interfaces --interface=tap26c9b807-7c --except-interface=lo --pid-file=/var/lib/neutron/dhcp/5f833617-6179-4797-b7c0-7d420d84040c/pid --dhcp-hostsfile=/var/lib/neutron/dhcp/5f833617-6179-4797-b7c0-7d420d84040c/host --dhcp-optsfile=/var/lib/neutron/dhcp/5f833617-6179-4797-b7c0-7d420d84040c/opts --leasefile-ro --dhcp-range=tag0,10.10.10.0,static,120s --dhcp-lease-max=256 --conf-file= --domain=openstacklocal The service connects to the tap interface in the namespace (“--interface=tap26c9b807-7c”), If we look at the hosts file we see this: # cat  /var/lib/neutron/dhcp/5f833617-6179-4797-b7c0-7d420d84040c/host fa:16:3e:fe:c7:87,host-10-10-10-2.openstacklocal,10.10.10.2   If you look at the console output above you can see the MAC address fa:16:3e:fe:c7:87 which is the VM MAC. This MAC address is mapped to IP 10.10.10.2 and so when a DHCP request comes with this MAC dnsmasq will return the 10.10.10.2.If we look into the namespace at the time we initiate a DHCP request from the VM (this can be done by simply restarting the network service in the VM) we see the following: # ip netns exec qdhcp-5f833617-6179-4797-b7c0-7d420d84040c tcpdump -n 19:27:12.191280 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:fe:c7:87, length 310 19:27:12.191666 IP 10.10.10.3.bootps > 10.10.10.2.bootpc: BOOTP/DHCP, Reply, length 325   To summarize, the DHCP service is handled by dnsmasq which is configured by Neutron to listen to the interface in the DHCP namespace. Neutron also configures dnsmasq with the combination of MAC and IP so when a DHCP request comes along it will receive the assigned IP. Summary In this post we relied on the components described in the previous post and saw how network connectivity is achieved using three simple use cases. These use cases gave a good view of the entire network stack and helped understand how an end to end connection is being made between a VM on a compute node and the DHCP namespace on the control node. One conclusion we can draw from what we saw here is that if we launch a VM and it is able to perform a DHCP request and receive a correct IP then there is reason to believe that the network is working as expected. We saw that a packet has to travel through a long list of components before reaching its destination and if it has done so successfully this means that many components are functioning properly. In the next post we will look at some more sophisticated services Neutron supports and see how they work. We will see that while there are some more components involved for the most part the concepts are the same. @RonenKofman

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• Exalogic 2.0.1 Tea Break Snippets - Creating a ModifyJeOS VirtualBox

  - by The Old Toxophilist

  Following on from my previous blog entry "Modifying the Base Template" I decided to put together a quick blog to show how to create a small VirtualBox, guest, that can be used to execute the ModifyJeOS and hence edit you templates. One of the main advantages of this is that Templates can be created away from the Exalogic Environment. For the Guest OS I chose OEL 6u3 and decided to create it as a basic server because I did not require a graphical interface but it's a simple change to create it with a GUI. Required Software Virtual Box. Oracle Enterprise Linux. Creating the VM I'll assume that the reader is experienced with Virtual Box and installing OEL and hence will make this section brief. Create VirtualBox Guest Create a new VirtualBox Guest and select oracle Linux 64 bit. Follow through the create process and select Dynamic Disk Size and the default 12GB disk size. The actual image will be a lot smaller than this but the OEL install will fail with insufficient disk space if you attempt a smaller size. Once the guest has been created attach the previously downloaded OEL 6u3 iso to the cd drive and start the guest. Install OEL On starting the guest the system will boot off the associated OEL 6u3 iso and take you through the standard installation process. Select all the appropriate information but when you reach the installation type select Basic Server because we do not need that additional packages and only need to access through the command line interface. Complete the installation and reboot the Guest. At this point we now have a basic OEL server running. Installing Guest Add-ons Before we can easily access the Guest we will need to add the VirtualBox guest add-ons. These will provide better keyboard and mouse integration and allow access the shared folders on the host machine. Before we can do this we will need to do the following: Enable Networking. Install additional rpms.  To enable the networking (eth0), that appears to be disabled by default, we can execute: ifup eth0 This will start the eth0 connection but once the Guest is rebooted the network will be down again. To resolve this you will need to edit the /etc/sysconfig/network-scripts/ifcfg-eth0 file and change the ONBOOT parameter to "yes". Now we have enabled the network we will need to install a number of addition rpm. First we will need to configure the yum repository as follows: [ol6_latest] name=Oracle Linux $releasever Latest ($basearch) baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/latest/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=1 [ol6_ga_base] name=Oracle Linux $releasever GA installation media copy ($basearch) baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/0/base/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=0 [ol6_u1_base] name=Oracle Linux $releasever Update 1 installation media copy ($basearch) baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/1/base/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=0 [ol6_u2_base] name=Oracle Linux $releasever Update 2 installation media copy ($basearch) baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/2/base/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=0 [ol6_u3_base] name=Oracle Linux $releasever Update 3 installation media copy ($basearch) baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/3/base/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=0 [ol6_UEK_latest] name=Latest Unbreakable Enterprise Kernel for Oracle Linux $releasever ($basearch) baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/UEK/latest/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=1 [ol6_UEK_base] name=Unbreakable Enterprise Kernel for Oracle Linux $releasever ($basearch) baseurl=http://public-yum.oracle.com/repo/OracleLinux/OL6/UEK/base/$basearch/ gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-ol6 gpgcheck=1 enabled=0 Once the repository has been edited we will need to execute the following yum commands: yum update yum install gcc yum install kernel-uek-devel yum install kernel-devel yum install createrepo At this point we now have all the additional packages required to install the VirtualBox Guest Add-ons. So select Devices->InstallGuest Additions on you running guest: This will simply place the VirtualBoxGuestAdditions.iso in the virtual cd and we will need to execute the following before we can run them. mkdir /media/cdrom mount -t iso9660 -o ro /dev/cdrom /media/cdrom cd /media/cdrom/ ls ./VBoxLinuxAdditions.run This will initiate the install and kernel rebuild. What you will notice is that during the installation a Failed will be displayed but this is simply because we have no graphical components. At this point we the installation will also have added the vboxsf group to the system and to access any shared folders we will create our user will need to be a member of this group an so the next stage is to add the root user to this group as follows: usermod -G vboxsf root cat /etc/group cat /etc/passwd init 0 Now simply shutdown the guest and add the Shared folder within your guests settings. Install ModifyJeOS Once the shared folder has been added restart the guest and change directory into the shared folder (/media/sf_<folder name>). For the next step I am assuming the ModifyJeOS rpms are located in the shared folder. We can simply execute: rpm -ivh ovm-modify-jeos-1.1.0-17.el5.noarch.rpm # Test with modifyjeos Using ModifyJeOS I have a modified MountSystemImg.sh script that should be copied into the /root/bin directory (you may need to create this) and from here it can be executed from any location: MountSystemImg.sh #!/bin/sh # The script assumes it's being run from the directory containing the System.img # Export for later i.e. during unmount export LOOP=`losetup -f` export SYSTEMIMG=/mnt/elsystem export TEMPLATEDIR=`pwd` # Make Temp Mount Directory mkdir -p $SYSTEMIMG # Create Loop for the System Image losetup $LOOP System.img kpartx -a $LOOP mount /dev/mapper/`basename $LOOP`p2 $SYSTEMIMG #Change Dir into mounted Image cd $SYSTEMIMG echo "######################################################################" echo "### ###" echo "### Starting Bash shell for editing. When completed log out to ###" echo "### Unmount the System.img file. ###" echo "### ###" echo "######################################################################" echo bash cd ~ cd $TEMPLATEDIR umount $SYSTEMIMG kpartx -d $LOOP losetup -d $LOOP rm -rf $SYSTEMIMG This script will simple create a mount directory, mount the System.img and then start a new shell in the mounted directory. On exiting the shell it will unmount the System.img. It only requires that you execute the script in the directory containing the System.img. These can be created under the mounted shared directory. In the example below I have extracted the Base template within the shared folder and then renamed it OEL_40GB_ROOT before changing into that directory and executing the script.

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• ApiChange Is Released!

  - by Alois Kraus

  I have been working on little tool to simplify my life and perhaps yours as developer as well. It is basically a command line tool that allows you to execute queries on your compiled .NET code base. The main purpose is to find out how big the impact of an api change would be if you changed this or that.  Now you can do high level operations like Diff public types for breaking changes. Who uses a method? Who uses a type? Who uses implements an interface? Who references me? What format has the binary  (32/64, Managed C++, Pure IL, Unmanaged)? Search for all event subscribers and unsubscribers. A unique feature is to check for event subscription imbalances. Forgotten event subscriptions are the 90% cause of managed memory leaks. It is done at a per class level. If one class does subscribe to one event more often than it does unsubscribe it is treated as possible event subscription imbalance. Another unique ability is to search for users of string literals which allows you to track users of a string constant which is not possible otherwise. For incremental builds the ShowRebuildTargets command can be used to identify the dependant targets that need a rebuild after you did compile one assembly. It has some heuristics in place to determine the impact of breaking changes and finds out which targets need to be recompiled as well. It has a ton of other features and a an API to access these things programmatically so you can build upon these simple queries create even better tools. Perhaps we get a Visual Studio plug in? You can download it from CodePlex here. It works via XCopy deployment. Simply let it run and check the command line help out. The best feature in my opinion is that the output of nearly all commands can be piped to Excel for further analysis. Since it does read also the pdbs it can show you the source file name and line number as well for all matches. The following picture shows the output of a –WhousesType query. The following command checks where type from BaseLibraryV1.dll are used inside DependantLibV1.dll. All matches are printed out with the reason and matching item along with file and line number. There is even a hyper link to the match which will open Visual Studio. ApiChange -whousestype "*" BaseLibraryV1.dll -in DependantLibV1.dll –excel The "*” is the actual query which means all types. The syntax is the same like in C# just that placeholders are allowed ;-). More info's can be found at the Codeplex Documentation.     The tool was developed in a TDD style manner which means that it is heavily tested and already used by a quite large user base inside the company I do work for. Luckily for you I got the permission to make it public so you take advantage of it. It is fully instrumented with tracing. If you find bugs simply add the –trace command line switch to find out what is failing and send me the output. How is it done? Your first guess might be that it uses reflection. Wrong. It is based on Mono Cecil a free IL parser with a fantastic API to access all internals of a managed assembly. The speed is awesome and to make it even faster I did make the tool heavily multi threaded. The query above did execute in 1.8s with the Excel output. On a rather slow machine I can analyze over 1500 assemblies in less than 40s with a very low memory consumption. The true power of Mono Cecil is that I can load an assembly like any other data file. I have no problems unloading a file but if I would have used reflection I would need to unload a whole AppDomain just to get rid of one assembly in my memory. Just to give you a glimpse how ApiChange.Api.dll can be used I show you one of the unit tests:           public void Can_Find_GenericMethodInvocations_With_Type_Parameters()         { // 1. Create an aggregator to collect our matches             UsageQueryAggregator agg = new UsageQueryAggregator();   // 2. This is the type we want to search for. Load it via the type query             var decimalType = TypeQuery.GetTypeByName(TestConstants.MscorlibAssembly, "System.Decimal");   // 3. register the type query which searches for uses of the Decimal type             new WhoUsesType(agg, decimalType);   // 4. Search for all users of the Decimal type in the DependandLibV1Assembly             agg.Analyze(TestConstants.DependandLibV1Assembly);   // Extract matches and assert             Assert.AreEqual(2, agg.MethodMatches.Count, "Method match count");             Assert.AreEqual("UseGenericMethod", agg.MethodMatches[0].Match.Name);             Assert.AreEqual("UseGenericMethod", agg.MethodMatches[1].Match.Name);         } Many thanks go from here to Jb Evian for the creation of Mono.Cecil. Without this fantastic piece of code it would have been much much harder. There are other options around like the Common Compiler Infrastructure  Metadata Api which should do the same thing but it was not a real option since the Microsoft reader did fail on even simple assemblies (at least in September 2009 this was the case). Besides this I found the CCI Apis much harder to use. The only real competitor was Reflector which does support many things but does not let me access his cool high level analyze commands. So I decided to dig into the IL specs and as a result you can query your compiled binaries from the command line or programmatically. The best thing is you try it out for yourself and give me some feedback what you miss. If you want to contribute or have a cool idea what should be added drop me a mail at A Kraus1@___No [email protected]. There is much more inside the tool I did not talk about it (yet).

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• BizTalk: Internals: the Partner Direct Ports and the Orchestration Chains

  - by Leonid Ganeline

  Partner Direct Port is one of the BizTalk hidden gems. It opens simple ways to the several messaging patterns. This article based on the Kevin Lam’s blog article. The article is pretty detailed but it still leaves several unclear pieces. So I have created a sample and will show how it works from different perspectives. Requirements We should create an orchestration chain where the messages should be routed from the first stage to the second stage. The messages should not be modified. All messages has the same message type. Common artifacts Source code can be downloaded here. It is interesting but all orchestrations use only one port type. It is possible because all ports are one-way ports and use only one operation. I have added a B orchestration. It helps to test the sample, showing all test messages in channel. The Receive shape Filter is empty. A Receive Port (R_Shema1Direct) is a plain Direct Port. As you can see, a subscription expression of this direct port has only one part, the MessageType for our test schema: A Filer is empty but, as you know, a link from the Receive shape to the Port creates this MessageType expression. I use only one Physical Receive File port to send a message to all processes. Each orchestration outputs a Trace.WriteLine(“<Orchestration Name>”). Forward Binding This sample has three orchestrations: A_1, A_21 and A_22. A_1 is a sender, A_21 and A_22 are receivers. Here is a subscription of the A_1 orchestration: It has two parts A MessageType. The same was for the B orchestration. A ReceivePortID. There was no such parameter for the B orchestration. It was created because I have bound the orchestration port with Physical Receive File port. This binding means the PortID parameter is added to the subscription. How to set up the ports? All ports involved in the message exchange should be the same port type. It forces us to use the same operation and the same message type for the bound ports. This step as absolutely contra-intuitive. We have to choose a Partner Orchestration parameter for the sending orchestration, A_1. The first strange thing is it is not a partner orchestration we have to choose but an orchestration port. But the most strange thing is we have to choose exactly this orchestration and exactly this port.It is not a port from the partner, receive orchestrations, A_21 or A_22, but it is A_1 orchestration and S_SentFromA_1 port. Now we have to choose a Partner Orchestration parameter for the received orchestrations, A_21 and A_22. Nothing strange is here except a parameter name. We choose the port of the sender, A_1 orchestration and S_SentFromA_1 port. As you can see the Partner Orchestration parameter for the sender and receiver orchestrations is the same. Testing I dropped a test file in a file folder. There we go: A dropped file was received by B and by A_1 A_1 sent a message forward. A message was received by B, A_21, A_22 Let’s look at a context of a message sent by A_1 on the second step: A MessageType part. It is quite expected. A PartnerService, a ParnerPort, an Operation. All those parameters were set up in the Partner Orchestration parameter on both bound ports.     Now let’s see a subscription of the A_21 and A_22 orchestrations. Now it makes sense. That’s why we have chosen such a strange value for the Partner Orchestration parameter of the sending orchestration. Inverse Binding This sample has three orchestrations: A_11, A_12 and A_2. A_11 and A_12 are senders, A_2 is receiver. How to set up the ports? All ports involved in the message exchange should be the same port type. It forces us to use the same operation and the same message type for the bound ports. This step as absolutely contra-intuitive. We have to choose a Partner Orchestration parameter for a receiving orchestration, A_2. The first strange thing is it is not a partner orchestration we have to choose but an orchestration port. But the most strange thing is we have to choose exactly this orchestration and exactly this port.It is not a port from the partner, sent orchestrations, A_11 or A_12, but it is A_2 orchestration and R_SentToA_2 port. Now we have to choose a Partner Orchestration parameter for the sending orchestrations, A_11 and A_12. Nothing strange is here except a parameter name. We choose the port of the sender, A_2 orchestration and R_SentToA_2 port. Testing I dropped a test file in a file folder. There we go: A dropped file was received by B, A_11 and by A_12 A_11 and A_12 sent two messages forward. The messages were received by B, A_2 Let’s see what was a context of a message sent by A_1 on the second step: A MessageType part. It is quite expected. A PartnerService, a ParnerPort, an Operation. All those parameters were set up in the Partner Orchestration parameter on both bound ports. Here is a subscription of the A_2 orchestration. Models I had a hard time trying to explain the Partner Direct Ports in simple terms. I have finished with this model: Forward Binding Receivers know a Sender. Sender doesn’t know Receivers. Publishers know a Subscriber. Subscriber doesn’t know Publishers. 1 –> 1 1 –> M Inverse Binding Senders know a Receiver. Receiver doesn’t know Senders. Subscribers know a Publisher. Publisher doesn’t know Subscribers. 1 –> 1 M –> 1 Notes   Orchestration chain It’s worth to note, the Partner Direct Port Binding creates a chain opened from one side and closed from another. The Forward Binding: A new Receiver can be added at run-time. The Sender can not be changed without design-time changes in Receivers. The Inverse Binding: A new Sender can be added at run-time. The Receiver can not be changed without design-time changes in Senders.

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• CodePlex Daily Summary for Monday, August 11, 2014

  CodePlex Daily Summary for Monday, August 11, 2014Popular ReleasesSpace Engineers Server Manager: SESM V1.15: V1.15 - Updated Quartz library - Correct a bug in the new mod managment - Added a warning if you have backup enabled on a server but no static map configuredAspose for Apache POI: Missing Features of Apache POI SS - v 1.2: Release contain the Missing Features in Apache POI SS SDK in comparison with Aspose.Cells What's New ? Following Examples: Create Pivot Charts Detect Merged Cells Sort Data Printing Workbooks Feedback and Suggestions Many more examples are available at Aspose Docs. Raise your queries and suggest more examples via Aspose Forums or via this social coding site.AngularGo (SPA Project Template): AngularGo.VS2013.vsix: First ReleaseTouchmote: Touchmote 1.0 beta 13: Changes Less GPU usage Works together with other Xbox 360 controls Bug fixesPublic Key Infrastructure PowerShell module: PowerShell PKI Module v3.0: Important: I would like to hear more about what you are thinking about the project? I appreciate that you like it (2000 downloads over past 6 months), but may be you have to say something? What do you dislike in the module? Maybe you would love to see some new functionality? Tell, what you think! Installation guide:Use default installation path to install this module for current user only. To install this module for all users — enable "Install for all users" check-box in installation UI ...Modern UI for WPF: Modern UI 1.0.6: The ModernUI assembly including a demo app demonstrating the various features of Modern UI for WPF. BREAKING CHANGE LinkGroup.GroupName renamed to GroupKey NEW FEATURES Improved rendering on high DPI screens, including support for per-monitor DPI awareness available in Windows 8.1 (see also Per-monitor DPI awareness) New ModernProgressRing control with 8 builtin styles New LinkCommands.NavigateLink routed command New Visual Studio project templates 'Modern UI WPF App' and 'Modern UI W...ClosedXML - The easy way to OpenXML: ClosedXML 0.74.0: Multiple thread safe improvements including AdjustToContents XLHelper XLColor_Static IntergerExtensions.ToStringLookup Exception now thrown when saving a workbook with no sheets, instead of creating a corrupt workbook Fix for hyperlinks with non-ASCII Characters Added basic workbook protection Fix for error thrown, when a spreadsheet contained comments and images Fix to Trim function Fix Invalid operation Exception thrown when the formula functions MAX, MIN, and AVG referenc...SEToolbox: SEToolbox 01.042.019 Release 1: Added RadioAntenna broadcast name to ship name detail. Added two additional columns for Asteroid material generation for Asteroid Fields. Added Mass and Block number columns to main display. Added Ellipsis to some columns on main display to reduce name confusion. Added correct SE version number in file when saving. Re-added in reattaching Motor when drag/dropping or importing ships (KeenSH have added RotorEntityId back in after removing it months ago). Added option to export and r...jQuery List DragSort: jQuery List DragSort 0.5.2: Fixed scrollContainer removing deprecated use of $.browser so should now work with latest version of jQuery. Added the ability to return false in dragEnd to revert sort order Project changes Added nuget package for dragsort https://www.nuget.org/packages/dragsort Converted repository from SVN to MercurialBraintree Client Library: Braintree 2.32.0: Allow credit card verification options to be passed outside of the nonce for PaymentMethod.create Allow billingaddress parameters and billingaddress_id to be passed outside of the nonce for PaymentMethod.create Add Subscriptions to paypal accounts Add PaymentMethod.update Add failonduplicatepaymentmethod option to PaymentMethod.create Add support for dispute webhooksThe Mario Kart 8 App: V1.0.2.1: First Codeplex release. WINDOWS INSTALLER ONLYAspose Java for Docx4j: Aspose.Words vs Docx4j - v 1.0: Release contain the Code Comparison for Features in Docx4j SDK and Aspose.Words What's New ?Following Examples: Accessing Document Properties Add Bookmarks Convert to Formats Delete Bookmarks Working with Comments Feedback and Suggestions Many more examples are available at Aspose Docs. Raise your queries and suggest more examples via Aspose Forums or via this social coding site.File System Security PowerShell Module: NTFSSecurity 2.4.1: Add-Access and Remove-Access now take multiple accoutsYourSqlDba: YourSqlDba 5.2.1.: This version improves alert message that comes a while after you install the script. First it says to get it from YourSqlDba.CodePlex.com If you don't want to update now, just-rerun the script from your installed version. To get actual version running just execute install.PrintVersionInfo. . You can go to source code / history and click on change set 72957 to see changes in the script.Manipulator: Manipulator: manipulatorXNB filetype plugin for Paint.NET: Paint.NET XNB plugin v0.4.0.0: CHANGELOG Reverted old incomplete changes. Updated library for compatibility with Paint .NET 4. Updated project to NET 4.5. Updated version to 0.4.0.0. INSTALLATION INSTRUCTIONS Extract the ZIP file to your Paint.NET\FileTypes folder.EdiFabric: Release 4.1: Changed MessageContextWix# (WixSharp) - managed interface for WiX: Release 1.0.0.0: Release 1.0.0.0 Custom UI Custom MSI Dialog Custom CLR Dialog External UIMath.NET Numerics: Math.NET Numerics v3.2.0: Linear Algebra: Vector.Map2 (map2 in F#), storage-optimized Linear Algebra: fix RemoveColumn/Row early index bound check (was not strict enough) Statistics: Entropy ~Jeff Mastry Interpolation: use Array.BinarySearch instead of local implementation ~Candy Chiu Resources: fix a corrupted exception message string Portable Build: support .Net 4.0 as well by using profile 328 instead of 344. .Net 3.5: F# extensions now support .Net 3.5 as well .Net 3.5: NuGet package now contains pro...babelua: 1.6.5.1: V1.6.5.1 - 2014.8.7New feature: Formatting code; Stability improvement: fix a bug that pop up error "System.Net.WebResponse EndGetResponse";New ProjectsDouDou: a little project.Dynamic MVC: Dynamically generate views from your model objects for a data centric MVC application.EasyDb - Simple Data Access: EasyDb is a simple library for data access that allows you to write less code.ExpressToAbroad: just go!!!!!Full Silverlight Web Video/Voice Conferencing: The Goal of this project is to provide complete Open Source (Voice/Video Chatting Client/Server) Modules Using SilverlightGaia: Gaia is an app for Windows plataform, Gaia is like Siri and Google Now or Betty but Gaia use only text commands.pxctest: pxctestSTACS: Career Management System for MIT by Team "STACS"StrongWorld: StrongWorld.WebSuiteXevas Tools: Xevas is a professional coders group of 'Nimbuzz'. We make all tools for worldwide users of nimbuzz at free of cost.????????: ????????????????: ???????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ????????????????: ????????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ????????????????: ????????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ???????????????: ????????????????: ???????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ??????????????: ????????????????: ????????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ??????????????: ???????????????: ???????????????: ??????????????: ??????????????: ??????????????: ????????????????: ?????????

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• General Purpose ASP.NET Data Source Control

  - by Ricardo Peres

  OK, you already know about the ObjectDataSource control, so what’s wrong with it? Well, for once, it doesn’t pass any context to the SelectMethod, you only get the parameters supplied on the SelectParameters plus the desired ordering, starting page and maximum number of rows to display. Also, you must have two separate methods, one for actually retrieving the data, and the other for getting the total number of records (SelectCountMethod). Finally, you don’t get a chance to alter the supplied data before you bind it to the target control. I wanted something simple to use, and more similar to ASP.NET 4.5, where you can have the select method on the page itself, so I came up with CustomDataSource. Here’s how to use it (I chose a GridView, but it works equally well with any regular data-bound control): 1: <web:CustomDataSourceControl runat="server" ID="datasource" PageSize="10" OnData="OnData" /> 2: <asp:GridView runat="server" ID="grid" DataSourceID="datasource" DataKeyNames="Id" PageSize="10" AllowPaging="true" AllowSorting="true" /> The OnData event handler receives a DataEventArgs instance, which contains some properties that describe the desired paging location and size, and it’s where you return the data plus the total record count. Here’s a quick example: 1: protected void OnData(object sender, DataEventArgs e) 2: { 3: //just return some data 4: var data = Enumerable.Range(e.StartRowIndex, e.PageSize).Select(x => new { Id = x, Value = x.ToString(), IsPair = ((x % 2) == 0) }); 5: e.Data = data; 6: //the total number of records 7: e.TotalRowCount = 100; 8: } Here’s the code for the DataEventArgs: 1: [Serializable] 2: public class DataEventArgs : EventArgs 3: { 4: public DataEventArgs(Int32 pageSize, Int32 startRowIndex, String sortExpression, IOrderedDictionary parameters) 5: { 6: this.PageSize = pageSize; 7: this.StartRowIndex = startRowIndex; 8: this.SortExpression = sortExpression; 9: this.Parameters = parameters; 10: } 11:  12: public IEnumerable Data 13: { 14: get; 15: set; 16: } 17:  18: public IOrderedDictionary Parameters 19: { 20: get; 21: private set; 22: } 23:  24: public String SortExpression 25: { 26: get; 27: private set; 28: } 29:  30: public Int32 StartRowIndex 31: { 32: get; 33: private set; 34: } 35:  36: public Int32 PageSize 37: { 38: get; 39: private set; 40: } 41:  42: public Int32 TotalRowCount 43: { 44: get; 45: set; 46: } 47: } As you can guess, the StartRowIndex and PageSize receive the starting row and the desired page size, where the page size comes from the PageSize property on the markup. There’s also a SortExpression, which gets passed the sorted-by column and direction (if descending) and a dictionary containing all the values coming from the SelectParameters collection, if any. All of these are read only, and it is your responsibility to fill in the Data and TotalRowCount. The code for the CustomDataSource is very simple: 1: [NonVisualControl] 2: public class CustomDataSourceControl : DataSourceControl 3: { 4: public CustomDataSourceControl() 5: { 6: this.SelectParameters = new ParameterCollection(); 7: } 8:  9: protected override DataSourceView GetView(String viewName) 10: { 11: return (new CustomDataSourceView(this, viewName)); 12: } 13:  14: internal void GetData(DataEventArgs args) 15: { 16: this.OnData(args); 17: } 18:  19: protected virtual void OnData(DataEventArgs args) 20: { 21: EventHandler<DataEventArgs> data = this.Data; 22:  23: if (data != null) 24: { 25: data(this, args); 26: } 27: } 28:  29: [Browsable(false)] 30: [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)] 31: [PersistenceMode(PersistenceMode.InnerProperty)] 32: public ParameterCollection SelectParameters 33: { 34: get; 35: private set; 36: } 37:  38: public event EventHandler<DataEventArgs> Data; 39:  40: public Int32 PageSize 41: { 42: get; 43: set; 44: } 45: } Also, the code for the accompanying internal – as there is no need to use it from outside of its declaring assembly - data source view: 1: sealed class CustomDataSourceView : DataSourceView 2: { 3: private readonly CustomDataSourceControl dataSourceControl = null; 4:  5: public CustomDataSourceView(CustomDataSourceControl dataSourceControl, String viewName) : base(dataSourceControl, viewName) 6: { 7: this.dataSourceControl = dataSourceControl; 8: } 9:  10: public override Boolean CanPage 11: { 12: get 13: { 14: return (true); 15: } 16: } 17:  18: public override Boolean CanRetrieveTotalRowCount 19: { 20: get 21: { 22: return (true); 23: } 24: } 25:  26: public override Boolean CanSort 27: { 28: get 29: { 30: return (true); 31: } 32: } 33:  34: protected override IEnumerable ExecuteSelect(DataSourceSelectArguments arguments) 35: { 36: IOrderedDictionary parameters = this.dataSourceControl.SelectParameters.GetValues(HttpContext.Current, this.dataSourceControl); 37: DataEventArgs args = new DataEventArgs(this.dataSourceControl.PageSize, arguments.StartRowIndex, arguments.SortExpression, parameters); 38:  39: this.dataSourceControl.GetData(args); 40:  41: arguments.TotalRowCount = args.TotalRowCount; 42: arguments.MaximumRows = this.dataSourceControl.PageSize; 43: arguments.AddSupportedCapabilities(DataSourceCapabilities.Page | DataSourceCapabilities.Sort | DataSourceCapabilities.RetrieveTotalRowCount); 44: arguments.RetrieveTotalRowCount = true; 45:  46: if (!(args.Data is ICollection)) 47: { 48: return (args.Data.OfType<Object>().ToList()); 49: } 50: else 51: { 52: return (args.Data); 53: } 54: } 55: } As always, looking forward to hearing from you!

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• Disaster, or Migration?

  - by Rob Farley

  This post is in two parts – technical and personal. And I should point out that it’s prompted in part by this month’s T-SQL Tuesday, hosted by Allen Kinsel. First, the technical: I’ve had a few conversations with people recently about migration – moving a SQL Server database from one box to another (sometimes, but not primarily, involving an upgrade). One question that tends to come up is that of downtime. Obviously there will be some period of time between the old server being available and the new one. The way that most people seem to think of migration is this: Build a new server. Stop people from using the old server. Take a backup of the old server Restore it on the new server. Reconfigure the client applications (or alternatively, configure the new server to use the same address as the old) Make the new server online. There are other things involved, such as testing, of course. But this is essentially the process that people tell me they’re planning to follow. The bit that I want to look at today (as you’ve probably guessed from my title) is the “backup and restore” section. If a SQL database is using the Simple Recovery Model, then the only restore option is the last database backup. This backup could be full or differential. The transaction log never gets backed up in the Simple Recovery Model. Instead, it truncates regularly to stay small. One that’s using the Full Recovery Model (or Bulk-Logged) won’t truncate its log – the log must be backed up regularly. This provides the benefit of having a lot more option available for restores. It’s a requirement for most systems of High Availability, because if you’re making sure that a spare box is up-and-running, ready to take over, then you have to be interested in the logs that are happening on the current box, rather than truncating them all the time. A High Availability system such as Mirroring, Replication or Log Shipping will initialise the spare machine by restoring a full database backup (and maybe a differential backup if available), and then any subsequent log backups. Once the secondary copy is close, transactions can be applied to keep the two in sync. The main aspect of any High Availability system is to have a redundant system that is ready to take over. So the similarity for migration should be obvious. If you need to move a database from one box to another, then introducing a High Availability mechanism can help. By turning on the Full Recovery Model and then taking a backup (so that the now-interesting logs have some context), logs start being kept, and are therefore available for getting the new box ready (even if it’s an upgraded version). When the migration is ready to occur, a failover can be done, letting the new server take over the responsibility of the old, just as if a disaster had happened. Except that this is a planned failover, not a disaster at all. There’s a fine line between a disaster and a migration. Failovers can be useful in patching, upgrading, maintenance, and more. Hopefully, even an unexpected disaster can be seen as just another failover, and there can be an opportunity there – perhaps to get some work done on the principal server to increase robustness. And if I’ve just set up a High Availability system for even the simplest of databases, it’s not necessarily a bad thing. :) So now the personal: It’s been an interesting time recently... June has been somewhat odd. A court case with which I was involved got resolved (through mediation). I can’t go into details, but my lawyers tell me that I’m allowed to say how I feel about it. The answer is ‘lousy’. I don’t regret pursuing it as long as I did – but in the end I had to make a decision regarding the commerciality of letting it continue, and I’m going to look forward to the days when the kind of money I spent on my lawyers is small change. Mind you, if I had a similar situation with an employer, I’d do the same again, but that doesn’t really stop me feeling frustrated about it. The following day I had to fly to country Victoria to see my grandmother, who wasn’t expected to last the weekend. She’s still around a week later as I write this, but her 92-year-old body has basically given up on her. She’s been a Christian all her life, and is looking forward to eternity. We’ll all miss her though, and it’s hard to see my family grieving. Then on Tuesday, I was driving back to the airport with my family to come home, when something really bizarre happened. We were travelling down the freeway, just pulled out to go past a truck (farm-truck sized, not a semi-trailer), when a car-sized mass of metal fell off it. It was something like an industrial air-conditioner, but from where I was sitting, it was just a mass of spinning metal, like something out of a movie (one friend described it as “holidays by Michael Bay”). Somehow, and I’m really don’t know how, the part of it nearest us bounced high enough to clear the car, and there wasn’t even a scratch. We pulled over the check, and I was just thanking God that we’d changed lanes when we had, and that we remained unharmed. I had all kinds of thoughts about what could’ve happened if we’d had something that size land on the windscreen... All this has drilled home that while I feel that I haven’t provided as well for the family as I could’ve done (like by pursuing an expensive legal case), I shouldn’t even consider that I have proper control over things. I get to live life, and make decisions based on what I feel is right at the time. But I’m not going to get everything right, and there will be things that feel like disasters, some which could’ve been in my control and some which are very much beyond my control. The case feels like something I could’ve pursued differently, a disaster that could’ve been avoided in some way. Gran dying is lousy of course. An accident on the freeway would have been awful. I need to recognise that the worst disasters are ones that I can’t affect, and that I need to look at things in context – perhaps seeing everything that happens as a migration instead. Life is never the same from one day to the next. Every event has a before and an after – sometimes it’s clearly positive, sometimes it’s not. I remember good events in my life (such as my wedding), and bad (such as the loss of my father when I was ten, or the back injury I had eight years ago). I’m not suggesting that I know how to view everything from the “God works all things for good” perspective, but I am trying to look at last week as a migration of sorts. Those things are behind me now, and the future is in God’s hands. Hopefully I’ve learned things, and will be able to live accordingly. I’ve come through this time now, and even though I’ll miss Gran, I’ll see her again one day, and the future is bright.

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• Scheduling thread tiles with C++ AMP

  - by Daniel Moth

  This post assumes you are totally comfortable with, what some of us call, the simple model of C++ AMP, i.e. you could write your own matrix multiplication. We are now ready to explore the tiled model, which builds on top of the non-tiled one. Tiling the extent We know that when we pass a grid (which is just an extent under the covers) to the parallel_for_each call, it determines the number of threads to schedule and their index values (including dimensionality). For the single-, two-, and three- dimensional cases you can go a step further and subdivide the threads into what we call tiles of threads (others may call them thread groups). So here is a single-dimensional example: extent<1> e(20); // 20 units in a single dimension with indices from 0-19 grid<1> g(e);      // same as extent tiled_grid<4> tg = g.tile<4>(); …on the 3rd line we subdivided the single-dimensional space into 5 single-dimensional tiles each having 4 elements, and we captured that result in a concurrency::tiled_grid (a new class in amp.h). Let's move on swiftly to another example, in pictures, this time 2-dimensional: So we start on the left with a grid of a 2-dimensional extent which has 8*6=48 threads. We then have two different examples of tiling. In the first case, in the middle, we subdivide the 48 threads into tiles where each has 4*3=12 threads, hence we have 2*2=4 tiles. In the second example, on the right, we subdivide the original input into tiles where each has 2*2=4 threads, hence we have 4*3=12 tiles. Notice how you can play with the tile size and achieve different number of tiles. The numbers you pick must be such that the original total number of threads (in our example 48), remains the same, and every tile must have the same size. Of course, you still have no clue why you would do that, but stick with me. First, we should see how we can use this tiled_grid, since the parallel_for_each function that we know expects a grid. Tiled parallel_for_each and tiled_index It turns out that we have additional overloads of parallel_for_each that accept a tiled_grid instead of a grid. However, those overloads, also expect that the lambda you pass in accepts a concurrency::tiled_index (new in amp.h), not an index<N>. So how is a tiled_index different to an index? A tiled_index object, can have only 1 or 2 or 3 dimensions (matching exactly the tiled_grid), and consists of 4 index objects that are accessible via properties: global, local, tile_origin, and tile. The global index is the same as the index we know and love: the global thread ID. The local index is the local thread ID within the tile. The tile_origin index returns the global index of the thread that is at position 0,0 of this tile, and the tile index is the position of the tile in relation to the overall grid. Confused? Here is an example accompanied by a picture that hopefully clarifies things: array_view<int, 2> data(8, 6, p_my_data); parallel_for_each(data.grid.tile<2,2>(), [=] (tiled_index<2,2> t_idx) restrict(direct3d) { /* todo */ }); Given the code above and the picture on the right, what are the values of each of the 4 index objects that the t_idx variables exposes, when the lambda is executed by T (highlighted in the picture on the right)? If you can't work it out yourselves, the solution follows: t_idx.global       = index<2> (6,3) t_idx.local          = index<2> (0,1) t_idx.tile_origin = index<2> (6,2) t_idx.tile             = index<2> (3,1) Don't move on until you are comfortable with this… the picture really helps, so use it. Tiled Matrix Multiplication Example – part 1 Let's paste here the C++ AMP matrix multiplication example, bolding the lines we are going to change (can you guess what the changes will be?) 01: void MatrixMultiplyTiled_Part1(vector<float>& vC, const vector<float>& vA, const vector<float>& vB, int M, int N, int W) 02: { 03: 04: array_view<const float,2> a(M, W, vA); 05: array_view<const float,2> b(W, N, vB); 06: array_view<writeonly<float>,2> c(M, N, vC); 07: parallel_for_each(c.grid, 08: [=](index<2> idx) restrict(direct3d) { 09: 10: int row = idx[0]; int col = idx[1]; 11: float sum = 0.0f; 12: for(int i = 0; i < W; i++) 13: sum += a(row, i) * b(i, col); 14: c[idx] = sum; 15: }); 16: } To turn this into a tiled example, first we need to decide our tile size. Let's say we want each tile to be 16*16 (which assumes that we'll have at least 256 threads to process, and that c.grid.extent.size() is divisible by 256, and moreover that c.grid.extent[0] and c.grid.extent[1] are divisible by 16). So we insert at line 03 the tile size (which must be a compile time constant). 03: static const int TS = 16; ...then we need to tile the grid to have tiles where each one has 16*16 threads, so we change line 07 to be as follows 07: parallel_for_each(c.grid.tile<TS,TS>(), ...that means that our index now has to be a tiled_index with the same characteristics as the tiled_grid, so we change line 08 08: [=](tiled_index<TS, TS> t_idx) restrict(direct3d) { ...which means, without changing our core algorithm, we need to be using the global index that the tiled_index gives us access to, so we insert line 09 as follows 09: index<2> idx = t_idx.global; ...and now this code just works and it is tiled! Closing thoughts on part 1 The process we followed just shows the mechanical transformation that can take place from the simple model to the tiled model (think of this as step 1). In fact, when we wrote the matrix multiplication example originally, the compiler was doing this mechanical transformation under the covers for us (and it has additional smarts to deal with the cases where the total number of threads scheduled cannot be divisible by the tile size). The point is that the thread scheduling is always tiled, even when you use the non-tiled model. But with this mechanical transformation, we haven't gained anything… Hint: our goal with explicitly using the tiled model is to gain even more performance. In the next post, we'll evolve this further (beyond what the compiler can automatically do for us, in this first release), so you can see the full usage of the tiled model and its benefits… Comments about this post by Daniel Moth welcome at the original blog.

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• Best Practices - which domain types should be used to run applications

  - by jsavit

  This post is one of a series of "best practices" notes for Oracle VM Server for SPARC (formerly named Logical Domains) One question that frequently comes up is "which types of domain should I use to run applications?" There used to be a simple answer in most cases: "only run applications in guest domains", but enhancements to T-series servers, Oracle VM Server for SPARC and the advent of SPARC SuperCluster have made this question more interesting and worth qualifying differently. This article reviews the relevant concepts and provides suggestions on where to deploy applications in a logical domains environment. Review: division of labor and types of domain Oracle VM Server for SPARC offloads many functions from the hypervisor to domains (also called virtual machines). This is a modern alternative to using a "thick" hypervisor that provides all virtualization functions, as in traditional VM designs, This permits a simpler hypervisor design, which enhances reliability, and security. It also reduces single points of failure by assigning responsibilities to multiple system components, which further improves reliability and security. In this architecture, management and I/O functionality are provided within domains. Oracle VM Server for SPARC does this by defining the following types of domain, each with their own roles: Control domain - management control point for the server, used to configure domains and manage resources. It is the first domain to boot on a power-up, is an I/O domain, and is usually a service domain as well. I/O domain - has been assigned physical I/O devices: a PCIe root complex, a PCI device, or a SR-IOV (single-root I/O Virtualization) function. It has native performance and functionality for the devices it owns, unmediated by any virtualization layer. Service domain - provides virtual network and disk devices to guest domains. Guest domain - a domain whose devices are all virtual rather than physical: virtual network and disk devices provided by one or more service domains. In common practice, this is where applications are run. Typical deployment A service domain is generally also an I/O domain: otherwise it wouldn't have access to physical device "backends" to offer to its clients. Similarly, an I/O domain is also typically a service domain in order to leverage the available PCI busses. Control domains must be I/O domains, because they boot up first on the server and require physical I/O. It's typical for the control domain to also be a service domain too so it doesn't "waste" the I/O resources it uses. A simple configuration consists of a control domain, which is also the one I/O and service domain, and some number of guest domains using virtual I/O. In production, customers typically use multiple domains with I/O and service roles to eliminate single points of failure: guest domains have virtual disk and virtual devices provisioned from more than one service domain, so failure of a service domain or I/O path or device doesn't result in an application outage. This is also used for "rolling upgrades" in which service domains are upgraded one at a time while their guests continue to operate without disruption. (It should be noted that resiliency to I/O device failures can also be provided by the single control domain, using multi-path I/O) In this type of deployment, control, I/O, and service domains are used for virtualization infrastructure, while applications run in guest domains. Changing application deployment patterns The above model has been widely and successfully used, but more configuration options are available now. Servers got bigger than the original T2000 class machines with 2 I/O busses, so there is more I/O capacity that can be used for applications. Increased T-series server capacity made it attractive to run more vertical applications, such as databases, with higher resource requirements than the "light" applications originally seen. This made it attractive to run applications in I/O domains so they could get bare-metal native I/O performance. This is leveraged by the SPARC SuperCluster engineered system, announced a year ago at Oracle OpenWorld. In SPARC SuperCluster, I/O domains are used for high performance applications, with native I/O performance for disk and network and optimized access to the Infiniband fabric. Another technical enhancement is the introduction of Direct I/O (DIO) and Single Root I/O Virtualization (SR-IOV), which make it possible to give domains direct connections and native I/O performance for selected I/O devices. A domain with either a DIO or SR-IOV device is an I/O domain. In summary: not all I/O domains own PCI complexes, and there are increasingly more I/O domains that are not service domains. They use their I/O connectivity for performance for their own applications. However, there are some limitations and considerations: at this time, a domain using physical I/O cannot be live-migrated to another server. There is also a need to plan for security and introducing unneeded dependencies: if an I/O domain is also a service domain providing virtual I/O go guests, it has the ability to affect the correct operation of its client guest domains. This is even more relevant for the control domain. where the ldm has to be protected from unauthorized (or even mistaken) use that would affect other domains. As a general rule, running applications in the service domain or the control domain should be avoided. To recap: Guest domains with virtual I/O still provide the greatest operational flexibility, including features like live migration. I/O domains can be used for applications with high performance requirements. This is used to great effect in SPARC SuperCluster and in general T4 deployments. Direct I/O (DIO) and Single Root I/O Virtualization (SR-IOV) make this more attractive by giving direct I/O access to more domains. Service domains should in general not be used for applications, because compromised security in the domain, or an outage, can affect other domains that depend on it. This concern can be mitigated by providing guests' their virtual I/O from more than one service domain, so an interruption of service in the service domain does not cause an application outage. The control domain should in general not be used to run applications, for the same reason. SPARC SuperCluster use the control domain for applications, but it is an exception: it's not a general purpose environment; it's an engineered system with specifically configured applications and optimization for optimal performance. These are recommended "best practices" based on conversations with a number of Oracle architects. Keep in mind that "one size does not fit all", so you should evaluate these practices in the context of your own requirements. Summary Higher capacity T-series servers have made it more attractive to use them for applications with high resource requirements. New deployment models permit native I/O performance for demanding applications by running them in I/O domains with direct access to their devices. This is leveraged in SPARC SuperCluster, and can be leveraged in T-series servers to provision high-performance applications running in domains. Carefully planned, this can be used to provide higher performance for critical applications.

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• D2K to OA Framework Transition

  - by PRajkumar

  What is the difference between D2K form and OA Framework? It is a very innocent but important question for someone that desires to make transition from D2K to OA Framework. I hope you have already read and implemented OA Framework Getting Started. I will re-visit my own experience of implementing HelloWorld program in "OA Framework". When I implemented HelloWorld a year ago, I had no clue as to what I was doing & why I was doing those steps. I merely copied the steps from Oracle Tutorial without understanding them. Hence in this blog, I will try to explain in simple manner the meaning of OA Framework HelloWorld Program and compare the steps to D2K form [where possible]. To keep things simple, only basics will be discussed. Following key Steps were needed for HelloWorld Step 1 Create a new Workspace and a new Project as dictated by Oracle's tutorial. When defining project, you will specify a default package, which in this case was oracle.apps.ak.hello This means the following: - ak is the short name of the Application in Oracle           [means fnd_applications.short_name] hello is the name of your project Step 2 Next, you will create a OA Page within hello project Think OA Page as the fmx file itself in D2K. I am saying so because this page gets attached to the form function. This page will be created within hello project, hence the package name oracle.apps.ak.hello.webui Note the webui, it is a convention to have page in webui, means this page represents the Web User Interface You will assign the default AM [OAApplicationModule]. Think of AM "Connection Manager" and "Transaction State Manager" for your page          I can't co-relate this to anything in D2k, as there is no concept of Connection Pooling and that D2k is not stateless. Reason being that as soon as you kick off a D2K Form, it connects to a single session of Oracle and sticks to that single Oracle database session. So is not the case in OAF, hence AM is needed. Step 3 You create Region within the Page. ·         Region is what will store your fields. Text input fields will be of type messageTextInput. Think of Canvas in D2K. You can have nested regions. Stacked Canvas in D2K comes the closest to this component of OA Framework Step 4 Add a button to one of the nested regions The itemStyle should be submitButton, in case you want the page to be submitted when this button is clicked There is no WHEN-BUTTON-PRESSED trigger in OAF. In Framework, you will add a controller java code to handle events like Form Submit button clicks. JDeveloper generates the default code for you. Primarily two functions [should I call methods] will be created processRequest [for UI Rendering Handling] and processFormRequest          Think of processRequest as WHEN-NEW-FORM-INSTANCE, though processRequest is very restrictive. Note What is the difference between processRequest and processFormRequest? These two methods are available in the Default Controller class that gets created. processFormRequest This method is commonly used to react/respond to the event that has taken place, for example click of a button. Some examples are if(oapagecontext.getParameter("Cancel") != null) (Do your processing for Cancellation/ Rollback) if(oapagecontext.getParameter("Submit") != null) (Do your validations and commit here) if(oapagecontext.getParameter("Update") != null) (Do your validations and commit here) In the above three examples, you could be calling oapagecontext.forwardImmediately to re-direct the page navigation to some other page if needed. processRequest In this method, usually page rendering related code is written. Effectively, each GUI component is a bean that gets initialised during processRequest. Those who are familiar with D2K forms, something like pre-query may be written in this method. Step 5 In the controller to access the value in field "HelloName" the command is String userContent = pageContext.getParameter("HelloName"); In D2k, we used :block.field. In OAFramework, at submission of page, all the field values get passed into to OAPageContext object. Use getParameter to access the field value To set the value of the field, use OAMessageTextInputBean field HelloName = (OAMessageTextInputBean)webBean.findChildRecursive("HelloName"); fieldHelloName.setText(pageContext,"Setting the default value" ); Note when setting field value in controller: Note 1. Do not set the value in processFormRequest Note 2. If the field comes from View Object, then do not use setText in controller Note 3. For control fields [that are not based on View Objects], you can use setText to assign values in processRequest method Lets take some notes to expand beyond the HelloWorld Project Note 1 In D2K-forms we sort of created a Window, attached to Canvas, and then fields within that Canvas. However in OA Framework, think of Page being fmx/Window, think of Region being a Canvas, and fields being within Regions. This is not a formal/accurate understanding of analogy between D2k and Framework, but is close to being logical. Note 2 In D2k, your Forms fmb file was compiled to fmx. It was fmx file that was deployed on mid-tier. In case of OAF, your OA Page is nothing but a XML file. We call this MDS [meta data]. Whatever name you give to "Page" in OAF, an XML file of the same name gets created. This xml file must then be loaded into database by using XML Importer command. Note 3 Apart from MDS XML file, almost everything else is merely deployed to your mid-tier. Usually this is underneath $JAVA_TOP/oracle/apps/../.. All java files will go underneath java top/oracle/apps/../.. etc. Note 4 When building tutorial, ignore the steps for setting "Attribute Sets". These are not mandatory. Oracle might just have developed their tutorials without including these. Think of these like Visual Attributes of D2K forms Note 5 Controller is where you will write any java code in OA Framework. You can create a Controller per Page or have a different Controller for each of the Regions with the same Page. Note 6 In the method processFormRequest of the Controller, you can access the values of the page by using notation pageContext.getParameter("<fieldname here>"). This method processFormRequest is executed when the OAF Screen/Page is submitted by click of a button. Note 7 Inside the controller, all the Database Related interactions for example interaction with View Objects happen via Application Module. But why so? Because Application Module Manages the transaction state of the Application. OAApplicationModuleImpl oaapplicationmoduleimpl = OAApplicationModuleImpl)oapagecontext.getApplicationModule(oawebbean); OADBTransaction oadbtransaction = OADBTransaction)oaapplicationmoduleimpl.getDBTransaction(); Note 8 In D2K, we have control block or a block based on database view. Similarly, in OA Framework, if the field does not have view Object attached, then it is like a control field. Hence in HelloWorld example, field HelloName is a control field [in D2K terminology]. A view Object can either be based on a view/table, synonym or on a SQL statement. Note 9 I wish to access the fields in multi record block that is based on view Object. Can I do this in Controller? Sure you can. To traverse through those records, do the below ·         Get the reference to the View Object using (OAViewObject)oapagecontext.getApplicationModule(oawebbean).findViewObject("VO Name Here") ·         Loop through the records in View Objects using count returned from oaviewobject.getFetchedRowCount() ·         For each record, fetch the value of the fields within the loop as oracle.jbo.Row row = oaviewobject.getRowAtRangeIndex(loop index here); (String)row.getAttribute("Column name of VO here ");

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• Recursion in the form of a Recursive Func&lt;T, T&gt;

  - by ToStringTheory

  I gotta admit, I am kind of surprised that I didn’t realize I could do this sooner.  I recently had a problem which required a recursive function call to come up with the answer.  After some time messing around with a recursive method, and creating an API that I was not happy with, I was able to create an API that I enjoy, and seems intuitive. Introduction To bring it to a simple example, consider the summation to n: A mathematically identical formula is: In a .NET function, this can be represented by a function: Func<int, int> summation = x => x*(x+1)/2 Calling summation with an input integer will yield the summation to that number: var sum10 = summation(4); //sum10 would be equal to 10 But what if I wanted to get a second level summation…  First some to n, and then use that argument as the input to the same function, to find the second level summation: So as an easy example, calculate the summation to 3, which yields 6.  Then calculate the summation to 6 which yields 21. Represented as a mathematical formula - So what if I wanted to represent this as .NET functions.  I can always do: //using the summation formula from above var sum3 = summation(3); //sets sum3 to 6 var sum3_2 = summation(sum3); //sets sum3 to 21 I could always create a while loop to perform the calculations too: Func<int, int> summation = x => x*(x+1)/2; //for the interests of a smaller example, using shorthand int sumResultTo = 3; int level = 2; while(level-- > 0) { sumResultTo = summation(sumResultTo); } //sumResultTo is equal to 21 now. Or express it as a for-loop, method calls, etc…  I really didn’t like any of the options that I tried.  Then it dawned on me – since I was using a Func<T, T> anyways, why not use the Func’s output from one call as the input as another directly. Some Code So, I decided that I wanted a recursion class.  Something that I would be generic and reusable in case I ever wanted to do something like this again. It is limited to only the Func<T1, T2> level of Func, and T1 must be the same as T2. The first thing in this class is a private field for the function: private readonly Func<T, T> _functionToRecurse; So, I since I want the function to be unchangeable, I have defined it as readonly.  Therefore my constructor looks like: public Recursion(Func<T, T> functionToRecurse) { if (functionToRecurse == null) { throw new ArgumentNullException("functionToRecurse", "The function to recurse can not be null"); } _functionToRecurse = functionToRecurse; } Simple enough.  If you have any questions, feel free to post them in the comments, and I will be sure to answer them. Next, I want enough. If be able to get the result of a function dependent on how many levels of recursion: private Func<T, T> GetXLevel(int level) { if (level < 1) { throw new ArgumentOutOfRangeException("level", level, "The level of recursion must be greater than 0"); } if (level == 1) return _functionToRecurse; return _GetXLevel(level - 1, _functionToRecurse); } So, if you pass in 1 for the level, you get just the Func<T,T> back.  If you say that you want to go deeper down the rabbit hole, it calls a method which accepts the level it is at, and the function which it needs to use to recurse further: private Func<T, T> _GetXLevel(int level, Func<T, T> prevFunc) { if (level == 1) return y => prevFunc(_functionToRecurse(y)); return _GetXLevel(level - 1, y => prevFunc(_functionToRecurse(y))); } That is really all that is needed for this class. If I exposed the GetXLevel function publicly, I could use that to get the function for a level, and pass in the argument..  But I wanted something better.  So, I used the ‘this’ array operator for the class: public Func<T,T> this[int level] { get { if (level < 1) { throw new ArgumentOutOfRangeException("level", level, "The level of recursion must be greater than 0"); } return this.GetXLevel(level); } } So, using the same example above of finding the second recursion of the summation of 3: var summator = new Recursion<int>(x => (x * (x + 1)) / 2); var sum_3_level2 = summator[2](3); //yields 21 You can even find just store the delegate to the second level summation, and use it multiple times: var summator = new Recursion<int>(x => (x * (x + 1)) / 2); var sum_level2 = summator[2]; var sum_3_level2 = sum_level2(3); //yields 21 var sum_4_level2 = sum_level2(4); //yields 55 var sum_5_level2 = sum_level2(5); //yields 120 Full Code Don’t think I was just going to hold off on the full file together and make you do the hard work…  Copy this into a new class file: public class Recursion<T> { private readonly Func<T, T> _functionToRecurse; public Recursion(Func<T, T> functionToRecurse) { if (functionToRecurse == null) { throw new ArgumentNullException("functionToRecurse", "The function to recurse can not be null"); } _functionToRecurse = functionToRecurse; } public Func<T,T> this[int level] { get { if (level < 1) { throw new ArgumentOutOfRangeException("level", level, "The level of recursion must be greater than 0"); } return this.GetXLevel(level); } } private Func<T, T> GetXLevel(int level) { if (level < 1) { throw new ArgumentOutOfRangeException("level", level, "The level of recursion must be greater than 0"); } if (level == 1) return _functionToRecurse; return _GetXLevel(level - 1, _functionToRecurse); } private Func<T, T> _GetXLevel(int level, Func<T, T> prevFunc) { if (level == 1) return y => prevFunc(_functionToRecurse(y)); return _GetXLevel(level - 1, y => prevFunc(_functionToRecurse(y))); } } Conclusion The great thing about this class, is that it can be used with any function with same input/output parameters.  I strived to find an implementation that I found clean and useful, and I finally settled on this.  If you have feedback – good or bad, I would love to hear it!

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• Computer Networks UNISA - Chap 10 &ndash; In Depth TCP/IP Networking

  - by MarkPearl

  After reading this section you should be able to Understand methods of network design unique to TCP/IP networks, including subnetting, CIDR, and address translation Explain the differences between public and private TCP/IP networks Describe protocols used between mail clients and mail servers, including SMTP, POP3, and IMAP4 Employ multiple TCP/IP utilities for network discovery and troubleshooting Designing TCP/IP-Based Networks The following sections explain how network and host information in an IPv4 address can be manipulated to subdivide networks into smaller segments. Subnetting Subnetting separates a network into multiple logically defined segments, or subnets. Networks are commonly subnetted according to geographic locations, departmental boundaries, or technology types. A network administrator might separate traffic to accomplish the following… Enhance security Improve performance Simplify troubleshooting The challenges of Classful Addressing in IPv4 (No subnetting) The simplest type of IPv4 is known as classful addressing (which was the Class A, Class B & Class C network addresses). Classful addressing has the following limitations. Restriction in the number of usable IPv4 addresses (class C would be limited to 254 addresses) Difficult to separate traffic from various parts of a network Because of the above reasons, subnetting was introduced. IPv4 Subnet Masks Subnetting depends on the use of subnet masks to identify how a network is subdivided. A subnet mask indicates where network information is located in an IPv4 address. The 1 in a subnet mask indicates that corresponding bits in the IPv4 address contain network information (likewise 0 indicates the opposite) Each network class is associated with a default subnet mask… Class A = 255.0.0.0 Class B = 255.255.0.0 Class C = 255.255.255.0 An example of calculating  the network ID for a particular device with a subnet mask is shown below.. IP Address = 199.34.89.127 Subnet Mask = 255.255.255.0 Resultant Network ID = 199.34.89.0 IPv4 Subnetting Techniques Subnetting breaks the rules of classful IPv4 addressing. Read page 490 for a detailed explanation Calculating IPv4 Subnets Read page 491 – 494 for an explanation Important… Subnetting only applies to the devices internal to your network. Everything external looks at the class of the IP address instead of the subnet network ID. This way, traffic directed to your network externally still knows where to go, and once it has entered your internal network it can then be prioritized and segmented. CIDR (classless Interdomain Routing) CIDR is also known as classless routing or supernetting. In CIDR conventional network class distinctions do not exist, a subnet boundary can move to the left, therefore generating more usable IP addresses on your network. A subnet created by moving the subnet boundary to the left is known as a supernet. With CIDR also came new shorthand for denoting the position of subnet boundaries known as CIDR notation or slash notation. CIDR notation takes the form of the network ID followed by a forward slash (/) followed by the number of bits that are used for the extended network prefix. To take advantage of classless routing, your networks routers must be able to interpret IP addresses that don;t adhere to conventional network class parameters. Routers that rely on older routing protocols (i.e. RIP) are not capable of interpreting classless IP addresses. Internet Gateways Gateways are a combination of software and hardware that enable two different network segments to exchange data. A gateway facilitates communication between different networks or subnets. Because on device cannot send data directly to a device on another subnet, a gateway must intercede and hand off the information. Every device on a TCP/IP based network has a default gateway (a gateway that first interprets its outbound requests to other subnets, and then interprets its inbound requests from other subnets). The internet contains a vast number of routers and gateways. If each gateway had to track addressing information for every other gateway on the Internet, it would be overtaxed. Instead, each handles only a relatively small amount of addressing information, which it uses to forward data to another gateway that knows more about the data’s destination. The gateways that make up the internet backbone are called core gateways. Address Translation An organizations default gateway can also be used to “hide” the organizations internal IP addresses and keep them from being recognized on a public network. A public network is one that any user may access with little or no restrictions. On private networks, hiding IP addresses allows network managers more flexibility in assigning addresses. Clients behind a gateway may use any IP addressing scheme, regardless of whether it is recognized as legitimate by the Internet authorities but as soon as those devices need to go on the internet, they must have legitimate IP addresses to exchange data. When a clients transmission reaches the default gateway, the gateway opens the IP datagram and replaces the client’s private IP address with an Internet recognized IP address. This process is known as NAT (Network Address Translation). TCP/IP Mail Services All Internet mail services rely on the same principles of mail delivery, storage, and pickup, though they may use different types of software to accomplish these functions. Email servers and clients communicate through special TCP/IP application layer protocols. These protocols, all of which operate on a variety of operating systems are discussed below… SMTP (Simple Mail transfer Protocol) The protocol responsible for moving messages from one mail server to another over TCP/IP based networks. SMTP belongs to the application layer of the ODI model and relies on TCP as its transport protocol. Operates from port 25 on the SMTP server Simple sub-protocol, incapable of doing anything more than transporting mail or holding it in a queue MIME (Multipurpose Internet Mail Extensions) The standard message format specified by SMTP allows for lines that contain no more than 1000 ascii characters meaning if you relied solely on SMTP you would have very short messages and nothing like pictures included in an email. MIME us a standard for encoding and interpreting binary files, images, video, and non-ascii character sets within an email message. MIME identifies each element of a mail message according to content type. MIME does not replace SMTP but works in conjunction with it. Most modern email clients and servers support MIME POP (Post Office Protocol) POP is an application layer protocol used to retrieve messages from a mail server POP3 relies on TCP and operates over port 110 With POP3 mail is delivered and stored on a mail server until it is downloaded by a user Disadvantage of POP3 is that it typically does not allow users to save their messages on the server because of this IMAP is sometimes used IMAP (Internet Message Access Protocol) IMAP is a retrieval protocol that was developed as a more sophisticated alternative to POP3 The single biggest advantage IMAP4 has over POP3 is that users can store messages on the mail server, rather than having to continually download them Users can retrieve all or only a portion of any mail message Users can review their messages and delete them while the messages remain on the server Users can create sophisticated methods of organizing messages on the server Users can share a mailbox in a central location Disadvantages of IMAP are typically related to the fact that it requires more storage space on the server. Additional TCP/IP Utilities Nearly all TCP/IP utilities can be accessed from the command prompt on any type of server or client running TCP/IP. The syntaxt may differ depending on the OS of the client. Below is a list of additional TCP/IP utilities – research their use on your own! Ipconfig (Windows) & Ifconfig (Linux) Netstat Nbtstat Hostname, Host & Nslookup Dig (Linux) Whois (Linux) Traceroute (Tracert) Mtr (my traceroute) Route

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• Passing a parameter so that it cannot be changed – C#

  - by nmarun

  I read this requirement of not allowing a user to change the value of a property passed as a parameter to a method. In C++, as far as I could recall (it’s been over 10 yrs, so I had to refresh memory), you can pass ‘const’ to a function parameter and this ensures that the parameter cannot be changed inside the scope of the function. There’s no such direct way of doing this in C#, but that does not mean it cannot be done!! Ok, so this ‘not-so-direct’ technique depends on the type of the parameter – a simple property or a collection. Parameter as a simple property: This is quite easy (and you might have guessed it already). Bulent Ozkir clearly explains how this can be done here. Parameter as a collection property: Obviously the above does not work if the parameter is a collection of some type. Let’s dig-in. Suppose I need to create a collection of type KeyTitle as defined below. 1: public class KeyTitle 2: { 3: public int Key { get; set; } 4: public string Title { get; set; } 5: } My class is declared as below: 1: public class Class1 2: { 3: public Class1() 4: { 5: MyKeyTitleList = new List<KeyTitle>(); 6: } 7: 8: public List<KeyTitle> MyKeyTitleList { get; set; } 9: public ReadOnlyCollection<KeyTitle> ReadonlyKeyTitleCollection 10: { 11: // .AsReadOnly creates a ReadOnlyCollection<> type 12: get { return MyKeyTitleList.AsReadOnly(); } 13: } 14: } See the .AsReadOnly() method used in the second property? As MSDN says it: “Returns a read-only IList<T> wrapper for the current collection.” Knowing this, I can implement my code as: 1: public static void Main() 2: { 3: Class1 class1 = new Class1(); 4: class1.MyKeyTitleList.Add(new KeyTitle { Key = 1, Title = "abc" }); 5: class1.MyKeyTitleList.Add(new KeyTitle { Key = 2, Title = "def" }); 6: class1.MyKeyTitleList.Add(new KeyTitle { Key = 3, Title = "ghi" }); 7: class1.MyKeyTitleList.Add(new KeyTitle { Key = 4, Title = "jkl" }); 8:  9: TryToModifyCollection(class1.MyKeyTitleList.AsReadOnly()); 10:  11: Console.ReadLine(); 12: } 13:  14: private static void TryToModifyCollection(ReadOnlyCollection<KeyTitle> readOnlyCollection) 15: { 16: // can only read 17: for (int i = 0; i < readOnlyCollection.Count; i++) 18: { 19: Console.WriteLine("{0} - {1}", readOnlyCollection[i].Key, readOnlyCollection[i].Title); 20: } 21: // Add() - not allowed 22: // even the indexer does not have a setter 23: } The output is as expected: The below image shows two things. In the first line, I’ve tried to access an element in my read-only collection through an indexer. It shows that the ReadOnlyCollection<> does not have a setter on the indexer. The second line tells that there’s no ‘Add()’ method for this type of collection. The capture below shows there’s no ‘Remove()’ method either, there-by eliminating all ways of modifying a collection. Mission accomplished… right? Now, even if you have a collection of different type, all you need to do is to somehow cast (used loosely) it to a List<> and then do a .AsReadOnly() to get a ReadOnlyCollection of your custom collection type. As an example, if you have an IDictionary<int, string>, you can create a List<T> of this type with a wrapper class (KeyTitle in our case). 1: public IDictionary<int, string> MyDictionary { get; set; } 2:  3: public ReadOnlyCollection<KeyTitle> ReadonlyDictionary 4: { 5: get 6: { 7: return (from item in MyDictionary 8: select new KeyTitle 9: { 10: Key = item.Key, 11: Title = item.Value, 12: }).ToList().AsReadOnly(); 13: } 14: } Cool huh? Just one thing you need to know about the .AsReadOnly() method is that the only way to modify your ReadOnlyCollection<> is to modify the original collection. So doing: 1: public static void Main() 2: { 3: Class1 class1 = new Class1(); 4: class1.MyKeyTitleList.Add(new KeyTitle { Key = 1, Title = "abc" }); 5: class1.MyKeyTitleList.Add(new KeyTitle { Key = 2, Title = "def" }); 6: class1.MyKeyTitleList.Add(new KeyTitle { Key = 3, Title = "ghi" }); 7: class1.MyKeyTitleList.Add(new KeyTitle { Key = 4, Title = "jkl" }); 8: TryToModifyCollection(class1.MyKeyTitleList.AsReadOnly()); 9:  10: Console.WriteLine(); 11:  12: class1.MyKeyTitleList.Add(new KeyTitle { Key = 5, Title = "mno" }); 13: class1.MyKeyTitleList[2] = new KeyTitle{Key = 3, Title = "GHI"}; 14: TryToModifyCollection(class1.MyKeyTitleList.AsReadOnly()); 15:  16: Console.ReadLine(); 17: } Gives me the output of: See that the second element’s Title is changed to upper-case and the fifth element also gets displayed even though we’re still looping through the same ReadOnlyCollection<KeyTitle>. Verdict: Now you know of a way to implement ‘Method(const param1)’ in your code!

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• Lambda&rsquo;s for .NET made easy&hellip;

  - by mbcrump

  The purpose of my blog is to explain things for a beginner to intermediate c# programmer. I’ve seen several blog post that use lambda expressions always assuming the audience is familiar with them. The purpose of this post is to make them simple and easily understood. Let’s begin with a definition. A lambda expression is an anonymous function that can contain expressions and statements, and can be used to create delegates or expression tree types. So anonymous function… delegates or expression tree types? I don’t get it??? Confused yet?   Lets break this into a few definitions and jump right into the code. anonymous function – is an "inline" statement or expression that can be used wherever a delegate type is expected. delegate - is a type that references a method. Once a delegate is assigned a method, it behaves exactly like that method. The delegate method can be used like any other method, with parameters and a return value. Expression trees - represent code in a tree-like data structure, where each node is an expression, for example, a method call or a binary operation such as x < y.   Don’t worry if this still sounds confusing, lets jump right into the code with a simple 3 line program. We are going to use a Function Delegate (all you need to remember is that this delegate returns a value.) Lambda expressions are used most commonly with the Func and Action delegates, so you will see an example of both of these. Lambda Expression 3 lines. using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace ConsoleApplication7 {     class Program     {          static void Main(string[] args)         {             Func<int, int> myfunc = x => x *x;             Console.WriteLine(myfunc(6).ToString());             Console.ReadLine();         }       } } Is equivalent to Old way of doing it. using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace ConsoleApplication7 {     class Program     {          static void Main(string[] args)         {               Console.WriteLine(myFunc(6).ToString());             Console.ReadLine();         }            static int myFunc(int x)          {              return x * x;            }       } } In the example, there is a single parameter, x, and the expression is x*x. I’m going to stop here to make sure you are still with me. A lambda expression is an unnamed method written in place of a delegate instance. In other words, the compiler converts the lambda expression to either a : A delegate instance An expression tree All lambda have the following form: (parameters) => expression or statement block Now look back to the ones we have created. It should start to sink in. Don’t get stuck on the => form, use it as an identifier of a lambda. A Lamba expression can also be written in the following form: Lambda Expression. using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace ConsoleApplication7 {     class Program     {          static void Main(string[] args)         {             Func<int, int> myFunc = x =>             {                 return x * x;             };               Console.WriteLine(myFunc(6).ToString());             Console.ReadLine();         }       } } This form may be easier to read but consumes more space. Lets try an Action delegate – this delegate does not return a value. Action Delegate example. using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace ConsoleApplication7 {     class Program     {          static void Main(string[] args)         {             Action<string> myAction = (string x) => { Console.WriteLine(x); };             myAction("michael has made this so easy");                                   Console.ReadLine();         }       } } Lambdas can also capture outer variables (such as the example below) A lambda expression can reference the local variables and parameters of the method in which it’s defined. Outer variables referenced by a lambda expression are called captured variables. Capturing Outer Variables using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace ConsoleApplication7 {     class Program     {          static void Main(string[] args)         {             string mike = "Michael";             Action<string> myAction = (string x) => {                 Console.WriteLine("{0}{1}", mike, x);          };             myAction(" has made this so easy");                                   Console.ReadLine();         }       } } Lamba’s can also with a strongly typed list to loop through a collection.   Used w a strongly typed list. using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace ConsoleApplication7 {     class Program     {          static void Main(string[] args)         {             List<string> list = new List<string>() { "1", "2", "3", "4" };             list.ForEach(s => Console.WriteLine(s));             Console.ReadLine();         }       } } Outputs: 1 2 3 4 I think this will get you started with Lambda’s, as always consult the MSDN documentation for more information. Still confused? Hopefully you are not.

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• ANTS CLR and Memory Profiler In Depth Review (Part 2 of 2 &ndash; Memory Profiler)

  - by ToStringTheory

  One of the things that people might not know about me, is my obsession to make my code as efficient as possible. Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind… In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve. One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well. In this review, I am going to cover some of the features of the ANTS memory profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program. I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction – Part 2 In my last post, I reviewed the feature packed Red Gate ANTS Performance Profiler.  Separate from the Red Gate Performance Profiler is the Red Gate ANTS Memory Profiler – a simple, easy to use utility for checking how your application is handling memory management…  A tool that I wish I had had many times in the past.  This post will be focusing on the ANTS Memory Profiler and its tool set. The memory profiler has a large assortment of features just like the Performance Profiler, with the new session looking nearly exactly alike: ANTS Memory Profiler Memory profiling is not something that I have to do very often…  In the past, the few cases I’ve had to find a memory leak in an application I have usually just had to trace the code of the operations being performed to look for oddities…  Sadly, I have come across more undisposed/non-using’ed IDisposable objects, usually from ADO.Net than I would like to ever see.  Support is not fun, however using ANTS Memory Profiler makes this task easier.  For this round of testing, I am going to use the same code from my previous example, using the WPF application. This time, I will choose the ‘Profile Memory’ option from the ANTS menu in Visual Studio, which launches the solution in its currently configured state/start-up project, and then launches the ANTS Memory Profiler to help.  It prepopulates all of the fields with the current project information, and all I have to do is select the ‘Start Profiling’ option. When the window comes up, it is actually quite barren, just giving ideas on how to work the profiler.  You start by getting to the point in your application that you want to profile, and then taking a ‘Memory Snapshot’.  This performs a full garbage collection, and snapshots the managed heap.  Using the same WPF app as before, I will go ahead and take a snapshot now. As you can see, ANTS is already giving me lots of information regarding the snapshot, however this is just a snapshot.  The whole point of the profiler is to perform an action, usually one where a memory problem is being noticed, and then take another snapshot and perform a diff between them to see what has changed.  I am going to go ahead and generate 5000 primes, and then take another snapshot: As you can see, ANTS is already giving me a lot of new information about this snapshot compared to the last.  Information such as difference in memory usage, fragmentation, class usage, etc…  If you take more snapshots, you can use the dropdown at the top to set your actual comparison snapshots. If you beneath the timeline, you will see a breadcrumb trail showing how best to approach profiling memory using ANTS.  When you first do the comparison, you start on the Summary screen.  You can either use the charts at the bottom, or switch to the class list screen to get to the next step.  Here is the class list screen: As you can see, it lists information about all of the instances between the snapshots, as well as at the bottom giving you a way to filter by telling ANTS what your problem is.  I am going to go ahead and select the Int16[] to look at the Instance Categorizer Using the instance categorizer, you can travel backwards to see where all of the instances are coming from.  It may be hard to see in this image, but hopefully the lightbox (click on it) will help: I can see that all of these instances are rooted to the application through the UI TextBlock control.  This image will probably be even harder to see, however using the ‘Instance Retention Graph’, you can trace an objects memory inheritance up the chain to see its roots as well.  This is a simple example, as this is simply a known element.  Usually you would be profiling an actual problem, and comparing those differences.  I know in the past, I have spotted a problem where a new context was created per page load, and it was rooted into the application through an event.  As the application began to grow, performance and reliability problems started to emerge.  A tool like this would have been a great way to identify the problem quickly. Overview Overall, I think that the Red Gate ANTS Memory Profiler is a great utility for debugging those pesky leaks.  3 Biggest Pros: Easy to use interface with lots of options for configuring profiling session Intuitive and helpful interface for drilling down from summary, to instance, to root graphs ANTS provides an API for controlling the profiler. Not many options, but still helpful. 2 Biggest Cons: Inability to automatically snapshot the memory by interval Lack of complete integration with Visual Studio via an extension panel Ratings Ease of Use (9/10) – I really do believe that they have brought simplicity to the once difficult task of memory profiling.  I especially liked how it stepped you further into the drilldown by directing you towards the best options. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Features (7/10) – A really great set of features all around in the application, however, I would like to see some ability for automatically triggering snapshots based on intervals or framework level items such as events. Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (9/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (9/10) – Overall, I am happy with the Memory Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  Thank you for reading up to here, or skipping ahead – I told you it would be shorter!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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• Big data: An evening in the life of an actual buyer

  - by Jean-Pierre Dijcks

  Here I am, and this is an actual story of one of my evenings, trying to spend money with a company and ultimately failing. I just gave up and bought a service from another vendor, not the incumbent. Here is that story and how I think big data could actually fix this (and potentially prevent some of this from happening). In the end this story should illustrate how big data can benefit me (get me what I want without causing grief) and the company I am trying to buy something from. Note: Lots of details left out, I have no intention of being the annoyed blogger moaning about a specific company. What did I want to get? We watch TV, we have internet and we do have a land line. The land line is from a different vendor then the TV and the internet. I have decided that this makes no sense and I was going to get a bundle (no need to infer who this is, I just picked the generic bundle word as this is what I want to get) of all three services as this seems to save me money. I also want to not talk to people, I just want to click on a website when I feel like it and get it all sorted. I do think that is reality. I want to just do my shopping at 9.30pm while watching silly reruns on TV. Problem 1 - Bad links So, I'm an existing customer of the company I want to buy my bundle from. I go to the website, I click on offers. Turns out they are offers for new customers. After grumbling about how good they are, I click on offers for existing customers. Bummer, it goes to offers for new customers, so I click again on the link for offers for existing customers. No cigar... it just does not work. Big data solutions: 1) Do not show an existing customer the offers for new customers unless they are the same => This is only partially doable without login, but if a customer logs in the application should always know that this is an existing customer. But in general, imagine I do this from my home going through the internet service of this vendor to their domain... an instant filter should move me into the "existing customer route". 2) Flag dead or incorrect links => I've clicked the link for "existing customer offers" at least 3 times in under 5 seconds... Identifying patterns like this is easy in Hadoop and can very quickly make a list of potentially incorrect links. No need for realtime fixing, just the fact that this link can be pro-actively fixed across my entire web domain is a good thing. Preventative maintenance! Problem 2 - Purchase cannot be completed Apart from the fact that the browsing pattern to actually get to what I want is poorly designed, my purchase never gets past a specific point. In other words, I put something into my shopping cart and when I want to move on the application either crashes (with me going to an error page) or hangs or goes into something like chat. So I try again, and again and again. I think I tried this entire path (while being logged in!!) at least 10 times over the course of 20 minutes. I also clicked on the feedback button and, frustrated as I was, tried to explain this did not work... Big Data Solutions: 1) This web site does shopping cart analysis. I got an email next day stating I have things in my shopping cart, just click here to complete my purchase. After the above experience, this just added insult to my pain... 2) What should have happened, is a Hadoop job going over all logged in customers that are on the buy flow. It should flag anyone who is trying (multiple attempts from the same user to do the same thing), analyze the shopping card, the clicks to identify what the customers wants, his feedback provided (note: always own your own website feedback, never just farm this out!!) and in a short turn around time (30 minutes to 2 hours or so) email me with a link to complete my purchase. Not with a link to my shopping cart 12 hours later, but a link to actually achieve what I wanted... Why should this company go through the big data effort? I do believe this is relatively easy to do using our Oracle Event Processing and Big Data Appliance solutions combined. It is almost so simple (to my mind) that it makes no sense that this is not in place? But, now I am ranting... Why is this interesting? It is because of $$$$. After trying really hard, I mean I did this all in the evening, and again in the morning before going to work. I kept on failing, But I really wanted this to work... so an email that said, sorry, we noticed you tried to get a bundle (the log knows what I wanted, where I failed, so easy to generate), here is the link to click and complete your purchase. And here is 2 movies on us as an apology would have kept me as a customer, and got the additional $$$$ per month for the next couple of years. It would also lead to upsell on my phone package etc. Instead, I went to a completely different company, bought service from them. Lost money for company A, negative sentiment for company A and me telling this story at the water cooler so I'm influencing more people to think negatively about company A. All in all, a loss of easy money, a ding in sentiment and image where a relatively simple solution exists and can be in place on the software I describe routinely in this blog... For those who are coming to Openworld and maybe see value in solving the above, or are thinking of how to solve this, come visit us in Moscone North - Oracle Red Lounge or in the Engineered Systems Showcase.

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• Making Those PanelBoxes Behave

  - by Duncan Mills

  I have a little problem to solve earlier this week - misbehaving <af:panelBox> components... What do I mean by that? Well here's the scenario, I have a page fragment containing a set of panelBoxes arranged vertically. As it happens, they are stamped out in a loop but that does not really matter. What I want to be able to do is to provide the user with a simple UI to close and open all of the panelBoxes in concert. This could also apply to showDetailHeader and similar items with a disclosed attrubute, but in this case it's good old panelBoxes.  Ok, so the basic solution to this should be self evident. I can set up a suitable scoped managed bean that the panelBoxes all refer to for their disclosed attribute state. Then the open all / close commandButtons in the UI can simply set the state of that bean for all the panelBoxes to pick up via EL on their disclosed attribute. Sound OK? Well that works basically without a hitch, but turns out that there is a slight problem and this is where the framework is attempting to be a little too helpful. The issue is that is the user manually discloses or hides a panelBox then that will override the value that the EL is setting. So for example. I start the page with all panelBoxes collapsed, all set by the EL state I'm storing on the session I manually disclose panelBox no 1. I press the Expand All button - all works as you would hope and all the panelBoxes are now disclosed, including of course panelBox 1 which I just expanded manually. Finally I press the Collapse All button and everything collapses except that first panelBox that I manually disclosed.  The problem is that the component remembers this manual disclosure and that overrides the value provided by the expression. If I change the viewId (navigate away and back) then the panelBox will start to behave again, until of course I touch it again! Now, the more astute amoungst you would think (as I did) Ah, sound like the MDS personalizaton stuff is getting in the way and the solution should simply be to set the dontPersist attribute to disclosed | ALL. Alas this does not fix the issue.  After a little noodling on the best way to approach this I came up with a solution that works well, although if you think of an alternative way do let me know. The principle is simple. In the disclosureListener for the panelBox I take a note of the clientID of the panelBox component that has been touched by the user along with the state. This all gets stored in a Map of Booleans in ViewScope which is keyed by clientID and stores the current disclosed state in the Boolean value.  The listener looks like this (it's held in a request scope backing bean for the page): public void handlePBDisclosureEvent(DisclosureEvent disclosureEvent) { String clientId = disclosureEvent.getComponent().getClientId(FacesContext.getCurrentInstance()); boolean state = disclosureEvent.isExpanded(); pbState.addTouchedPanelBox(clientId, state); } The pbState variable referenced here is a reference to the bean which will hold the state of the panelBoxes that lives in viewScope (recall that everything is re-set when the viewid is changed so keeping this in viewScope is just fine and cleans things up automatically). The addTouchedPanelBox() method looks like this: public void addTouchedPanelBox(String clientId, boolean state) { //create the cache if needed this is just a Map<String,Boolean> if (_touchedPanelBoxState == null) { _touchedPanelBoxState = new HashMap<String, Boolean>(); } // Simply put / replace _touchedPanelBoxState.put(clientId, state); } So that's the first part, we now have a record of every panelBox that the user has touched. So what do we do when the Collapse All or Expand All buttons are pressed? Here we do some JavaScript magic. Basically for each clientID that we have stored away, we issue a client side disclosure event from JavaScript - just as if the user had gone back and changed it manually. So here's the Collapse All button action: public String CloseAllAction() { submitDiscloseOverride(pbState.getTouchedClientIds(true), false); _uiManager.closeAllBoxes(); return null; }  The _uiManager.closeAllBoxes() method is just manipulating the master-state that all of the panelBoxes are bound to using EL. The interesting bit though is the line:  submitDiscloseOverride(pbState.getTouchedClientIds(true), false); To break that down, the first part is a call to that viewScoped state holder to ask for a list of clientIDs that need to be "tweaked": public String getTouchedClientIds(boolean targetState) { StringBuilder sb = new StringBuilder(); if (_touchedPanelBoxState != null && _touchedPanelBoxState.size() > 0) { for (Map.Entry<String, Boolean> entry : _touchedPanelBoxState.entrySet()) { if (entry.getValue() == targetState) { if (sb.length() > 0) { sb.append(','); } sb.append(entry.getKey()); } } } return sb.toString(); } You'll notice that this method only processes those panelBoxes that will be in the wrong state and returns those as a comma separated list. This is then processed by the submitDiscloseOverride() method: private void submitDiscloseOverride(String clientIdList, boolean targetDisclosureState) { if (clientIdList != null && clientIdList.length() > 0) { FacesContext fctx = FacesContext.getCurrentInstance(); StringBuilder script = new StringBuilder(); script.append("overrideDiscloseHandler('"); script.append(clientIdList); script.append("',"); script.append(targetDisclosureState); script.append(");"); Service.getRenderKitService(fctx, ExtendedRenderKitService.class).addScript(fctx, script.toString()); } } This method constructs a JavaScript command to call a routine called overrideDiscloseHandler() in a script attached to the page (using the standard <af:resource> tag). That method parses out the list of clientIDs and sends the correct message to each one: function overrideDiscloseHandler(clientIdList, newState) { AdfLogger.LOGGER.logMessage(AdfLogger.INFO, "Disclosure Hander newState " + newState + " Called with: " + clientIdList); //Parse out the list of clientIds var clientIdArray = clientIdList.split(','); for (var i = 0; i < clientIdArray.length; i++){ var panelBox = flipPanel = AdfPage.PAGE.findComponentByAbsoluteId(clientIdArray[i]); if (panelBox.getComponentType() == "oracle.adf.RichPanelBox"){ panelBox.broadcast(new AdfDisclosureEvent(panelBox, newState)); } }  }  So there you go. You can see how, with a few tweaks the same code could be used for other components with disclosure that might suffer from the same problem, although I'd point out that the behavior I'm working around here us usually desirable. You can download the running example (11.1.2.2) from here. 

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• Azure Task Scheduling Options

  - by charlie.mott

  Currently, the Azure PaaS does not offer a distributed\resilient task scheduling service.  If you do want to host a task scheduling product\solution off-premise (and ideally use Azure), what are your options? PaaS Option 1: Worker Roles Use a worker role to schedule and execute actions at specific time periods.  There are a few frameworks available to assist with this: http://azuretoolkit.codeplex.com https://github.com/Lokad/lokad-cloud/wiki/TaskScheduler http://blog.smarx.com/posts/building-a-task-scheduler-in-windows-azure - This addresses a slightly different set of requirements. It’s a more dynamic approach for queuing up tasks, but not repeatable tasks (e.g. daily). I found the Azure Toolkit option the most simple to implement.  Step 1 : Create a domain entity implementing IJob for each job to schedule.  In this sample, I asynchronously call a WCF service method. 1: namespace Acme.WorkerRole.Jobs 2: { 3: using AzureToolkit; 4: using ScheduledTasksService; 5: 6: public class UploadEmployeesJob : IJob 7: { 8: public void Run() 9: { 10: // Call Tasks Service 11: var client = new ScheduledTasksServiceClient("BasicHttpBinding_IScheduledTasksService"); 12: client.UploadEmployees(); 13: client.Close(); 14: } 15: } 16: } Step 2 : In the worker role run method, add the jobs to the toolkit engine. 1: namespace Acme.WorkerRole 2: { 3: using AzureToolkit.Engine; 4: using Jobs; 5:   6: public class WorkerRole : WorkerRoleEntryPoint 7: { 8: public override void Run() 9: { 10: var engine = new CloudEngine(); 11:   12: // Add Scheduled Jobs (using CronJob syntax - see http://www.adminschoice.com/crontab-quick-reference). 13:   14: // 1. Upload Employee job - 8.00 PM every weekday (Mon-Fri) 15: engine.WithJobScheduler().ScheduleJob<UploadEmployeesJob>(c => { c.CronSchedule = "0 20 * * 1-5"; }); 16: // 2. Purge Data job - 10 AM every Saturday 17: engine.WithJobScheduler().ScheduleJob<PurgeDataJob>(c => { c.CronSchedule = "0 10 * * 6"; }); 18: // 3. Process Exceptions job - Every 5 minutes 19: engine.WithJobScheduler().ScheduleJob<ProcessExceptionsJob>(c => { c.CronSchedule = "*/5 * * * *"; }); 20:   21: engine.Run(); 22: base.Run(); 23: } 24: } 25: } Pros Cons Azure Toolkit option is simple to implement. For the AzureToolkit option, you are limited to a single worker role.  Otherwise, the jobs will be executed multiple times, once for each worker role instance.   Paying for a continuously running worker role, even if it just processes a single job once a week.  If you only have a few scheduled tasks to run calling asynchronous services hosted in different web roles, an extra small worker role likely to be sufficient.  However, for an extra small worker role this still costs $14.40/month (03/09/2012). Option 2: Use Scheduled Task on Azure Web Role calling a console app Setup a Windows Scheduled Task on the Azure Web Role. This calls a console application that calls the WCF service methods that run the task actions. This design is described here: http://www.ronaldwidha.net/2011/02/23/cron-job-on-azure-using-scheduled-task-on-a-web-role-to-replace-azure-worker-role-for-background-job/ http://www.voiceoftech.com/swhitley/index.php/2011/07/windows-azure-task-scheduler/ http://devlicio.us/blogs/vinull/archive/2011/10/23/moving-to-azure-worker-roles-for-nothing-and-tasks-for-free.aspx Pros Cons Fairly easy to implement. Supportability - I RDC’ed onto the Azure server and stopped the scheduled task. I then rebooted the machine and the task was re-started. I also tried deleting the task and rebooting, the same thing occurred. The only way to permanently guarantee that a task is disabled is to do a fresh deployment. I think this is a major supportability concern.   Saleability - multiple instances would trigger multiple tasks. You can only have one instance for the scheduled task web role. The guidance implements setup of the scheduled task as part of a web role instance. But if you have more than one instance in a web role, the task will be triggered multiple times for each scheduled action (once per machine). Workaround: If we wanted to use scheduled tasks for another client with a saleable WCF service, then we could include the console & tasks scripts in a separate web role (e.g. a empty WCF service with no real purpose to it). SaaS Option 3: Azure Marketplace I thought that someone might be offering this type of service via the Azure marketplace. At the point of writing this blog post, I did not find anyone doing so. https://datamarket.azure.com/ Pros Cons   Nobody currently offers this on the Azure Marketplace. Option 4: Online Job Scheduling Service Provider There are plenty of online providers that offer this type of service on a pay-as-you-go approach.  Some of these are free for small usage.   Many of these providers are listed here: http://en.wikipedia.org/wiki/Webcron Pros Cons No bespoke development for scheduler. Reliance on third party. IaaS Option 5: Setup Scheduling Software on Azure IaaS VM’s One of job scheduling software offerings could be installed and configured on Azure VM’s.  A list of software options is listed here: http://en.wikipedia.org/wiki/List_of_job_scheduler_software Pros Cons Enterprise distributed\resilient task scheduling service VM Setup and maintenance   Software Licence Costs Option 6: VM Gallery A the time of writing this blog post, I did not spot a VM in the gallery that included pre-installation of any of the above software options. Pros Cons   No current VM template. Summary For my current project that had a small handful of tasks to schedule with a limited project budget I chose option 1 (a worker role using the Azure Toolkit to schedule tasks).  If I was building an enterprise scale solution for the future, options 4 and 5 are currently worthy of consideration. Hopefully, Microsoft will include tasks scheduling in the future as part of their PaaS offerings.

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• Adventures in Windows 8: Working around the navigation animation issues in LayoutAwarePage

  - by Laurent Bugnion

  LayoutAwarePage is a pretty cool add-on to Windows 8 apps, which facilitates greatly the implementation of orientation-aware (portrait, landscape) as well as state-aware (snapped, filled, fullscreen) apps. It has however a few issues that are obvious when you use transformed elements on your page. Adding a LayoutAwarePage to your application If you start with a blank app, the MainPage is a vanilla Page, with no such feature. In order to have a LayoutAwarePage into your app, you need to add this class (and a few helpers) with the following operation: Right click on the Solution and select Add, New Item from the context menu. From the dialog, select a Basic Page (not a Blank Page, which is another vanilla page). If you prefer, you can also use Split Page, Items Page, Item Detail Page, Grouped Items Page or Group Detail Page which are all LayoutAwarePages. Personally I like to start with a Basic Page, which gives me more creative freedom. Adding this new page will cause Visual Studio to show a prompt asking you for permission to add additional helper files to the Common folder. One of these helpers in the LayoutAwarePage class, which is where the magic happens. LayoutAwarePage offers some help for the detection of orientation and state (which makes it a pleasure to design for all these scenarios in Blend, by the way) as well as storage for the navigation state (more about that in a future article). Issue with LayoutAwarePage When you use UI elements such as a background picture, a watermark label, logos, etc, it is quite common to do a few things with those: Making them partially transparent (this is especially true for background pictures; for instance I really like a black Page background with a half transparent picture placed on top of it). Transforming them, for instance rotating them a bit, scaling them, etc. Here is an example with a picture of my two beautiful daughters in the Bird Park in Kuala Lumpur, as well as a transformed TextBlock. The image has an opacity of 40% and the TextBlock a simple RotateTransform. If I create an application with a MainPage that navigates to this LayoutAwarePage, however, I will have a very annoying effect: The background picture appears with an Opacity of 100%. The TextBlock is not rotated. This lasts only for less than a second (during the navigation animation) before the elements “snap into place” and get their desired effect. Here is the XAML that cause the annoying effect: <common:LayoutAwarePage x:Name="pageRoot" x:Class="App13.BasicPage1" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:common="using:App13.Common" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d"> <Grid Style="{StaticResource LayoutRootStyle}"> <Grid.RowDefinitions> <RowDefinition Height="140" /> <RowDefinition Height="*" /> </Grid.RowDefinitions> <Image Source="Assets/el20120812025.jpg" Stretch="UniformToFill" Opacity="0.4" Grid.RowSpan="2" /> <Grid> <Grid.ColumnDefinitions> <ColumnDefinition Width="Auto" /> <ColumnDefinition Width="*" /> </Grid.ColumnDefinitions> <Button x:Name="backButton" Click="GoBack" IsEnabled="{Binding Frame.CanGoBack, ElementName=pageRoot}" Style="{StaticResource BackButtonStyle}" /> <TextBlock x:Name="pageTitle" Grid.Column="1" Text="Welcome" Style="{StaticResource PageHeaderTextStyle}" /> </Grid> <TextBlock HorizontalAlignment="Center" TextWrapping="Wrap" Text="Welcome to my Windows 8 Application" Grid.Row="1" VerticalAlignment="Bottom" FontFamily="Segoe UI Light" FontSize="70" FontWeight="Light" TextAlignment="Center" Foreground="#FFFFA200" RenderTransformOrigin="0.5,0.5" UseLayoutRounding="False" d:LayoutRounding="Auto" Margin="0,0,0,153"> <TextBlock.RenderTransform> <CompositeTransform Rotation="-6.545" /> </TextBlock.RenderTransform> </TextBlock> <VisualStateManager.VisualStateGroups> [...] </VisualStateManager.VisualStateGroups> </Grid> </common:LayoutAwarePage> Solving the issue In order to solve this “snapping” issue, the solution is to wrap the elements that are transformed into an empty Grid. Honestly, to me it sounds like a bug in the LayoutAwarePage navigation animation, but thankfully the workaround is not that difficult: Simple change the main Grid as follows: <Grid Style="{StaticResource LayoutRootStyle}"> <Grid.RowDefinitions> <RowDefinition Height="140" /> <RowDefinition Height="*" /> </Grid.RowDefinitions> <Grid Grid.RowSpan="2"> <Image Source="Assets/el20120812025.jpg" Stretch="UniformToFill" Opacity="0.4" /> </Grid> <Grid> <Grid.ColumnDefinitions> <ColumnDefinition Width="Auto" /> <ColumnDefinition Width="*" /> </Grid.ColumnDefinitions> <Button x:Name="backButton" Click="GoBack" IsEnabled="{Binding Frame.CanGoBack, ElementName=pageRoot}" Style="{StaticResource BackButtonStyle}" /> <TextBlock x:Name="pageTitle" Grid.Column="1" Text="Welcome" Style="{StaticResource PageHeaderTextStyle}" /> </Grid> <Grid Grid.Row="1"> <TextBlock HorizontalAlignment="Center" TextWrapping="Wrap" Text="Welcome to my Windows 8 Application" VerticalAlignment="Bottom" FontFamily="Segoe UI Light" FontSize="70" FontWeight="Light" TextAlignment="Center" Foreground="#FFFFA200" RenderTransformOrigin="0.5,0.5" UseLayoutRounding="False" d:LayoutRounding="Auto" Margin="0,0,0,153"> <TextBlock.RenderTransform> <CompositeTransform Rotation="-6.545" /> </TextBlock.RenderTransform> </TextBlock> </Grid> <VisualStateManager.VisualStateGroups> [...] </Grid> Hopefully this will help a few people, I banged my head on the wall for a while before someone at Microsoft pointed me to the solution ;) Happy coding, Laurent   Laurent Bugnion (GalaSoft) Subscribe | Twitter | Facebook | Flickr | LinkedIn

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• Who could ask for more with LESS CSS? (Part 2 of 3&ndash;Setup)

  - by ToStringTheory

  Welcome to part two in my series covering the LESS CSS language.  In the first post, I covered the two major CSS precompiled languages - LESS and SASS to a small extent, iterating over some of the features that you could expect to find in them.  In this post, I will go a little further in depth into the setup and execution of using the LESS framework. Introduction It really doesn’t take too much to get LESS working in your project.  The basic workflow will be including the necessary translator in your project, defining bundles for the LESS files, add the necessary code to your layouts.cshtml file, and finally add in all your necessary styles to the LESS files!  Lets get started… New Project Just like all great experiments in Visual Studio, start up a File > New Project, and create a new MVC 4 Web Application.  The Base Package After you have the new project spun up, use the Nuget Package Manager to install the Bundle Transformer: LESS package. This will take care of installing the main translator that we will be using for LESS code (dotless which is another Nuget package), as well as the core framework for the Bundle Transformer library.  The installation will come up with some instructions in a readme file on how to modify your web.config to handle all your *.less requests through the Bundle Transformer, which passes the translating onto dotless. Where To Put These LESS Files?! This step isn’t really a requirement, however I find that I don’t like how ASP.Net MVC just has a content directory where they store CSS, content images, css images….  In my project, I went ahead and created a new directory just for styles – LESS files, CSS files, and images that are only referenced in LESS or CSS.  Ignore the MVC directory as this was my testbed for another project I was working on at the same time.  As you can see here, I have: A top level directory for images which contains only images used in a page A top level directory for scripts A top level directory for Styles A few directories for plugins I am using (Colrizr, JQueryUI, Farbtastic) Multiple *.less files for different functions (I’ll go over these in a minute) I find that this layout offers the best separation of content types.  Bring Out Your Bundles! The next thing that we need to do is add in the necessary code for the bundling of these LESS files.  Go ahead and open your BundleConfig.cs file, usually located in the /App_Start/ folder of the project.  As you will see in a minute, instead of using the method Microsoft does in the base MVC 4 project, I change things up a bit.  Define Constants The first thing I do is define constants for each of the virtual paths that will be used in the bundler: The main reason is that I hate magic strings in my program, so the fact that you first defined a virtual path in the BundleConfig file, and then used that path in the _Layout.cshtml file really irked me. Add Bundles to the BundleCollection Next, I am going to define the bundles for my styles in my AddStyleBundles method: That is all it takes to get all of my styles in play with LESS.  The CssTransformer and NullOrderer types come from the Bundle Transformer we grabbed earlier.  If we didn’t use that package, we would have to write our own function (not too hard, but why do it if it’s been done). I use the site.less file as my main hub for LESS - I will cover that more in the next section. Add Bundles To Layout.cshtml File With the constants in the BundleConfig file, instead of having to use the same magic string I defined for the bundle virtual path, I am able to do this: Notice here that besides the RenderSection magic strings (something I am working on in another side project), all of the bundles are now based on const strings.  If I need to change the virtual path, I only have to do it in one place.  Nifty! Get Started! We are now ready to roll!  As I said in the previous section, I use the site.less file as a central hub for my styles: As seen here, I have a reset.css file which is a simple CSS reset.  Next, I have created a file for managing all my color variables – colors.less: Here, you can see some of the standards I started to use, in this case for color variables.  I define all color variables with the @col prefix.  Currently, I am going for verbose variable names. The next file imported is my font.less file that defines the typeface information for the site: Simple enough.  A couple of imports for fonts from Google, and then declaring variables for use throughout LESS.  I also set up the heading sizes, margins, etc..  You can also see my current standardization for font declaration strings – @font. Next, I pull in a mixins.less file that I grabbed from the Twitter Bootstrap library that gives some useful parameterized mixins for use such as border-radius, gradient, box-shadow, etc… The common.less file is a file that just contains items that I will be defining that can be used across all my LESS files.  Kind of like my own mixins or font-helpers: Finally I have my layout.less file that contains all of my definitions for general site layout – width, main/sidebar widths, footer layout, etc: That’s it!  For the rest of my one off definitions/corrections, I am currently putting them into the site.less file beneath my original imports Note Probably my favorite side effect of using the LESS handler/translator while bundling is that it also does a CSS checkup when rendering…  See, when your web.config is set to debug, bundling will output the url to the direct less file, not the bundle, and the http handler intercepts the call, compiles the less, and returns the result.  If there is an error in your LESS code, the CSS file can be returned empty, or may have the error output as a comment on the first couple lines. If you have the web.config set to not debug, then if there is an error in your code, you will end up with the usual ASP.Net exception page (unless you catch the exception of course), with information regarding the failure of the conversion, such as brace mismatch, undefined variable, etc…  I find it nifty. Conclusion This is really just the beginning.  LESS is very powerful and exciting!  My next post will show an actual working example of why LESS is so powerful with its functions and variables…  At least I hope it will!  As for now, if you have any questions, comments, or suggestions on my current practice, I would love to hear them!  Feel free to drop a comment or shoot me an email using the contact page.  In the mean time, I plan on posting the final post in this series tomorrow or the day after, with my side project, as well as a whole base ASP.Net MVC4 templated project with LESS added in it so that you can check out the layout I have in this post.  Until next time…

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