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• How to configure apache to basic authentication or allow when ntlm while proxying?

  - by trotzim

  Here is my study case: browser --- apache proxy --- ISA server --- internet The ISA server requires an authentication. The issue is to allow HTTPS through the two proxies. A configuration that works with HTTP is something like this: (yes, I don't want to use ProxyPass but ProxyRequests) <virtualhost *:8080> ... SetEnv auth-proxy-chain on ... ProxyRequests On ProxyRemote * http://isaproxy:80 ... <proxy *> AuthName "ISA server auth" AuthType Basic [here a module to authenticate] require valid-user Allow from all </proxy> ... </virtualhost> The user can authenticate on the apache proxy then the authentication chain is sent to the ISA server that allows the HTTP trafic. But, while the browser switchs to HTTPS, the ISA server "speaks" NTLM and breaks the authentication on the apache proxy. If I try to use the SSPI module (ntlm) with something like this: blablabla <proxy *> AuthName "ISA server auth" AuthType ntlm [ SSPI stuff ] Require valid-user Allow from all </proxy> The apache server reject the authentication (or the ISA server I don't really know). I use wireshark to look at the nominal process while using directly the ISA server as proxy. The first auth-chain is a BASIC type then it switchs to NTLM (and the challenge continues with NTLM). How should I configure apache that it transfers the NTLM authentication to the ISA proxy without checking it(*)? Or to rewrite headers to force BASIC authentication? (*) It seems not to be as easy as it seems...

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• Redirect traffic from 127.0.0.1 to 127.0.0.1 on port 53 to port 5300 with iptables

  - by Zagorax

  I'm running a local dns server on port 5300 to develop a software. I need my machine to use that dns but I wasn't able to tell /etc/resolv.conf to check on a different port. I searched a bit on google and I didn't find a solution. I set 127.0.0.1 as nameserver on /etc/resolv.conf. This is my whole /etc/resolv.conf: nameserver 127.0.0.1 Could you please tell me how can I redirect outbound traffic on port 53 to another port? I tried the following but it didn't work: iptables -t nat -A PREROUTING -p tcp --dport 53 -j DNAT --to 127.0.0.1:5300 iptables -t nat -A PREROUTING -p udp --dport 53 -j DNAT --to 127.0.0.1:5300 Here is the output of iptables -t nat -L -v -n (with suggested rules): Chain PREROUTING (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 0 0 REDIRECT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:53 redir ports 5300 0 0 REDIRECT udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:53 redir ports 5300 Chain POSTROUTING (policy ACCEPT 302 packets, 19213 bytes) pkts bytes target prot opt in out source destination Chain OUTPUT (policy ACCEPT 302 packets, 19213 bytes) pkts bytes target prot opt in out source destination

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• The Incremental Architect&rsquo;s Napkin - #5 - Design functions for extensibility and readability

  - by Ralf Westphal

  Originally posted on: http://geekswithblogs.net/theArchitectsNapkin/archive/2014/08/24/the-incremental-architectrsquos-napkin---5---design-functions-for.aspx The functionality of programs is entered via Entry Points. So what we´re talking about when designing software is a bunch of functions handling the requests represented by and flowing in through those Entry Points. Designing software thus consists of at least three phases: Analyzing the requirements to find the Entry Points and their signatures Designing the functionality to be executed when those Entry Points get triggered Implementing the functionality according to the design aka coding I presume, you´re familiar with phase 1 in some way. And I guess you´re proficient in implementing functionality in some programming language. But in my experience developers in general are not experienced in going through an explicit phase 2. “Designing functionality? What´s that supposed to mean?” you might already have thought. Here´s my definition: To design functionality (or functional design for short) means thinking about… well, functions. You find a solution for what´s supposed to happen when an Entry Point gets triggered in terms of functions. A conceptual solution that is, because those functions only exist in your head (or on paper) during this phase. But you may have guess that, because it´s “design” not “coding”. And here is, what functional design is not: It´s not about logic. Logic is expressions (e.g. +, -, && etc.) and control statements (e.g. if, switch, for, while etc.). Also I consider calling external APIs as logic. It´s equally basic. It´s what code needs to do in order to deliver some functionality or quality. Logic is what´s doing that needs to be done by software. Transformations are either done through expressions or API-calls. And then there is alternative control flow depending on the result of some expression. Basically it´s just jumps in Assembler, sometimes to go forward (if, switch), sometimes to go backward (for, while, do). But calling your own function is not logic. It´s not necessary to produce any outcome. Functionality is not enhanced by adding functions (subroutine calls) to your code. Nor is quality increased by adding functions. No performance gain, no higher scalability etc. through functions. Functions are not relevant to functionality. Strange, isn´t it. What they are important for is security of investment. By introducing functions into our code we can become more productive (re-use) and can increase evolvability (higher unterstandability, easier to keep code consistent). That´s no small feat, however. Evolvable code can hardly be overestimated. That´s why to me functional design is so important. It´s at the core of software development. To sum this up: Functional design is on a level of abstraction above (!) logical design or algorithmic design. Functional design is only done until you get to a point where each function is so simple you are very confident you can easily code it. Functional design an logical design (which mostly is coding, but can also be done using pseudo code or flow charts) are complementary. Software needs both. If you start coding right away you end up in a tangled mess very quickly. Then you need back out through refactoring. Functional design on the other hand is bloodless without actual code. It´s just a theory with no experiments to prove it. But how to do functional design? An example of functional design Let´s assume a program to de-duplicate strings. The user enters a number of strings separated by commas, e.g. a, b, a, c, d, b, e, c, a. And the program is supposed to clear this list of all doubles, e.g. a, b, c, d, e. There is only one Entry Point to this program: the user triggers the de-duplication by starting the program with the string list on the command line C:\>deduplicate "a, b, a, c, d, b, e, c, a" a, b, c, d, e …or by clicking on a GUI button. This leads to the Entry Point function to get called. It´s the program´s main function in case of the batch version or a button click event handler in the GUI version. That´s the physical Entry Point so to speak. It´s inevitable. What then happens is a three step process: Transform the input data from the user into a request. Call the request handler. Transform the output of the request handler into a tangible result for the user. Or to phrase it a bit more generally: Accept input. Transform input into output. Present output. This does not mean any of these steps requires a lot of effort. Maybe it´s just one line of code to accomplish it. Nevertheless it´s a distinct step in doing the processing behind an Entry Point. Call it an aspect or a responsibility - and you will realize it most likely deserves a function of its own to satisfy the Single Responsibility Principle (SRP). Interestingly the above list of steps is already functional design. There is no logic, but nevertheless the solution is described - albeit on a higher level of abstraction than you might have done yourself. But it´s still on a meta-level. The application to the domain at hand is easy, though: Accept string list from command line De-duplicate Present de-duplicated strings on standard output And this concrete list of processing steps can easily be transformed into code:static void Main(string[] args) { var input = Accept_string_list(args); var output = Deduplicate(input); Present_deduplicated_string_list(output); } Instead of a big problem there are three much smaller problems now. If you think each of those is trivial to implement, then go for it. You can stop the functional design at this point. But maybe, just maybe, you´re not so sure how to go about with the de-duplication for example. Then just implement what´s easy right now, e.g.private static string Accept_string_list(string[] args) { return args[0]; } private static void Present_deduplicated_string_list( string[] output) { var line = string.Join(", ", output); Console.WriteLine(line); } Accept_string_list() contains logic in the form of an API-call. Present_deduplicated_string_list() contains logic in the form of an expression and an API-call. And then repeat the functional design for the remaining processing step. What´s left is the domain logic: de-duplicating a list of strings. How should that be done? Without any logic at our disposal during functional design you´re left with just functions. So which functions could make up the de-duplication? Here´s a suggestion: De-duplicate Parse the input string into a true list of strings. Register each string in a dictionary/map/set. That way duplicates get cast away. Transform the data structure into a list of unique strings. Processing step 2 obviously was the core of the solution. That´s where real creativity was needed. That´s the core of the domain. But now after this refinement the implementation of each step is easy again:private static string[] Parse_string_list(string input) { return input.Split(',') .Select(s => s.Trim()) .ToArray(); } private static Dictionary<string,object> Compile_unique_strings(string[] strings) { return strings.Aggregate( new Dictionary<string, object>(), (agg, s) => { agg[s] = null; return agg; }); } private static string[] Serialize_unique_strings( Dictionary<string,object> dict) { return dict.Keys.ToArray(); } With these three additional functions Main() now looks like this:static void Main(string[] args) { var input = Accept_string_list(args); var strings = Parse_string_list(input); var dict = Compile_unique_strings(strings); var output = Serialize_unique_strings(dict); Present_deduplicated_string_list(output); } I think that´s very understandable code: just read it from top to bottom and you know how the solution to the problem works. It´s a mirror image of the initial design: Accept string list from command line Parse the input string into a true list of strings. Register each string in a dictionary/map/set. That way duplicates get cast away. Transform the data structure into a list of unique strings. Present de-duplicated strings on standard output You can even re-generate the design by just looking at the code. Code and functional design thus are always in sync - if you follow some simple rules. But about that later. And as a bonus: all the functions making up the process are small - which means easy to understand, too. So much for an initial concrete example. Now it´s time for some theory. Because there is method to this madness ;-) The above has only scratched the surface. Introducing Flow Design Functional design starts with a given function, the Entry Point. Its goal is to describe the behavior of the program when the Entry Point is triggered using a process, not an algorithm. An algorithm consists of logic, a process on the other hand consists just of steps or stages. Each processing step transforms input into output or a side effect. Also it might access resources, e.g. a printer, a database, or just memory. Processing steps thus can rely on state of some sort. This is different from Functional Programming, where functions are supposed to not be stateful and not cause side effects.[1] In its simplest form a process can be written as a bullet point list of steps, e.g. Get data from user Output result to user Transform data Parse data Map result for output Such a compilation of steps - possibly on different levels of abstraction - often is the first artifact of functional design. It can be generated by a team in an initial design brainstorming. Next comes ordering the steps. What should happen first, what next etc.? Get data from user Parse data Transform data Map result for output Output result to user That´s great for a start into functional design. It´s better than starting to code right away on a given function using TDD. Please get me right: TDD is a valuable practice. But it can be unnecessarily hard if the scope of a functionn is too large. But how do you know beforehand without investing some thinking? And how to do this thinking in a systematic fashion? My recommendation: For any given function you´re supposed to implement first do a functional design. Then, once you´re confident you know the processing steps - which are pretty small - refine and code them using TDD. You´ll see that´s much, much easier - and leads to cleaner code right away. For more information on this approach I call “Informed TDD” read my book of the same title. Thinking before coding is smart. And writing down the solution as a bunch of functions possibly is the simplest thing you can do, I´d say. It´s more according to the KISS (Keep It Simple, Stupid) principle than returning constants or other trivial stuff TDD development often is started with. So far so good. A simple ordered list of processing steps will do to start with functional design. As shown in the above example such steps can easily be translated into functions. Moving from design to coding thus is simple. However, such a list does not scale. Processing is not always that simple to be captured in a list. And then the list is just text. Again. Like code. That means the design is lacking visuality. Textual representations need more parsing by your brain than visual representations. Plus they are limited in their “dimensionality”: text just has one dimension, it´s sequential. Alternatives and parallelism are hard to encode in text. In addition the functional design using numbered lists lacks data. It´s not visible what´s the input, output, and state of the processing steps. That´s why functional design should be done using a lightweight visual notation. No tool is necessary to draw such designs. Use pen and paper; a flipchart, a whiteboard, or even a napkin is sufficient. Visualizing processes The building block of the functional design notation is a functional unit. I mostly draw it like this: Something is done, it´s clear what goes in, it´s clear what comes out, and it´s clear what the processing step requires in terms of state or hardware. Whenever input flows into a functional unit it gets processed and output is produced and/or a side effect occurs. Flowing data is the driver of something happening. That´s why I call this approach to functional design Flow Design. It´s about data flow instead of control flow. Control flow like in algorithms is of no concern to functional design. Thinking about control flow simply is too low level. Once you start with control flow you easily get bogged down by tons of details. That´s what you want to avoid during design. Design is supposed to be quick, broad brush, abstract. It should give overview. But what about all the details? As Robert C. Martin rightly said: “Programming is abot detail”. Detail is a matter of code. Once you start coding the processing steps you designed you can worry about all the detail you want. Functional design does not eliminate all the nitty gritty. It just postpones tackling them. To me that´s also an example of the SRP. Function design has the responsibility to come up with a solution to a problem posed by a single function (Entry Point). And later coding has the responsibility to implement the solution down to the last detail (i.e. statement, API-call). TDD unfortunately mixes both responsibilities. It´s just coding - and thereby trying to find detailed implementations (green phase) plus getting the design right (refactoring). To me that´s one reason why TDD has failed to deliver on its promise for many developers. Using functional units as building blocks of functional design processes can be depicted very easily. Here´s the initial process for the example problem: For each processing step draw a functional unit and label it. Choose a verb or an “action phrase” as a label, not a noun. Functional design is about activities, not state or structure. Then make the output of an upstream step the input of a downstream step. Finally think about the data that should flow between the functional units. Write the data above the arrows connecting the functional units in the direction of the data flow. Enclose the data description in brackets. That way you can clearly see if all flows have already been specified. Empty brackets mean “no data is flowing”, but nevertheless a signal is sent. A name like “list” or “strings” in brackets describes the data content. Use lower case labels for that purpose. A name starting with an upper case letter like “String” or “Customer” on the other hand signifies a data type. If you like, you also can combine descriptions with data types by separating them with a colon, e.g. (list:string) or (strings:string[]). But these are just suggestions from my practice with Flow Design. You can do it differently, if you like. Just be sure to be consistent. Flows wired-up in this manner I call one-dimensional (1D). Each functional unit just has one input and/or one output. A functional unit without an output is possible. It´s like a black hole sucking up input without producing any output. Instead it produces side effects. A functional unit without an input, though, does make much sense. When should it start to work? What´s the trigger? That´s why in the above process even the first processing step has an input. If you like, view such 1D-flows as pipelines. Data is flowing through them from left to right. But as you can see, it´s not always the same data. It get´s transformed along its passage: (args) becomes a (list) which is turned into (strings). The Principle of Mutual Oblivion A very characteristic trait of flows put together from function units is: no functional units knows another one. They are all completely independent of each other. Functional units don´t know where their input is coming from (or even when it´s gonna arrive). They just specify a range of values they can process. And they promise a certain behavior upon input arriving. Also they don´t know where their output is going. They just produce it in their own time independent of other functional units. That means at least conceptually all functional units work in parallel. Functional units don´t know their “deployment context”. They now nothing about the overall flow they are place in. They are just consuming input from some upstream, and producing output for some downstream. That makes functional units very easy to test. At least as long as they don´t depend on state or resources. I call this the Principle of Mutual Oblivion (PoMO). Functional units are oblivious of others as well as an overall context/purpose. They are just parts of a whole focused on a single responsibility. How the whole is built, how a larger goal is achieved, is of no concern to the single functional units. By building software in such a manner, functional design interestingly follows nature. Nature´s building blocks for organisms also follow the PoMO. The cells forming your body do not know each other. Take a nerve cell “controlling” a muscle cell for example:[2] The nerve cell does not know anything about muscle cells, let alone the specific muscel cell it is “attached to”. Likewise the muscle cell does not know anything about nerve cells, let a lone a specific nerve cell “attached to” it. Saying “the nerve cell is controlling the muscle cell” thus only makes sense when viewing both from the outside. “Control” is a concept of the whole, not of its parts. Control is created by wiring-up parts in a certain way. Both cells are mutually oblivious. Both just follow a contract. One produces Acetylcholine (ACh) as output, the other consumes ACh as input. Where the ACh is going, where it´s coming from neither cell cares about. Million years of evolution have led to this kind of division of labor. And million years of evolution have produced organism designs (DNA) which lead to the production of these different cell types (and many others) and also to their co-location. The result: the overall behavior of an organism. How and why this happened in nature is a mystery. For our software, though, it´s clear: functional and quality requirements needs to be fulfilled. So we as developers have to become “intelligent designers” of “software cells” which we put together to form a “software organism” which responds in satisfying ways to triggers from it´s environment. My bet is: If nature gets complex organisms working by following the PoMO, who are we to not apply this recipe for success to our much simpler “machines”? So my rule is: Wherever there is functionality to be delivered, because there is a clear Entry Point into software, design the functionality like nature would do it. Build it from mutually oblivious functional units. That´s what Flow Design is about. In that way it´s even universal, I´d say. Its notation can also be applied to biology: Never mind labeling the functional units with nouns. That´s ok in Flow Design. You´ll do that occassionally for functional units on a higher level of abstraction or when their purpose is close to hardware. Getting a cockroach to roam your bedroom takes 1,000,000 nerve cells (neurons). Getting the de-duplication program to do its job just takes 5 “software cells” (functional units). Both, though, follow the same basic principle. Translating functional units into code Moving from functional design to code is no rocket science. In fact it´s straightforward. There are two simple rules: Translate an input port to a function. Translate an output port either to a return statement in that function or to a function pointer visible to that function. The simplest translation of a functional unit is a function. That´s what you saw in the above example. Functions are mutually oblivious. That why Functional Programming likes them so much. It makes them composable. Which is the reason, nature works according to the PoMO. Let´s be clear about one thing: There is no dependency injection in nature. For all of an organism´s complexity no DI container is used. Behavior is the result of smooth cooperation between mutually oblivious building blocks. Functions will often be the adequate translation for the functional units in your designs. But not always. Take for example the case, where a processing step should not always produce an output. Maybe the purpose is to filter input. Here the functional unit consumes words and produces words. But it does not pass along every word flowing in. Some words are swallowed. Think of a spell checker. It probably should not check acronyms for correctness. There are too many of them. Or words with no more than two letters. Such words are called “stop words”. In the above picture the optionality of the output is signified by the astrisk outside the brackets. It means: Any number of (word) data items can flow from the functional unit for each input data item. It might be none or one or even more. This I call a stream of data. Such behavior cannot be translated into a function where output is generated with return. Because a function always needs to return a value. So the output port is translated into a function pointer or continuation which gets passed to the subroutine when called:[3]void filter_stop_words( string word, Action<string> onNoStopWord) { if (...check if not a stop word...) onNoStopWord(word); } If you want to be nitpicky you might call such a function pointer parameter an injection. And technically you´re right. Conceptually, though, it´s not an injection. Because the subroutine is not functionally dependent on the continuation. Firstly continuations are procedures, i.e. subroutines without a return type. Remember: Flow Design is about unidirectional data flow. Secondly the name of the formal parameter is chosen in a way as to not assume anything about downstream processing steps. onNoStopWord describes a situation (or event) within the functional unit only. Translating output ports into function pointers helps keeping functional units mutually oblivious in cases where output is optional or produced asynchronically. Either pass the function pointer to the function upon call. Or make it global by putting it on the encompassing class. Then it´s called an event. In C# that´s even an explicit feature.class Filter { public void filter_stop_words( string word) { if (...check if not a stop word...) onNoStopWord(word); } public event Action<string> onNoStopWord; } When to use a continuation and when to use an event dependens on how a functional unit is used in flows and how it´s packed together with others into classes. You´ll see examples further down the Flow Design road. Another example of 1D functional design Let´s see Flow Design once more in action using the visual notation. How about the famous word wrap kata? Robert C. Martin has posted a much cited solution including an extensive reasoning behind his TDD approach. So maybe you want to compare it to Flow Design. The function signature given is:string WordWrap(string text, int maxLineLength) {...} That´s not an Entry Point since we don´t see an application with an environment and users. Nevertheless it´s a function which is supposed to provide a certain functionality. The text passed in has to be reformatted. The input is a single line of arbitrary length consisting of words separated by spaces. The output should consist of one or more lines of a maximum length specified. If a word is longer than a the maximum line length it can be split in multiple parts each fitting in a line. Flow Design Let´s start by brainstorming the process to accomplish the feat of reformatting the text. What´s needed? Words need to be assembled into lines Words need to be extracted from the input text The resulting lines need to be assembled into the output text Words too long to fit in a line need to be split Does sound about right? I guess so. And it shows a kind of priority. Long words are a special case. So maybe there is a hint for an incremental design here. First let´s tackle “average words” (words not longer than a line). Here´s the Flow Design for this increment: The the first three bullet points turned into functional units with explicit data added. As the signature requires a text is transformed into another text. See the input of the first functional unit and the output of the last functional unit. In between no text flows, but words and lines. That´s good to see because thereby the domain is clearly represented in the design. The requirements are talking about words and lines and here they are. But note the asterisk! It´s not outside the brackets but inside. That means it´s not a stream of words or lines, but lists or sequences. For each text a sequence of words is output. For each sequence of words a sequence of lines is produced. The asterisk is used to abstract from the concrete implementation. Like with streams. Whether the list of words gets implemented as an array or an IEnumerable is not important during design. It´s an implementation detail. Does any processing step require further refinement? I don´t think so. They all look pretty “atomic” to me. And if not… I can always backtrack and refine a process step using functional design later once I´ve gained more insight into a sub-problem. Implementation The implementation is straightforward as you can imagine. The processing steps can all be translated into functions. Each can be tested easily and separately. Each has a focused responsibility. And the process flow becomes just a sequence of function calls: Easy to understand. It clearly states how word wrapping works - on a high level of abstraction. And it´s easy to evolve as you´ll see. Flow Design - Increment 2 So far only texts consisting of “average words” are wrapped correctly. Words not fitting in a line will result in lines too long. Wrapping long words is a feature of the requested functionality. Whether it´s there or not makes a difference to the user. To quickly get feedback I decided to first implement a solution without this feature. But now it´s time to add it to deliver the full scope. Fortunately Flow Design automatically leads to code following the Open Closed Principle (OCP). It´s easy to extend it - instead of changing well tested code. How´s that possible? Flow Design allows for extension of functionality by inserting functional units into the flow. That way existing functional units need not be changed. The data flow arrow between functional units is a natural extension point. No need to resort to the Strategy Pattern. No need to think ahead where extions might need to be made in the future. I just “phase in” the remaining processing step: Since neither Extract words nor Reformat know of their environment neither needs to be touched due to the “detour”. The new processing step accepts the output of the existing upstream step and produces data compatible with the existing downstream step. Implementation - Increment 2 A trivial implementation checking the assumption if this works does not do anything to split long words. The input is just passed on: Note how clean WordWrap() stays. The solution is easy to understand. A developer looking at this code sometime in the future, when a new feature needs to be build in, quickly sees how long words are dealt with. Compare this to Robert C. Martin´s solution:[4] How does this solution handle long words? Long words are not even part of the domain language present in the code. At least I need considerable time to understand the approach. Admittedly the Flow Design solution with the full implementation of long word splitting is longer than Robert C. Martin´s. At least it seems. Because his solution does not cover all the “word wrap situations” the Flow Design solution handles. Some lines would need to be added to be on par, I guess. But even then… Is a difference in LOC that important as long as it´s in the same ball park? I value understandability and openness for extension higher than saving on the last line of code. Simplicity is not just less code, it´s also clarity in design. But don´t take my word for it. Try Flow Design on larger problems and compare for yourself. What´s the easier, more straightforward way to clean code? And keep in mind: You ain´t seen all yet ;-) There´s more to Flow Design than described in this chapter. In closing I hope I was able to give you a impression of functional design that makes you hungry for more. To me it´s an inevitable step in software development. Jumping from requirements to code does not scale. And it leads to dirty code all to quickly. Some thought should be invested first. Where there is a clear Entry Point visible, it´s functionality should be designed using data flows. Because with data flows abstraction is possible. For more background on why that´s necessary read my blog article here. For now let me point out to you - if you haven´t already noticed - that Flow Design is a general purpose declarative language. It´s “programming by intention” (Shalloway et al.). Just write down how you think the solution should work on a high level of abstraction. This breaks down a large problem in smaller problems. And by following the PoMO the solutions to those smaller problems are independent of each other. So they are easy to test. Or you could even think about getting them implemented in parallel by different team members. Flow Design not only increases evolvability, but also helps becoming more productive. All team members can participate in functional design. This goes beyon collective code ownership. We´re talking collective design/architecture ownership. Because with Flow Design there is a common visual language to talk about functional design - which is the foundation for all other design activities.   PS: If you like what you read, consider getting my ebook “The Incremental Architekt´s Napkin”. It´s where I compile all the articles in this series for easier reading. I like the strictness of Function Programming - but I also find it quite hard to live by. And it certainly is not what millions of programmers are used to. Also to me it seems, the real world is full of state and side effects. So why give them such a bad image? That´s why functional design takes a more pragmatic approach. State and side effects are ok for processing steps - but be sure to follow the SRP. Don´t put too much of it into a single processing step. ? Image taken from www.physioweb.org ? My code samples are written in C#. C# sports typed function pointers called delegates. Action is such a function pointer type matching functions with signature void someName(T t). Other languages provide similar ways to work with functions as first class citizens - even Java now in version 8. I trust you find a way to map this detail of my translation to your favorite programming language. I know it works for Java, C++, Ruby, JavaScript, Python, Go. And if you´re using a Functional Programming language it´s of course a no brainer. ? Taken from his blog post “The Craftsman 62, The Dark Path”. ?

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• Windows Azure Use Case: Web Applications

  - by BuckWoody

  This is one in a series of posts on when and where to use a distributed architecture design in your organization's computing needs. You can find the main post here: http://blogs.msdn.com/b/buckwoody/archive/2011/01/18/windows-azure-and-sql-azure-use-cases.aspx  Description: Many applications have a requirement to be located outside of the organization’s internal infrastructure control. For instance, the company website for a brick-and-mortar retail company may want to post not only static but interactive content to be available to their external customers, and not want the customers to have access inside the organization’s firewall. There are also cases of pure web applications used for a great many of the internal functions of the business. This allows for remote workers, shared customer/employee workloads and data and other advantages. Some firms choose to host these web servers internally, others choose to contract out the infrastructure to an “ASP” (Application Service Provider) or an Infrastructure as a Service (IaaS) company. In any case, the design of these applications often resembles the following: In this design, a server (or perhaps more than one) hosts the presentation function (http or https) access to the application, and this same system may hold the computational aspects of the program. Authorization and Access is controlled programmatically, or is more open if this is a customer-facing application. Storage is either placed on the same or other servers, hosted within an RDBMS or NoSQL database, or a combination of the options, all coded into the application. High-Availability within this scenario is often the responsibility of the architects of the application, and by purchasing more hosting resources which must be built, licensed and configured, and manually added as demand requires, although some IaaS providers have a partially automatic method to add nodes for scale-out, if the architecture of the application supports it. Disaster Recovery is the responsibility of the system architect as well. Implementation: In a Windows Azure Platform as a Service (PaaS) environment, many of these architectural considerations are designed into the system. The Azure “Fabric” (not to be confused with the Azure implementation of Application Fabric - more on that in a moment) is designed to provide scalability. Compute resources can be added and removed programmatically based on any number of factors. Balancers at the request-level of the Fabric automatically route http and https requests. The fabric also provides High-Availability for storage and other components. Disaster recovery is a shared responsibility between the facilities (which have the ability to restore in case of catastrophic failure) and your code, which should build in recovery. In a Windows Azure-based web application, you have the ability to separate out the various functions and components. Presentation can be coded for multiple platforms like smart phones, tablets and PC’s, while the computation can be a single entity shared between them. This makes the applications more resilient and more object-oriented, and lends itself to a SOA or Distributed Computing architecture. It is true that you could code up a similar set of functionality in a traditional web-farm, but the difference here is that the components are built into the very design of the architecture. The API’s and DLL’s you call in a Windows Azure code base contains components as first-class citizens. For instance, if you need storage, it is simply called within the application as an object.  Computation has multiple options and the ability to scale linearly. You also gain another component that you would either have to write or bolt-in to a typical web-farm: the Application Fabric. This Windows Azure component provides communication between applications or even to on-premise systems. It provides authorization in either person-based or claims-based perspectives. SQL Azure provides relational storage as another option, and can also be used or accessed from on-premise systems. It should be noted that you can use all or some of these components individually. Resources: Design Strategies for Scalable Active Server Applications - http://msdn.microsoft.com/en-us/library/ms972349.aspx  Physical Tiers and Deployment  - http://msdn.microsoft.com/en-us/library/ee658120.aspx

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• Something about Property Management or &hellip; the understanding of SharePoint Admins/roles ?!?

  - by Enrique Lima

  When I talk about SharePoint, for some reason it comes to my mind as if it were property management and all the tasks associated with it. So, imagine you have a lot ( a piece of land of sorts), you then decide there is something you want to do with it.  So, you make the choice of having a building built.  Now, in order to go forward with your plan, you need to check what the rules/regulations are.  Has is it been zoned residential, commercial, industrial … you get the idea.  This to me sounds like Governance.  The what am I to do given a defined set of rules. We keep on moving forward based on those rules.  And with this we start the process of building, the building process takes us to survey the land, identify what our boundaries are.  And as we go along we start getting the idea in our head as to what we will do as far as the building goes.  We identify the essentials of the building, basic services and such.  All in all, we plan.  And as with many things we do, we like solid foundations.  What a solid foundation looks like will depend on where and what we build.  The way buildings are built depends in many ways in being able to foresee the potential for natural disasters or to try to leverage the lay of the land.  Sound familiar?  We have done our Requirements Gathering. We have the building in place, we have followed the zoning rules, we have implemented services.  But we need someone to manage the building, now we move on to the human side of the story.  We want to establish a means to normalcy in the building, someone that can be the monitoring agent as to the “what’s going on?” of it.  This person will be tasked with making sure all basic services are functional, that measures are taken if there is an issue and so on.  Enter the Farm Administrator. In a way, we establish an extension of the rules to make sure the building and the apartments/offices build follow a standard set of rules too. Now, in turn you will have people leasing or buying the apartments/offices, they will be the keepers of that space.  So, now we are building sites, we have moved from having the building (farm) ready, to leasing/selling offices/apartments (site collections).  There will be someone assuming responsibility for those offices, that person will authorize or be informed about activities and also who not only gets a code into the building, but perhaps a key to the office.  Enter Site Collection Administrator.  And then perhaps we move on to the person that would be responsible for specifics within the office, for example a Human Resources Manager or Coordinator.  They will have specific control and knowledge about people.  A facilities coordinator, and so on.  I would translate that into Site Administrators. With that said then, we identify the following: Role Name Responsibility (but not limited to) Farm Administrator Infrastructure Site Collection Admin Policies for Content, Hierarchy, Recycle Bin, Security and Access Site Owner (Site Admin) Security and Access, Training, Guidance, Manage Templates All in all there are different levels of responsibility to be handled, but it is very important to understand what they are and what they mean. Here is a link to very well laid out explanation on this … http://www.endusersharepoint.com/2009/08/11/site-managers-and-end-user-expectations-roles-and-responsibilities/

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• Investigating Strategies For Functional Decomposition

  - by Liam McLennan

  Introducing Functional Decomposition Before I begin I must apologise. I think I am using the term ‘functional decomposition’ loosely, and probably incorrectly. For the purpose of this article I use functional decomposition to mean the recursive splitting of a large problem into increasingly smaller ones, so that the one large problem may be solved by solving a set of smaller problems. The justification for functional decomposition is that the decomposed problem is more easily solved. As software developers we recognise that the smaller pieces are more easily tested, since they do less and are more cohesive. Functional decomposition is important to all scientific pursuits. Once we understand natural selection we can start to look for humanities ancestral species, once we understand the big bang we can trace our expanding universe back to its origin. Isaac Newton acknowledged the compositional nature of his scientific achievements: If I have seen further than others, it is by standing upon the shoulders of giants   The Two Strategies For Functional Decomposition of Computer Programs Private Methods When I was working on my undergraduate degree I was taught to functionally decompose problems by using private methods. Consider the problem of painting a house. The obvious solution is to solve the problem as a single unit: public void PaintAHouse() { // all the things required to paint a house ... } We decompose the problem by breaking it into parts: public void PaintAHouse() { PaintUndercoat(); PaintTopcoat(); } private void PaintUndercoat() { // everything required to paint the undercoat } private void PaintTopcoat() { // everything required to paint the topcoat } The problem can be recursively decomposed until a sufficiently granular level of detail is reached: public void PaintAHouse() { PaintUndercoat(); PaintTopcoat(); } private void PaintUndercoat() { prepareSurface(); fetchUndercoat(); paintUndercoat(); } private void PaintTopcoat() { fetchPaint(); paintTopcoat(); } According to Wikipedia, at least one computer programmer has referred to this process as “the art of subroutining”. The practical issues that I have encountered when using private methods for decomposition are: To preserve the top level API all of the steps must be private. This means that they can’t easily be tested. The private methods often have little cohesion except that they form part of the same solution. Decomposing to Classes The alternative is to decompose large problems into multiple classes, effectively using a class instead of each private method. The API delegates to related classes, so the API is not polluted by the sub-steps of the problem, and the steps can be easily tested because they are each in their own highly cohesive class. Additionally, I think that this technique facilitates better adherence to the Single Responsibility Principle, since each class can be decomposed until it has precisely one responsibility. Revisiting my previous example using class composition: public class HousePainter { private undercoatPainter = new UndercoatPainter(); private topcoatPainter = new TopcoatPainter(); public void PaintAHouse() { undercoatPainter.Paint(); topcoatPainter.Paint(); } } Summary When decomposing a problem there is more than one way to represent the sub-problems. Using private methods keeps the logic in one place and prevents a proliferation of classes (thereby following the four rules of simple design) but the class decomposition is more easily testable and more compatible with the Single Responsibility Principle.

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• add a decorate function to a class

  - by wiso

  I have a decorated function (simplified version): class Memoize: def __init__(self, function): self.function = function self.memoized = {} def __call__(self, *args, **kwds): hash = args try: return self.memoized[hash] except KeyError: self.memoized[hash] = self.function(*args) return self.memoized[hash] @Memoize def _DrawPlot(self, options): do something... now I want to add this method to a pre-esisting class. ROOT.TChain.DrawPlot = _DrawPlot when I call this method: chain = TChain() chain.DrawPlot(opts) I got: self.memoized[hash] = self.function(*args) TypeError: _DrawPlot() takes exactly 2 arguments (1 given) why doesn't it propagate self?

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• prolog sets problem, stack overflow

  - by garm0nboz1a

  Hi. I'm gonna show some code and ask, what could be optimized and where am I sucked? sublist([], []). sublist([H | Tail1], [H | Tail2]) :- sublist(Tail1, Tail2). sublist(H, [_ | Tail]) :- sublist(H, Tail). less(X, X, _). less(X, Z, RelationList) :- member([X,Z], RelationList). less(X, Z, RelationList) :- member([X,Y], RelationList), less(Y, Z, RelationList), \+less(Z, X, RelationList). lessList(X, LessList, RelationList) :- findall(Y, less(X, Y, RelationList), List), list_to_set(List, L), sort(L, LessList), !. list_mltpl(List1, List2, List) :- findall(X, ( member(X, List1), member(X, List2)), List). chain([_], _). chain([H,T | Tail], RelationList) :- less(H, T, RelationList), chain([T|Tail], RelationList), !. have_inf(X1, X2, RelationList) :- lessList(X1, X1_cone, RelationList), lessList(X2, X2_cone, RelationList), list_mltpl(X1_cone, X2_cone, Cone), chain(Cone, RelationList), !. relations(List, E) :- findall([X1,X2], (member(X1, E), member(X2, E), X1 =\= X2), Relations), sublist(List, Relations). semilattice(List, E) :- forall( (member(X1, E), member(X2, E), X1 < X2), have_inf(X1, X2, List) ). main(E) :- relations(X, E), semilattice(X, E). I'm trying to model all possible graph sets of N elements. Predicate relations(List, E) connects list of possible graphs(List) and input set E. Then I'm describing semilattice predicate to check relations' List for some properties. So, what I have. 1) semilattice/2 is working fast and clear ?- semilattice([[1,3],[2,4],[3,5],[4,5]],[1,2,3,4,5]). true. ?- semilattice([[1,3],[1,4],[2,3],[2,4],[3,5],[4,5]],[1,2,3,4,5]). false. 2) relations/2 is working not well ?- findall(X, relations(X,[1,2,3,4]), List), length(List, Len), writeln(Len),fail. 4096 false. ?- findall(X, relations(X,[1,2,3,4,5]), List), length(List, Len), writeln(Len),fail. ERROR: Out of global stack ^ Exception: (11) setup_call_catcher_cleanup('$bags':'$new_findall_bag'(17852886), '$bags':fa_loop(_G263, user:relations(_G263, [1, 2, 3, 4|...]), 17852886, _G268, []), _G835, '$bags':'$destroy_findall_bag'(17852886)) ? abort % Execution Aborted 3) Mix of them to finding all possible semilattice does not work at all. ?- main([1,2]). ERROR: Out of local stack ^ Exception: (15) setup_call_catcher_cleanup('$bags':'$new_findall_bag'(17852886), '$bags':fa_loop(_G41, user:less(1, _G41, [[1, 2], [2, 1]]), 17852886, _G52, []), _G4767764, '$bags':'$destroy_findall_bag'(17852886)) ?

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• Design patterns for Caching Images in a MVC?

  - by Onema

  Hi, I'm designing an image cache system that will be used in an MVC CMS. The main purpose of the image cacher is to modify images: scale, crop, etc and cache them in the client site. I have created an image cache Model and Mapper that interact with the Database, to keep track of the images and know what kind of actions have been applied to them (scale, crop, etc). In addition to the Model and Mapper I have created a ImageCacher Class that is used by the API to manage the Model and image creation based on arguments passed by the client site, this class creates the images and generates the links to the images for the View. A coworker argued that I need to include the functionality of this last Class inside the Model, as the bulk of the logic should go in the model. I respectfully disagree with him since I feel the model's responsibility is to deal with the information about the images cached at the database level, and the responsibility of the ImageCacher Class is to create the url/image that we will be caching (keeping the single responsibility principle). In addition to this I believe that a model should not have Presentation-related features, like creating or showing images. Does anyone have any insight on this? is there a particular design pattern that would make this division of tasks clear and and the image cacher reusable? Should I add all the logic in the Model? Thank you.

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• NFS Mounts Issues

  - by user554005

  Having some issue with a NFS Setup on the clients it just times out refuses to connect [root@host9 ~]# mount 192.168.0.17:/home/export /mnt/export mount: mount to NFS server '192.168.0.17' failed: timed out (retrying). mount: mount to NFS server '192.168.0.17' failed: timed out (retrying). mount: mount to NFS server '192.168.0.17' failed: timed out (retrying). mount: mount to NFS server '192.168.0.17' failed: timed out (retrying). Here are the settings I'm using: [root@host17 /home/export]# cat /etc/hosts.allow # # hosts.allow This file contains access rules which are used to # allow or deny connections to network services that # either use the tcp_wrappers library or that have been # started through a tcp_wrappers-enabled xinetd. # # See 'man 5 hosts_options' and 'man 5 hosts_access' # for information on rule syntax. # See 'man tcpd' for information on tcp_wrappers # portmap: 192.168.0.0/255.255.255.0 lockd: 192.168.0.0/255.255.255.0 rquotad: 192.168.0.0/255.255.255.0 mountd: 192.168.0.0/255.255.255.0 statd: 192.168.0.0/255.255.255.0 [root@host17 /home/export]# cat /etc/hosts.deny # # hosts.deny This file contains access rules which are used to # deny connections to network services that either use # the tcp_wrappers library or that have been # started through a tcp_wrappers-enabled xinetd. # # The rules in this file can also be set up in # /etc/hosts.allow with a 'deny' option instead. # # See 'man 5 hosts_options' and 'man 5 hosts_access' # for information on rule syntax. # See 'man tcpd' for information on tcp_wrappers # portmap:ALL lockd:ALL mountd:ALL rquotad:ALL statd:ALL [root@host17 /home/export]# cat /etc/exports /home/export 192.168.0.0/255.255.255.0(rw) [root@host17 /home/export]# iptables -L Chain INPUT (policy ACCEPT) target prot opt source destination RH-Firewall-1-INPUT all -- anywhere anywhere Chain FORWARD (policy ACCEPT) target prot opt source destination RH-Firewall-1-INPUT all -- anywhere anywhere Chain OUTPUT (policy ACCEPT) target prot opt source destination Chain RH-Firewall-1-INPUT (2 references) target prot opt source destination ACCEPT all -- anywhere anywhere ACCEPT icmp -- anywhere anywhere icmp any ACCEPT esp -- anywhere anywhere ACCEPT ah -- anywhere anywhere ACCEPT udp -- anywhere 224.0.0.251 udp dpt:mdns ACCEPT udp -- anywhere anywhere udp dpt:ipp ACCEPT tcp -- anywhere anywhere tcp dpt:ipp ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:ssh ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:http ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:https ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:6379 ACCEPT udp -- 192.168.0.0/24 anywhere state NEW udp dpt:sunrpc ACCEPT tcp -- 192.168.0.0/24 anywhere state NEW tcp dpt:sunrpc ACCEPT tcp -- 192.168.0.0/24 anywhere state NEW tcp dpt:nfs ACCEPT tcp -- 192.168.0.0/24 anywhere state NEW tcp dpt:32803 ACCEPT udp -- 192.168.0.0/24 anywhere state NEW udp dpt:filenet-rpc ACCEPT tcp -- 192.168.0.0/24 anywhere state NEW tcp dpt:892 ACCEPT udp -- 192.168.0.0/24 anywhere state NEW udp dpt:892 ACCEPT tcp -- 192.168.0.0/24 anywhere state NEW tcp dpt:rquotad ACCEPT udp -- 192.168.0.0/24 anywhere state NEW udp dpt:rquotad ACCEPT tcp -- 192.168.0.0/24 anywhere state NEW tcp dpt:pftp ACCEPT udp -- 192.168.0.0/24 anywhere state NEW udp dpt:pftp REJECT all -- anywhere anywhere reject-with icmp-host-prohibited on the clients here is some rpcinfos [root@host9 ~]# rpcinfo -p 192.168.0.17 program vers proto port 100000 4 tcp 111 portmapper 100000 3 tcp 111 portmapper 100000 2 tcp 111 portmapper 100000 4 udp 111 portmapper 100000 3 udp 111 portmapper 100000 2 udp 111 portmapper 100011 1 udp 875 rquotad 100011 2 udp 875 rquotad 100011 1 tcp 875 rquotad 100011 2 tcp 875 rquotad 100005 1 udp 45857 mountd 100005 1 tcp 55772 mountd 100005 2 udp 34021 mountd 100005 2 tcp 59542 mountd 100005 3 udp 60930 mountd 100005 3 tcp 53086 mountd 100003 2 udp 2049 nfs 100003 3 udp 2049 nfs 100003 4 udp 2049 nfs 100227 2 udp 2049 nfs_acl 100227 3 udp 2049 nfs_acl 100003 2 tcp 2049 nfs 100003 3 tcp 2049 nfs 100003 4 tcp 2049 nfs 100227 2 tcp 2049 nfs_acl 100227 3 tcp 2049 nfs_acl 100021 1 udp 59832 nlockmgr 100021 3 udp 59832 nlockmgr 100021 4 udp 59832 nlockmgr 100021 1 tcp 36140 nlockmgr 100021 3 tcp 36140 nlockmgr 100021 4 tcp 36140 nlockmgr 100024 1 udp 46494 status 100024 1 tcp 49672 status [root@host9 ~]# [root@host9 ~]# rpcinfo -u 192.168.0.17 nfs rpcinfo: RPC: Timed out program 100003 version 0 is not available [root@host9 ~]# rpcinfo -u 192.168.0.17 portmap program 100000 version 2 ready and waiting program 100000 version 3 ready and waiting program 100000 version 4 ready and waiting [root@host9 ~]# rpcinfo -u 192.168.0.17 mount rpcinfo: RPC: Timed out program 100005 version 0 is not available [root@host9 ~]# I'm running CentOS 5.8 on all systems

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• Cannot connect to MySQL Server on RHEL 5.7

  - by Jeffrey Wong

  I have a standard MySQL Server running on Red hat 5.7. I have edited /etc/my.cnf to specify the bind address as my server's public IP address. [mysqld] datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock user=mysql # Default to using old password format for compatibility with mysql 3.x # clients (those using the mysqlclient10 compatibility package). old_passwords=1 # Disabling symbolic-links is recommended to prevent assorted security risks ; # to do so, uncomment this line: # symbolic-links=0 [mysqld_safe] log-error=/var/log/mysqld.log pid-file=/var/run/mysqld/mysqld.pid bind-address=171.67.88.25 port=3306 And I have also restarted my firewall sudo /sbin/iptables -A INPUT -i eth0 -p tcp --destination-port 3306 -j ACCEPT /sbin/service iptables save The network administrator has already opened port 3306 for this box. When connecting from a remote computer (running Ubuntu 10.10, server is running RHEL 5.7), I issue mysql -u jeffrey -p --host=171.67.88.25 --port=3306 --socket=/var/lib/mysql/mysql.sock but receive a ERROR 2003 (HY000): Can't connect to MySQL server on '171.67.88.25' (113). I've noticed that the socket file /var/lib/mysql/mysql.sock is blank. Should this be the case? UPDATE The result of netstat -an | grep 3306 tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN Result of sudo netstat -tulpen Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State User Inode PID/Program name tcp 0 0 127.0.0.1:2208 0.0.0.0:* LISTEN 0 7602 3168/hpiod tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 27 7827 3298/mysqld tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 0 5110 2802/portmap tcp 0 0 0.0.0.0:8787 0.0.0.0:* LISTEN 0 8431 3326/rserver tcp 0 0 0.0.0.0:915 0.0.0.0:* LISTEN 0 5312 2853/rpc.statd tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 0 7655 3188/sshd tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 0 7688 3199/cupsd tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 0 8025 3362/sendmail: acce tcp 0 0 127.0.0.1:2207 0.0.0.0:* LISTEN 0 7620 3173/python udp 0 0 0.0.0.0:909 0.0.0.0:* 0 5300 2853/rpc.statd udp 0 0 0.0.0.0:912 0.0.0.0:* 0 5309 2853/rpc.statd udp 0 0 0.0.0.0:68 0.0.0.0:* 0 4800 2598/dhclient udp 0 0 0.0.0.0:36177 0.0.0.0:* 70 8314 3476/avahi-daemon: udp 0 0 0.0.0.0:5353 0.0.0.0:* 70 8313 3476/avahi-daemon: udp 0 0 0.0.0.0:111 0.0.0.0:* 0 5109 2802/portmap udp 0 0 0.0.0.0:631 0.0.0.0:* 0 7691 3199/cupsd Result of sudo /sbin/iptables -L -v -n Chain INPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 6373 2110K RH-Firewall-1-INPUT all -- * * 0.0.0.0/0 0.0.0.0/0 Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 0 0 RH-Firewall-1-INPUT all -- * * 0.0.0.0/0 0.0.0.0/0 Chain OUTPUT (policy ACCEPT 1241 packets, 932K bytes) pkts bytes target prot opt in out source destination Chain RH-Firewall-1-INPUT (2 references) pkts bytes target prot opt in out source destination 572 861K ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/0 1 28 ACCEPT icmp -- * * 0.0.0.0/0 0.0.0.0/0 icmp type 255 0 0 ACCEPT esp -- * * 0.0.0.0/0 0.0.0.0/0 0 0 ACCEPT ah -- * * 0.0.0.0/0 0.0.0.0/0 46 6457 ACCEPT udp -- * * 0.0.0.0/0 224.0.0.251 udp dpt:5353 0 0 ACCEPT udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:631 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:631 782 157K ACCEPT all -- * * 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED 2 120 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:22 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:443 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:23 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:80 4970 1086K REJECT all -- * * 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibited Result of nmap -P0 -p3306 171.67.88.25 Host is up (0.027s latency). PORT STATE SERVICE 3306/tcp filtered mysql Nmap done: 1 IP address (1 host up) scanned in 0.09 seconds Solution When everything else fails, go GUI! system-config-securitylevel and add port 3306. All done!

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• SQL SERVER – How to Recover SQL Database Data Deleted by Accident

  - by Pinal Dave

  In Repair a SQL Server database using a transaction log explorer, I showed how to use ApexSQL Log, a SQL Server transaction log viewer, to recover a SQL Server database after a disaster. In this blog, I’ll show you how to use another SQL Server disaster recovery tool from ApexSQL in a situation when data is accidentally deleted. You can download ApexSQL Recover here, install, and play along. With a good SQL Server disaster recovery strategy, data recovery is not a problem. You have a reliable full database backup with valid data, a full database backup and subsequent differential database backups, or a full database backup and a chain of transaction log backups. But not all situations are ideal. Here we’ll address some sub-optimal scenarios, where you can still successfully recover data. If you have only a full database backup This is the least optimal SQL Server disaster recovery strategy, as it doesn’t ensure minimal data loss. For example, data was deleted on Wednesday. Your last full database backup was created on Sunday, three days before the records were deleted. By using the full database backup created on Sunday, you will be able to recover SQL database records that existed in the table on Sunday. If there were any records inserted into the table on Monday or Tuesday, they will be lost forever. The same goes for records modified in this period. This method will not bring back modified records, only the old records that existed on Sunday. If you restore this full database backup, all your changes (intentional and accidental) will be lost and the database will be reverted to the state it had on Sunday. What you have to do is compare the records that were in the table on Sunday to the records on Wednesday, create a synchronization script, and execute it against the Wednesday database. If you have a full database backup followed by differential database backups Let’s say the situation is the same as in the example above, only you create a differential database backup every night. Use the full database backup created on Sunday, and the last differential database backup (created on Tuesday). In this scenario, you will lose only the data inserted and updated after the differential backup created on Tuesday. If you have a full database backup and a chain of transaction log backups This is the SQL Server disaster recovery strategy that provides minimal data loss. With a full chain of transaction logs, you can recover the SQL database to an exact point in time. To provide optimal results, you have to know exactly when the records were deleted, because restoring to a later point will not bring back the records. This method requires restoring the full database backup first. If you have any differential log backup created after the last full database backup, restore the most recent one. Then, restore transaction log backups, one by one, it the order they were created starting with the first created after the restored differential database backup. Now, the table will be in the state before the records were deleted. You have to identify the deleted records, script them and run the script against the original database. Although this method is reliable, it is time-consuming and requires a lot of space on disk. How to easily recover deleted records? The following solution enables you to recover SQL database records even if you have no full or differential database backups and no transaction log backups. To understand how ApexSQL Recover works, I’ll explain what happens when table data is deleted. Table data is stored in data pages. When you delete table records, they are not immediately deleted from the data pages, but marked to be overwritten by new records. Such records are not shown as existing anymore, but ApexSQL Recover can read them and create undo script for them. How long will deleted records stay in the MDF file? It depends on many factors, as time passes it’s less likely that the records will not be overwritten. The more transactions occur after the deletion, the more chances the records will be overwritten and permanently lost. Therefore, it’s recommended to create a copy of the database MDF and LDF files immediately (if you cannot take your database offline until the issue is solved) and run ApexSQL Recover on them. Note that a full database backup will not help here, as the records marked for overwriting are not included in the backup. First, I’ll delete some records from the Person.EmailAddress table in the AdventureWorks database.   I can delete these records in SQL Server Management Studio, or execute a script such as DELETE FROM Person.EmailAddress WHERE BusinessEntityID BETWEEN 70 AND 80 Then, I’ll start ApexSQL Recover and select From DELETE operation in the Recovery tab.   In the Select the database to recover step, first select the SQL Server instance. If it’s not shown in the drop-down list, click the Server icon right to the Server drop-down list and browse for the SQL Server instance, or type the instance name manually. Specify the authentication type and select the database in the Database drop-down list.   In the next step, you’re prompted to add additional data sources. As this can be a tricky step, especially for new users, ApexSQL Recover offers help via the Help me decide option.   The Help me decide option guides you through a series of questions about the database transaction log and advises what files to add. If you know that you have no transaction log backups or detached transaction logs, or the online transaction log file has been truncated after the data was deleted, select No additional transaction logs are available. If you know that you have transaction log backups that contain the delete transactions you want to recover, click Add transaction logs. The online transaction log is listed and selected automatically.   Click Add if to add transaction log backups. It would be best if you have a full transaction log chain, as explained above. The next step for this option is to specify the time range.   Selecting a small time range for the time of deletion will create the recovery script just for the accidentally deleted records. A wide time range might script the records deleted on purpose, and you don’t want that. If needed, you can check the script generated and manually remove such records. After that, for all data sources options, the next step is to select the tables. Be careful here, if you deleted some data from other tables on purpose, and don’t want to recover them, don’t select all tables, as ApexSQL Recover will create the INSERT script for them too.   The next step offers two options: to create a recovery script that will insert the deleted records back into the Person.EmailAddress table, or to create a new database, create the Person.EmailAddress table in it, and insert the deleted records. I’ll select the first one.   The recovery process is completed and 11 records are found and scripted, as expected.   To see the script, click View script. ApexSQL Recover has its own script editor, where you can review, modify, and execute the recovery script. The insert into statements look like: INSERT INTO Person.EmailAddress( BusinessEntityID, EmailAddressID, EmailAddress, rowguid, ModifiedDate) VALUES( 70, 70, N'[email protected]' COLLATE SQL_Latin1_General_CP1_CI_AS, 'd62c5b4e-c91f-403f-b630-7b7e0fda70ce', '20030109 00:00:00.000' ); To execute the script, click Execute in the menu.   If you want to check whether the records are really back, execute SELECT * FROM Person.EmailAddress WHERE BusinessEntityID BETWEEN 70 AND 80 As shown, ApexSQL Recover recovers SQL database data after accidental deletes even without the database backup that contains the deleted data and relevant transaction log backups. ApexSQL Recover reads the deleted data from the database data file, so this method can be used even for databases in the Simple recovery model. Besides recovering SQL database records from a DELETE statement, ApexSQL Recover can help when the records are lost due to a DROP TABLE, or TRUNCATE statement, as well as repair a corrupted MDF file that cannot be attached to as SQL Server instance. You can find more information about how to recover SQL database lost data and repair a SQL Server database on ApexSQL Solution center. There are solutions for various situations when data needs to be recovered. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Backup and Restore, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• How can I block a specific type of DDoS attack?

  - by Mark

  My site is being attacked and is using up all the RAM. I looked at the Apache logs and every malicious hit seems to simply be a POST request on /, which is never required by a normal user. So I thought and wondered if there's any sort of solution or utility that will monitor my Apache logs and block every IP that performs a POST request on the site root. I'm not familiar with DDoS protection and searching didn't seem to give me an answer, so I came here. Thanks. Example logs: 103.3.221.202 - - [30/Sep/2012:16:02:03 +0000] "POST / HTTP/1.1" 302 485 "-" "Mozilla/5.0 (iPad; CPU OS 5_1_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B206 Safari/7534.48.3" 122.72.80.100 - - [30/Sep/2012:16:02:03 +0000] "POST / HTTP/1.1" 302 485 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_4) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.47 Safari/536.11" 122.72.28.15 - - [30/Sep/2012:16:02:04 +0000] "POST / HTTP/1.1" 302 485 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727)" 210.75.120.5 - - [30/Sep/2012:16:02:04 +0000] "POST / HTTP/1.1" 302 485 "-" "Mozilla/5.0 (Windows NT 6.1; rv:12.0) Gecko/20100101 Firefox/12.0" 122.96.59.103 - - [30/Sep/2012:16:02:04 +0000] "POST / HTTP/1.1" 302 485 "-" "Mozilla/5.0 (Linux; U; Android 2.2; fr-fr; Desire_A8181 Build/FRF91) App3leWebKit/53.1 (KHTML, like Gecko) Version/4.0 Mobile Safari/533.1" 122.96.59.103 - - [30/Sep/2012:16:02:04 +0000] "POST / HTTP/1.1" 302 485 "-" "Mozilla/5.0 (Linux; U; Android 2.2; fr-fr; Desire_A8181 Build/FRF91) App3leWebKit/53.1 (KHTML, like Gecko) Version/4.0 Mobile Safari/533.1" 122.72.124.3 - - [30/Sep/2012:16:02:04 +0000] "POST / HTTP/1.1" 302 485 "-" "Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:13.0) Gecko/20100101 Firefox/13.0.1" 122.72.112.148 - - [30/Sep/2012:16:02:04 +0000] "POST / HTTP/1.1" 302 485 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:13.0) Gecko/20100101 Firefox/13.0.1" 190.39.210.26 - - [30/Sep/2012:16:02:04 +0000] "POST / HTTP/1.0" 302 485 "-" "Mozilla/5.0 (Windows NT 6.0; rv:13.0) Gecko/20100101 Firefox/13.0.1" 210.213.245.230 - - [30/Sep/2012:16:02:04 +0000] "POST / HTTP/1.0" 302 485 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727)" 101.44.1.25 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (iPhone; CPU iPhone OS 5_1_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B206 Safari/7534.48.3" 101.44.1.28 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20100101 Firefox/13.0.1" 101.44.1.28 - - [30/Sep/2012:16:02:14 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20100101 Firefox/13.0.1" 103.3.221.202 - - [30/Sep/2012:16:02:13 +0000] "POST / HTTP/1.1" 302 466 "-" "Mozilla/5.0 (iPad; CPU OS 5_1_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B206 Safari/7534.48.3" 211.161.152.104 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)" 101.44.1.25 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.47 Safari/536.11" 101.44.1.25 - - [30/Sep/2012:16:02:11 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.47 Safari/536.11" 211.161.152.105 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2) Gecko/20100115 Firefox/3.6" 211.161.152.105 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; MRA 5.8 (build 4157); .NET CLR 2.0.50727; AskTbPTV/5.11.3.15590)" 211.161.152.105 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; MRA 5.8 (build 4157); .NET CLR 2.0.50727; AskTbPTV/5.11.3.15590)" 101.44.1.25 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.47 Safari/536.11" 101.44.1.25 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (iPhone; CPU iPhone OS 5_1_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B206 Safari/7534.48.3" 211.161.152.108 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (iPad; CPU OS 5_1_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B206 Safari/7534.48.3" 101.44.1.28 - - [30/Sep/2012:16:02:13 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20100101 Firefox/13.0.1" 211.161.152.106 - - [30/Sep/2012:16:02:11 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1; rv:5.0.1) Gecko/20100101 Firefox/5.0.1" 103.3.221.202 - - [30/Sep/2012:16:02:13 +0000] "POST / HTTP/1.1" 302 466 "-" "Mozilla/5.0 (iPad; CPU OS 5_1_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B206 Safari/7534.48.3" 101.44.1.28 - - [30/Sep/2012:16:02:11 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20100101 Firefox/13.0.1" 211.161.152.105 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; MRA 5.8 (build 4157); .NET CLR 2.0.50727; AskTbPTV/5.11.3.15590)" 211.161.152.104 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)" 211.161.152.104 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)" 211.161.152.105 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2) Gecko/20100115 Firefox/3.6" 101.44.1.25 - - [30/Sep/2012:16:02:10 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.47 Safari/536.11" 122.72.124.2 - - [30/Sep/2012:16:02:17 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20100101 Firefox/13.0.1" 122.72.124.2 - - [30/Sep/2012:16:02:11 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20100101 Firefox/13.0.1" 122.72.124.2 - - [30/Sep/2012:16:02:17 +0000] "POST / HTTP/1.1" 302 522 "-" "Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20100101 Firefox/13.0.1" 210.213.245.230 - - [30/Sep/2012:16:02:12 +0000] "POST / HTTP/1.0" 302 522 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727)" iptables -L: Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination - bui@debian:~$ sudo iptables -I INPUT 1 -m string --algo bm --string 'Keep-Alive: 300' -j DROP iptables: No chain/target/match by that name. bui@debian:~$ sudo iptables -A INPUT -m string --algo bm --string 'Keep-Alive: 300' -j DROP iptables: No chain/target/match by that name.

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• Get to Know a Candidate (6 of 25): Jill Stein&ndash;Green Party

  - by Brian Lanham

  DISCLAIMER: This is not a post about “Romney” or “Obama”. This is not a post for whom I am voting. Information sourced for Wikipedia. Stein is a physician with degrees from Harvard College and Harvard Medical School.  She serves on the boards of Greater Boston Physicians for Social Responsibility and MassVoters for Fair Elections, and has been active with the Massachusetts Coalition for Healthy Communities Jill Stein advocates a "Green New Deal" in which renewable energy jobs would be created to address climate change and environmental issues with the objective of employing "every American willing and able to work". Citing the research of Dr. Phillip Harvey, Professor of Law & Economics at Rutgers University, as evidence of the successful economic effects of the 1930s' New Deal projects, Stein would fund the plan with a 30% reduction in the U.S. military budget, returning US troops home, and increasing taxes on areas such as capital gains, offshore tax havens and multimillion dollar real estate. Stein plans on impacting what she sees as a growing convergence of environmental crises in water, soil, fisheries and forests, through the creation of sustainable infrastructure based in clean renewable energy generation and sustainable communities principles such as increasing intra-city mass transit and inter-city railroads, creating 'complete streets' that safely encourage bike and pedestrian traffic and regional food systems based on sustainable organic agriculture The Green Party of the United States was founded in 1991 as a voluntary association of state green parties. With its founding, the Green Party of the United States became the primary national Green organization in the United States, eclipsing the Greens/Green Party USA, which emphasized non-electoral movement building. The Green Party of the United States of America emphasizes environmentalism, non-hierarchical participatory democracy, social justice, respect for diversity, peace and nonviolence. Their "Ten Key Values," which are described as non-authoritative guiding principles, are as follows: Grassroots democracy Social justice and equal opportunity Ecological wisdom Nonviolence Decentralization Community-based economics Feminism and gender equality Respect for diversity Personal and global responsibility Future focus and sustainability The Green Party does not accept donations from corporations. Thus, the party's platforms and rhetoric critique any corporate influence and control over government, media, and American society at large. Stein has access to 403 electoral votes and is a write-in candidate in GA, IN, and MS Learn more about Jill Stein and Green Party on Wikipedia.

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• Attributes of an Ethical Programmer?

  - by ahmed

  Software that we write has ramifications in the real world. If not, it wouldn't be very useful. Thus, it has the potential to sweep across the world faster than a deadly manmade virus or to affect society every bit as much as genetic manipulation. Maybe we can't see how right now, but in the future our code will have ever-greater potential for harm or good. Of course, there's the issue of hacking. That's clearly a crime. Or is it that clear? Isn't hacking acceptable for our government in the event of national security? What about for other governments? Cases of life-and-death emergency? Tracking down deadbeat parents? Screening the genetic profile of job candidates? Where is the line drawn? Who decides? Do programmers have responsibility for how their code is used? What if a programmer writes code to pry into confidential information or copy-protected material? Does he bear responsibility along with the person who used the program? What about a programmer who knowingly or unknowingly writes code to "fix the books?" Should he be liable?

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• When module calling gets ugly

  - by Pete

  Has this ever happened to you? You've got a suite of well designed, single-responsibility modules, covered by unit tests. In any higher-level function you code, you are (95% of the code) simply taking output from one module and passing it as input to the next. Then, you notice this higher-level function has turned into a 100+ line script with multiple responsibilities. Here is the problem. It is difficult (impossible) to test that script. At least, it seems so. Do you agree? In my current project, all of the bugs came from this script. Further detail: each script represents a unique solution, or algorithm, formed by using different modules in different ways. Question: how can you remedy this situation? Knee-jerk answer: break the script up into single-responsibility modules. Comment on knee-jerk answer: it already is! Best answer I can come up with so far: create higher-level connector objects which "wire" modules together in particular ways (take output from one module, feed it as input to another module). Thus if our script was: FooInput fooIn = new FooInput(1, 2); FooOutput fooOutput = fooModule(fooIn); Double runtimevalue = getsomething(fooOutput.whatever); BarInput barIn = new BarInput( runtimevalue, fooOutput.someOtherValue); BarOutput barOut = barModule(BarIn); It would become with a connector: FooBarConnectionAlgo fooBarConnector = new fooBarConnector(fooModule, barModule); FooInput fooIn = new FooInput(1, 2); BarOutput barOut = fooBarConnector(fooIn); So the advantage is, besides hiding some code and making things clearer, we can test FooBarConnectionAlgo. I'm sure this situation comes up a lot. What do you do?

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• Enable Diagnostics in Oracle apps

  - by PRajkumar

  How to enable Oracle apps Diagnostics-> Examine, for certain users?   Steps 1 Navigate to System Administrator responsibility> Profile> System>     Steps 2 Enter profile name: Utilities:Diagnostics Enter Application User for whom you want to enable Diagnostics-> Examine   Steps 3 Give Yes at User level and Save the Changes Note – You can set Yes at Site level also if you want to enable this option for all Oracle application users   Steps 4 Again navigate to System Administrator responsibility> Profile> System> Enter profile name: Hide Diagnostics menu entry Enter Application User for whom you do not want to hide Diagnostics menu entry   Steps 5 Give No at User level and Save the Changes Note – You can set No at Site level also if you do not want to hide menu entry option for all Oracle application users Steps 6 Congratulations you have successfully enabled Diagnostics-> Examine Logout from Oracle Application and login again. Now can see Diagnostics-> Examine option

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• how to deal with controller mutations

  - by Milovan Zogovic

  During development process, things are constantly changing (especially in early phases). Requirements change, UI changes, everything changes. Pages that clearly belonged to specific controller, mutated to something completely different in the future. For example. Lets say that we have website for managing Projects. One page of the website was dedicated to managing existing, and inviting new members of specific project. Naturally, I created members controller nested under projects which had proper responsibility. Later in the development, it turned out that it was the only page that was "configuring the project" in some way, so additional functionalities were added to it: editing project description setting project as a default ... In other words, this page changed its primary responsibility from managing project members to managing project itself. Ideally, this page should be moved to "edit" action of "projects" controller. That would mean that all request and controller specs need to refactored too. Is it worth the effort? Should it be done? Personally, I am really starting to dislike the 1-1 relationship between views and controllers. Its common situation that we have 1 page (view) that handles 2 or more different resources. I think we should have views completely decoupled from controllers, but rails is giving us hard time to achieve this. I know that AJAX can be used to solve this issue, but I consider it an improvisation. Is there some other kind of architecture (other than MVC) that decouples views from controllers?

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• MvcExtensions - PerRequestTask

  - by kazimanzurrashid

  In the previous post, we have seen the BootstrapperTask which executes when the application starts and ends, similarly there are times when we need to execute some custom logic when a request starts and ends. Usually, for this kind of scenario we create HttpModule and hook the begin and end request events. There is nothing wrong with this approach, except HttpModules are not at all IoC containers friendly, also defining the HttpModule execution order is bit cumbersome, you either have to modify the machine.config or clear the HttpModules and add it again in web.config. Instead, you can use the PerRequestTask which is very much container friendly as well as supports execution orders. Lets few examples where it can be used. Remove www Subdomain Lets say we want to remove the www subdomain, so that if anybody types http://www.mydomain.com it will automatically redirects to http://mydomain.com. public class RemoveWwwSubdomain : PerRequestTask { public RemoveWww() { Order = DefaultOrder - 1; } protected override TaskContinuation ExecuteCore(PerRequestExecutionContext executionContext) { const string Prefix = "http://www."; Check.Argument.IsNotNull(executionContext, "executionContext"); HttpContextBase httpContext = executionContext.HttpContext; string url = httpContext.Request.Url.ToString(); bool startsWith3W = url.StartsWith(Prefix, StringComparison.OrdinalIgnoreCase); bool shouldContinue = true; if (startsWith3W) { string newUrl = "http://" + url.Substring(Prefix.Length); HttpResponseBase response = httpContext.Response; response.StatusCode = (int)HttpStatusCode.MovedPermanently; response.Status = "301 Moved Permanently"; response.RedirectLocation = newUrl; response.SuppressContent = true; shouldContinue = false; } return shouldContinue ? TaskContinuation.Continue : TaskContinuation.Break; } } As you can see, first, we are setting the order so that we do not have to execute the remaining tasks of the chain when we are redirecting, next in the ExecuteCore, we checking the whether www is present, if present we are sending a permanently moved http status code and breaking the task execution chain otherwise we are continuing with the chain. Blocking IP Address Lets take another scenario, your application is hosted in a shared hosting environment where you do not have the permission to change the IIS setting and you want to block certain IP addresses from visiting your application. Lets say, you maintain a list of IP address in database/xml files which you want to block, you have a IBannedIPAddressRepository service which is used to match banned IP Address. public class BlockRestrictedIPAddress : PerRequestTask { protected override TaskContinuation ExecuteCore(PerRequestExecutionContext executionContext) { bool shouldContinue = true; HttpContextBase httpContext = executionContext.HttpContext; if (!httpContext.Request.IsLocal) { string ipAddress = httpContext.Request.UserHostAddress; HttpResponseBase httpResponse = httpContext.Response; if (executionContext.ServiceLocator.GetInstance<IBannedIPAddressRepository>().IsMatching(ipAddress)) { httpResponse.StatusCode = (int)HttpStatusCode.Forbidden; httpResponse.StatusDescription = "IPAddress blocked."; shouldContinue = false; } } return shouldContinue ? TaskContinuation.Continue : TaskContinuation.Break; } } Managing Database Session Now, let see how it can be used to manage NHibernate session, assuming that ISessionFactory of NHibernate is already registered in our container. public class ManageNHibernateSession : PerRequestTask { private ISession session; protected override TaskContinuation ExecuteCore(PerRequestExecutionContext executionContext) { ISessionFactory factory = executionContext.ServiceLocator.GetInstance<ISessionFactory>(); session = factory.OpenSession(); return TaskContinuation.Continue; } protected override void DisposeCore() { session.Close(); session.Dispose(); } } As you can see PerRequestTask can be used to execute small and precise tasks in the begin/end request, certainly if you want to execute other than begin/end request there is no other alternate of HttpModule. That’s it for today, in the next post, we will discuss about the Action Filters, so stay tuned.

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• Vitality of Product Information Management Showcased at OpenWorld 2012

  - by Mala Narasimharajan

   By Sachin Patel Can you hear the countdown clock ticking!! OpenWorld 2012 is almost here and as I write this Oracle is buzzing with fresh new ideas and solutions that will be showcased this year. What an exciting time for all of us to be in midst of a digital revolution. Whether it is Apple fans clamoring to find every new feature that has been added to the iPhone 5 or a startup launching a new digital thermostat (has anyone looked at the new one from Nest ), product information is a vital for companies to grow and compete in this cut-throat market. Customer today struggle to aggregate and enrich this product data from the myriad of systems they have in place to run their businesses and operations. Having a product information strategy is paramount to align your sales channels and operations with the most accurate and upto date product data. We have a number of sessions this year at OpenWorld where you can gain more insight into how Oracle’s next generation of Fusion Applications, in this case Fusion Product Hub can provide you with a solution to streamline and get control of your Product Master Data. Enabling Trusted Enterprise Product Data with Oracle Fusion Product HubTuesday, October 2nd 11:45 am, Moscone West 2022 Join me Sachin Patel, Director of Product Strategy and Milan Bhatia, VP of Development as we discuss how you can enable trusted product master data in your enterprise. In this session we plan to cover the challenges companies face today in mastering product data. The discussion will also include how Fusion Product Hub brings new and innovative features to empower your product data owners to create a holistic and rich product definition that can be leveraged across your enterprise. We will also be joined by Pawel Fidelus from Fideltronik an Early Adopter for Fusion Product Hub who will showcase their plans to implement Fusion Product Hub and the value it will bring to Fideltronik Multichannel Fulfillment Excellence in Direct-to-Consumer Market Thursday, October 4th, 12:45 am, Moscone West 2024 Do you have multiple order capture systems? Do you have difficulty in fulfilling orders for your customers across various channels and suppliers? Mark Carson, Director, Fusion DOO and Brad Kerr, Director, AGSS will be showcasing the Fusion Distributed Order Orchestration solution and how companies can orchestrate orders from multiple order capture systems and route them to the appropriate fulfillment system. Sachin Patel, Director Product Strategy for Product MDM will highlight the business pain points in consolidating and commercializing data from a Multi Channel Commerce point of view and how Fusion Product Hub helps in allowing you to provide a single source of truth to drive a singular and rich customer experience. Oracle Fusion Supply Chain Management: Customer Adoption and Experiences                                                Wednesday, October 3rd 10:15 am, Moscone West 2003 This is a great session to attend to learn about how Fusion Supply Chain Management and Fusion Product Hub Early Adopters, including Boeing and Fideltronik are leveraging Fusion Applications to improve their Supply Chain operations. Have a great OpenWorld and see you soon!!

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• Orchestrating the Virtual Enterprise, Part II

  - by Kathryn Perry

  A guest post by Jon Chorley, Oracle's CSO & Vice President, SCM Product Strategy Almost everyone has ordered from Amazon.com at one time or another. Our orders are as likely to be fulfilled by third parties as they are by Amazon itself. To deliver the order promptly and efficiently, Amazon has to send it to the right fulfillment location and know the availability in that location. It needs to be able to track status of the fulfillment and deal with exceptions. As a virtual enterprise, Amazon's operations, using thousands of trading partners, requires a very different approach to fulfillment than the traditional 'take an order and ship it from your own warehouse' model. Amazon had no choice but to develop a complex, expensive and custom solution to tackle this problem as there used to be no product solution available. Now, other companies who want to follow similar models have a better off-the-shelf choice -- Oracle Distributed Order Orchestration (DOO).  Consider how another of our customers is using our distributed orchestration solution. This major airplane manufacturer has a highly complex business and interacts regularly with the U.S. Government and major airlines. It sits in the middle of an intricate supply chain and needed to improve visibility across its many different entities. Oracle Fusion DOO gives the company an orchestration mechanism so it could improve quality, speed, flexibility, and consistency without requiring an organ transplant of these highly complex legacy systems. Many retailers face the challenge of dealing with brick and mortar, Web, and reseller channels. They all need to be knitted together into a virtual enterprise experience that is consistent for their customers. When a large U.K. grocer with a strong brick and mortar retail operation added an online business, they turned to Oracle Fusion DOO to bring these entities together. Disturbing the Peace with Acquisitions Quite often a company's ERP system is disrupted when it acquires a new company. An acquisition can inject a new set of processes and systems -- or even introduce an entirely new business like Sun's hardware did at Oracle. This challenge has been a driver for some of our DOO customers. A large power management company is using Oracle Fusion DOO to provide the flexibility to rapidly integrate additional products and services into its central fulfillment operation. The Flip Side of Fulfillment Meanwhile, we haven't ignored similar challenges on the supply side of the equation. Specifically, how to manage complex supply in a flexible way when there are multiple trading parties involved? How to manage the supply to suppliers? How to manage critical components that need to merge in a tier two or tier three supply chain? By investing in supply orchestration solutions for the virtual enterprise, we plan to give users better visibility into their network of suppliers to help them drive down costs. We also think this technology and full orchestration process can be applied to the financial side of organizations. An example is transactions that flow through complex internal structures to minimize tax exposure. We can help companies manage those transactions effectively by thinking about the internal organization as a virtual enterprise and bringing the same solution set to this internal challenge.  The Clear Front Runner No other company is investing in solving the virtual enterprise supply chain issues like Oracle is. Oracle is in a unique position to become the gold standard in this market space. We have the infrastructure of Oracle technology. We already have an Oracle Fusion DOO application which embraces the best of what's required in this area. And we're absolutely committed to extending our Fusion solution to other use cases and delivering even more business value. Jon ChorleyChief Sustainability Officer & Vice President, SCM Product StrategyOracle Corporation

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• ifconfig networking telnet

  - by jhon

  Hi guys, I'm newbie around networking, I have a question: what I want is to telnet a specific IP/server, let us say 192.168.128.1 then, I try $telnet 192.168.128.1 Trying... and that's all.. I never get connected one of my friends made some script that "fixes" it, AFTER running it I was able to connect to the server using $telnet 192.168.128.1 $ user: unfortunately I lost that script, so I'm here requesting your help. Reading my old notes, I remember that the script performed some modification to the entries listed by ifconfig -a, I also have the ifconfig's output (copy & paste) $ ifconfig -a adapter0: flags=5e080863,c0<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST,GROUPRT,64BIT,CHECKSUM_OFFLOAD(ACTIVE),PSEG,LARGESEND,CHAIN> inet 192.168.128.150 netmask 0xffffff00 broadcast 192.168.128.255 tcp_sendspace 131072 tcp_recvspace 65536 rfc1323 0 adapter1: flags=5e080863,c0<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST,GROUPRT,64BIT,CHECKSUM_OFFLOAD(ACTIVE),PSEG,LARGESEND,CHAIN> inet 192.168.251.150 netmask 0xffffff00 broadcast 192.168.251.255 tcp_sendspace 131072 tcp_recvspace 65536 rfc1323 0 adapter2: flags=5e080863,c0<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST,GROUPRT,64BIT,CHECKSUM_OFFLOAD(ACTIVE),PSEG,LARGESEND,CHAIN> inet 192.168.250.150 netmask 0xffffff00 broadcast 192.168.250.255 tcp_sendspace 131072 tcp_recvspace 65536 rfc1323 0 lo0: flags=e08084b<UP,BROADCAST,LOOPBACK,RUNNING,SIMPLEX,MULTICAST,GROUPRT,64BIT> inet 127.0.0.1 netmask 0xff000000 broadcast 127.255.255.255 inet6 ::1/0 tcp_sendspace 131072 tcp_recvspace 131072 rfc1323 1 more than commands, I'm looking for some explanation why does "adding/changing" those entries enables me to connect to the server. I do not see the server ip (i.e 192.168.128.1) listed above. thanks

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• Comparing RPG to C# and SQL.

  - by Kevin

  In an RPG program (One of IBM's languages on the AS/400) I can "chain" out to a file to see if a record (say, a certain customer record) exists in the file. If it does, then I can update that record instantly with new data. If the record doesn't exist, I can write a new record. The code would look like this: Customer Chain CustFile 71 ;turn on indicator 71 if not found if *in71 ;if 71 is "on" eval CustID = Customer; eval CustCredit = 10000; write CustRecord else ;71 not on, record found. CustCredit = 10000; update CustRecord endif Not being real familiar with SQL/C#, I'm wondering if there is a way to do a random retrieval from a file (which is what "chain" does in RPG). Basically I want to see if a record exists. If it does, update the record with some new information. If it does not, then I want to write a new record. I'm sure it's possible, but not quite sure how to go about doing it. Any advice would be greatly appreciated.

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• filterSecurityInterceptor and metadatasource implementation spring-security

  - by Mike

  Hi! I created a class that implements the FilterInvocationSecurityMetadataSource interface. I implemented it like this: public List<ConfigAttribute> getAttributes(Object object) { FilterInvocation fi = (FilterInvocation) object; Object principal = SecurityContextHolder.getContext().getAuthentication().getPrincipal(); Long companyId = ((ExtenededUser) principal).getCompany().getId(); String url = fi.getRequestUrl(); // String httpMethod = fi.getRequest().getMethod(); List<ConfigAttribute> attributes = new ArrayList<ConfigAttribute>(); FilterSecurityService service = (FilterSecurityService) SpringBeanFinder.findBean("filterSecurityService"); Collection<Role> roles = service.getRoles(companyId); for (Role role : roles) { for (View view : role.getViews()) { if (view.getUrl().equalsIgnoreCase(url)) attributes.add(new SecurityConfig(role.getName() + "_" + role.getCompany().getName())); } } return attributes; } when I debug my application I see it reaches this class, it only reaches getAllConfigAttributes method, that is empty as I said, and return null. after that it prints this warning: Could not validate configuration attributes as the SecurityMetadataSource did not return any attributes from getAllConfigAttributes(). My aplicationContext- security is like this: <beans:bean id="filterChainProxy" class="org.springframework.security.web.FilterChainProxy"> <filter-chain-map path-type="ant"> <filter-chain filters="sif,filterSecurityInterceptor" pattern="/**" /> </filter-chain-map> </beans:bean> <beans:bean id="filterSecurityInterceptor" class="org.springframework.security.web.access.intercept.FilterSecurityInterceptor"> <beans:property name="authenticationManager" ref="authenticationManager" /> <beans:property name="accessDecisionManager" ref="accessDecisionManager" /> <beans:property name="securityMetadataSource" ref="filterSecurityMetadataSource" /> </beans:bean> <beans:bean id="filterSecurityMetadataSource" class="com.mycompany.filter.FilterSecurityMetadataSource"> </beans:bean> what could be the problem?

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• Illegal offset type error when => value is omitted

  - by thomas

  Line 3 of the code below fails if I omit the => $v portion. I get the following error: Warning: Illegal offset type in /home/site/page.php on line 404 When the [$k] in line 5 is changed to ['$k'], i receive the following error. Notice: Undefined index: $k in /home/site/page.php on line 404 When it is like below with the the full $k => $v everything works though. I don't even use $v. Why do I need it in the foreach loop to make it work then? <? if ( $arr[ 'status'][ 'chain'] ) { foreach ( $arr[ 'status'][ 'chain'] as $k => $v) { ?> <tr> <td class="line_item_data status_td"> <?= $ arr[ 'status'][ 'chain'][$k][ 'message'] ?> </td> <td align="center"> <img src="images/green_check.gif" width="20" /> </td> </tr> <? } } ?> I did see this answer, but don't know that it really applies. Thanks so much!

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