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  • CI tests to enforce specific development rules - good practice?

    - by KeithS
    The following is all purely hypothetical and any particular portion of it may or may not accurately describe real persons or situations, whether living, dead or just pretending. Let's say I'm a senior dev or architect in charge of a dev team working on a project. This project includes a security library for user authentication/authorization of the application under development. The library must be available for developers to edit; however, I wish to "trust but verify" that coders are not doing things that could compromise the security of the finished system, and because this isn't my only responsibility I want it to be done in an automated way. As one example, let's say I have an interface that represents a user which has been authenticated by the system's security library. The interface exposes basic user info and a list of things the user is authorized to do (so that the client app doesn't have to keep asking the server "can I do this?"), all in an immutable fashion of course. There is only one implementation of this interface in production code, and for the purposes of this post we can say that all appropriate measures have been taken to ensure that this implementation can only be used by the one part of our code that needs to be able to create concretions of the interface. The coders have been instructed that this interface and its implementation are sacrosanct and any changes must go through me. However, those are just words; the security library's source is open for editing by necessity. Any of my devs could decide that this secured, private, hash-checked implementation needs to be public so that they could do X, or alternately they could create their own implementation of this public interface in a different library, exposing the hashing algorithm that provides the secure checksum, in order to do Y. I may not be made aware of these changes so that I can beat the developer over the head for it. An attacker could then find these little nuggets in an unobfuscated library of the compiled product, and exploit it to provide fake users and/or falsely-elevated administrative permissions, bypassing the entire security system. This possibility keeps me awake for a couple of nights, and then I create an automated test that reflectively checks the codebase for types deriving from the interface, and fails if it finds any that are not exactly what and where I expect them to be. I compile this test into a project under a separate folder of the VCS that only I have rights to commit to, have CI compile it as an external library of the main project, and set it up to run as part of the CI test suite for user commits. Now, I have an automated test under my complete control that will tell me (and everyone else) if the number of implementations increases without my involvement, or an implementation that I did know about has anything new added or has its modifiers or those of its members changed. I can then investigate further, and regain the opportunity to beat developers over the head as necessary. Is this considered "reasonable" to want to do in situations like this? Am I going to be seen in a negative light for going behind my devs' backs to ensure they aren't doing something they shouldn't?

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  • Should I manage authentication on my own if the alternative is very low in usability and I am already managing roles?

    - by rumtscho
    As a small in-house dev department, we only have experience with developing applications for our intranet. We use the existing Active Directory for user account management. It contains the accounts of all company employees and many (but not all) of the business partners we have a cooperation with. Now, the top management wants a technology exchange application, and I am the lead dev on the new project. Basically, it is a database containing our know-how, with a web frontend. Our employees, our cooperating business partners, and people who wish to become our cooperating business partners should have access to it and see what technologies we have, so they can trade for them with the department which owns them. The technologies are not patented, but very valuable to competitors, so the department bosses are paranoid about somebody unauthorized gaining access to their technology description. This constraint necessitates a nightmarishly complicated multi-dimensional RBAC-hybrid model. As the Active Directory doesn't even contain all the information needed to infer the roles I use, I will have to manage roles plus per-technology per-user granted access exceptions within my system. The current plan is to use Active Directory for authentication. This will result in a multi-hour registration process for our business partners where the database owner has to manually create logins in our Active Directory and send them credentials. If I manage the logins in my own system, we could improve the usability a lot, for example by letting people have an active (but unprivileged) account as soon as they register. It seems to me that, after I am having a users table in the DB anyway (and managing ugly details like storing historical user IDs so that recycled user IDs within the Active Directory don't unexpectedly get rights to view someone's technologies), the additional complexity from implementing authentication functionality will be minimal. Therefore, I am starting to lean towards doing my own user login management and forgetting the AD altogether. On the other hand, I see some reasons to stay with Active Directory. First, the conventional wisdom I have heard from experienced programmers is to not do your own user management if you can avoid it. Second, we have code I can reuse for connection to the active directory, while I would have to code the authentication if done in-system (and my boss has clearly stated that getting the project delivered on time has much higher priority than delivering a system with high usability). Third, I am not a very experienced developer (this is my first lead position) and have never done user management before, so I am afraid that I am overlooking some important reasons to use the AD, or that I am underestimating the amount of work left to do my own authentication. I would like to know if there are more reasons to go with the AD authentication mechanism. Specifically, if I want to do my own authentication, what would I have to implement besides a secure connection for the login screen (which I would need anyway even if I am only transporting the pw to the AD), lookup of a password hash and a mechanism for password recovery (which will probably include manual identity verification, so no need for complex mTAN-like solutions)? And, if you have experience with such security-critical systems, which one would you use and why?

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  • Approach for packing 2D shapes while minimizing total enclosing area

    - by Dennis
    Not sure on my tags for this question, but in short .... I need to solve a problem of packing industrial parts into crates while minimizing total containing area. These parts are motors, or pumps, or custom-made components, and they have quite unusual shapes. For some, it may be possible to assume that a part === rectangular cuboid, but some are not so simple, i.e. they assume a shape more of that of a hammer or letter T. With those, (assuming 2D shape), by alternating direction of top & bottom, one can pack more objects into the same space, than if all tops were in the same direction. Crude example below with letter "T"-shaped parts: ***** xxxxx ***** x ***** *** ooo * x vs * x vs * x vs * x o * x * xxxxx * x * x o xxxxx xxx Right now we are solving the problem by something like this: using CAD software, make actual models of how things fit in crate boxes make estimates of actual crate dimensions & write them into Excel file (1) is crazy amount of work and as the result we have just a limited amount of possible entries in (2), the Excel file. The good things is that programming this is relatively easy. Given a combination of products to go into crates, we do a lookup, and if entry exists in the Excel (or Database), we bring it out. If it doesn't, we say "sorry, no data!". I don't necessarily want to go full force on making up some crazy algorithm that given geometrical part description can align, rotate, and figure out best part packing into a crate, given its shape, but maybe I do.. Question Well, here is my question: assuming that I can represent my parts as 2D (to be determined how), and that some parts look like letter T, and some parts look like rectangles, which algorithm can I use to give me a good estimate on the dimensions of the encompassing area, while ensuring that the parts are packed in a minimal possible area, to minimize crating/shipping costs? Are there approximation algorithms? Seeing how this can get complex, is there an existing library I could use? My thought / Approach My naive approach would be to define a way to describe position of parts, and place the first part, compute total enclosing area & dimensions. Then place 2nd part in 0 degree orientation, repeat, place it at 180 degree orientation, repeat (for my case I don't think 90 degree rotations will be meaningful due to long lengths of parts). Proceed using brute force "tacking on" other parts to the enclosing area until all parts are processed. I may have to shift some parts a tad (see 3rd pictorial example above with letters T). This adds a layer of 2D complexity rather than 1D. I am not sure how to approach this. One idea I have is genetic algorithms, but I think those will take up too much processing power and time. I will need to look out for shape collisions, as well as adding extra padding space, since we are talking about real parts with irregularities rather than perfect imaginary blocks. I'm afraid this can get geometrically messy fairly fast, and I'd rather keep things simple, if I can. But what if the best (practical) solution is to pack things into different crate boxes rather than just one? This can get a bit more tricky. There is human element involved as well, i.e. like parts can go into same box and are thus a constraint to be considered. Some parts that are not the same are sometimes grouped together for shipping and can be considered as a common grouped item. Sometimes customers want things shipped their way, which adds human element to constraints. so there will have to be some customization.

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  • Framework for Everything - Where to begin? [Longer post]

    - by SquaredSoft
    Back story of this question, feel free to skip down for the specific question Hello, I've been very interested in the idea of abstract programming the last few years. I've made about 30 attempts at creating a piece of software that is capable of almost anything you throw at it. I've undertook some attempts at this that have taken upwards of a year, while getting close, never releasing it beyond my compiler. This has been something I've always tried wrapping my head around, and something is always missing. With the title, I'm sure you're assuming, "Yes of course you noob! You can't account for everything!" To which I have to reply, "Why not?" To give you some background into what I'm talking about, this all started with doing maybe a shade of gray hat SEO software. I found myself constantly having to create similar, but slightly different sets of code. I've gone through as many iterations of way to communicate on http as the universe has particles. "How many times am I going to have to write this multi-threaded class?" is something I found myself asking a lot. Sure, I could create a class library, and just work with that, but I always felt I could optimize what I had, which often was a large undertaking and typically involved frequent use of the CRTL+A keyboard shortcut, mixed with the delete button. It dawned on me that it was time to invest in a plugin system. This would allow me to simply add snippets of code. as time went on, and I could subversion stuff out, and distribute small chunks of code, rather than something that encompasses only a specific function or design. This comes with its own complexity, of course, and by the time I had finished the software scope for this addition, it hit me that I would want to add to everything in the software, not just a new http method, or automation code for a specific website. Great, we're getting more abstract. However, the software that I have in my mind comes down to a quite a few questions regarding its execution. I have to have some parameters to what I am going to do. After writing what the perfect software would do in my mind, I came up with this as a list of requirements: Should be able to use networking A "Macro" or "Expression system" which would allow people to do something like : =First(=ParseToList(=GetUrl("http://www.google.com?q=helloworld!"), Template.Google)) Multithreaded Able to add UI elements through some type of XML -- People can make their own addons etc. Can use third party API through the plugins, such as Microsoft CRM, Exchange, etc. This would allow the software to essentially be used for everything. Really, any task you wish to automate, in a simple way. Making the UI was as also extremely hard. How do you do all of this? Its very difficult. So my question: With so many attempts at this, I'm out of ideas how to successfully complete this. I have a very specific idea in my mind, but I keep failing to execute it. I'm a self taught programmer. I've been doing it for years, and work professionally in it, but I've never encountered something that would be as complex and in-depth as a system which essentially does everything. Where would you start? What are the best practices for design? How can I avoid constantly having to go back and optimize my software. What can I do to generalize this and draw everything out to completion. These are things I struggle with. P.s., I'm using c# as my main language. I feel like in this example, I might be hitting the outer limit of the language, although, I don't know if that is the case, or if I'm just a bad programmer. Thanks for your time.

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  • Bounding Box Collision Glitching Problem (Pygame)

    - by Ericson Willians
    So far the "Bounding Box" method is the only one that I know. It's efficient enough to deal with simple games. Nevertheless, the game I'm developing is not that simple anymore and for that reason, I've made a simplified example of the problem. (It's worth noticing that I don't have rotating sprites on my game or anything like that. After showing the code, I'll explain better). Here's the whole code: from pygame import * DONE = False screen = display.set_mode((1024,768)) class Thing(): def __init__(self,x,y,w,h,s,c): self.x = x self.y = y self.w = w self.h = h self.s = s self.sur = Surface((64,48)) draw.rect(self.sur,c,(self.x,self.y,w,h),1) self.sur.fill(c) def draw(self): screen.blit(self.sur,(self.x,self.y)) def move(self,x): if key.get_pressed()[K_w] or key.get_pressed()[K_UP]: if x == 1: self.y -= self.s else: self.y += self.s if key.get_pressed()[K_s] or key.get_pressed()[K_DOWN]: if x == 1: self.y += self.s else: self.y -= self.s if key.get_pressed()[K_a] or key.get_pressed()[K_LEFT]: if x == 1: self.x -= self.s else: self.x += self.s if key.get_pressed()[K_d] or key.get_pressed()[K_RIGHT]: if x == 1: self.x += self.s else: self.x -= self.s def warp(self): if self.y < -48: self.y = 768 if self.y > 768 + 48: self.y = 0 if self.x < -64: self.x = 1024 + 64 if self.x > 1024 + 64: self.x = -64 r1 = Thing(0,0,64,48,1,(0,255,0)) r2 = Thing(6*64,6*48,64,48,1,(255,0,0)) while not DONE: screen.fill((0,0,0)) r2.draw() r1.draw() # If not intersecting, then moves, else, it moves in the opposite direction. if not ((((r1.x + r1.w) > (r2.x - r1.s)) and (r1.x < ((r2.x + r2.w) + r1.s))) and (((r1.y + r1.h) > (r2.y - r1.s)) and (r1.y < ((r2.y + r2.h) + r1.s)))): r1.move(1) else: r1.move(0) r1.warp() if key.get_pressed()[K_ESCAPE]: DONE = True for ev in event.get(): if ev.type == QUIT: DONE = True display.update() quit() The problem: In my actual game, the grid is fixed and each tile has 64 by 48 pixels. I know how to deal with collision perfectly if I moved by that size. Nevertheless, obviously, the player moves really fast. In the example, the collision is detected pretty well (Just as I see in many examples throughout the internet). The problem is that if I put the player to move WHEN IS NOT intersecting, then, when it touches the obstacle, it does not move anymore. Giving that problem, I began switching the directions, but then, when it touches and I press the opposite key, it "glitches through". My actual game has many walls, and the player will touch them many times, and I can't afford letting the player go through them. The code-problem illustrated: When the player goes towards the wall (Fine). When the player goes towards the wall and press the opposite direction. (It glitches through). Here is the logic I've designed before implementing it: I don't know any other method, and I really just want to have walls fixed in a grid, but move by 1 or 2 or 3 pixels (Slowly) and have perfect collision without glitching-possibilities. What do you suggest?

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  • Intern Screening - Software 'Quiz'

    - by Jeremy1026
    I am in charge of selecting a new software development intern for a company that I work with. I wanted to throw a little 'quiz' at the applicants before moving forth with interviews so as to weed out the group a little bit to find some people that can demonstrate some skill. I put together the following quiz to send to applicants, it focuses only on PHP, but that is because that is what about 95% of the work will be done in. I'm hoping to get some feedback on A. if its a good idea to send this to applicants and B. if it can be improved upon. # 1. FizzBuzz # Write a small application that does the following: # Counts from 1 to 100 # For multiples of 3 output "Fizz" # For multiples of 5 output "Buzz" # For multiples of 3 and 5 output "FizzBuzz" # For numbers that are not multiples of 3 nor 5 output the number. <?php ?> # 2. Arrays # Create a multi-dimensional array that contains # keys for 'id', 'lot', 'car_model', 'color', 'price'. # Insert three sets of data into the array. <?php ?> # 3. Comparisons # Without executing the code, tell if the expressions # below will return true or false. <?php if ((strpos("a","abcdefg")) == TRUE) echo "True"; else echo "False"; //True or False? if ((012 / 4) == 3) echo "True"; else echo "False"; //True or False? if (strcasecmp("abc","ABC") == 0) echo "True"; else echo "False"; //True or False? ?> # 4. Bug Checking # The code below is flawed. Fix it so that the code # runs properly without producing any Errors, Warnings # or Notices, and returns the proper value. <?php //Determine how many parts are needed to create a 3D pyramid. function find_3d_pyramid($rows) { //Loop through each row. for ($i = 0; $i < $rows; $i++) { $lastRow++; //Append the latest row to the running total. $total = $total + (pow($lastRow,3)); } //Return the total. return $total; } $i = 3; echo "A pyramid consisting of $i rows will have a total of ".find_3d_pyramid($i)." pieces."; ?> # 5. Quick Examples # Create a small example to complete the task # for each of the following problems. # Create an md5 hash of "Hello World"; # Replace all occurances of "_" with "-" in the string "Welcome_to_the_universe." # Get the current date and time, in the following format, YYYY/MM/DD HH:MM:SS AM/PM # Find the sum, average, and median of the following set of numbers. 1, 3, 5, 6, 7, 9, 10. # Randomly roll a six-sided die 5 times. Store the 5 rolls into an array. <?php ?>

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  • Data breakpoints to find points where data gets broken

    - by raccoon_tim
    When working with a large code base, finding reasons for bizarre bugs can often be like finding a needle in a hay stack. Finding out why an object gets corrupted without no apparent reason can be quite daunting, especially when it seems to happen randomly and totally out of context. Scenario Take the following scenario as an example. You have defined the a class that contains an array of characters that is 256 characters long. You now implement a method for filling this buffer with a string passed as an argument. At this point you mistakenly expect the buffer to be 256 characters long. At some point you notice that you require another character buffer and you add that after the previous one in the class definition. You now figure that you don’t need the 256 characters that the first member can hold and you shorten that to 128 to conserve space. At this point you should start thinking that you also have to modify the method defined above to safeguard against buffer overflow. It so happens, however, that in this not so perfect world this does not cross your mind. Buffer overflow is one of the most frequent sources for errors in a piece of software and often one of the most difficult ones to detect, especially when data is read from an outside source. Many mass copy functions provided by the C run-time provide versions that have boundary checking (defined with the _s suffix) but they can not guard against hard coded buffer lengths that at some point get changed. Finding the bug Getting back to the scenario, you’re now wondering why does the second string get modified with data that makes no sense at all. Luckily, Visual Studio provides you with a tool to help you with finding just these kinds of errors. It’s called data breakpoints. To add a data breakpoint, you first run your application in debug mode or attach to it in the usual way, and then go to Debug, select New Breakpoint and New Data Breakpoint. In the popup that opens, you can type in the memory address and the amount of bytes you wish to monitor. You can also use an expression here, but it’s often difficult to come up with an expression for data in an object allocated on the heap when not in the context of a certain stack frame. There are a couple of things to note about data breakpoints, however. First of all, Visual Studio supports a maximum of four data breakpoints at any given time. Another important thing to notice is that some C run-time functions modify memory in kernel space which does not trigger the data breakpoint. For instance, calling ReadFile on a buffer that is monitored by a data breakpoint will not trigger the breakpoint. The application will now break at the address you specified it to. Often you might immediately spot the issue but the very least this feature can do is point you in the right direction in search for the real reason why the memory gets inadvertently modified. Conclusions Data breakpoints are a great feature, especially when doing a lot of low level operations where multiple locations modify the same data. With the exception of some special cases, like kernel memory modification, you can use it whenever you need to check when memory at a certain location gets changed on purpose or inadvertently.

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  • When should I use a Process Model versus a Use Case?

    - by Dave Burke
    This Blog entry is a follow on to https://blogs.oracle.com/oum/entry/oum_is_business_process_and and addresses a question I sometimes get asked…..i.e. “when I am gathering requirements on a Project, should I use a Process Modeling approach, or should I use a Use Case approach?” Not surprisingly, the short answer is “it depends”! Let’s take a scenario where you are working on a Sales Force Automation project. We’ll call the process that is being implemented “Lead-to-Order”. I would typically think of this type of project as being “Process Centric”. In other words, the focus will be on orchestrating a series of human and system related tasks that ultimately deliver value to the business in a cost effective way. Put in even simpler terms……implement an automated pre-sales system. For this type of (Process Centric) project, requirements would typically be gathered through a series of Workshops where the focal point will be on creating, or confirming, the Future-State (To-Be) business process. If pre-defined “best-practice” business process models exist, then of course they could and should be used during the Workshops, but even in their absence, the focus of the Workshops will be to define the optimum series of Tasks, their connections, sequence, and dependencies that will ultimately reflect a business process that meets the needs of the business. Now let’s take another scenario. Assume you are working on a Content Management project that involves automating the creation and management of content for User Manuals, Web Sites, Social Media publications etc. Would you call this type of project “Process Centric”?.......well you could, but it might also fall into the category of complex configuration, plus some custom extensions to a standard software application (COTS). For this type of project it would certainly be worth considering using a Use Case approach in order to 1) understand the requirements, and 2) to capture the functional requirements of the custom extensions. At this point you might be asking “why couldn’t I use a Process Modeling approach for my Content Management project?” Well, of course you could, but you just need to think about which approach is the most effective. Start by analyzing the types of Tasks that will eventually be automated by the system, for example: Best Suited To? Task Name Process Model Use Case Notes Manage outbound calls Ö A series of linked human and system tasks for calling and following up with prospects Manage content revision Ö Updating the content on a website Update User Preferences Ö Updating a users display preferences Assign Lead Ö Reviewing a lead, then assigning it to a sales person Convert Lead to Quote Ö Updating the status of a lead, and then converting it to a sales order As you can see, it’s not an exact science, and either approach is viable for the Tasks listed above. However, where you have a series of interconnected Tasks or Activities, than when combined, deliver value to the business, then that would be a good indicator to lead with a Process Modeling approach. On the other hand, when the Tasks or Activities in question are more isolated and/or do not cross traditional departmental boundaries, then a Use Case approach might be worth considering. Now let’s take one final scenario….. As you captured the To-Be Process flows for the Sales Force automation project, you discover a “Gap” in terms of what the client requires, and what the standard COTS application can provide. Let’s assume that the only way forward is to develop a Custom Extension. This would now be a perfect opportunity to document the functional requirements (behind the Gap) using a Use Case approach. After all, we will be developing some new software, and one of the most effective ways to begin the Software Development Lifecycle is to follow a Use Case approach. As always, your comments are most welcome.

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  • Entity System with C++ templates

    - by tommaisey
    I've been getting interested in the Entity/Component style of game programming, and I've come up with a design in C++ which I'd like a critique of. I decided to go with a fairly pure Entity system, where entities are simply an ID number. Components are stored in a series of vectors - one for each Component type. However, I didn't want to have to add boilerplate code for every new Component type I added to the game. Nor did I want to use macros to do this, which frankly scare me. So I've come up with a system based on templates and type hinting. But there are some potential issues I'd like to check before I spend ages writing this (I'm a slow coder!) All Components derive from a Component base class. This base class has a protected constructor, that takes a string parameter. When you write a new derived Component class, you must initialise the base with the name of your new class in a string. When you first instantiate a new DerivedComponent, it adds the string to a static hashmap inside Component mapped to a unique integer id. When you subsequently instantiate more Components of the same type, no action is taken. The result (I think) should be a static hashmap with the name of each class derived from Component that you instantiate at least once, mapped to a unique id, which can by obtained with the static method Component::getTypeId ("DerivedComponent"). Phew. The next important part is TypedComponentList<typename PropertyType>. This is basically just a wrapper to an std::vector<typename PropertyType> with some useful methods. It also contains a hashmap of entity ID numbers to slots in the array so we can find Components by their entity owner. Crucially TypedComponentList<> is derived from the non-template class ComponentList. This allows me to maintain a list of pointers to ComponentList in my main ComponentManager, which actually point to TypedComponentLists with different template parameters (sneaky). The Component manager has template functions such as: template <typename ComponentType> void addProperty (ComponentType& component, int componentTypeId, int entityId) and: template <typename ComponentType> TypedComponentList<ComponentType>* getComponentList (int componentTypeId) which deal with casting from ComponentList to the correct TypedComponentList for you. So to get a list of a particular type of Component you call: TypedComponentList<MyComponent>* list = componentManager.getComponentList<MyComponent> (Component::getTypeId("MyComponent")); Which I'll admit looks pretty ugly. Bad points of the design: If a user of the code writes a new Component class but supplies the wrong string to the base constructor, the whole system will fail. Each time a new Component is instantiated, we must check a hashed string to see if that component type has bee instantiated before. Will probably generate a lot of assembly because of the extensive use of templates. I don't know how well the compiler will be able to minimise this. You could consider the whole system a bit complex - perhaps premature optimisation? But I want to use this code again and again, so I want it to be performant. Good points of the design: Components are stored in typed vectors but they can also be found by using their entity owner id as a hash. This means we can iterate them fast, and minimise cache misses, but also skip straight to the component we need if necessary. We can freely add Components of different types to the system without having to add and manage new Component vectors by hand. What do you think? Do the good points outweigh the bad?

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  • WCF ChannelFactory caching

    - by Myles J
    I've just read this great article on WCF ChannelFactory caching by Wenlong Dong. My question is simply how can you actually prove that the ChannelFactory is in fact being cached between calls? I've followed the rules regarding the ClientBase’s constructors. We are using the following overloaded constructor on our object that inherits from ClientBase: ClientBase(string endpointConfigurationName, EndpointAddress remoteAddress); In the article mentioned above it is stated that: For these constructors, all arguments (including default ones) are in the following list: · InstanceContext callbackInstance · string endpointConfigurationName · EndpointAddress remoteAddress As long as these three arguments are the same when ClientBase is constructed, we can safely assume that the same ChannelFactory can be used. Fortunately, String and EndpointAddress types are immutable, i.e., we can make simple comparison to determine whether two arguments are the same. For InstanceContext, we can use Object reference comparison. The type EndpointTrait is thus used as the key of the MRU cache. To test the ChannelFactory cache theory we are checking the Hashcode in the ClientBase constructor e.g. var testHash = RuntimeHelpers.GetHashCode(base.ChannelFactory); The hash value is different between calls which makes us think that the ChannelFactory isn't actually cached. Any thoughts? Regards Myles

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  • Sample code from apple iPhoneMultichannelMixerTest can't run mp3 file

    - by Usman
    Hi i want to control channel volume from my app and iPhoneMultichannelMixerTest (http://developer.apple.com/iphone/library/samplecode/iPhoneMultichannelMixerTest/)sample code form apple looks perfect for me. but i m heaving problem in playing mp3 files. code crashes in MultichannelMixerController.m at static OSStatus renderInput(void *inRefCon, AudioUnitRenderActionFlags *ioActionFlags, const AudioTimeStamp *inTimeStamp, UInt32 inBusNumber, UInt32 inNumberFrames, AudioBufferList *ioData) { SoundBufferPtr sndbuf = (SoundBufferPtr)inRefCon; UInt32 bufSamples = sndbuf[inBusNumber].numFrames; AudioUnitSampleType *in = sndbuf[inBusNumber].data; AudioUnitSampleType *outA = (AudioUnitSampleType *)ioData->mBuffers[0].mData; AudioUnitSampleType *outB = (AudioUnitSampleType *)ioData->mBuffers[1].mData; UInt32 sample = sndbuf[inBusNumber].sampleNum; for (UInt32 i = 0; i < inNumberFrames; ++i) { if (1 == inBusNumber) { outA[i] = 0; outB[i] = in[sample++]; //crash on this line. } else { outA[i] = in[sample++]; outB[i] = 0; } if (sample >= bufSamples) sample = 0; } sndbuf[inBusNumber].sampleNum = sample; // printf("bus %d sample %d\n", inBusNumber, sample); return noErr; } can any one tell me why this is happening. or is there any limitation to play mp3 on iPhone??? Thankz in Adv. Usman

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  • Reset scale/width/zoom of Safari on iPhone using JavaScript/onorientationchange

    - by dwarbi
    I am displaying different content depending on how the user is holding his/her phone using the onorientationchange call in the body tag. This works great - I hide one div while making the other visible. The div in portrait mode looks great on first load. I use this to get the right scale/zoom: <meta name="viewport" content="width=device-width; initial-scale=1.0; maximum-scale=1.0;" /> Even if the content in portrait mode run over, the width is correct and the user can scroll down. The display in landscape mode is perfect too. However, if content in landscape mode requires the user the scroll down, then when the user returns to portrait mode, the screen is "zoomed out" so to speak. This happens whether or not the user scrolled down while in landscape mode. I've tried many different things to try to get the scale/zoom/width of the screen right, but no luck. Is there any way to do this? Thanks in advance!

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  • expecting tASSOC in a Rails file

    - by steven_noble
    I'm sure I've done something stupid here, but I just can't see it. I call the breadcrumb method in the application view. app/helpers/breadcrumbs_helper.rb says: module BreadcrumbsHelper def breadcrumb @crumb_list = [] drominay_crumb_builder project_crumb_builder content_tag(:div, :id => "breadcrumbs", @crumb_list.map { |list_item| crumb_builder(list_item) }) end def crumb_builder(list_item) if list_item == @crumb_list.last content_tag(:span, list_item['body'], :class => list_item['crumb']) else body = ["list_item['body']", "&nbsp;&#x2192;&nbsp;"].join link_to(body, list_item['url'], :class => list_item['crumb']) end end def drominay_crumb_builder list_item = Hash.new list_item['body'] = "Drominay" list_item['url'] = "root" @crumb_list << list_item end def project_crumb_builder end end Why oh why am I getting this "expecting tASSOC" error? (And what is a tASSOC anyway?) steven-nobles-imac-200:drominay steven$ script/server => Booting Mongrel (use 'script/server webrick' to force WEBrick) => Rails 2.2.2 application starting on http://0.0.0.0:3000 => Call with -d to detach => Ctrl-C to shutdown server ** Starting Mongrel listening at 0.0.0.0:3000 ** Starting Rails with development environment... Exiting /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `gem_original_require': /Users/steven/Drominay/app/helpers/breadcrumbs_helper.rb:7: syntax error, unexpected ')', expecting tASSOC (SyntaxError) /Users/steven/Drominay/app/helpers/breadcrumbs_helper.rb:29: syntax error, unexpected $end, expecting kEND from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `require' from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:153:in `require' from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:521:in `new_constants_in' from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:153:in `require' from /Users/steven/Drominay/app/helpers/application_helper.rb:5 from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:382:in `load_without_new_constant_marking' from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:382:in `load_file' from /Library/Ruby/Gems/1.8/gems/activesupport-2.2.2/lib/active_support/dependencies.rb:521:in `new_constants_in' ... 56 levels... from /Users/steven/.gem/ruby/1.8/gems/rails-2.2.2/lib/commands/server.rb:49 from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `gem_original_require' from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:31:in `require' from script/server:3

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  • How to preserve the aspect ratio of video using AVAssetWriter

    - by Satoshi Nakajima
    I have a following code, which captures the video from the camera and stores it as a QuickMovie file using AVAssetWriter. It works fine, but the aspect ratio is not perfect because the width and height are hardcoded (480 x 320) in the outputSettings for AVAssetWriterInput. I'd rather find out the aspect ratio of the source video, and specify the appropriate height (480 x aspect ratio). Does anybody know how to do it? Should I defer the creation of AssetWriterInput until the first sampleBuffer? // set the sessionPreset to 'medium' self.captureSession = [[AVCaptureSession alloc] init]; self.captureSession.sessionPreset = AVCaptureSessionPresetMedium; ... // create AVCaptureVideoDataOutput self.captureVideo = [[AVCaptureVideoDataOutput alloc] init]; NSString* formatTypeKey = (NSString*)kCVPixelBufferPixelFormatTypeKey; self.captureVideo.videoSettings = @{ formatTypeKey:[NSNumber numberWithInt:kCVPixelFormatType_32BGRA] }; [self.captureVideo setSampleBufferDelegate:self queue:dispatch_get_main_queue()]; // create an AVAssetWriter NSError* error = nil; self.videoWriter = [[AVAssetWriter alloc] initWithURL:url fileType:AVFileTypeQuickTimeMovie error:&error]; ... // create AVAssetWriterInput with specified settings NSDictionary* compression = @{ AVVideoAverageBitRateKey:[NSNumber numberWithInt:960000], AVVideoMaxKeyFrameIntervalKey:[NSNumber numberWithInt:1] }; self.videoInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:@{ AVVideoCodecKey:AVVideoCodecH264, AVVideoCompressionPropertiesKey:compression, AVVideoWidthKey:[NSNumber numberWithInt:480], // required AVVideoHeightKey:[NSNumber numberWithInt:320] // required }]; // add it to the AVAssetWriter [self.videoWriter addInput:self.videoInput];

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  • SSRS 2008: is it possible to make a report parameter NOT query-based for some linked report?

    - by Stefan Mohr
    I suspect the answer is no, but here goes.. I'm using the WebForms Report Viewer on a public-facing website to allow users to report on themselves or their users (if the user is an admin user). A report has a parameter called Users where an admin can pick a user from the list and generate a report from it. Mundane users can also view this report, but I programmatically create a linked report for each user and set the UserID value to their ID so they can only view themselves. This works well except that the UserID parameter is query-based, and not every user is visible in the list using default settings (the user list is based off date range parameters can provide, and only users we consider 'active' during the date range are visible). This is blowing up for mundane users that are not active for the default date range (which is the previous month). I suspect the flow of execution is something like this: Report loads with default parameters The linked report rules are now applied and the value of the UserID is overridden with the ID in the linked report UserID field is now hidden to prevent the user from changing it SSRS can't find the UserID default value in the query results (that I didn't even want it to run) so it displays an error The 'UserID' parameter is missing a value Through some testing I've found a perfect correlation between users not inside the default date range and users who can't view the report. Can anyone suggest a way to make the report usable for those users that aren't in the default list? The reports are created programmatically so I do have a fair bit of control over the situation. I would love to simply be able to mark a parameter in a linked report as no longer being query-based, but those properties are all read-only. I really, really don't want to have to create duplicate reports to accommodate these users but I'm at a bit of a loss right now. Any suggestions are greatly appreciated!

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  • Nokogiri pull parser (Nokogiri::XML::Reader) issue with self closing tag

    - by Vlad Zloteanu
    I have a huge XML(400MB) containing products. Using a DOM parser is therefore excluded, so i tried to parse and process it using a pull parser. Below is a snippet from the each_product(&block) method where i iterate over the product list. Basically, using a stack, i transform each <product> ... </product> node into a hash and process it. while (reader.read) case reader.node_type #start element when Nokogiri::XML::Node::ELEMENT_NODE elem_name = reader.name.to_s stack.push([elem_name, {}]) #text element when Nokogiri::XML::Node::TEXT_NODE, Nokogiri::XML::Node::CDATA_SECTION_NODE stack.last[1] = reader.value #end element when Nokogiri::XML::Node::ELEMENT_DECL return if stack.empty? elem = stack.pop parent = stack.last if parent.nil? yield(elem[1]) elem = nil next end key = elem[0] parent_childs = parent[1] # ... parent_childs[key] = elem[1] end The issue is on self-closing tags (EG <country/>), as i can not make the difference between a 'normal' and a 'self-closing' tag. They both are of type Nokogiri::XML::Node::ELEMENT_NODE and i am not able to find any other discriminator in the documentation. Any ideas on how to solve this issue?

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  • Copy protection and licensing tools.

    - by Skittles
    I'm new to stackoverflow.com after hearing about it from Jon Skeet on DotNetRocks.This seems like the perfect place to ask this question. I am in the middle of trying to find a 3rd party Copy protection and licensing tool. The company that I work with have 4 products that need to be protected. We want to supply a Trail license (with extensions). A single user license and a floating license (where the client purchases a number to run over a network). We also want to be able to supply both the Single and Floating license as a subscription license. I have trialled DeployLX and although it seems to give everything that we need, and they are quick to answer emails, their documentation is truly awful with NO examples of how to achieve results. Has anyone any experience with DeployLX and if so, would you recommend it? Could you point me in the direction to find some real help on it? Finally, would anyone have any recommendations of a 3rd party licensing tool to use for very quick development. Thank you so much,

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  • Serialization of Queue type- Serialization not working; C#

    - by Soham
    Hi All, Consider this piece of code: private Queue Date=new Queue(); //other declarations public DateTime _Date { get { return (DateTime)Date.Peek();} set { Date.Enqueue(value); } } //other properties and stuff.... public void UpdatePosition(...) { //other code IFormatter formatter = new BinaryFormatter(); Stream Datestream = new MemoryStream(); formatter.Serialize(Datestream, Date); byte[] Datebin = new byte[2048]; Datestream.Read(Datebin,0,2048); //Debug-Bug Console.WriteLine(Convert.ToString(this._Date)); Console.WriteLine(BitConverter.ToString(Datebin, 0, 3)); //other code } The output of the first writeline is perfect. I.e to check if really the Queue is initialised or not. It is. The right variables are stored and et. all [I inserted a value in that Q, that part of the code is not shown] But the second writeline is not giving the right expected answer: It serializes the entire Queue to 00-00-00. Want some serious help! Soham

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  • Confused about home screen widget size in normal screen and larget screen

    - by kknight
    I am designing a home screen widget. The widget layout file is like below. <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/widget" android:layout_width="240dip" android:layout_height="200dip" android:background="@drawable/base_all" /> I ran this widget on a HTC Hero device, which has a screen of 320 pixels * 480 pixels with mdpi. It ran perfect on HTC Hero. The widget takes 3 cells * 2 cells space, i.e. 240 pixels * 200 pixels. Then I ran this widget on a Nexus One device, which has a screen of 480 pixels * 800 pixels, mdpi. Since Nexus One also is mdpi, so I though 240dip is equivalent to 240 pixels on Nexus One and 200dip is equivalent to 200 pixels on Nexus One, so the widget will not take 3 cells * 2 cells space on Nexus One device. To my surprise, when running on Nexus One device, the widget take exact 3 cells * 2 cells, about 360 pixels * 300 pixels, on Nexus One device. I am confused. The layout xml above specifies 240dip in width and 200dip in height for the widget, but why did it take 360 pixels * 300 pixels on Nexus One Device? What am I missing? Thanks.

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  • ActiveRecordStore ruby

    - by Andy
    I've had two previous questions about active record store that all came down to the same thing. Here's what I want: I want to access the session at any time and see who is online right now and access their session variable from anywhere. I need this because: Users are separated into groups. If one person logs in he receives an api token that I receive from some third party site. If a person from the same group logs in he needs to have that same api token in his session. I cannot regenerate new api tokens on a per call basis. I think active record store is a perfect solution for me, however, I have a problem implementing it!!! InvalidAuthenticityToken keeps getting thrown because I used to use the default cookie store. Thus I made this script to delete cookies but it does not seem to work: In application controller after_filter :delete_cookie def delete_cookie puts "deleting cookies" cookies.to_hash.each_pair do |k, v| puts k cookies.delete(k) end end The only other response I got was to remove protect from forgery. http://stackoverflow.com/questions/2941664/activerecordstore-invalidauthenticitytoken

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  • MATLAB Builder NE crash apppool on IIS 7.5

    - by Alkersan
    Im developing a web user interface for MATLAB functions with ASP.NET. Ive started with studying demos and stucked with such problem. I created a MyComponent.dll assembly with deploytool from MATLAB 2010a, target framework - 3.5. This component has one function GetKnot() which returns a figure. function df = getKnot() f = figure('Visible', 'off'); knot; df = webfigure(f); close(f); end Then I made simple webapp in visual studio 2008 sp1, with only one page Default.aspx. I added references to MWArray.dll, WebFiguresService.dll and MyComponent.dll. The codeBehind is: using System; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using MyComponent; using MathWorks.MATLAB.NET.WebFigures; namespace MATLAB_WebApplication { public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { var myComponentClass = new MyComponentClass(); var x = myComponentClass.getKnot(); //WebFigureControl1.WebFigure = new WebFigure(); } } } When I run this page on Visual Studio`s Development web server - everything is fine, figure works. But when I`m trying to deploy webfigure on my local iis 7.5 which runs on Win7 x32 - iis app pool crashes. There is an entry in System Event Log "A process serving application pool 'Classic .NET AppPool' suffered a fatal communication error with the Windows Process Activation Service. The process id was '3676'. The data field contains the error number 6D000780". This happens when MyComponent is instantiating. What I could forget when moved to IIS? Other examples, like magic square console application, runs perfect, and every matlab component instantiating, but not in IIS environment.

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  • Using Java PDFBox library to write Russian PDF

    - by Brad
    I am using a Java library called PDFBox trying to write text to a PDF. It works perfect for English text, but when i tried to write Russian text inside the PDF the letters appeared so strange. It seems the problem is in the font used, but i am not so sure about that, so i hope if anyone could guide me through this. Here is the important code lines : PDTrueTypeFont font = PDTrueTypeFont.loadTTF( pdfFile, new File( "fonts/VREMACCI.TTF" ) ); // Windows Russian font imported to write the Russian text. font.setEncoding( new WinAnsiEncoding() ); // Define the Encoding used in writing. // Some code here to open the PDF & define a new page. contentStream.drawString( "??????? ????????????" ); // Write the Russian text. The WinAnsiEncoding source code is : Click here --------------------- Edit on 18 November 2009 After some investigation, i am now sure it is an Encoding problem, this could be solved by defining my own Encoding using the helpful PDFBox class called DictionaryEncoding. I am not sure how to use it, but here is what i have tried until now : COSDictionary cosDic = new COSDictionary(); cosDic.setString( COSName.getPDFName("Ercyrillic"), "0420 " ); // Russian letter. font.setEncoding( new DictionaryEncoding( cosDic ) ); This does not work, as it seems i am filling the dictionary in a wrong way, when i write a PDF page using this it appears blank. The DictionaryEncoding source code is : Click here Thanks . . .

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  • Mysql Algorithm for Determining Closest Colour Match

    - by buggedcom
    I'm attempting to create a true mosaic application. At the moment I have one mosaic image, ie the one the mosaic is based on and about 4000 images from my iPhoto library that act as the image library. I have already done my research and analysed the mosaic image. I've converted it into 64x64 slices each of 8 pixels. I've calculated the average colour for each slice and assertain the r, g, b and brightness (Luminance (perceived option 1) = (0.299*R + 0.587*G + 0.114*B)) value. I have done the same for each of the image library photos. The mosaic slices table looks like so. slice_id, slice_image_id, slice_slice_id, slice_image_column, slice_image_row, slice_colour_hex, slice_rgb_red, slice_rgb_blue, slice_rgb_green, slice_rgb_brightness The image library table looks like so. upload_id, upload_file, upload_colour_hex, upload_rgb_red, upload_rgb_green, upload_rgb_blue, upload_rgb_brightness So basically I'm reading the image slices from the slices table into PHP and then pulling out the appropriate images from the library table based on the colour hexs. My trouble is that I've been on this too long and probably had too many energy drinks so am not concentrating properly, I can't figure out the way to pick out the nearest colour neighbor if the appropriate hex code doesn't exist. Any ideas on the perfect query? NB: I know pulling out the slices one by one is not ideal however the mosaic is only rebuilt periodically so a sudden burst in the mysql load doesn't really bother me, however if there us a way to pull the images out all at once that would also be a massive bonus.

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  • Remove appearance of TextField in droidText : Android

    - by AnujAroshA
    I am trying to create a PDF using droidText library. There I want to place some text content in the middle of the page but align to left. I was unable to do with Paragraph class and setAlignment() method. So I have decided to use TextField class. Below is the code I have used, Document document = new Document(PageSize.A4); try { PdfWriter writer = PdfWriter.getInstance(document, new FileOutputStream(android.os.Environment.getExternalStorageDirectory() + java.io.File.separator + "TextFields.pdf")); document.open(); TextField tf = new TextField(writer, new Rectangle(100, 300, 200, 350), "Content"); tf.setText("This is the content of text field"); tf.setAlignment(Element.ALIGN_CENTER); tf.setOptions(TextField.MULTILINE | TextField.REQUIRED); PdfFormField field = tf.getTextField(); writer.addAnnotation(field); } catch (DocumentException de) { System.err.println(de.getMessage()); } catch (IOException ioe) { System.err.println(ioe.getMessage()); } document.close(); Code works perfect, but the out put PDF file that I am getting has this TextField which can be editable and also change the font appearance when I am click on the TextField. I don't want that in to my final PDF. How can I remove that attribute? If it is not possible, is there any other way I can position some text in a PDF file using droidText library in Android?

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  • NETCF - Optimized Repaint (onPaint)

    - by Nullstr1ng
    Hi Guys, I want to ask for suggestions on how to optimize a repaint in Compact Framework? GetHashCode() didn't help because it always return a different hash code. Anyway, I have a program which you can drag and resize an object in run time. This object is a transparent object and it has a PNG image which also dynamically resize relative to object client size. Though I noticed, (e.g. I have 4 transparent object and I'm dragging or resizing one) all 4 of them triggers OnPaintBackground even if the 3 are not moving. Another one when am just tapping on the one object .. it sill triggers onPaintBacground(). Anyway, I don't have a problem when this events get triggered. What I like to do is optimization and that means I only have to repaint the object when it's necessary. Can you guys please give a suggestions? here's my pseudo C# code Bitmap _backBuff; onResize() { if(_backBuff != null) _backBuff.Dispose(); _backBuff = new Bitmap(ClientSize.Width, ClientSize.Height); Invalidate(); } onPaintBackground(e) /*have to use onPaintBackground because MSDN said it's faster*/ { using(Graphics g = Graphics.FromImage(_backBuff)) { g.Clear(Color.Black); // draw background ....some interface calling here ....and paint the background // draw alpha PNG .. get hDc .. paint PNG .. release hDc } e.Graphics.DrawImage(_backBuff,0,0); } Thanks in advance.

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