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• Clustering Basics and Challenges

  - by Karoly Vegh

  For upcoming posts it seemed to be a good idea to dedicate some time for cluster basic concepts and theory. This post misses a lot of details that would explode the articlesize, should you have questions, do not hesitate to ask them in the comments.  The goal here is to get some concepts straight. I can't promise to give you an overall complete definitions of cluster, cluster agent, quorum, voting, fencing, split brain condition, so the following is more of an explanation. Here we go. -------- Cluster, HA, failover, switchover, scalability -------- An attempted definition of a Cluster: A cluster is a set (2+) server nodes dedicated to keep application services alive, communicating through the cluster software/framework with eachother, test and probe health status of servernodes/services and with quorum based decisions and with switchover/failover techniques keep the application services running on them available. That is, should a node that runs a service unexpectedly lose functionality/connection, the other ones would take over the and run the services, so that availability is guaranteed. To provide availability while strictly sticking to a consistent clusterconfiguration is the main goal of a cluster.  At this point we have to add that this defines a HA-cluster, a High-Availability cluster, where the clusternodes are planned to run the services in an active-standby, or failover fashion. An example could be a single instance database. Some applications can be run in a distributed or scalable fashion. In the latter case instances of the application run actively on separate clusternodes serving servicerequests simultaneously. An example for this version could be a webserver that forwards connection requests to many backend servers in a round-robin way. Or a database running in active-active RAC setup.  -------- Cluster arhitecture, interconnect, topologies -------- Now, what is a cluster made of? Servers, right. These servers (the clusternodes) need to communicate. This of course happens over the network, usually over dedicated network interfaces interconnecting all the clusternodes. These connection are called interconnects.How many clusternodes are in a cluster? There are different cluster topologies. The most simple one is a clustered pair topology, involving only two clusternodes:  There are several more topologies, clicking the image above will take you to the relevant documentation. Also, to answer the question Solaris Cluster allows you to run up to 16 servers in a cluster. Where shall these clusternodes be placed? A very important question. The right answer is: It depends on what you plan to achieve with the cluster. Do you plan to avoid only a server outage? Then you can place them right next to eachother in the datacenter. Do you need to avoid DataCenter outage? In that case of course you should place them at least in different fire zones. Or in two geographically distant DataCenters to avoid disasters like floods, large-scale fires or power outages. We call this a stretched- or campus cluster, the clusternodes being several kilometers away from eachother. To cover really large distances, you probably need to move to a GeoCluster, which is a different kind of animal.  What is a geocluster? A Geographic Cluster in Solaris Cluster terms is actually a metacluster between two, separate (locally-HA) clusters.  -------- Cluster resource types, agents, resources, resource groups -------- So how does the cluster manage my applications? The cluster needs to start, stop and probe your applications. If you application runs, the cluster needs to check regularly if the application state is healthy, does it respond over the network, does it have all the processes running, etc. This is called probing. If the cluster deems the application is in a faulty state, then it can try to restart it locally or decide to switch (stop on node A, start on node B) the service. Starting, stopping and probing are the three actions that a cluster agent does. There are many different kinds of agents included in Solaris Cluster, but you can build your own too. Examples are an agent that manages (mounts, moves) ZFS filesystems, or the Oracle DB HA agent that cares about the database, or an agent that moves a floating IP address between nodes. There are lots of other agents included for Apache, Tomcat, MySQL, Oracle DB, Oracle Weblogic, Zones, LDoms, NFS, DNS, etc.We also need to clarify the difference between a cluster resource and the cluster resource group.A cluster resource is something that is managed by a cluster agent. Cluster resource types are included in Solaris cluster (see above, e.g. HAStoragePlus, HA-Oracle, LogicalHost). You can group cluster resources into cluster resourcegroups, and switch these groups together from one node to another. To stick to the example above, to move an Oracle DB service from one node to another, you have to switch the group between nodes, and the agents of the cluster resources in the group will do the following:  On node A Shut down the DB Unconfigure the LogicalHost IP the DB Listener listens on unmount the filesystem   Then, on node B: mount the FS configure the IP  startup the DB -------- Voting, Quorum, Split Brain Condition, Fencing, Amnesia -------- How do the clusternodes agree upon their action? How do they decide which node runs what services? Another important question. Running a cluster is a strictly democratic thing.Every node has votes, and you need the majority of votes to have the deciding power. Now, this is usually no problem, clusternodes think very much all alike. Still, every action needs to be governed upon in a productive system, and has to be agreed upon. Agreeing is easy as long as the clusternodes all behave and talk to eachother over the interconnect. But if the interconnect is gone/down, this all gets tricky and confusing. Clusternodes think like this: "My job is to run these services. The other node does not answer my interconnect communication, it must be down. I'd better take control and run the services!". The problem is, as I have already mentioned, clusternodes very much think alike. If the interconnect is gone, they all assume the other node is down, and they all want to mount the data backend, enable the IP and run the database. Double IPs, double mounts, double DB instances - now that is trouble. Also, in a 2-node cluster they both have only 50% of the votes, that is, they themselves alone are not allowed to run a cluster.  This is where you need a quorum device. According to Wikipedia, the "requirement for a quorum is protection against totally unrepresentative action in the name of the body by an unduly small number of persons.". They need additional votes to run the cluster. For this requirement a 2-node cluster needs a quorum device or a quorum server. If the interconnect is gone, (this is what we call a split brain condition) both nodes start to race and try to reserve the quorum device to themselves. They do this, because the quorum device bears an additional vote, that could ensure majority (50% +1). The one that manages to lock the quorum device (e.g. if it's an FC LUN, it SCSI reserves it) wins the right to build/run a cluster, the other one - realizing he was late - panics/reboots to ensure the cluster config stays consistent.  Losing the interconnect isn't only endangering the availability of services, but it also endangers the cluster configuration consistence. Just imagine node A being down and during that the cluster configuration changes. Now node B goes down, and node A comes up. It isn't uptodate about the cluster configuration's changes so it will refuse to start a cluster, since that would lead to cluster amnesia, that is the cluster had some changes, but now runs with an older cluster configuration repository state, that is it's like it forgot about the changes.  Also, to ensure application data consistence, the clusternode that wins the race makes sure that a server that isn't part of or can't currently join the cluster can access the devices. This procedure is called fencing. This usually happens to storage LUNs via SCSI reservation.  Now, another important question: Where do I place the quorum disk?  Imagine having two sites, two separate datacenters, one in the north of the city and the other one in the south part of it. You run a stretched cluster in the clustered pair topology. Where do you place the quorum disk/server? If you put it into the north DC, and that gets hit by a meteor, you lose one clusternode, which isn't a problem, but you also lose your quorum, and the south clusternode can't keep the cluster running lacking the votes. This problem can't be solved with two sites and a campus cluster. You will need a third site to either place the quorum server to, or a third clusternode. Otherwise, lacking majority, if you lose the site that had your quorum, you lose the cluster. Okay, we covered the very basics. We haven't talked about virtualization support, CCR, ClusterFilesystems, DID devices, affinities, storage-replication, management tools, upgrade procedures - should those be interesting for you, let me know in the comments, along with any other questions. Given enough demand I'd be glad to write a followup post too. Now I really want to move on to the second part in the series: ClusterInstallation.  Oh, as for additional source of information, I recommend the documentation: http://docs.oracle.com/cd/E23623_01/index.html, and the OTN Oracle Solaris Cluster site: http://www.oracle.com/technetwork/server-storage/solaris-cluster/index.html

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• Choice of open source license for some components, closed source for others

  - by Peter Serwylo

  G'day, I am working on a set of multiplayer games, where different games play against each other (e.g. you play a Tetris clone, I play an Asteroids clone, but we are both competing against each other). All the games would be based on the same underlying framework written specifically for this project. I am struggling to comprehend how I would license this so that: The underlying framework is open source, so other people can create new games based on it. Some games built on the framework are open source Other games are closed source The goal is to have two bundles on something like the Android market: One free and open source package which has a collection of games Another "premium" (although I dislike that word) paid package which has a different collection of games. Usually I am fond of permissive licenses such as MIT/BSD, however I would prefer something more in the vein of the GPL for this. This is because for software such as the snes-9x SNES emulator, which is a great piece of software, there is a ton of poor quality versions being sold, whereas it would be preferable if there was just one authoritative version which was always kept up to date, and distributed for free. If the underlying framework was GPL'd, would I be able to build closed source games on top of it? Thanks for your input.

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• SQL SERVER – 2012 – Summary of All the Analytic Functions – MSDN and SQLAuthority

  - by pinaldave

  SQL Server 2012 (RC0 Available here) has introduced new analytic functions. These functions were long awaited and I am glad that they are here. Previously when any of this function was needed people use to write long T-SQL code to simulate that and now no need of the same. Having available native function also helps performance as well readability. In last few days I have written many articles on this subject on my blog. The goal was make these complex analytic functions easy to understand and make it widely accepted. As this new functions are available and as awareness spreads we should start using the new functions. Here is the quick list of the new function and relevant MSDN site. Function SQLAuthority MSDN CUME_DIST CUME_DIST CUME_DIST FIRST_VALUE FIRST_VALUE FIRST_VALUE LAST_VALUE LAST_VALUE LAST_VALUE LEAD LEAD LEAD LAG LAG LAG PERCENTILE_CONT PERCENTILE_CONT PERCENTILE_CONT PERCENTILE_DISC PERCENTILE_DISC PERCENTILE_DISC PERCENT_RANK PERCENT_RANK PERCENT_RANK I also enjoyed three different puzzles during the course of this series which gave clear idea to the SQL Server 2012 analytic functions. SQL SERVER – Puzzle to Win Print Book – Functions FIRST_VALUE and LAST_VALUE with OVER clause and ORDER BY SQL SERVER – Puzzle to Win Print Book – Write T-SQL Self Join Without Using LEAD and LAG SQL SERVER – Puzzle to Win Print Book – Explain Value of PERCENTILE_CONT() Using Simple Example This series will be always my dear series as during this series I had went through very unique experience of my book going out of stock and becoming available after 48 hours. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Function, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Disaster Recovery Plan&ndash;Rebuild System Disk (Dell Server 2900 with PERC RAID controller)

  - by Jim Lahman

  Goal: Since the system disk is a RAID 1 mirrored set, we can rebuild the shadow set by replacing one of the good sets with a blank disk Steps Shutdown and power down server Remove the disk from bay 9, which is part of the system shadow set. Put this disk on the shelf Insert blank/old disk into the empty bay     Label the new disk before inserting it into the empty bay       Power up server During the booting process, the following message appears: “Some configured disks have been removed from your system…”       Press ‘C’ to Load Configuration utility             Press 'Y' to confirm to load the foreign configuration       In this example, the system shadow set is Disk Group 2.  (Before proceeding, confirm this is the disk group in your case).  Expanding the physical disks shows a disk in bay 8 and a missing disk in bay 9.  This is correct.   Now, we have to include the new inserted disk in this group       RAID controller reporting bay 9 is empty       There may be times when the new disk is seen as a foreign disk.  In this case, do the following:     Foreign disk is reported in bay 9 CTRL-N (Next Page) to Foreign Mgt All the disk groups will be displayed.  Typically, the disk group containing the foreign disk will be grey.  To remove the foreign disk Highlight Controller Press F2 Select Foreign Select Clear (do NOT import the configuration!)       Clear the foreign configuration Now the disk can be brought into the system shadow set disk group as a hot spare   To include the newly inserted disk into the system shadowset disk group, it must be brought in as a hot spare Highlight Disk Group 2 (VD Management) Hit F2 Select 'Manage Ded. HS'     Manage dedicated hot swap Select the disk in bay 9 (Hit space bar to select) Tab to 'OK'.  Hit the return key     Select hot spare to bring into RAID 1 mirror set   Rebuild automatically commences     Rebuild in process   Restart now or restart after rebuild is completed

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• T-SQL Tuesday #53-Matt's Making Me Do This!

  - by Most Valuable Yak (Rob Volk)

  Hello everyone! It's that time again, time for T-SQL Tuesday, the wonderful blog series started by Adam Machanic (b|t). This month we are hosted by Matt Velic (b|t) who asks the question, "Why So Serious?", in celebration of April Fool's Day. He asks the contributors for their dirty tricks. And for some reason that escapes me, he and Jeff Verheul (b|t) seem to think I might be able to write about those. Shocked, I am! Nah, not really. They're absolutely right, this one is gonna be fun! I took some inspiration from Matt's suggestions, namely Resource Governor and Login Triggers.  I've done some interesting login trigger stuff for a presentation, but nothing yet with Resource Governor. Best way to learn it! One of my oldest pet peeves is abuse of the sa login. Don't get me wrong, I use it too, but typically only as SQL Agent job owner. It's been a while since I've been stuck with it, but back when I started using SQL Server, EVERY application needed sa to function. It was hard-coded and couldn't be changed. (welllllll, that is if you didn't use a hex editor on the EXE file, but who would do such a thing?) My standard warning applies: don't run anything on this page in production. In fact, back up whatever server you're testing this on, including the master database. Snapshotting a VM is a good idea. Also make sure you have other sysadmin level logins on that server. So here's a standard template for a logon trigger to address those pesky sa users: CREATE TRIGGER SA_LOGIN_PRIORITY ON ALL SERVER WITH ENCRYPTION, EXECUTE AS N'sa' AFTER LOGON AS IF ORIGINAL_LOGIN()<>N'sa' OR APP_NAME() LIKE N'SQL Agent%' RETURN; -- interesting stuff goes here GO   What can you do for "interesting stuff"? Books Online limits itself to merely rolling back the logon, which will throw an error (and alert the person that the logon trigger fired).  That's a good use for logon triggers, but really not tricky enough for this blog.  Some of my suggestions are below: WAITFOR DELAY '23:59:59';   Or: EXEC sp_MSforeach_db 'EXEC sp_detach_db ''?'';'   Or: EXEC msdb.dbo.sp_add_job @job_name=N'`', @enabled=1, @start_step_id=1, @notify_level_eventlog=0, @delete_level=3; EXEC msdb.dbo.sp_add_jobserver @job_name=N'`', @server_name=@@SERVERNAME; EXEC msdb.dbo.sp_add_jobstep @job_name=N'`', @step_id=1, @step_name=N'`', @command=N'SHUTDOWN;'; EXEC msdb.dbo.sp_start_job @job_name=N'`';   Really, I don't want to spoil your own exploration, try it yourself!  The thing I really like about these is it lets me promote the idea that "sa is SLOW, sa is BUGGY, don't use sa!".  Before we get into Resource Governor, make sure to drop or disable that logon trigger. They don't work well in combination. (Had to redo all the following code when SSMS locked up) Resource Governor is a feature that lets you control how many resources a single session can consume. The main goal is to limit the damage from a runaway query. But we're not here to read about its main goal or normal usage! I'm trying to make people stop using sa BECAUSE IT'S SLOW! Here's how RG can do that: USE master; GO CREATE FUNCTION dbo.SA_LOGIN_PRIORITY() RETURNS sysname WITH SCHEMABINDING, ENCRYPTION AS BEGIN RETURN CASE WHEN ORIGINAL_LOGIN()=N'sa' AND APP_NAME() NOT LIKE N'SQL Agent%' THEN N'SA_LOGIN_PRIORITY' ELSE N'default' END END GO CREATE RESOURCE POOL SA_LOGIN_PRIORITY WITH ( MIN_CPU_PERCENT = 0 ,MAX_CPU_PERCENT = 1 ,CAP_CPU_PERCENT = 1 ,AFFINITY SCHEDULER = (0) ,MIN_MEMORY_PERCENT = 0 ,MAX_MEMORY_PERCENT = 1 -- ,MIN_IOPS_PER_VOLUME = 1 ,MAX_IOPS_PER_VOLUME = 1 -- uncomment for SQL Server 2014 ); CREATE WORKLOAD GROUP SA_LOGIN_PRIORITY WITH ( IMPORTANCE = LOW ,REQUEST_MAX_MEMORY_GRANT_PERCENT = 1 ,REQUEST_MAX_CPU_TIME_SEC = 1 ,REQUEST_MEMORY_GRANT_TIMEOUT_SEC = 1 ,MAX_DOP = 1 ,GROUP_MAX_REQUESTS = 1 ) USING SA_LOGIN_PRIORITY; ALTER RESOURCE GOVERNOR WITH (CLASSIFIER_FUNCTION=dbo.SA_LOGIN_PRIORITY); ALTER RESOURCE GOVERNOR RECONFIGURE;   From top to bottom: Create a classifier function to determine which pool the session should go to. More info on classifier functions. Create the pool and provide a generous helping of resources for the sa login. Create the workload group and further prioritize those resources for the sa login. Apply the classifier function and reconfigure RG to use it. I have to say this one is a bit sneakier than the logon trigger, least of all you don't get any error messages.  I heartily recommend testing it in Management Studio, and click around the UI a lot, there's some fun behavior there. And DEFINITELY try it on SQL 2014 with the IO settings included!  You'll notice I made allowances for SQL Agent jobs owned by sa, they'll go into the default workload group.  You can add your own overrides to the classifier function if needed. Some interesting ideas I didn't have time for but expect you to get to before me: Set up different pools/workgroups with different settings and randomize which one the classifier chooses Do the same but base it on time of day (Books Online example covers this)... Or, which workstation it connects from. This can be modified for certain special people in your office who either don't listen, or are attracted (and attractive) to you. And if things go wrong you can always use the following from another sysadmin or Dedicated Admin connection: ALTER RESOURCE GOVERNOR DISABLE;   That will let you go in and either fix (or drop) the pools, workgroups and classifier function. So now that you know these types of things are possible, and if you are tired of your team using sa when they shouldn't, I expect you'll enjoy playing with these quite a bit! Unfortunately, the aforementioned Dedicated Admin Connection kinda poops on the party here.  Books Online for both topics will tell you that the DAC will not fire either feature. So if you have a crafty user who does their research, they can still sneak in with sa and do their bidding without being hampered. Of course, you can still detect their login via various methods, like a server trace, SQL Server Audit, extended events, and enabling "Audit Successful Logins" on the server.  These all have their downsides: traces take resources, extended events and SQL Audit can't fire off actions, and enabling successful logins will bloat your error log very quickly.  SQL Audit is also limited unless you have Enterprise Edition, and Resource Governor is Enterprise-only.  And WORST OF ALL, these features are all available and visible through the SSMS UI, so even a doofus developer or manager could find them. Fortunately there are Event Notifications! Event notifications are becoming one of my favorite features of SQL Server (keep an eye out for more blogs from me about them). They are practically unknown and heinously underutilized.  They are also a great gateway drug to using Service Broker, another great but underutilized feature. Hopefully this will get you to start using them, or at least your enemies in the office will once they read this, and then you'll have to learn them in order to fix things. So here's the setup: USE msdb; GO CREATE PROCEDURE dbo.SA_LOGIN_PRIORITY_act WITH ENCRYPTION AS DECLARE @x XML, @message nvarchar(max); RECEIVE @x=CAST(message_body AS XML) FROM SA_LOGIN_PRIORITY_q; IF @x.value('(//LoginName)[1]','sysname')=N'sa' AND @x.value('(//ApplicationName)[1]','sysname') NOT LIKE N'SQL Agent%' BEGIN -- interesting activation procedure stuff goes here END GO CREATE QUEUE SA_LOGIN_PRIORITY_q WITH STATUS=ON, RETENTION=OFF, ACTIVATION (PROCEDURE_NAME=dbo.SA_LOGIN_PRIORITY_act, MAX_QUEUE_READERS=1, EXECUTE AS OWNER); CREATE SERVICE SA_LOGIN_PRIORITY_s ON QUEUE SA_LOGIN_PRIORITY_q([http://schemas.microsoft.com/SQL/Notifications/PostEventNotification]); CREATE EVENT NOTIFICATION SA_LOGIN_PRIORITY_en ON SERVER WITH FAN_IN FOR AUDIT_LOGIN TO SERVICE N'SA_LOGIN_PRIORITY_s', N'current database' GO   From top to bottom: Create activation procedure for event notification queue. Create queue to accept messages from event notification, and activate the procedure to process those messages when received. Create service to send messages to that queue. Create event notification on AUDIT_LOGIN events that fire the service. I placed this in msdb as it is an available system database and already has Service Broker enabled by default. You should change this to another database if you can guarantee it won't get dropped. So what to put in place for "interesting activation procedure code"?  Hmmm, so far I haven't addressed Matt's suggestion of writing a lengthy script to send an annoying message: SET @[email protected]('(//HostName)[1]','sysname') + N' tried to log in to server ' + @x.value('(//ServerName)[1]','sysname') + N' as SA at ' + @x.value('(//StartTime)[1]','sysname') + N' using the ' + @x.value('(//ApplicationName)[1]','sysname') + N' program. That''s why you''re getting this message and the attached pornography which' + N' is bloating your inbox and violating company policy, among other things. If you know' + N' this person you can go to their desk and hit them, or use the following SQL to end their session: KILL ' + @x.value('(//SPID)[1]','sysname') + N'; Hopefully they''re in the middle of a huge query that they need to finish right away.' EXEC msdb.dbo.sp_send_dbmail @recipients=N'[email protected]', @subject=N'SA Login Alert', @query_result_width=32767, @body=@message, @query=N'EXEC sp_readerrorlog;', @attach_query_result_as_file=1, @query_attachment_filename=N'UtterlyGrossPorn_SeriouslyDontOpenIt.jpg' I'm not sure I'd call that a lengthy script, but the attachment should get pretty big, and I'm sure the email admins will love storing multiple copies of it.  The nice thing is that this also fires on Dedicated Admin connections! You can even identify DAC connections from the event data returned, I leave that as an exercise for you. You can use that info to change the action taken by the activation procedure, and since it's a stored procedure, it can pretty much do anything! Except KILL the SPID, or SHUTDOWN the server directly.  I'm still working on those.

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• Sevensteps and I are joining forces

  - by Dennis Vroegop

  As of today, I will be partnering with Sevensteps when it comes to developing great Surface, Windows Phone 7 and Windows 7 Touch applications. Below you’ll find the press release we sent out today. I am looking forward to this partnership and expect great things coming from us both in the future!   Dennis Vroegop, Microsoft MVP, joins Sevensteps partner network 1 March 2011, Seattle / Amersfoort Today Dennis Vroegop and Bart Roozendaal, both Microsoft Most Valuable Professional for Microsoft Surface, announce the joining of Dennis Vroegop to the Sevensteps partner network. Dennis and Bart already worked together very closely through the Microsoft MVP connection, but decided to combined their efforts to make the new Microsoft Surface and our solutions for it, a success. Dennis will join the other Sevensteps partners in creating state of the art solutions for Microsoft Surface, Windows Phone 7 and Windows 7 Touch. Dennis brings a vast amount of knowledge about these technologies, as well as his network in the Dutch developer community. With Dennis joining the Sevensteps partner network we bring unique expertise, power and insight in the platforms, that no other company worldwide can offer. This step brings our goal of Sevensteps being the knowledge hub for Microsoft Surface of choice a whole lot closer. About Dennis Vroegop Dennis is a Microsoft MVP for Microsoft Surface and chairman of the Dutch dotNed user group. He has a long history promoting Microsoft Surface in the developer community. Dennis is a regular speaker at local and international conferences and a frequent writer of articles, including but not limited to Microsoft Surface. Dennis has a bachelor’s degree in computer sciences and has spent all of his professional life writing software for the Microsoft platform. About Sevensteps For more information about Sevensteps and Bart Roozendaal please point to http://www.sevensteps.com Tags: surface,wp7,windows touch

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• Metro: Understanding Observables

  - by Stephen.Walther

  The goal of this blog entry is to describe how the Observer Pattern is implemented in the WinJS library. You learn how to create observable objects which trigger notifications automatically when their properties are changed. Observables enable you to keep your user interface and your application data in sync. For example, by taking advantage of observables, you can update your user interface automatically whenever the properties of a product change. Observables are the foundation of declarative binding in the WinJS library. The WinJS library is not the first JavaScript library to include support for observables. For example, both the KnockoutJS library and the Microsoft Ajax Library (now part of the Ajax Control Toolkit) support observables. Creating an Observable Imagine that I have created a product object like this: var product = { name: "Milk", description: "Something to drink", price: 12.33 }; Nothing very exciting about this product. It has three properties named name, description, and price. Now, imagine that I want to be notified automatically whenever any of these properties are changed. In that case, I can create an observable product from my product object like this: var observableProduct = WinJS.Binding.as(product); This line of code creates a new JavaScript object named observableProduct from the existing JavaScript object named product. This new object also has a name, description, and price property. However, unlike the properties of the original product object, the properties of the observable product object trigger notifications when the properties are changed. Each of the properties of the new observable product object has been changed into accessor properties which have both a getter and a setter. For example, the observable product price property looks something like this: price: { get: function () { return this.getProperty(“price”); } set: function (value) { this.setProperty(“price”, value); } } When you read the price property then the getProperty() method is called and when you set the price property then the setProperty() method is called. The getProperty() and setProperty() methods are methods of the observable product object. The observable product object supports the following methods and properties: · addProperty(name, value) – Adds a new property to an observable and notifies any listeners. · backingData – An object which represents the value of each property. · bind(name, action) – Enables you to execute a function when a property changes. · getProperty(name) – Returns the value of a property using the string name of the property. · notify(name, newValue, oldValue) – A private method which executes each function in the _listeners array. · removeProperty(name) – Removes a property and notifies any listeners. · setProperty(name, value) – Updates a property and notifies any listeners. · unbind(name, action) – Enables you to stop executing a function in response to a property change. · updateProperty(name, value) – Updates a property and notifies any listeners. So when you create an observable, you get a new object with the same properties as an existing object. However, when you modify the properties of an observable object, then you can notify any listeners of the observable that the value of a particular property has changed automatically. Imagine that you change the value of the price property like this: observableProduct.price = 2.99; In that case, the following sequence of events is triggered: 1. The price setter calls the setProperty(“price”, 2.99) method 2. The setProperty() method updates the value of the backingData.price property and calls the notify() method 3. The notify() method executes each function in the collection of listeners associated with the price property Creating Observable Listeners If you want to be notified when a property of an observable object is changed, then you need to register a listener. You register a listener by using the bind() method like this: (function () { "use strict"; var app = WinJS.Application; app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { // Simple product object var product = { name: "Milk", description: "Something to drink", price: 12.33 }; // Create observable product var observableProduct = WinJS.Binding.as(product); // Execute a function when price is changed observableProduct.bind("price", function (newValue) { console.log(newValue); }); // Change the price observableProduct.price = 2.99; } }; app.start(); })(); In the code above, the bind() method is used to associate the price property with a function. When the price property is changed, the function logs the new value of the price property to the Visual Studio JavaScript console. The price property is associated with the function using the following line of code: // Execute a function when price is changed observableProduct.bind("price", function (newValue) { console.log(newValue); }); Coalescing Notifications If you make multiple changes to a property – one change immediately following another – then separate notifications won’t be sent. Instead, any listeners are notified only once. The notifications are coalesced into a single notification. For example, in the following code, the product price property is updated three times. However, only one message is written to the JavaScript console. Only the last value assigned to the price property is written to the JavaScript Console window: // Simple product object var product = { name: "Milk", description: "Something to drink", price: 12.33 }; // Create observable product var observableProduct = WinJS.Binding.as(product); // Execute a function when price is changed observableProduct.bind("price", function (newValue) { console.log(newValue); }); // Change the price observableProduct.price = 3.99; observableProduct.price = 2.99; observableProduct.price = 1.99; Only the last value assigned to price, the value 1.99, appears in the console: If there is a time delay between changes to a property then changes result in different notifications. For example, the following code updates the price property every second: // Simple product object var product = { name: "Milk", description: "Something to drink", price: 12.33 }; // Create observable product var observableProduct = WinJS.Binding.as(product); // Execute a function when price is changed observableProduct.bind("price", function (newValue) { console.log(newValue); }); // Add 1 to price every second window.setInterval(function () { observableProduct.price += 1; }, 1000); In this case, separate notification messages are logged to the JavaScript Console window: If you need to prevent multiple notifications from being coalesced into one then you can take advantage of promises. I discussed WinJS promises in a previous blog entry: http://stephenwalther.com/blog/archive/2012/02/22/windows-web-applications-promises.aspx Because the updateProperty() method returns a promise, you can create different notifications for each change in a property by using the following code: // Change the price observableProduct.updateProperty("price", 3.99) .then(function () { observableProduct.updateProperty("price", 2.99) .then(function () { observableProduct.updateProperty("price", 1.99); }); }); In this case, even though the price is immediately changed from 3.99 to 2.99 to 1.99, separate notifications for each new value of the price property are sent. Bypassing Notifications Normally, if a property of an observable object has listeners and you change the property then the listeners are notified. However, there are certain situations in which you might want to bypass notification. In other words, you might need to change a property value silently without triggering any functions registered for notification. If you want to change a property without triggering notifications then you should change the property by using the backingData property. The following code illustrates how you can change the price property silently: // Simple product object var product = { name: "Milk", description: "Something to drink", price: 12.33 }; // Create observable product var observableProduct = WinJS.Binding.as(product); // Execute a function when price is changed observableProduct.bind("price", function (newValue) { console.log(newValue); }); // Change the price silently observableProduct.backingData.price = 5.99; console.log(observableProduct.price); // Writes 5.99 The price is changed to the value 5.99 by changing the value of backingData.price. Because the observableProduct.price property is not set directly, any listeners associated with the price property are not notified. When you change the value of a property by using the backingData property, the change in the property happens synchronously. However, when you change the value of an observable property directly, the change is always made asynchronously. Summary The goal of this blog entry was to describe observables. In particular, we discussed how to create observables from existing JavaScript objects and bind functions to observable properties. You also learned how notifications are coalesced (and ways to prevent this coalescing). Finally, we discussed how you can use the backingData property to update an observable property without triggering notifications. In the next blog entry, we’ll see how observables are used with declarative binding to display the values of properties in an HTML document.

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• Consuming Hello World pagelet in WebCenter Spaces

  - by astemkov

  Introduction The goal of this exercise is to show you how can you use Hello World pagelet that you just created from your web space. Assumptions Let's assume the following: Pagelet Producer is running on http://pageletserver.company.com:8889/pagelets/ WebCenter is running on http://webcenter.company.com:8888/webcenter/ You created Hello_World pagelet as described here. For our exercise we will need a space created. So let's login into WebCenter Portal and create a space called "myspace" using "Portal Site" template: Registering Pagelet Producer with WebCenter portal In order to use our newly created pagelet from WebCenter Spaces, we first need to register Pagelet Producer: Click "Administraion" link on WebCenter toolbar Open the "Configuration" tab Click on "Services" link on the upper-left corner of the page Click on "Portlet Producers" link on the right hand pane of the screen Click on "Register" button Select "Pagelet Producer" radio button and type Producer Name = "MyPageletProducer" Server URL = http://pageletserver.company.com:8889/pagelets/ Click "Test" button If everything is succesful you will see the following screen: Now click "OK'. Pagelet producer is registered: Inserting Hello World pagelet to WebCenter Space Now let's insert Hello World pagelet into "myspace" page: Let's go back to "myspace", click on the icon in a upper-right corner of the page and select "Edit Page" Click on one of the "Add Content" buttons: Select "Mash-Ups": Select "Pagelet Producers: You will see the MyPageletProducer that we just registered: Click on it. You will see the library "MyLib" that contains our "Hello_World" pagelet. Click on "MyLib" and you will see "Hello_World" pagelet. Click on "Add" button, and then "Close" button. Click "Save" button, and then "Close". Now we see that our "Hello World" pagelet is inserted into "myspace" page:

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• Metro: Understanding the default.js File

  - by Stephen.Walther

  The goal of this blog entry is to describe — in painful detail — the contents of the default.js file in a Metro style application written with JavaScript. When you use Visual Studio to create a new Metro application then you get a default.js file automatically. The file is located in a folder named \js\default.js. The default.js file kicks off all of your custom JavaScript code. It is the main entry point to a Metro application. The default contents of the default.js file are included below: // For an introduction to the Blank template, see the following documentation: // http://go.microsoft.com/fwlink/?LinkId=232509 (function () { "use strict"; var app = WinJS.Application; app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { if (eventObject.detail.previousExecutionState !== Windows.ApplicationModel.Activation.ApplicationExecutionState.terminated) { // TODO: This application has been newly launched. Initialize // your application here. } else { // TODO: This application has been reactivated from suspension. // Restore application state here. } WinJS.UI.processAll(); } }; app.oncheckpoint = function (eventObject) { // TODO: This application is about to be suspended. Save any state // that needs to persist across suspensions here. You might use the // WinJS.Application.sessionState object, which is automatically // saved and restored across suspension. If you need to complete an // asynchronous operation before your application is suspended, call // eventObject.setPromise(). }; app.start(); })(); There are several mysterious things happening in this file. The purpose of this blog entry is to dispel this mystery. Understanding the Module Pattern The first thing that you should notice about the default.js file is that the entire contents of this file are enclosed within a self-executing JavaScript function: (function () { ... })(); Metro applications written with JavaScript use something called the module pattern. The module pattern is a common pattern used in JavaScript applications to create private variables, objects, and methods. Anything that you create within the module is encapsulated within the module. Enclosing all of your custom code within a module prevents you from stomping on code from other libraries accidently. Your application might reference several JavaScript libraries and the JavaScript libraries might have variables, objects, or methods with the same names. By encapsulating your code in a module, you avoid overwriting variables, objects, or methods in the other libraries accidently. Enabling Strict Mode with “use strict” The first statement within the default.js module enables JavaScript strict mode: 'use strict'; Strict mode is a new feature of ECMAScript 5 (the latest standard for JavaScript) which enables you to make JavaScript more strict. For example, when strict mode is enabled, you cannot declare variables without using the var keyword. The following statement would result in an exception: hello = "world!"; When strict mode is enabled, this statement throws a ReferenceError. When strict mode is not enabled, a global variable is created which, most likely, is not what you want to happen. I’d rather get the exception instead of the unwanted global variable. The full specification for strict mode is contained in the ECMAScript 5 specification (look at Annex C): http://www.ecma-international.org/publications/files/ECMA-ST/ECMA-262.pdf Aliasing the WinJS.Application Object The next line of code in the default.js file is used to alias the WinJS.Application object: var app = WinJS.Application; This line of code enables you to use a short-hand syntax when referring to the WinJS.Application object: for example,  app.onactivated instead of WinJS.Application.onactivated. The WinJS.Application object  represents your running Metro application. Handling Application Events The default.js file contains an event handler for the WinJS.Application activated event: app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { if (eventObject.detail.previousExecutionState !== Windows.ApplicationModel.Activation.ApplicationExecutionState.terminated) { // TODO: This application has been newly launched. Initialize // your application here. } else { // TODO: This application has been reactivated from suspension. // Restore application state here. } WinJS.UI.processAll(); } }; This WinJS.Application class supports the following events: · loaded – Happens after browser DOMContentLoaded event. After this event, the DOM is ready and you can access elements in a page. This event is raised before external images have been loaded. · activated – Triggered by the Windows.UI.WebUI.WebUIApplication activated event. After this event, the WinRT is ready. · ready – Happens after both loaded and activated events. · unloaded – Happens before application is unloaded. The following default.js file has been modified to capture each of these events and write a message to the Visual Studio JavaScript Console window: (function () { "use strict"; var app = WinJS.Application; WinJS.Application.onloaded = function (e) { console.log("Loaded"); }; WinJS.Application.onactivated = function (e) { console.log("Activated"); }; WinJS.Application.onready = function (e) { console.log("Ready"); } WinJS.Application.onunload = function (e) { console.log("Unload"); } app.start(); })(); When you execute the code above, a message is written to the Visual Studio JavaScript Console window when each event occurs with the exception of the Unload event (presumably because the console is not attached when that event is raised).   Handling Different Activation Contexts The code for the activated handler in the default.js file looks like this: app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { if (eventObject.detail.previousExecutionState !== Windows.ApplicationModel.Activation.ApplicationExecutionState.terminated) { // TODO: This application has been newly launched. Initialize // your application here. } else { // TODO: This application has been reactivated from suspension. // Restore application state here. } WinJS.UI.processAll(); } }; Notice that the code contains a conditional which checks the Kind of the event (the value of e.detail.kind). The startup code is executed only when the activated event is triggered by a Launch event, The ActivationKind enumeration has the following values: · launch · search · shareTarget · file · protocol · fileOpenPicker · fileSavePicker · cacheFileUpdater · contactPicker · device · printTaskSettings · cameraSettings Metro style applications can be activated in different contexts. For example, a camera application can be activated when modifying camera settings. In that case, the ActivationKind would be CameraSettings. Because we want to execute our JavaScript code when our application first launches, we verify that the kind of the activation event is an ActivationKind.Launch event. There is a second conditional within the activated event handler which checks whether an application is being newly launched or whether the application is being resumed from a suspended state. When running a Metro application with Visual Studio, you can use Visual Studio to simulate different application execution states by taking advantage of the Debug toolbar and the new Debug Location toolbar.  Handling the checkpoint Event The default.js file also includes an event handler for the WinJS.Application checkpoint event: app.oncheckpoint = function (eventObject) { // TODO: This application is about to be suspended. Save any state // that needs to persist across suspensions here. You might use the // WinJS.Application.sessionState object, which is automatically // saved and restored across suspension. If you need to complete an // asynchronous operation before your application is suspended, call // eventObject.setPromise(). }; The checkpoint event is raised when your Metro application goes into a suspended state. The idea is that you can save your application data when your application is suspended and reload your application data when your application resumes. Starting the Application The final statement in the default.js file is the statement that gets everything going: app.start(); Events are queued up in a JavaScript array named eventQueue . Until you call the start() method, the events in the queue are not processed. If you don’t call the start() method then the Loaded, Activated, Ready, and Unloaded events are never raised. Summary The goal of this blog entry was to describe the contents of the default.js file which is the JavaScript file which you use to kick off your custom code in a Windows Metro style application written with JavaScript. In this blog entry, I discussed the module pattern, JavaScript strict mode, handling first chance exceptions, WinJS Application events, and activation contexts.

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• Achieving forward compatibility with C++11

  - by mcmcc

  I work on a large software application that must run on several platforms. Some of these platforms support some features of C++11 (e.g. MSVS 2010) and some don't support any (e.g. GCC 4.3.x). I see this situation continuing on for several years (my best guess: 3-5 years). Given that, I would like set up a compatibility interface such that (to whatever degree possible) people can write C++11 code that will still compile with older compilers with a minimum of maintenance. Overall, the goal is to minimize #ifdef's as much as reasonably possible while still enabling basic C++11 syntax/features on the platforms that support them, and provide emulation on the platforms that don't. Let's start with std::move(). The most obvious way to achieve compatibility would be to put something like this in a common header file: #if !defined(HAS_STD_MOVE) namespace std { // C++11 emulation template <typename T> inline T& move(T& v) { return v; } template <typename T> inline const T& move(const T& v) { return v; } } #endif // !defined(HAS_STD_MOVE) This allow people to write things like std::vector<Thing> x = std::move(y); ... with impugnity. It does what they want in C++11 and it does the best it can in C++03. When we finally drop the last of the C++03 compilers, this code can remain as is. However, according to the standard, it is illegal to inject new symbols into the std namespace. That's the theory. My question is, practically speaking, is there any harm in doing this as a way of achieving forward compatibility?

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• CodePlex Daily Summary for Monday, May 10, 2010

  CodePlex Daily Summary for Monday, May 10, 2010New ProjectsAzure Publish-Subscribe: Infrastructure implementing the publish-subscribe pattern in a Windows Azure context. The unit of publishing is an XML document with an optional l...Bakalarska prace SCSF: This work dealing with the technology of Microsoft Software Factories which makes possible an efficient development of applications under MS Windows.Begtostudy-Test: NoteExpress User Tool (NEUT) is a opensource project for NoteExpress user developpers to share their tools and ideas using secondary development. N...CodeReview: Code Review is an open source development tool based on the same approach than FxCop - check the compiled assemblies to enforce good practices rule...CommonFilter: CommonFilter is a subset of the CommonData project, containing just the functions and unit tests for filtering user input.Custom SharepointDesigner Actions: These are a couple of custom actions that i use in sharepoint designer to ease workflow creation.Customer Portal Accelerator for Microsoft Dynamics CRM: The Customer Portal accelerator for Microsoft Dynamics CRM provides businesses the ability to deliver portal capabilities to their customers while ...Danzica Asset Management System: Danzica is an asset management system written in C# that can ingest all of your hardware management systems into a single cohesive portal, giving y...Dot2Silverlight: Dot2Silverlight is a project thats enables to render graphs (written in Dot format) in Silverlight. dot2silverlight, dot, silverlight, C#, graphviz...eGrid_Windows7: This project will include a new platform independent version of the eGrid project. The new version will run on windows 7, using WPF 4 and the Surfa...Game project JAMK: game project on jamkHamcast for multi station coordination: Amateur Radio multiple station operation tends to have loggers and operators striving to get particular information from each other, like what IP a...Headspring Labs: Headspring Labs showcases presentations, samples, and starter kits developed by Headspring.Hongrui Software Development Management Platform: Hongrui Software Development Management Platform 鸿瑞软件开发管理平台(HrSDMP) LinkField: 带有链接的多列 Field migre.me plugin for Seesmic Desktop Platform: migre.me is a brazilian service created to reduces the size of URLs and provides tracking data for shortened links. migre.me plugin for Seesmic ...MISAO: MISAO is a presentation tool.Mongodb Management Studio: Mongodb Management Studio makes it easier for mongodb users (including DBA/Developers/Administrators) to use mongodb. It's developed in ASP.NET 4.0...MS Build for DotNetNuke module development: Automate the task of creating DotNetNuke module PA packs easily using MS Build. Create manifest files, include version #'s automatically and more.Rubyish: C# extensions providing a rubyish syntax to C#SharePoint 2007 Web Parts: The goal of this project is to develop a set of web parts for SharePoint 2007.SharePoint 2010 Web Parts: The goal of this project is to develop a set of web parts for SharePoint 2010.Taxomatic: Taxomatic adds the ability to bulk create Content Types and Columns to a SharePoint site collection. It also caters for the export of the Content T...trackuda: trackuda - track the motion!Web Camera Shooter: Small tool for taking screenshots from web camera and saving them to disk with few image filters as options.Windows API Code Pack Contrib: Extensions to Windows API Code PackNew ReleasesAlan Platform: Technical Preview 1: В центре данного релиза интерфейс, точнее не сам интерфейс, а принцип, по которому он построен. Используя парочку предоставленных свойств, можно со...Begtostudy-Test: Test: Don't Download.BFBC2 PRoCon: PRoCon 0.3.5.1: Release Notes ComingCBM-Command: 2010-05-09: Release Notes - 2010-05-09New Features FILE COPYING Changes Removed the Swap Panels functionality to make room for file copying. It's still in th...CBM-Command: 2010-05-10: Release Notes - 2010-05-10New Features Launching PRG Files New color schemes to better match the C128 and C64 platforms Function Keys Changes ...CommonFilter: CommonFilter0.3D: This initial release of CommonFilter 0.3D is a subset of the CommonData solution that contains just the filter functions.Custom SharepointDesigner Actions: Custom SPD Actions v1.0: This is the first version of the actions library, it includes: Calling a Webservice. Convert a string to a double. Convert a string to an integ...Customer Portal Accelerator for Microsoft Dynamics CRM: Customer Portal Accelerator for Dynamics CRM: The Customer Portal accelerator for Microsoft Dynamics CRM provides businesses the ability to deliver portal capabilities to their customers while ...EPiMVC - EPiServer CMS with ASP.NET MVC: EPiMVC CTP1: First release that mainly addresses routing. The release is described in greater detail here.Helium Frog Animator: Helium Frog 2_06SW3: This is a first release (not for end users as it is not packaged) of mods intended to make the program run easier on netbooks and customised for us...HouseFly controls: HouseFly controls alpha 0.9.8.0: HouseFly controls release 0.9.8.0 alphaID3Tag.Net: ID3TagLib.Net 1.1: The ID3Tag team is proud to release a new version of the ID3tag lib! New features: Removing of ID3V1 and ID3V2 tags Logging operations ( if enab...IT Tycoon: IT Tycoon 0.2.1: Switched to .NET Framework 4 and implemented some Parallel.ForEach calls.MeaMod Playme: MeaMod Playme 0.9.6.5 Bucking Bunny: MeaMod Playme 0.9.6.5 Bucking Bunny Version 0.9.6.5 | Change Set: 48050 -- Added Playme Store -- Added Buy Album -- Added OCDS/Core system -- Adde...migre.me plugin for Seesmic Desktop Platform: migre.me plugin 0.7.0.1: Initial release. Compatible with Seesmic Desktop Platform 0.7.0.772.MISAO: Ver. 5 Alpha(2010-05-10): Alpha versionMultiwfn: multiwfn1.3.2_source: multiwfn1.3.2_sourcePocket Wiki: Desktop Wiki (in dev): Full screen wiki for the PC - supports the same parsers that Pocket Wiki does. Currently in development but usable. Left side shows listbox of all ...Rubyish: alpha: intial buildSevenZipLib Library: v9.13 beta: New release to match 7-zip 9.13 betaShake - C# Make: Shake v0.1.11: Initial version of Shake's services (API), command line parameters (dynamic) now available via ShakeServices class. Introducing interfaces and bas...SharpNotes: SharpNotes (New): This is the release of SharpNotes.SharpNotes: SharpNotes Source (New): This is the source release of SharpNotes.StackOverflow Desktop Client in C# and WPF: StackOverflow Client 1.0: Improved UI Showing votes/answers/views on popups. Bug fixesTaxomatic: Design_0: Design documentThe Movie DB API: TMDB API v1.2: Updated to reflect changes in The Movie DB API.Web Camera Shooter: 1.0.0.0: Initial release. Unstable. Often exception AccessViolation from Touchless SDK.WF Personalplaner: Personalplaner v1.7.29.10127: - Drag und Drop wurde beim Plan und in der Maske unter Plan\Plan-Layout anpassen in die Grids eingefügt - Weitere kleine bugfixesWindows Phone 7 Panorama & Pivot controls: panorama + pivot controls v0.7 (samples included): Panorama and Pivot Controls source code + sample projects. - Phone.Controls.Samples : source code for the PanoramaControl and PivotControl. - Pic...XmlCodeEditor: Release 0.9 Alpha: Release 0.9 AlphaMost Popular ProjectsWBFS ManagerRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesASP.NETPHPExcelMost Active Projectspatterns & practices – Enterprise LibraryRawrThe Information Literacy Education Learning Environment (ILE)Mirror Testing SystemCaliburn: An Application Framework for WPF and SilverlightjQuery Library for SharePoint Web Serviceswhitepatterns & practices - UnityTweetSharpBlogEngine.NET

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• How to cross-reference many character encodings with ASCII OR UTFx?

  - by Garet Claborn

  I'm working with a binary structure, the goal of which is to index the significance of specific bits for any character encoding so that we may trigger events while doing specific checks against the profile. Each character encoding scheme has an associated system record. This record's leading value will be a C++ unsigned long long binary value and signifies the length, in bits, of encoded characters. Following the length are three values, each is a bit field of that length. offset_mask - defines the occurrence of non-printable characters within the min,max of print_mask range_mask - defines the occurrence of the most popular 50% of printable characters print_mask - defines the occurrence value of printable characters The structure of profiles has changed from the op of this question. Most likely I will try to factorize or compress these values in the long-term instead of starting out with ranges after reading more. I have to write some of the core functionality for these main reasons. It has to fit into a particular event architecture we are using, Better understanding of character encoding. I'm about to need it. Integrating into non-linear design is excluding many libraries without special hooks. I'm unsure if there is a standard, cross-encoding mechanism for communicating such data already. I'm just starting to look into how chardet might do profiling as suggested by @amon. The Unicode BOM would be easily enough (for my current project) if all encodings were Unicode. Of course ideally, one would like to support all encodings, but I'm not asking about implementation - only the general case. How can these profiles be efficiently populated, to produce a set of bitmasks which we can use to match strings with common characters in multiple languages? If you have any editing suggestions please feel free, I am a lightweight when it comes to localization, which is why I'm trying to reach out to the more experienced. Any caveats you may be able to help with will be appreciated.

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• Teaching high school kids ASP.NET programming

  - by dotneteer

  During the 2011 Microsoft MVP Global Summit, I have been talking to people about teaching kids ASP.NET programming. I want to work with volunteer organizations to provide kids volunteer opportunities while learning technical skills that can be applied elsewhere. The goal is to teach motivated kids enough skill to be productive with no more than 6 hours of instruction. Based on my prior teaching experience of college extension courses and involvement with high school math and science competitions, I think this is quite doable with classic ASP but a challenge with ASP.NET. I don’t want to use ASP because it does not provide a good path into the future. After some considerations, I think this is possible with ASP.NET and here are my thoughts: · Create a framework within ASP.NET for kids programming. · Use existing editor. No extra compiler and intelligence work needed. · Using a subset of C# like a scripting language. Teaches data type, expression, statements, if/for/while/switch blocks and functions. Use existing classes but no class creation and OOP. · Linear rendering model. No complicated life cycle. · Bare-metal html with some MVC style helpers for widget creation; ASP.NET control is optional. I want to teach kids to understand something and avoid black boxes as much as possible. · Use SQL for CRUD with a helper class. Again, I want to teach understanding rather than black boxes. · Provide a template to encourage clean separation of concern. · Provide a conversion utility to convert the code that uses template to ASP.NET MVC. This will allow kids with AP Computer Science knowledge to step up to ASP.NET MVC. Let me know if you have thoughts or can help.

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• OpenSSH 5.9p1 on Ubuntu 11.10

  - by Michal Burak

  I want to build a deb package with the latest version of openssh from source. Then I want to install it on my machine. I am running: Linux Ubuntu-1110-oneiric-64-minimal 3.0.0-12-server #20-Ubuntu SMP Fri Oct 7 16:36:30 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux To achieve my goal I do: wget ftp://ftp.openbsd.com/pub/OpenBSD/OpenSSH/portable/openssh-5.9p1.tar.gz wget ftp://ftp.openbsd.com/pub/OpenBSD/OpenSSH/portable/openssh-5.9p1.tar.gz.asc gpg openssh-5.9p1.tar.gz.asc apt-get build-dep openssh-server openssh-client apt-get source openssh-server cd openssh-5.8p1/ uupdate -v 5.9p1 /root/packages/openssh/openssh-5.9p1.tar.gz cd ../openssh-5.9p1 dpkg-buildpackage -us -uc -nc But I get an error: make[1]: Entering directory `/root/packages/openssh/openssh-5.9p1' rm -f debian/tmp/etc/ssh/sshd_config dh_install -Nopenssh-client-udeb -Nopenssh-server-udeb --fail-missing cp: cannot stat `debian/tmp/usr/bin/ssh-vulnkey': No such file or directory dh_install: cp -a debian/tmp/usr/bin/ssh-vulnkey debian/openssh-client//usr/bin/ returned exit code 1 make[1]: *** [override_dh_install] Error 2 make[1]: Leaving directory `/root/packages/openssh/openssh-5.9p1' make: *** [binary] Error 2 dpkg-buildpackage: error: debian/rules binary gave error exit status 2 Any ideas what do I do to make this work?

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• Track a Adobe Flash app hosted on multiple domains with Google Analytics

  - by roberkules

  I'm working on a flash app that's gonna be distributed to more and more partners (and obviously domains). It needs to be tracked aggregated and also separately. I implemented Google Analytics using gaforflash, tracking virtual pageviews and events inside the flash app. What I want to achieve: View an aggregated report of all partners. Identify the partner not by the domain (where the flash is used), but by a partnerID. Each partner needs access to the report of his domain. (no admin rights needed) I came up with this solution: Using only one "Web property" in Google Analytics. UA-XXXXXX-4 .example.com Set a custom/virtual hostname per partner. (GA's "utmhn" parameter) partner1.example.com partner2.example.com Create a profile for each partner, setting the filter to include only the relevant "subdomain" Problems that came up: The gaforflash library doesn't support overriding the host name. Possible workaround: The gaforflash source code is available, so I could add the functionality. Any goal from the "master" profile is not copied to the partners profile. profile 1: include traffic from hostname ^partner1\. profile 2: include traffic from hostname ^partner2\. Is it (very) bad to fake the hostname? Are there better approaches? Or what improvements could you think of? UPDATE: I'm looking primarily for a solid data structure inside Google Analytics regardless of the flash implementation. The only limitations: We need an aggregated view across all partners Our partners need to have access to their subset of data We want to identify the partner by a custom partnerID, not the domain

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• Oracle’s Java Community Outreach Plan

  - by Yolande Poirier

  As the steward of Java, Oracle recognizes the importance and value of the Java community, and the relevant role it plays in keeping Java the largest, most vibrant developer community in the world.   In order to increase Oracle’s touch with Java developers worldwide, we are shifting our focus from a flagship JavaOne event followed by several regional JavaOne conferences, to a new outreach model which continues with the JavaOne flagship event, as well as a mix of online content, regional Java Tours, and regional 3rd party event participation.  1. JavaOne JavaOne continues to remain the premier hub for Java developers where you are given the opportunity to improve your Java technical skills, and interact with other members of the Java community. JavaOne is centered on open collaboration and sharing, and Oracle will continue to invest in JavaOne as a unique stand-alone event for the Java community. Oracle recognizes that many developers cannot attend JavaOne in person, therefore Oracle will share the wealth of the unique event material to those developers through a new and easy-to-access online Java program. While online JavaOne content cannot address the importance of actual face-to-face community/developer engagements and networking, online content does aide in extending the Java technical learning opportunity to a broader collection of developers. 2. Java Developer Day Tours Oracle will execute regional Java Developer Days with recognized Java User Groups (JUGs) with participation from Java Evangelist and Java Champions. This allows local, regional specific Java topics to be addressed both by Oracle and the Java community. In addition, Oracle will deliver more virtual technical content programs to reach developers where an existing JUG may not have a presence. 3. Sponsorship of Community-Driven Regional Events/Conferences Oracle also recognizes that improved community dialog and relations are achievable by continued Oracle sponsorship and onsite participation at both established/well-recognized 3rd party events and new emerging/growing 3rd party events. Oracle’s ultimate goal is to be an even better steward for Java by reaching more of the Java ecosystem with face-to-face and online community engagements. We look forward to planning tours and events with you, members of the Java community.

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• Installing SharePoint 2010 and PowerPivot for SharePoint on Windows 7

  - by smisner

  Many people like me want (or need) to do their business intelligence development work on a laptop. As someone who frequently speaks at various events or teaches classes on all subjects related to the Microsoft business intelligence stack, I need a way to run multiple server products on my laptop with reasonable performance. Once upon a time, that requirement meant only that I had to load the current version of SQL Server and the client tools of choice. In today's post, I'll review my latest experience with trying to make the newly released Microsoft BI products work with a Windows 7 operating system. The entrance of Microsoft Office SharePoint Server 2007 into the BI stack complicated matters and I started using Virtual Server to establish a "suitable" environment. As part of the team that delivered a lot of education as part of the Yukon pre-launch activities (that would be SQL Server 2005 for the uninitiated), I was working with four - yes, four - virtual servers. That was a pretty brutal workload for a 2GB laptop, which worked if I was very, very careful. It could also be a finicky and unreliable configuration as I learned to my dismay at one TechEd session several years ago when I had to reboot a very carefully cached set of servers just minutes before my session started. Although it worked, it came back to life very, very slowly much to the displeasure of the audience. They couldn't possibly have been less pleased than me. At that moment, I resolved to get the beefiest environment I could afford and consolidate to a single virtual server. Enter the 4GB 64-bit laptop to preserve my sanity and my livelihood. Likewise, for SQL Server 2008, I managed to keep everything within a single virtual server and I could function reasonably well with this approach. Now we have SQL Server 2008 R2 plus Office SharePoint Server 2010. That means a 64-bit operating system. Period. That means no more Virtual Server. That means I must use Hyper-V or another alternative. I've heard alternatives exist, but my few dabbles in this area did not yield positive results. It might have been just me having issues rather than any failure of those technologies to adequately support the requirements. My first run at working with the new BI stack configuration was to set up a 64-bit 4GB laptop with a dual-boot to run Windows Server 2008 R2 with Hyper-V. However, I was generally not happy with running Windows Server 2008 R2 on my laptop. For one, I couldn't put it into sleep mode, which is helpful if I want to prepare for a presentation beforehand and then walk to the podium without the need to hold my laptop in its open state along the way (my strategy at the TechEd session long, long ago). Secondly, it was finicky with projectors. I had issues from time to time and while I always eventually got it to work, I didn't appreciate those nerve-wracking moments wondering whether this would be the time that it wouldn't work. Somewhere along the way, I learned that it was possible to load SharePoint 2010 in a Windows 7 which piqued my interest. I had just acquired a new laptop running Windows 7 64-bit, and thought surely running the BI stack natively on my laptop must be better than running Hyper-V. (I have not tried booting to Hyper-V VHD yet, but that's on my list of things to try so the jury of one is still out on this approach.) Recently, I had to build up a server with the RTM versions of SQL Server 2008 R2 and Sharepoint Server 2010 and decided to follow suit on my Windows 7 Ultimate 64-bit laptop. The process is slightly different, but I'm happy to report that it IS possible, although I had some fits and starts along the way. DISCLAIMER: These products are NOT intended to be run in production mode on the Windows 7 operating system. The configuration described in this post is strictly for development or learning purposes and not supported by Microsoft. If you have trouble, you will NOT get help from them. I might be able to help, but I provide no guarantees of my ability or availablity to help. I won't provide the step-by-step instructions in this post as there are other resources that provide these details, but I will provide an overview of my approach, point you to the relevant resources, describe some of the problems I encountered, and explain how I addressed those problems to achieve my desired goal. Because my goal was not simply to set up SharePoint Server 2010 on my laptop, but specifically PowerPivot for SharePoint, I started out by referring to the installation instructions at the PowerPiovt-Info site, but mainly to confirm that I was performing steps in the proper sequence. I didn't perform the steps in Part 1 because those steps are applicable only to a server operating system which I am not running on my laptop. Then, the instructions in Part 2, won't work exactly as written for the same reason. Instead, I followed the instructions on MSDN, Setting Up the Development Environment for SharePoint 2010 on Windows Vista, Windows 7, and Windows Server 2008. In general, I found the following differences in installation steps from the steps at PowerPivot-Info: You must copy the SharePoint installation media to the local drive so that you can edit the config.xml to allow installation on a Windows client. You also have to manually install the prerequisites. The instructions provides links to each item that you must manually install and provides a command-line instruction to execute which enables required Windows features. I will digress for a moment to save you some grief in the sequence of steps to perform. I discovered later that a missing step in the MSDN instructions is to install the November CTP Reporting Services add-in for SharePoint. When I went to test my SharePoint site (I believe I tested after I had a successful PowerPivot installation), I ran into the following error: Could not load file or assembly 'RSSharePointSoapProxy, Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91' or one of its dependencies. The system cannot find the file specified. I was rather surprised that Reporting Services was required. Then I found an article by Alan le Marquand, Working Together: SQL Server 2008 R2 Reporting Services Integration in SharePoint 2010,that instructed readers to install the November add-in. My first reaction was, "Really?!?" But I confirmed it in another TechNet article on hardware and software requirements for SharePoint Server 2010. It doesn't refer explicitly to the November CTP but following the link took me there. (Interestingly, I retested today and there's no longer any reference to the November CTP. Here's the link to download the latest and greatest Reporting Services Add-in for SharePoint Technologies 2010.) You don't need to download the add-in anymore if you're doing a regular server-based installation of SharePoint because it installs as part of the prerequisites automatically. When it was time to start the installation of SharePoint, I deviated from the MSDN instructions and from the PowerPivot-Info instructions: On the Choose the installation you want page of the installation wizard, I chose Server Farm. On the Server Type page, I chose Complete. At the end of the installation, I did not run the configuration wizard. Returning to the PowerPivot-Info instructions, I tried to follow the instructions in Part 3 which describe installing SQL Server 2008 R2 with the PowerPivot option. These instructions tell you to choose the New Server option on the Setup Role page where you add PowerPivot for SharePoint. However, I ran into problems with this approach and got installation errors at the end. It wasn't until much later as I was investigating an error that I encountered Dave Wickert's post that installing PowerPivot for SharePoint on Windows 7 is unsupported. Uh oh. But he did want to hear about it if anyone succeeded, so I decided to take the plunge. Perseverance paid off, and I can happily inform Dave that it does work so far. I haven't tested absolutely everything with PowerPivot for SharePoint but have successfully deployed a workbook and viewed the PowerPivot Management Dashboard. I have not yet tested the data refresh feature, but I have installed. Continue reading to see how I accomplished my objective. I unintalled SQL Server 2008 R2 and started again. I had different problems which I don't recollect now. However, I uninstalled again and approached installation from a different angle and my next attempt succeeded. The downside of this approach is that you must do all of the things yourself that are done automatically when you install PowerPivot as a new server. Here are the steps that I followed: Install SQL Server 2008 R2 to get a database engine instance installed. Run the SharePoint configuration wizard to set up the SharePoint databases. In Central Administration, create a Web application using classic mode authentication as per a TechNet article on PowerPivot Authentication and Authorization. Then I followed the steps I found at How to: Install PowerPivot for SharePoint on an Existing SharePoint Server. Especially important to note - you must launch setup by using Run as administrator. I did not have to manually deploy the PowerPivot solution as the instructions specify, but it's good to know about this step because it tells you where to look in Central Administration to confirm a successful deployment. I did spot some incorrect steps in the instructions (at the time of this writing) in How To: Configure Stored Credentials for PowerPivot Data Refresh. Specifically, in the section entitled Step 1: Create a target application and set the credentials, both steps 10 and 12 are incorrect. They tell you to provide an actual Windows user name and password on the page where you are simply defining the prompts for your application in the Secure Store Service. To add the Windows user name and password that you want to associate with the application - after you have successfully created the target application - you select the target application and then click Set credentials in the ribbon. Lastly, I followed the instructions at How to: Install Office Data Connectivity Components on a PowerPivot server. However, I have yet to test this in my current environment. I did have several stops and starts throughout this process and edited those out to spare you from reading non-essential information. I believe the explanation I have provided here accurately reflect the steps I followed to produce a working configuration. If you follow these steps and get a different result, please let me know so that together we can work through the issue and correct these instructions. I'm sure there are many other folks in the Microsoft BI community that will appreciate the ability to set up the BI stack in a Windows 7 environment for development or learning purposes. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• DTrace for Oracle Linux news: new beta release and conference appearances

  - by Lenz Grimmer

  A new set of RPM packages of our port of DTrace for Linux has just been published on the Unbreakable Linux Network. This is another beta release of our ongoing development effort to bring the DTrace framework to Linux. This release includes the following changes: The packages are now based on the final public release of the Unbreakable Enterprise Kernel Release 2 (2.6.39). The previous beta drop was based on a development version of the 2.6.39 kernel; there is no new functionality specific to DTrace in this release. The primary goal was to get the code base in sync with the released kernel version. Based on the feedback we received from some users in how their applications interact with dtrace, libdtrace is now a shared library. However, the API/ABI is not fully stabilized yet and may be subject to change. As a result of the ongoing QA testing, some test cases were reorganized into their own subdirectories, which allows running the test suite in a more fine-grained manner. As reminder, we have a dedicated Forum for DTrace on Linux, to discuss your experiences with this release. This week, the Linux DTrace team also attendeded the second dtrace.conf in San Francisco, to talk about their work. The sessions were streamed live and recordings are also available. You can watch Oracle's Kris Van Hees' talk below: Video streaming by Ustream We would like to thank the dtrace.conf organizers for the speaking opportunity and for organizing this event! This Wednesday (April 4th), Kris and Elena Zannoni also spoke on this topic at the Linux Foundation Collaboration Summit 2012 in San Francisco, CA. The slides are now available for download (PDF).

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• A Model for Planning Your Oracle BPM 10g Migration by Kris Nelson

  - by JuergenKress

  As the Oracle SOA Suite and BPM Suite 12c products enter beta, many of our clients are starting to discuss migrating from the Oracle 10g or prior platforms. With the BPM Suite 11g, Oracle introduced a major change in architecture with a strong focus on integration with SOA and an entirely new technology stack. In addition, there were fresh new UIs and a renewed business focus with an improved Process Composer and features like Adaptive Case Management. While very beneficial to both technology and the business, the fundamental change in architecture does pose clear migration challenges for clients who have made investments in the 10g platform. Some of the key challenges facing 10g customers include: Managing in-process instance migration and running multiple process engines Migration of User Interfaces and other code within the environment that may not be automated Growing or finding technical staff with both 10g and 12c experience Managing migration projects while continuing to move the business forward and meet day-to-day responsibilities As a former practitioner in a mixed 10g/11g shop, I wrestled with many of these challenges as we tried to plan ahead for the migration. Luckily, there is migration tooling on the way from Oracle and several approaches you can use in planning your migration efforts. In addition, you already have a defined and visible process on the current platform, which will be invaluable as you migrate.  A Migration ModelThis model presents several options across a value and investment spectrum. The goal of the AVIO Migration Model is to kick-start discussions within your company and assist in creating a plan of action to take advantage of the new platform. As with all models, this is a framework for discussion and certain processes or situations may not fit. Please contact us if you have specific questions or want to discuss migrations efforts in your situation. Read the complete article here. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Technorati Tags: Kris Nelson,ACM,Adaptive Case Management,Community,Oracle SOA,Oracle BPM,OPN,Jürgen Kress

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• SOA &amp; Application Grid Specialization &ndash; 6 steps to success &ndash; part 1 OMM

  - by Jürgen Kress

  SOA Specialization – Oracle Open Market Model (OMM) Dear Application Grid SOA Partners, Or goal is to SOA Specialize you, in the next weeks we will inform you in a series how you can achieve SOA Specialization. Specialization is key the be recognized by Oracle and to be preferred by our Customers. The first step to become SOA Specialized is to proof 2 transactions. You can either resell, co-sell or referral – as a proof point we do use our Open Market Model (OMM). To create your account go to our new Partner Portal: go to login of your OPN-Homepage: http://oraclepartnernetwork.oracle.com click on: "Sales" "Create a PRM User Account" Enter your User ID: Enter Company Identifier: ((please ask your OPN IC)) Finish Wait for a Confirmation Email If you need OMM support please contact out dedicated team: Nordics  please ask: [email protected] Portugal, Spain please ask: [email protected] Austria, Belgium, Germany, Luxembourg, Netherlands, Switzerland, United Arab Emirates, United Kingdom please ask: [email protected] For more information about OMM watch our on-demand webcast “Recognising the Value of Partners: Register Oracle Deals through the Open Market Model (OMM)”. Become SOA Specialized today SOA Specialized & Application Grid Specialized Create your references, create your OMM Entry, take the SOA Sales assessment, take the SOA Pre-Sales assessment, take the Support assessment and register for the SOA Implementation assessment. For more information on Specialization please visit our OPN Specialized Webcast Series To get support on Specialization please contact the Partner Business Centers.   SOA Specialized Application Grid Specialized Proof 2 transactions with OMM Proof 2 transactions with OMM Create your 2 references Create your 2 references SOA Sales assessment 3, Oracle Application Grid Sales Specialist  SOA Pre-Sales assessment 3 Oracle Application Grid PreSales Specialist Support assessment 1 Support assessment 2 SOA Implementation assessment 4 Application Grid Implementation assessment 4

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• SQLAuthority News – Download Whitepaper – SQL Server 2008 R2 Analysis Services Operations Guide

  - by pinaldave

  SQL Server Analysis Service (SSAS) has been always interesting subject for research. Analysis Services cubes are a very powerful tool in the hands of the business intelligence (BI) developer. They provide an easy way to expose even large data models directly to business users. Microsoft has published very informative white paper on Analysis Services Operations Guide. This white paper is authored by Thomas Kejser, John Sirmon, and Denny Lee. In this guide you will find information on how to test and run Microsoft SQL Server Analysis Services in SQL Server 2005, SQL Server 2008, and SQL Server 2008 R2 in a production environment. The focus of this guide is how you can test, monitor, diagnose, and remove production issues on even the largest scaled cubes. This paper also provides guidance on how to configure the server for best possible performance. It is the goal of this guide to make your operations processes as painless as possible, and to have you run with the best possible performance without any additional development effort to your deployed cubes. In this guide, you will learn how to get the best out of your existing data model by making changes transparent to the data model and by making configuration changes that improve the user experience of the cube. Download SQL Server 2008 R2 Analysis Services Operations Guide Note: Abstract taken white paper. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, SQL White Papers, SQLAuthority News, T SQL, Technology

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• Bruce Lee Software development.

  - by DesigningCode

  "Styles tend to not only separate men - because they have their own doctrines and then the doctrine became the gospel truth that you cannot change. But if you do not have a style, if you just say: Well, here I am as a human being, how can I express myself totally and completely? Now, that way you won't create a style, because style is a crystallization. That way, it's a process of continuing growth."- Bruce Lee This is kind of how I see software development. What I enjoyed in the the early days of Agile, things seemed very dynamic, people were working out all manner of ways of doing things. It was technique oriented, it was very fluid and people were finding all kinds of good ways of doing things.  Now when I look at the world of “Agile” it seems more crystalized.  In fact that seemed to be a goal, to crystalize the goodness so everyone can share.   I think mainly because it seems a heck of a lot easier to market.  People are more willing to accept a well defined doctrine and drink the Kool Aid.   Its more “corporate” or “professional”. But the process of crystalizing the goodness actually makes it bad.   But luckily in the world of software development there are still many people who are more focused on “how can I express myself totally and completely”.   We are seeing expressive languages, expressive frameworks, tooling that helps you to better express yourself, design techniques that allow you to better express your intent.    I love that stuff! So beware, be very cautious of anyone offering you new age wisdom based on crystals!

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• My Expert F# Book has now arrived!

  - by MarkPearl

  So it has finally arrived from Amazon. Expert F# by Don Syme, Adam Granicz & Antonio Cisternino. I got a note from the post office yesterday that I needed to collect a package from their offices. After paying a 10% customs fee (that I wasn’t expecting) I had my new Yellow & Black F# Book… it’s so shinny. Trust my luck though – I have a few university assignments due this week as well as a crazy week of work so it has been sitting on my desk for a day and I haven’t managed to get into it. Eventually I managed to take a few minutes this evening to page through it and it looks really good. I can’t wait! So my goal this week is to cover Chapter 2 (by the end of the weekend) and put the appropriate posts up. F# is slowly working on me but I am keen to get a deeper understanding of the language which I am hoping this book will help me achieve.

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• MSDN article on jQuery Mobile

  - by Wallym

  My article on jQuery Mobile has been published.  Please check it out.There’s no doubt about it. Wherever developers look and whoever they talk to, mobile is at the top of the list. Talk to a C-level executive, and the conversation turns to mobile, and the question “How do I get me some of that?” comes up. Talk to other developers, and they tell you they’re targeting mobile devices. Mobile has become a big deal as smartphones have taken hold in the consumer marketplace.In the years leading up to the current focus on mobile applications and devices, Web developers have been adding more and more client-side functionality to their applications. You can see this in the use of client-side JavaScript libraries like jQuery.With the growth of the market for mobile devices, the ability to create applications that run across platforms is very important for developers and for businesses that are trying to keep their expenses in check. There are a set of applications, mostly in the area of content consumption (think Amazon.com), that run well in a mobile Web browser. Unfortunately, there are differences between Web browsers on various mobile devices. The goal of the recently introduced jQuery Mobile (jQM) library is to provide cross-browser support to allow developers to build applications that can run across the various mobile Web browsers and provide the same—or at least a very similar—user interface.The jQuery Mobile library was introduced in an alpha release in the fall of 2010 and released to manufacturing in November 2011. At the time of this writing, the current version of jQuery Mobile is 1.1.1. By the time you read this, jQuery Mobile will almost certainly have reached version 1.2.0. The library has been embraced by Microsoft, Adobe and other companies for mobile Web development. In August 2011, jQM had 32 percent market share compared with other mobile JavaScript frameworks such as iWebKit and jQTouch. This market share is impressive given that it started from zero little more than 12 months ago, and the 1.0 release is the first officially supported release.

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• Keystone Correction using 3D-Points of Kinect

  - by philllies

  With XNA, I am displaying a simple rectangle which is projected onto the floor. The projector can be placed at an arbitrary position. Obviously, the projected rectangle gets distorted according to the projectors position and angle. A Kinect scans the floor looking for the four corners. Now my goal is to transform the original rectangle such that the projection is no longer distorted by basically pre-warping the rectangle. My first approach was to do everything in 2D: First compute a perspective transformation (using OpenCV's warpPerspective()) from the scanned points to the internal rectangle's points und apply the inverse to the rectangle. This seemed to work but was too slow as it couldn't be rendered on the GPU. The second approach was to do everything in 3D in order to use XNA's rendering features. First, I would display a plane, scan its corners with Kinect and map the received 3D-Points to the original plane. Theoretically, I could apply the inverse of the perspective transformation to the plane, as I did in the 2D-approach. However, in since XNA works with a view and projection matrix, I can't just call a function such as warpPerspective() and get the desired result. I would need to compute the new parameters for the camera's view and projection matrix. Question: Is it possible to compute these parameters and split them into two matrices (view and projection)? If not, is there another approach I could use?

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