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Integrating Flickr with ASP.Net application

- by sreejukg

Flickr is the popular photo management and sharing application offered by yahoo. The services from flicker allow you to store and share photos and videos online. Flicker offers strong API support for almost all services they provide. Using this API, developers can integrate photos to their public website. Since 2005, developers have collaborated on top of Flickr's APIs to build fun, creative, and gorgeous experiences around photos that extend beyond Flickr. In this article I am going to demonstrate how easily you can bring the photos stored on flicker to your website. Let me explain the scenario this article is trying to address. I have a flicker account where I upload photos and share in many ways offered by Flickr. Now I have a public website, instead of re-upload the photos again to public website, I want to show this from Flickr. Also I need complete control over what photo to display. So I went and referred the Flickr documentation and there is API support ready to address my scenario (and more… ). FlickerAPI for ASP.Net To Integrate Flicker with ASP.Net applications, there is a library available in CodePlex. You can find it here http://flickrnet.codeplex.com/ Visit the URL and download the latest version. The download includes a Zip file, when you unzip you will get a number of dlls. Since I am going to use ASP.Net application, I need FlickrNet.dll. See the screenshot of all the dlls, and there is a help file available in the download (.chm) for your reference. Once you have the dll, you need to use Flickr API from your website. I assume you have a flicker account and you are familiar with Flicker services. Arrange your photos using Sets in Flickr In flicker, you can define sets and add your uploaded photos to sets. You can compare set to photo album. A set is a logical collection of photos, which is an excellent option for you to categorize your photos. Typically you will have a number of sets each set having few photos. You can write application that brings photos from sets to your website. For the purpose of this article I already created a set Flickr and added some photos to it. Once you logged in to Flickr, you can see the Sets under the Menu. In the Sets page, you will see all the sets you have created. As you notice, you can see certain sample images I have uploaded just to test the functionality. Though I wish I couldn’t create good photos so please bear with me. I have created 2 photo sets named Blue Album and Red Album. Click on the image for the set, will take you to the corresponding set page. In the set “Red Album” there are 4 photos and the set has a unique ID (highlighted in the URL). You can simply retrieve the photos with the set id from your application. In this article I am going to retrieve the images from Red album in my ASP.Net page. For that First I need to setup FlickrAPI for my usage. Configure Flickr API Key As I mentioned, we are going to use Flickr API to retrieve the photos stored in Flickr. In order to get access to Flickr API, you need an API key. To create an API key, navigate to the URL http://www.flickr.com/services/apps/create/ Click on Request an API key link, now you need to tell Flickr whether your application in commercial or non-commercial. I have selected a non-commercial key. Now you need to enter certain information about your application. Once you enter the details, Click on the submit button. Now Flickr will create the API key for your application. Generating non-commercial API key is very easy, in couple of steps the key will be generated and you can use the key in your application immediately. ASP.Net application for retrieving photos Now we need write an ASP.Net application that display pictures from Flickr. Create an empty web application (I named this as FlickerIntegration) and add a reference to FlickerNet.dll. Add a web form page to the application where you will retrieve and display photos(I have named this as Gallery.aspx). After doing all these, the solution explorer will look similar to following. I have used the below code in the Gallery.aspx page. The output for the above code is as follows. I am going to explain the code line by line here. First it is adding a reference to the FlickrNet namespace. using FlickrNet; Then create a Flickr object by using your API key. Flickr f = new Flickr("<yourAPIKey>"); Now when you retrieve photos, you can decide what all fields you need to retrieve from Flickr. Every photo in Flickr contains lots of information. Retrieving all will affect the performance. For the demonstration purpose, I have retrieved all the available fields as follows. PhotoSearchExtras.All But if you want to specify the fields you can use logical OR operator(|). For e.g. the following statement will retrieve owner name and date taken. PhotoSearchExtras extraInfo = PhotoSearchExtras.OwnerName | PhotoSearchExtras.DateTaken; Then retrieve all the photos from a photo set using PhotoSetsGetPhotos method. I have passed the PhotoSearchExtras object created earlier. PhotosetPhotoCollection photos = f.PhotosetsGetPhotos("72157629872940852", extraInfo); The PhotoSetsGetPhotos method will return a collection of Photo objects. You can just navigate through the collection using a foreach statement. foreach (Photo p in photos) { //access each photo properties } Photo class have lot of properties that map with the properties from Flickr. The chm documentation comes along with the CodePlex download is a great asset for you to understand the fields. In the above code I just used the following p.LargeUrl – retrieves the large image url for the photo. p.ThumbnailUrl – retrieves the thumbnail url for the photo p.Title – retrieves the Title of the photo p.DateUploaded – retrieves the date of upload Visual Studio intellisense will give you all properties, so it is easy, you can just try with Visual Studio intellisense to find the right properties you are looking for. Most of hem are self-explanatory. So you can try retrieving the required properties. In the above code, I just pushed the photos to the page. In real time you can use the retrieved photos along with JQuery libraries to create animated photo galleries, slideshows etc. Configuration and Troubleshooting If you get access denied error while executing the code, you need to disable the caching in Flickr API. FlickrNet cache the photos to your local disk when retrieved. You can specify a cache folder where the application need write permission. You can specify the Cache folder in the code as follows. Flickr.CacheLocation = Server.MapPath("./FlickerCache/"); If the application doesn’t have have write permission to the cache folder, the application will throw access denied error. If you cannot give write permission to the cache folder, then you must disable the caching. You can do this from code as follows. Flickr.CacheDisabled = true; Disabling cache will have an impact on the performance. Take care! Also you can define the Flickr settings in web.config file.You can find the documentation here. http://flickrnet.codeplex.com/wikipage?title=ExampleConfigFile&ProjectName=flickrnet Flickr is a great place for storing and sharing photos. The API access allows developers to do seamless integration with the photos uploaded on Flickr.

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Career development as a Software Developer without becoming a manager.

- by albertpascual

I’m a developer, I like to write new exciting code everyday, my perfect day at work is a day that when I wake up, I know that I have to write some code that I haven’t done before or to use a new framework/language/platform that is unknown to me. The best days in the office is when a project is waiting for me to architect or write. In my 15 years in the development field, I had to in order to get a better salary to manage people, not just to lead developers, to actually manage people. Something that I found out when I get into a management position is that I’m not that good at managing people, and not afraid to say it. I do not enjoy that part of the job, the worse one, takes time away from what I really like. Leading developers and managing people are very different things. I do like teaching and leading developers in a project. Yet most people believe, and is true in most companies, the way to get a better salary is to be promoted to a manager position. In order to advance in your career you need to let go of the everyday writing code and become a supervisor or manager. This is the path for developers after they become senior developers. As you get older and your family grows, the only way to hit your salary requirements is to advance your career to become a manager and get that manager salary. That path is the common in most companies, the most intelligent companies out there, have learned that promoting good developers mean getting a crappy manager and losing a good resource. Now scratch everything I said, because as I previously stated, I don’t see myself going to the office everyday and just managing people until is time to go home. I like to spend hours working in some code to accomplish a task, learning new platforms and languages or patterns to existing languages. Being interrupted every 15 minutes by emails or people stopping by my office to resolve their problems, is not something I could enjoy. All the sudden riding my motorcycle to work one cold morning over the Redlands Canyon and listening to .NET Rocks podcast, Michael “Doc” Norton explaining how to take control of your development career without necessary going to the manager’s track. I know, I should not have headphones under my helmet when riding a motorcycle in California. His conversation with Carl Franklin and Richard Campbell was just confirming everything I have ever did with actually more details and assuring that there are other paths. His method was simple yet most of us, already do many of those steps, Mr. Michael “Doc” Norton believe that it pays off on the long run, that finally companies prefer to pay higher salaries to those developers, yet I would actually think that many companies do not see developers that way, this is not true for bigger companies. However I do believe the value of those developers increase and most of the time, changing companies could increase their salary instead of staying in the same one. In short without even trying to get into the shadow of Mr. Norton and without following the steps in the order; you should love to learn new technologies, and then teach them to other geeks. I personally have learn many technologies and I haven’t stop doing that, I am a professor at UCR where I teach ASP.NET and Silverlight. Mr Norton continues that after than, you want to be involve in the development community, user groups, online forums, open source projects. I personally talk to user groups, I’m very active in forums asking and answering questions as well as for those I got awarded the Microsoft MVP for ASP.NET. After you accomplish all those, you should also expose yourself for what you know and what you do not know, learning a new language will make you humble again as well as extremely happy. There is no better feeling that learning a new language or pattern in your daily job. If you love your job everyday and what you do, I really recommend you to follow Michael’s presentation that he kindly share it on the link below. His confirmation is a refreshing, knowing that my future is not behind a desk where the computer screen is on my right hand side instead of in front of me. Where I don’t have to spent the days filling up performance forms for people and the new platforms that I haven’t been using yet are just at my fingertips. Presentation here. http://www.slideshare.net/LeanDog/take-control-of-your-development-career-michael-doc-norton?from=share_email_logout3 Take Control of Your Development Career Welcome! Michael “Doc” Norton @DocOnDev http://docondev.blogspot.com/ [email protected] Recovering Post Technical I love to learn I love to teach I love to work in teams I love to write code I really love to write code What about YOU? Do you love your job? Do you love your Employer? Do you love your Boss? What do you love? What do you really love? Take Control Take Control • Get Noticed • Get Together • Get Your Mojo • Get Naked • Get Schooled Get Noticed Get Noticed Know Your Business Get Noticed Get Noticed Understand Management Get Noticed Get Noticed Do Your Existing Job Get Noticed Get Noticed Make Yourself Expendable Get Together Get Together Join a User Group Get Together Help Run a User Group Get Together Start a User Group Get Your Mojo Get Your Mojo Kata Get Your Mojo Koans Get Your Mojo Breakable Toys Get Your Mojo Open Source Get Naked Get Naked Run with Group A Get Naked Do Something Different Get Naked Own Your Mistakes Get Naked Admit You Don’t Know Get Schooled Get Schooled Choose a Mentor Get Schooled Attend Conferences Get Schooled Teach a New Subject Get Started Read These (Again) Take Control of Your Development Career Thank You! Michael “Doc” Norton @DocOnDev http://docondev.blogspot.com/ [email protected] In a short summary, I recommend any developer to check his blog and more important his presentation, I haven’t been lucky enough to watch him live, I’m looking forward the day I have the opportunity. He is giving us hope in the future of developers, when I see some of my geek friends moving to position that in short years they begin to regret, I get more unsure of my future doing what I love. I would say that now is looking at the spectrum of companies that understand and appreciate developers. There are a few there, hopefully with time code sweat shops will start disappearing and being a developer will feed a family of 4. Cheers Al tweetmeme_url = 'http://weblogs.asp.net/albertpascual/archive/2010/12/07/career-development-as-a-software-developer-without-becoming-a-manager.aspx'; tweetmeme_source = 'alpascual';

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Trying to run my code and compiler seems to just close after it executes [migrated]

- by Shane

I am trying to run a program and the compiler seems to just crash right after it executes ... i have no build errors so i am wondering what the hell is going on ... I am a bit of a novice so all help would be appreciated =). I don't know if you might have time to scan through the code but this is what i have got : using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ConsoleApplication1 { public class Student { string Fname, Lname, Program ; int Sid ; // Inputting information for students public void InputStudentInfo () { Console.WriteLine ("Please enter your first name") ; Fname = Console.ReadLine() ; Console.WriteLine ("Please enter you last name") ; Lname = Console.ReadLine() ; Console.WriteLine ("Please enter you student ID#") ; Sid = int.Parse(Console.ReadLine()) ; Console.WriteLine ("Enter the Program that you are completeing") ; Program = Console.ReadLine() ; } // Printing information for students public void PrintStudentInfo () { Console.Write (" Your name is " + Fname) ; Console.Write(" " + Lname); Console.WriteLine (" Your student identification number is " + Sid) ; Console.WriteLine (" The program you are registered for is " + Program) ; } /* public void MenuInterface() { Console.WriteLine (" 1. Input Student information" ) ; Console.WriteLine (" 2. Input Course information" ) ; Console.WriteLine (" 3. Input Grade information" ) ; Console.WriteLine (" 4. Print Course information" ) ; Console.WriteLine (" 5. Print Student information" ) ; Console.WriteLine (" 6. Print Grade information" ) ; Console.WriteLine (" 7. Print Student information including Course they are registered in and the grade obtained for that course" ) ; Console.WriteLine (" 8. Print grade info of the course in which student has achieved the highest grade" ) ; Console.WriteLine (" 0. Exit") ; Console.WriteLine (" Please select a choice from 0-8") ; accode = Console.ReadLine(); } */ } public class Course { string course1, course2, course3 ; int Stuid ; // Inputting Course Information public void InputCourseInfo () { Console.WriteLine (" Please re-enter your identification number") ; Stuid = int.Parse(Console.ReadLine()) ; Console.WriteLine (" Enter the name of your first course") ; course1 = Console.ReadLine() ; Console.WriteLine (" Enter the name of your second course") ; course2 = Console.ReadLine() ; Console.WriteLine (" Enter the name of your third course") ; course3 = Console.ReadLine() ; } // Printing Course Information public void PrintCourseInfo () { Console.WriteLine (" Your ID # is " + Stuid) ; Console.Write (" The Courses you selected are " + course1) ; Console.Write("," + course2); Console.Write(" and " + course3); } } public class Grade : Course { int Studentid ; int [] hwgrade ; int [] cwgrade ; int [] midegrade ; int [] finalegrade ; int [] totalgrade ; string coursename ; public Grade ( string cname , int Studentident , int [] homework , int [] classwork , int [] midexam , int [] finalexam) { coursename = cname ; Studentid = Studentident ; hwgrade = homework ; cwgrade = classwork ; midegrade = midexam ; finalegrade = finalexam ; } public string coname { get { return coursename ; } set { coursename = value ; } } public int Studentidenty { get { return Studentid ; } set { Studentid = value ; } } public void InputGradeInfo() { Console.WriteLine (" Please enter your Student ID" ) ; grade.Studentidenty = Console.ReadLine() ; for ( int i = 0; i < 3; i++) { Console.Writeline (" Please enter the Course name" ) ; grade.coname[i] = Console.Readline() ; Console.Writeline (" Please enter your homework grade") ; grade.hwgrade[i] = int.parse(Console.Readline()) ; // ..... } } public void CalcTotalGrade() { for (int i = 0; i < 3; i++) { grade.courseper[i] = (grade.hwgrade[i] + grade.cwgrade[i]) / 2; grade.finalper[i] = (grade.midexam[i] + grade.finalegrade[i]) / 2; grade.totalgrade[i] = (grade.courseper[i] + finalper[i]) / 2; } } public void PrintGradeInfo() { for ( int i = 0; i < 3; i++) { Console.Writeline (" Your homework grade is" + grade.hwgrade[i]) ; // ..... } } static void Main(string[] args) { int accode ; Student student = new Student() ; Course course = new Course() ; Grade grade = new Grade() ; do { Console.WriteLine(" 1. Input Student information"); Console.WriteLine(" 2. Input Course information"); Console.WriteLine(" 3. Input Grade information"); Console.WriteLine(" 4. Print Course information"); Console.WriteLine(" 5. Print Student information"); Console.WriteLine(" 6. Print Grade information"); Console.WriteLine(" 7. Print Student information including Course they are registered in and the grade obtained for that course"); Console.WriteLine(" 8. Print grade info of the course in which student has achieved the highest grade"); Console.WriteLine(" 0. Exit"); Console.WriteLine(" Please select a choice from 0-8"); accode = Console.ReadLine(); switch (accode) { case 1: student.InputStudentInfo(); break; case 2: course.InputCourseInfo(); break; case 3: grade.InputGradeInfo(); break; case 4: course.PrintCourseInfo(); break; case 5: student.PRintStudentInfo(); break; case 6: grade.PrintGradeInfo(); break; case 0: Console.WriteLine(" You have chosen to exit the program have a good day. =)"); break; } } while (accode != 0); Console.ReadKey(); } } }

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Windows Azure Myths

- by BuckWoody

Windows Azure is part of the Microsoft "stack" - the suite of software and services we offer. Because we have so many products in almost every part of technology, it's hard to know everything about all parts of what we do - even for those of us who work here. So it's no surprise that some folks are not as familiar with Windows and SQL Azure as they are, say Windows Server or XBox. As I chat with folks about a solution for a business or organization need, I put Windows Azure into the mix. I always start off with "What do you already know about Windows Azure?" so that I don't bore folks with information they already have. I some cases they've checked out the product ahead of time and have specific questions, in others they aren't as familiar, and in still others there is a fair amount of mis-information. Sometimes that's because of a marketing failure, sometimes it's hearsay, and somtetimes it's active misinformation. I thought I might lay out a few of these misconceptions. As always - do your fact-checking! Never take anyone's word alone (including mine) as gospel. Make sure you educate yourself on your options. Your company or your clients depend on you to have the right information on IT, so make sure you live up to that. Myth 1: Nobody uses Windows Azure It's true that we don't give out numbers on the amount of clients on Windows and SQL Azure. But lots of folks are here - companies you may have heard of like Boeing, NASA, Fujitsu, The City of London, Nuedesic, and many others. I deal with firms small and large that use Windows Azure for mission-critical applications, sometimes totally on Windows and/or SQL Azure, sometimes in conjunction with an on-premises system, sometimes for only a specific component in Windows Azure like storage. The interesting thing is that many sites you visit have a Windows Azure component, or are running on Windows Azure. They just don't announce it. Just like the other cloud providers, the companies have asked to be completely branded themselves - they don't want you to be aware or care that they are on Windows Azure. Sometimes that's for security, other times it's for different reasons. It's just like the web sites you visit. For the most part, they don't advertise which OS or Web Server they use. It really just shouldn't matter. The point is that they just use what works to solve a given problem. Check out a few public case studies here: https://www.windowsazure.com/en-us/home/case-studies/ Myth 2: It's only for Microsoft stuff - can't use Open Source This is the one I face the most, and am the most dismayed by. We work just fine with many open source products, including Java, NodeJS, PHP, Ruby, Python, Hadoop, and many other languages and applications. You can quickly deploy a Wordpress, Umbraco and other "kits". We have software development kits (SDK's) for iPhones, iPads, Android, Windows phones and more. We have an SDK to work with FaceBook and other social networks. In short, we play well with others. More on the languages and runtimes we support here: https://www.windowsazure.com/en-us/develop/overview/ More on the SDK's here: http://www.wadewegner.com/2011/05/windows-azure-toolkit-for-ios/, http://www.wadewegner.com/2011/08/windows-azure-toolkits-for-devices-now-with-android/, http://azuretoolkit.codeplex.com/ Myth 3: Microsoft expects me to switch everything to "the cloud" No, we don't. That would be disasterous, unless the only things you run in your company uses works perfectly in Azure. Use Windows Azure - or any cloud for that matter - where it works. Whenever I talk to companies, I focus on two things: Something that is broken and needs to be re-architected Something you want to do that is new If something is broken, and you need new tools to scale, extend, add capacity dynamically and so on, then you can consider using Windows or SQL Azure. It can help solve problems that you have, or it may include a component you don't want to write or architect yourself. Sometimes you want to do something new, like extend your company's offerings to mobile phones, to the web, or to a social network. More info on where it works here: http://blogs.msdn.com/b/buckwoody/archive/2011/01/18/windows-azure-and-sql-azure-use-cases.aspx Myth 4: I have to write code to use Windows and SQL Azure If Windows Azure is a PaaS - a Platform as a Service - then don't you have to write code to use it? Nope. Windows and SQL Azure are made up of various components. Some of those components allow you to write and deploy code (like Compute) and others don't. We have lots of customers using Windows Azure storage as a backup, to securely share files instead of using DropBox, to distribute videos or code or firmware, and more. Others use our High Performance Computing (HPC) offering to rent a supercomputer when they need one. You can even throw workloads at that using Excel! In addition there are lots of other components in Windows Azure you can use, from the Windows Azure Media Services to others. More here: https://www.windowsazure.com/en-us/home/scenarios/saas/ Myth 5: Windows Azure is just another form of "vendor lock-in" Windows Azure uses .NET, OSS languages and standard interfaces for the code. Sure, you're not going to take the code line-for-line and run it on a mainframe, but it's standard code that you write, and can port to something else. And the data is yours - you can bring it back whever you want. It's either in text or binary form, that you have complete control over. There are no licenses - you can "pay as you go", and when you're done, you can leave the service and take all your code, data and IP with you. So go out there, read up, try it. Use it where it works. And don't believe everything you hear - sometimes the Internet doesn't get it all correct. :)

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Writing Unit Tests for an ASP.NET MVC Action Method that handles Ajax Request and Normal Request

- by shiju

In this blog post, I will demonstrate how to write unit tests for an ASP.NET MVC action method, which handles both Ajax request and normal HTTP Request. I will write a unit test for specifying the behavior of an Ajax request and will write another unit test for specifying the behavior of a normal HTTP request. Both Ajax request and normal request will be handled by a single action method. So the ASP.NET MVC action method will be execute HTTP Request object’s IsAjaxRequest method for identifying whether it is an Ajax request or not. So we have to create mock object for Request object and also have to make as a Ajax request from the unit test for verifying the behavior of an Ajax request. I have used NUnit and Moq for writing unit tests. Let me write a unit test for a Ajax request Code Snippet [Test] public void Index_AjaxRequest_Returns_Partial_With_Expense_List() { // Arrange Mock<HttpRequestBase> request = new Mock<HttpRequestBase>(); Mock<HttpResponseBase> response = new Mock<HttpResponseBase>(); Mock<HttpContextBase> context = new Mock<HttpContextBase>(); context.Setup(c => c.Request).Returns(request.Object); context.Setup(c => c.Response).Returns(response.Object); //Add XMLHttpRequest request header request.Setup(req => req["X-Requested-With"]). Returns("XMLHttpRequest"); IEnumerable<Expense> fakeExpenses = GetMockExpenses(); expenseRepository.Setup(x => x.GetMany(It. IsAny<Expression<Func<Expense, bool>>>())). Returns(fakeExpenses); ExpenseController controller = new ExpenseController( commandBus.Object, categoryRepository.Object, expenseRepository.Object); controller.ControllerContext = new ControllerContext( context.Object, new RouteData(), controller); // Act var result = controller.Index(null, null) as PartialViewResult; // Assert Assert.AreEqual("_ExpenseList", result.ViewName); Assert.IsNotNull(result, "View Result is null"); Assert.IsInstanceOf(typeof(IEnumerable<Expense>), result.ViewData.Model, "Wrong View Model"); var expenses = result.ViewData.Model as IEnumerable<Expense>; Assert.AreEqual(3, expenses.Count(), "Got wrong number of Categories"); } In the above unit test, we are calling Index action method of a controller named ExpenseController, which will returns a PartialView named _ExpenseList, if it is an Ajax request. We have created mock object for HTTPContextBase and setup XMLHttpRequest request header for Request object’s X-Requested-With for making it as a Ajax request. We have specified the ControllerContext property of the controller with mocked object HTTPContextBase. Code Snippet controller.ControllerContext = new ControllerContext( context.Object, new RouteData(), controller); Let me write a unit test for a normal HTTP method Code Snippet [Test] public void Index_NormalRequest_Returns_Index_With_Expense_List() { // Arrange Mock<HttpRequestBase> request = new Mock<HttpRequestBase>(); Mock<HttpResponseBase> response = new Mock<HttpResponseBase>(); Mock<HttpContextBase> context = new Mock<HttpContextBase>(); context.Setup(c => c.Request).Returns(request.Object); context.Setup(c => c.Response).Returns(response.Object); IEnumerable<Expense> fakeExpenses = GetMockExpenses(); expenseRepository.Setup(x => x.GetMany(It. IsAny<Expression<Func<Expense, bool>>>())). Returns(fakeExpenses); ExpenseController controller = new ExpenseController( commandBus.Object, categoryRepository.Object, expenseRepository.Object); controller.ControllerContext = new ControllerContext( context.Object, new RouteData(), controller); // Act var result = controller.Index(null, null) as ViewResult; // Assert Assert.AreEqual("Index", result.ViewName); Assert.IsNotNull(result, "View Result is null"); Assert.IsInstanceOf(typeof(IEnumerable<Expense>), result.ViewData.Model, "Wrong View Model"); var expenses = result.ViewData.Model as IEnumerable<Expense>; Assert.AreEqual(3, expenses.Count(), "Got wrong number of Categories"); } In the above unit test, we are not specifying the XMLHttpRequest request header for Request object’s X-Requested-With, so that it will be normal HTTP Request. If this is a normal request, the action method will return a ViewResult with a view template named Index. The below is the implementation of Index action method Code Snippet public ActionResult Index(DateTime? startDate, DateTime? endDate) { //If date is not passed, take current month's first and last date DateTime dtNow; dtNow = DateTime.Today; if (!startDate.HasValue) { startDate = new DateTime(dtNow.Year, dtNow.Month, 1); endDate = startDate.Value.AddMonths(1).AddDays(-1); } //take last date of start date's month, if end date is not passed if (startDate.HasValue && !endDate.HasValue) { endDate = (new DateTime(startDate.Value.Year, startDate.Value.Month, 1)).AddMonths(1).AddDays(-1); } var expenses = expenseRepository.GetMany( exp => exp.Date >= startDate && exp.Date <= endDate); //if request is Ajax will return partial view if (Request.IsAjaxRequest()) { return PartialView("_ExpenseList", expenses); } //set start date and end date to ViewBag dictionary ViewBag.StartDate = startDate.Value.ToShortDateString(); ViewBag.EndDate = endDate.Value.ToShortDateString(); //if request is not ajax return View("Index",expenses); } The index action method will returns a PartialView named _ExpenseList, if it is an Ajax request and will returns a View named Index if it is a normal request. Source Code The source code has been taken from my EFMVC app which can download from here

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Windows Azure Myths

- by BuckWoody

Windows Azure is part of the Microsoft "stack" - the suite of software and services we offer. Because we have so many products in almost every part of technology, it's hard to know everything about all parts of what we do - even for those of us who work here. So it's no surprise that some folks are not as familiar with Windows and SQL Azure as they are, say Windows Server or XBox. As I chat with folks about a solution for a business or organization need, I put Windows Azure into the mix. I always start off with "What do you already know about Windows Azure?" so that I don't bore folks with information they already have. I some cases they've checked out the product ahead of time and have specific questions, in others they aren't as familiar, and in still others there is a fair amount of mis-information. Sometimes that's because of a marketing failure, sometimes it's hearsay, and somtetimes it's active misinformation. I thought I might lay out a few of these misconceptions. As always - do your fact-checking! Never take anyone's word alone (including mine) as gospel. Make sure you educate yourself on your options. Your company or your clients depend on you to have the right information on IT, so make sure you live up to that. Myth 1: Nobody uses Windows Azure It's true that we don't give out numbers on the amount of clients on Windows and SQL Azure. But lots of folks are here - companies you may have heard of like Boeing, NASA, Fujitsu, The City of London, Nuedesic, and many others. I deal with firms small and large that use Windows Azure for mission-critical applications, sometimes totally on Windows and/or SQL Azure, sometimes in conjunction with an on-premises system, sometimes for only a specific component in Windows Azure like storage. The interesting thing is that many sites you visit have a Windows Azure component, or are running on Windows Azure. They just don't announce it. Just like the other cloud providers, the companies have asked to be completely branded themselves - they don't want you to be aware or care that they are on Windows Azure. Sometimes that's for security, other times it's for different reasons. It's just like the web sites you visit. For the most part, they don't advertise which OS or Web Server they use. It really just shouldn't matter. The point is that they just use what works to solve a given problem. Check out a few public case studies here: https://www.windowsazure.com/en-us/home/case-studies/ Myth 2: It's only for Microsoft stuff - can't use Open Source This is the one I face the most, and am the most dismayed by. We work just fine with many open source products, including Java, NodeJS, PHP, Ruby, Python, Hadoop, and many other languages and applications. You can quickly deploy a Wordpress, Umbraco and other "kits". We have software development kits (SDK's) for iPhones, iPads, Android, Windows phones and more. We have an SDK to work with FaceBook and other social networks. In short, we play well with others. More on the languages and runtimes we support here: https://www.windowsazure.com/en-us/develop/overview/ More on the SDK's here: http://www.wadewegner.com/2011/05/windows-azure-toolkit-for-ios/, http://www.wadewegner.com/2011/08/windows-azure-toolkits-for-devices-now-with-android/, http://azuretoolkit.codeplex.com/ Myth 3: Microsoft expects me to switch everything to "the cloud" No, we don't. That would be disasterous, unless the only things you run in your company uses works perfectly in Azure. Use Windows Azure - or any cloud for that matter - where it works. Whenever I talk to companies, I focus on two things: Something that is broken and needs to be re-architected Something you want to do that is new If something is broken, and you need new tools to scale, extend, add capacity dynamically and so on, then you can consider using Windows or SQL Azure. It can help solve problems that you have, or it may include a component you don't want to write or architect yourself. Sometimes you want to do something new, like extend your company's offerings to mobile phones, to the web, or to a social network. More info on where it works here: http://blogs.msdn.com/b/buckwoody/archive/2011/01/18/windows-azure-and-sql-azure-use-cases.aspx Myth 4: I have to write code to use Windows and SQL Azure If Windows Azure is a PaaS - a Platform as a Service - then don't you have to write code to use it? Nope. Windows and SQL Azure are made up of various components. Some of those components allow you to write and deploy code (like Compute) and others don't. We have lots of customers using Windows Azure storage as a backup, to securely share files instead of using DropBox, to distribute videos or code or firmware, and more. Others use our High Performance Computing (HPC) offering to rent a supercomputer when they need one. You can even throw workloads at that using Excel! In addition there are lots of other components in Windows Azure you can use, from the Windows Azure Media Services to others. More here: https://www.windowsazure.com/en-us/home/scenarios/saas/ Myth 5: Windows Azure is just another form of "vendor lock-in" Windows Azure uses .NET, OSS languages and standard interfaces for the code. Sure, you're not going to take the code line-for-line and run it on a mainframe, but it's standard code that you write, and can port to something else. And the data is yours - you can bring it back whever you want. It's either in text or binary form, that you have complete control over. There are no licenses - you can "pay as you go", and when you're done, you can leave the service and take all your code, data and IP with you. So go out there, read up, try it. Use it where it works. And don't believe everything you hear - sometimes the Internet doesn't get it all correct. :)

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Cost Comparison Hard Disk Drive to Solid State Drive on Price per Gigabyte - dispelling a myth!

- by tonyrogerson

It is often said that Hard Disk Drive storage is significantly cheaper per GiByte than Solid State Devices – this is wholly inaccurate within the database space. People need to look at the cost of the complete solution and not just a single component part in isolation to what is really required to meet the business requirement. Buying a single Hitachi Ultrastar 600GB 3.5” SAS 15Krpm hard disk drive will cost approximately £239.60 (http://scan.co.uk, 22nd March 2012) compared to an OCZ 600GB Z-Drive R4 CM84 PCIe costing £2,316.54 (http://scan.co.uk, 22nd March 2012); I’ve not included FusionIO ioDrive because there is no public pricing available for it – something I never understand and personally when companies do this I immediately think what are they hiding, luckily in FusionIO’s case the product is proven though is expensive compared to OCZ enterprise offerings. On the face of it the single 15Krpm hard disk has a price per GB of £0.39, the SSD £3.86; this is what you will see in the press and this is what sales people will use in comparing the two technologies – do not be fooled by this bullshit people! What is the requirement? The requirement is the database will have a static size of 400GB kept static through archiving so growth and trim will balance the database size, the client requires resilience, there will be several hundred call centre staff querying the database where queries will read a small amount of data but there will be no hot spot in the data so the randomness will come across the entire 400GB of the database, estimates predict that the IOps required will be approximately 4,000IOps at peak times, because it’s a call centre system the IO latency is important and must remain below 5ms per IO. The balance between read and write is 70% read, 30% write. The requirement is now defined and we have three of the most important pieces of the puzzle – space required, estimated IOps and maximum latency per IO. Something to consider with regard SQL Server; write activity requires synchronous IO to the storage media specifically the transaction log; that means the write thread will wait until the IO is completed and hardened off until the thread can continue execution, the requirement has stated that 30% of the system activity will be write so we can expect a high amount of synchronous activity. The hardware solution needs to be defined; two possible solutions: hard disk or solid state based; the real question now is how many hard disks are required to achieve the IO throughput, the latency and resilience, ditto for the solid state. Hard Drive solution On a test on an HP DL380, P410i controller using IOMeter against a single 15Krpm 146GB SAS drive, the throughput given on a transfer size of 8KiB against a 40GiB file on a freshly formatted disk where the partition is the only partition on the disk thus the 40GiB file is on the outer edge of the drive so more sectors can be read before head movement is required: For 100% sequential IO at a queue depth of 16 with 8 worker threads 43,537 IOps at an average latency of 2.93ms (340 MiB/s), for 100% random IO at the same queue depth and worker threads 3,733 IOps at an average latency of 34.06ms (34 MiB/s). The same test was done on the same disk but the test file was 130GiB: For 100% sequential IO at a queue depth of 16 with 8 worker threads 43,537 IOps at an average latency of 2.93ms (340 MiB/s), for 100% random IO at the same queue depth and worker threads 528 IOps at an average latency of 217.49ms (4 MiB/s). From the result it is clear random performance gets worse as the disk fills up – I’m currently writing an article on short stroking which will cover this in detail. Given the work load is random in nature looking at the random performance of the single drive when only 40 GiB of the 146 GB is used gives near the IOps required but the latency is way out. Luckily I have tested 6 x 15Krpm 146GB SAS 15Krpm drives in a RAID 0 using the same test methodology, for the same test above on a 130 GiB for each drive added the performance boost is near linear, for each drive added throughput goes up by 5 MiB/sec, IOps by 700 IOps and latency reducing nearly 50% per drive added (172 ms, 94 ms, 65 ms, 47 ms, 37 ms, 30 ms). This is because the same 130GiB is spread out more as you add drives 130 / 1, 130 / 2, 130 / 3 etc. so implicit short stroking is occurring because there is less file on each drive so less head movement required. The best latency is still 30 ms but we have the IOps required now, but that’s on a 130GiB file and not the 400GiB we need. Some reality check here: a) the drive randomness is more likely to be 50/50 and not a full 100% but the above has highlighted the effect randomness has on the drive and the more a drive fills with data the worse the effect. For argument sake let us assume that for the given workload we need 8 disks to do the job, for resilience reasons we will need 16 because we need to RAID 1+0 them in order to get the throughput and the resilience, RAID 5 would degrade performance. Cost for hard drives: 16 x £239.60 = £3,833.60 For the hard drives we will need disk controllers and a separate external disk array because the likelihood is that the server itself won’t take the drives, a quick spec off DELL for a PowerVault MD1220 which gives the dual pathing with 16 disks 146GB 15Krpm 2.5” disks is priced at £7,438.00, note its probably more once we had two controller cards to sit in the server in, racking etc. Minimum cost taking the DELL quote as an example is therefore: {Cost of Hardware} / {Storage Required} £7,438.60 / 400 = £18.595 per GB £18.59 per GiB is a far cry from the £0.39 we had been told by the salesman and the myth. Yes, the storage array is composed of 16 x 146 disks in RAID 10 (therefore 8 usable) giving an effective usable storage availability of 1168GB but the actual storage requirement is only 400 and the extra disks have had to be purchased to get the IOps up. Solid State Drive solution A single card significantly exceeds the IOps and latency required, for resilience two will be required. ( £2,316.54 * 2 ) / 400 = £11.58 per GB With the SSD solution only two PCIe sockets are required, no external disk units, no additional controllers, no redundant controllers etc. Conclusion I hope by showing you an example that the myth that hard disk drives are cheaper per GiB than Solid State has now been dispelled - £11.58 per GB for SSD compared to £18.59 for Hard Disk. I’ve not even touched on the running costs, compare the costs of running 18 hard disks, that’s a lot of heat and power compared to two PCIe cards!Just a quick note: I've left a fair amount of information out due to this being a blog! If in doubt, email me :)I'll also deal with the myth that SSD's wear out at a later date as well - that's just way over done still, yes, 5 years ago, but now - no.

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Thou shalt not put code on a piedestal - Code is a tool, no more, no less

- by Ralf Westphal

“Write great code and everything else becomes easier” is what Paul Pagel believes in. That´s his version of an adage by Brian Marick he cites: “treat code as an end, not just a means.” And he concludes: “My post-Agile world is software craftsmanship.” I wonder, if that´s really the way to go. Will “simply” writing great code lead the software industry into the light? He´s alluding to the philosopher Kant who proposed, a human beings should never be treated as a means, but always as an end. But should we transfer this ethical statement into the world of software? I doubt it. Reason #1: Human beings are categorially different from code. They are autonomous entities who need to find a way of living happily together. To Kant it seemed this goal could only be reached if nobody (ab)used a human being for his/her purposes. Because using a human being, i.e. treating it as a means, would contradict the fundamental autonomy and freedom of human beings. People should hold up a symmetric view of their relationships: Since nobody wants to be (ab)used, nobody should (ab)use anybody else. If you want to be treated decently, with respect, in accordance with your own free will - which means as an end - then do the same to other people. Code is dead, it´s a product, it´s a tool for people to reach their goals. No company spends any money on code other than to save money or earn money in the long run. Code is not a puppy. Enterprises do not commission software development to just feel good in its company. Code is not a buddy. Code is a slave, if you will. A mechanical slave, a non-tangible robot. Code is a tool, is a tool. And if we start to treat it differently, if we elevate its status unduely… I guess that will contort our relationship in a contraproductive way. Please get me right: Just because something is “just a tool”, “just a product” does not mean we should not be careful while designing, building, using it. Right to the contrary. We should be very careful when writing code – but not for the code´s sake! We should be careful because we respect our customers who are fellow human beings who should be treated as an end. If we are careless, neglectful, ignorant when producing code on their behalf, then we´re using them. Being sloppy means you´re caring more for yourself that for your customer. You´re then treating the customer as a means to fulfill some of your own needs. That´s plain unethical behavior. Reason #2: The focus should always be on your purpose, not on any tool. But if code is treated as an end, then the focus is on the code. That might sound right, because where else should be your focus as a software developer? But, well, I´d say, your focus should be on delivering value to your customer. Because in the end your customer does not care if you write a single line of code. She just wants her problem to be solved. Solving problems is the purpose of any contractor. Code must be treated just as a means, a tool we know how to handle very well. But if we´re really trying to be craftsmen then we should be conscious about exactly that and act ethically. That means we must never be so focused on our tool as to be unable to suggest better solutions to the problems of our customers than code. I´m all with Paul when he urges us to “Write great code”. Sure, if you need to write code, then by all means do so. Write the best code you can think of – and then try to improve it. Paul has all the best intentions when he signs Brians “treat code as an end” - but as we all know: “The road to hell is paved with best intentions” ;-) Yes, I can imagine a “hell of code focus”. In fact, I don´t need to imagine it, I´m seeing it quite often. Because code hell is whereever two developers stand together and are so immersed in talking about all sorts of coding tricks, design patterns, code smells, technologies, platforms, tools that they lose sight of the big picture. Talking about TDD or SOLID or refactoring is a sign of consciousness – relative to the “cowboy coders” view of the world. But from yet another point of view TDD, SOLID, and refactoring are just cures for ailments within a system. And I fear, if “Writing great code” is the only focus or the main focus of software development, then we as an industry lose the ability to see that. Focus draws a line around something, it defines a horizon for perceptions and thinking. So if we focus on code our horizon ends where “the land of code” ends. I don´t think that should be our professional attitude. So what about Software Craftsmanship as the next big thing after Agility? I think Software Craftsmanship has an important message for all software developers and beyond. But to make it the successor of the Agility movement seems to miss a point. Agility never claimed to solve all software development problems, I´d say. So to blame it for having missed out on certain aspects of it is wrong. If I had to summarize Agility in one word I´d say “Value”. Agility put value for the customer back in software development. Focus on delivering value early and often – that´s Agility´s mantra. All else follows from that. And I ask you: Is that obsolete? Is delivering value not hip anymore? No, sure not. That´s our very purpose as software developers. So how can Agility become obsolete and need to be replaced? We need to do away with this “either/or”-thinking. It´s either Agility or Lean or Software Craftsmanship or whatnot. Instead we should start integrating concepts and movements. Think “both/and”. Think Agility plus Software Craftsmanship plus Lean plus whatnot. We don´t neet to tear down anything from a piedestal and replace it with a new idol. Instead we should do away with piedestals and arrange whatever is helpful is a circle. Then we can turn to concepts, movements for whatever they are best. After 10 years of Agility we should be able to identify what it was good at – and keep that. Keep Agility around and add whatever Agility was lacking or never concerned with. Add whatever is at the core of Software Craftsmanship. Add whatever is at the core of Lean etc. But don´t call out the age of Post-Agility. Because it better never will end. Because once we start to lose Agility´s core we´re losing focus of the customer.

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Behavior Driven Development (BDD) and DevExpress XAF

- by Patrick Liekhus

So in my previous posts I showed you how I used EDMX to quickly build my business objects within XPO and XAF. But how do you test whether your business objects are actually doing what you want and verify that your business logic is correct? Well I was reading my monthly MSDN magazine last last year and came across an article about using SpecFlow and WatiN to build BDD tests. So why not use these same techniques to write SpecFlow style scripts and have them generate EasyTest scripts for use with XAF. Let me outline and show a few things below. I plan on releasing this code in a short while, I just wanted to preview what I was thinking. Before we begin… First, if you have not read the article in MSDN, here is the link to the article that I found my inspiration. It covers the overview of BDD vs. TDD, how to write some of the SpecFlow syntax and how use the “Steps” logic to create your own tests. Second, if you have not heard of EasyTest from DevExpress I strongly recommend you review it here. It basically takes the power of XAF and the beauty of your application and allows you to create text based files to execute automated commands within your application. Why would we do this? Because as you will see below, the cucumber syntax is easier for business analysts to interpret and digest the business rules from. You can find most of the information you will need on Cucumber syntax within The Secret Ninja Cucumber Scrolls located here. The basics of the syntax are that Given X When Y Then Z. For example, Given I am at the login screen When I enter my login credentials Then I expect to see the home screen. Pretty easy syntax to follow. Finally, we will need to download and install SpecFlow. You can find it on their website here. Once you have this installed then let’s write our first test. Let’s get started… So where to start. Create a new testing project within your solution. I typically call this with a similar naming convention as used by XAF, my project name .FunctionalTests (i.e. AlbumManager.FunctionalTests). Remove the basic test that is created for you. We will not use the default test but rather create our own SpecFlow “Feature” files. Add a new item to your project and select the SpecFlow Feature file under C#. Name your feature file as you do your class files after the test they are performing. Now you can crack open your new feature file and write the actual test. Make sure to have your Ninja Scrolls from above as it provides valuable resources on how to write your test syntax. In this test below you can see how I defined the documentation in the Feature section. This is strictly for our purposes of readability and do not effect the test. The next section is the Scenario Outline which is considered a test template. You can see the brackets <> around the fields that will be filled in for each test. So in the example below you can see that Given I am starting a new test and the application is open. This means I want a new EasyTest file and the windows application generated by XAF is open. Next When I am at the Albums screen tells XAF to navigate to the Albums list view. And I click the New:Album button, tells XAF to click the new button on the list grid. And I enter the following information tells XAF which fields to complete with the mapped values. And I click the Save and Close button causes the record to be saved and the detail form to be closed. Then I verify results tests the input data against what is visible in the grid to ensure that your record was created. The Scenarios section gives each test a unique name and then fills in the values for each test. This way you can use the same test to make multiple passes with different data. Almost there. Now we must save the feature file and the BDD tests will be written using standard unit test syntax. This is all handled for you by SpecFlow so just save the file. What you will see in your Test List Editor is a unit test for each of the above scenarios you just built. You can now use standard unit testing frameworks to execute the test as you desire. As you would expect then, these BDD SpecFlow tests can be automated into your build process to ensure that your business requirements are satisfied each and every time. How does it work? What we have done is to intercept the testing logic at runtime to interpret the SpecFlow syntax into EasyTest syntax. This is the basic StepDefinitions that we are working on now. We expect to put these on CodePlex within the next few days. You can always override and make your own rules as you see fit for your project. Follow the MSDN magazine above to start your own. You can see part of our implementation below. As you can gather from the MSDN article and the code sample below, we have created our own common rules to build the above syntax. The code implementation for these rules basically saves your information from the feature file into an EasyTest file format. It then executes the EasyTest file and parses the XML results of the test. If the test succeeds the test is passed. If the test fails, the EasyTest failure message is logged and the screen shot (as captured by EasyTest) is saved for your review. Again we are working on getting this code ready for mass consumption, but at this time it is not ready. We will post another message when it is ready with all details about usage and setup. Thanks

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Blogging locally and globally–my experience

- by DigiMortal

In Baltic MVP Summit 2011 there was discussion about having two blogs - one for local and another for global audience – and how to publish once written information in these blogs. There are many ways how to optimize your blogging activities if you have more than one audience and here you can find my experiences, best practices and advices about this topic. My two blogs I have to working blogs: this one here technology and programming blog for local market My local blog is almost five years old and it makes it one of the oldest company blogs in Estonia. It is still active and I write there as much as I have time for it. This blog here is active since September 2007, so it is about 3.5 years old right now. Both of these blogs are my major hits in my MVP carrier and they have very good web statistics too. My local blog My local blog is about programming, web and technology. It has way wider target audience then this blog here has. By example, in my local blog I blog also about local events, cool new concept phones, different webs providing some interesting services etc. But local guys can find there also my postings about how to solve one or another programming problem and postings about Microsoft technologies I am playing with. This far my local blog has a lot of readers for such a small country that Estonia is. This blog has made me a lot of cool contacts and I have had there a lot of interesting discussions about different technical topics. Why I started this blog? Living in small country is different than living in big country. In small country you have less people and therefore smaller audience so you have to target more than one technical topic to find enough readers. In a same time you are still interested in your main topics and you want to reach to more people who are sharing same interests with you. Practically one day y will grow out from local market and you go global. This is how this blog was born. Was it worth to create, promote and mess with it? Every second I have put on my time to this blog has been worth of it. Thanks to this blog I have found new good friends and without them I think it is more boring to work on different problems and solutions. Defining target audiences One thing you should always do when having more than one blog is defining target audiences. If you are just technomaniac interested in sharing your stuff and make some new friends and have something to write to your MVP nomination form then you don’t have to go through complex targeting process. You can do it simple way and same effectively. Here is how I defined target audiences to my blogs: local blog – reader of my local blog is IT professional, software developer, technology innovator or just some guy who is interested in technology, this blog – reader of this blog is experienced professional software developer who works on Microsoft technologies or software developer who is open minded and open to new technologies and interesting solutions to development problems. You can see how local blog – due to small market with less people – has wider definition for audience while this blog is heavily targeted to Microsoft technologies and specially to software development. On practical side these decisions are also made well I think because it is very hard to build up popular common IT blog. On global level it is better to target some specific niche and find readers who are professionals on your favorite topics. Thanks to this blog I have found new friends who are professional developers and I am very happy about all the discussions I have had with them. Publishing content to different blogs My local blog and this blog have some overlapping topics like .NET, databases and SEO. Due to this overlapping there is question: when I write posting to my local blog then should I have to publish same thing in my global blog? And if I write something to my global blog then should I publish same thing also in my local blog? Well, it really depends on the definition of your target audiences. If they match then of course it is good idea to translate you post and publish it also to another blog. But if you have different audiences then you may need to modify your posting before publishing it. The questions you have to answer are: is target audience interested in this topic? is target audience expecting more specific and deeper handling of this topic or are they expecting more general handling of topic? is the problem you are discussing actual for target audience or not? You have to answer these questions and after that make your decision. If you need to modify your original posting then take some time and do it. Provide quality to all your readers because they will respect you if you respect them. Cross-posting and referencing It is tempting to save time that preparing some blog post takes and if you have are done with posting in one blog it may seem like good idea to make short posting to another blog and add reference to first one where topic is discussed longer. Well, don’t do it – all your readers expect good quality content from you and jumping from one blog post to another is disturbing for them. Of course, there is problem with differences between target audiences. You may have wider target audience and some people may be interested in more specific handling of topic. In this case feel free to refer your blog you are writing in english. This is not working very well in opposite direction because almost all my global blog readers understand english but not estonian. By example, estonian language is complex one and online translating tools make very poor translations from estonian language. This is why I don’t even plan to publish postings here that refer to my local blog for more information. I am keeping these two blogs as two different worlds and if there is posting that fits well to both blogs I will write my posting to one blog and then answer previous three questions before posting same thing to another blog. Conclusion Growing out of your local market is not anything mysterious if you are living in small country. As it is harder to find people there who are interested in same topics with you then sooner or later you will start finding these new contacts from global audience. Global audience is bigger and to be visible there you must provide high quality content to your audience. It is something you will learn over time and you will learn every day something new when you are posting to your global blog. You may ask: if global blog is much more complex thing to do then is it worth to do at all? My answer is: yes, do it for sure. It is not easy thing to do when you start but if you work on your global blog and improve it over time you will get over all obstacles pretty soon. Just don’t forget one thing – content is king and your readers expect high quality from you.

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Steganography : Encoded audio and video file not being played, getting corrupted. What is the issue

- by Shantanu Gupta

I have made a steganography program to encrypt/Decrypt some text under image audio and video. I used image as bmp(54 byte header) file, audio as wav(44 byte header) file and video as avi(56 byte header) file formats. When I tries to encrypt text under all these file then it gets encrypted successfully and are also getting decrypted correctly. But it is creating a problem with audio and video i.e these files are not being played after encrypted result. What can be the problem. I am working on Turbo C++ compiler. I know it is super outdated compiler but I have to do it in this only. Here is my code to encrypt. int Binary_encode(char *txtSourceFileName, char *binarySourceFileName, char *binaryTargetFileName,const short headerSize) { long BinarySourceSize=0,TextSourceSize=0; char *Buffer; long BlockSize=10240, i=0; ifstream ReadTxt, ReadBinary; //reads ReadTxt.open(txtSourceFileName,ios::binary|ios::in);//file name, mode of open, here input mode i.e. read only if(!ReadTxt) { cprintf("\nFile can not be opened."); return 0; } ReadBinary.open(binarySourceFileName,ios::binary|ios::in);//file name, mode of open, here input mode i.e. read only if(!ReadBinary) { ReadTxt.close();//closing opened file cprintf("\nFile can not be opened."); return 0; } ReadBinary.seekg(0,ios::end);//setting pointer to a file at the end of file. ReadTxt.seekg(0,ios::end); BinarySourceSize=(long )ReadBinary.tellg(); //returns the position of pointer TextSourceSize=(long )ReadTxt.tellg(); //returns the position of pointer ReadBinary.seekg(0,ios::beg); //sets the pointer to the begining of file ReadTxt.seekg(0,ios::beg); //sets the pointer to the begining of file if(BinarySourceSize<TextSourceSize*50) //Minimum size of an image should be 50 times the size of file to be encrypted { cout<<"\n\n"; cprintf("Binary File size should be bigger than text file size."); ReadBinary.close(); ReadTxt.close(); return 0; } cout<<"\n"; cprintf("\n\nSize of Source Image/Audio File is : "); cout<<(float)BinarySourceSize/1024; cprintf("KB"); cout<<"\n"; cprintf("Size of Text File is "); cout<<TextSourceSize; cprintf(" Bytes"); cout<<"\n"; getch(); //write header to file without changing else file will not open //bmp image's header size is 53 bytes Buffer=new char[headerSize]; ofstream WriteBinary; // writes to file WriteBinary.open(binaryTargetFileName,ios::binary|ios::out|ios::trunc);//file will be created or truncated if already exists ReadBinary.read(Buffer,headerSize);//reads no of bytes and stores them into mem, size contains no of bytes in a file WriteBinary.write(Buffer,headerSize);//writes header to 2nd image delete[] Buffer;//deallocate memory /* Buffer = new char[sizeof(long)]; Buffer = (char *)(&TextSourceSize); cout<<Buffer; */ WriteBinary.write((char *)(&TextSourceSize),sizeof(long)); //writes no of byte to be written in image immediate after header ends //to decrypt file if(!(Buffer=new char[TextSourceSize])) { cprintf("Enough Memory could not be assigned."); return 0; } ReadTxt.read(Buffer,TextSourceSize);//read all data from text file ReadTxt.close();//file no more needed WriteBinary.write(Buffer,TextSourceSize);//writes all text file data into image delete[] Buffer;//deallocate memory //replace Tsize+1 below with Tsize and run the program to see the change //this is due to the reason that 50-54 byte no are of colors which we will be changing ReadBinary.seekg(TextSourceSize+1,ios::cur);//move pointer to the location-current loc i.e. 53+content of text file //write remaining image content to image file while(i<BinarySourceSize-headerSize-TextSourceSize+1) { i=i+BlockSize; Buffer=new char[BlockSize]; ReadBinary.read(Buffer,BlockSize);//reads no of bytes and stores them into mem, size contains no of bytes in a file WriteBinary.write(Buffer,BlockSize); delete[] Buffer; //clear memory, else program can fail giving correct output } ReadBinary.close(); WriteBinary.close(); //Encoding Completed return 0; } Code to decrypt int Binary_decode(char *binarySourceFileName, char *txtTargetFileName, const short headerSize) { long TextDestinationSize=0; char *Buffer; long BlockSize=10240; ifstream ReadBinary; ofstream WriteText; ReadBinary.open(binarySourceFileName,ios::binary|ios::in);//file will be appended if(!ReadBinary) { cprintf("File can not be opened"); return 0; } ReadBinary.seekg(headerSize,ios::beg); Buffer=new char[4]; ReadBinary.read(Buffer,4); TextDestinationSize=*((long *)Buffer); delete[] Buffer; cout<<"\n\n"; cprintf("Size of the File that will be created is : "); cout<<TextDestinationSize; cprintf(" Bytes"); cout<<"\n\n"; sleep(1); WriteText.open(txtTargetFileName,ios::binary|ios::out|ios::trunc);//file will be created if not exists else truncate its data while(TextDestinationSize>0) { if(TextDestinationSize<BlockSize) BlockSize=TextDestinationSize; Buffer= new char[BlockSize]; ReadBinary.read(Buffer,BlockSize); WriteText.write(Buffer,BlockSize); delete[] Buffer; TextDestinationSize=TextDestinationSize-BlockSize; } ReadBinary.close(); WriteText.close(); return 0; } int text_encode(char *SourcefileName, char *DestinationfileName) { ifstream fr; //reads ofstream fw; // writes to file char c; int random; clrscr(); fr.open(SourcefileName,ios::binary);//file name, mode of open, here input mode i.e. read only if(!fr) { cprintf("File can not be opened."); getch(); return 0; } fw.open(DestinationfileName,ios::binary|ios::out|ios::trunc);//file will be created or truncated if already exists while(fr) { int i; while(fr!=0) { fr.get(c); //reads a character from file and increments its pointer char ch; ch=c; ch=ch+1; fw<<ch; //appends character in c to a file } } fr.close(); fw.close(); return 0; } int text_decode(char *SourcefileName, char *DestinationName) { ifstream fr; //reads ofstream fw; // wrrites to file char c; int random; clrscr(); fr.open(SourcefileName,ios::binary);//file name, mode of open, here input mode i.e. read only if(!fr) { cprintf("File can not be opened."); return 0; } fw.open(DestinationName,ios::binary|ios::out|ios::trunc);//file will be created or truncated if already exists while(fr) { int i; while(fr!=0) { fr.get(c); //reads a character from file and increments its pointer char ch; ch=c; ch=ch-1; fw<<ch; //appends character in c to a file } } fr.close(); fw.close(); return 0; }

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Strange problem with Random Access Filing in C++

- by sam

This is a simple random access filing program . The problem arises where i want to write data randomly. If I write any where in the file the previous records are set to 0. the last 1 which is being entered currently holds the correct value all others =0. This is the code #include <iostream> #include<fstream> #include<string> using namespace std; class name { int id; int pass; public: void writeBlank(); void writedata(); void readdata(); void readall(); int getid() { return id; } int getpass() { return pass; } void setid(int i) { id=i; } void setpass(int p) { pass=p; } }; void name::writeBlank() { name person; person.setid(0); person.setpass(0); int i; ofstream out("pass.txt",ios::binary); if ( !out ) { cout << "File could not be opened." << endl; } for(i=0;i<10;i++) //make 10 records { cout<<"Put pointer is at: "<<out.tellp()<<endl; cout<<"Blank record "<<i<<" is: "<<person.getid()<<" "<<person.getpass()<<" and size: "<<sizeof(person)<<endl; cout<<"Put pointer is at: "<<out.tellp()<<endl; out.write(reinterpret_cast< const char * >(&person),sizeof(name)); } } void name::writedata() { ofstream out("pass.txt",ios::binary|ios::out); name n1; int iD,p; cout<<"ID?"; cin>>iD; n1.setid(iD); cout<<"Enter password"; cin>>p; n1.setpass(p); if (!out ) { cout << "File could not be opened." << endl; } out.seekp((n1.getid()-1)*sizeof(name),ios::beg); //pointer moves to desired location where we have to store password according to its ID(index) cout<<"File pointer is at: "<<out.tellp()<<endl; out.write(reinterpret_cast<const char*> (&n1), sizeof(name)); //write on that pointed location } void name::readall() { name n1; ifstream in("pass.txt",ios::binary); if ( !in ) { cout << "File could not be opened." << endl; } in.read( reinterpret_cast<char *>(&n1), sizeof(name) ); while ( !in.eof() ) { // display record cout<<endl<<"password at this index is:"<<n1.getpass()<<endl; cout<<"File pointer is at: "<<in.tellg()<<endl; // read next from file in.read( reinterpret_cast< char * >(&n1), sizeof(name)); } // end while } void name::readdata() { ifstream in("pass.txt",ios::binary); if ( !in ) { cout << "File could not be opened." << endl; } in.seekg((getid()-1)*sizeof(name)); //pointer moves to desired location where we have to read password according to its ID(index) cout<<"File pointer is at: "<<in.tellg()<<endl; in.read((char* )this,sizeof(name)); //reads from that pointed location cout<<endl<<"password at this index is:"<<getpass()<<endl; } int main() { name n1; cout<<"Enter 0 to write blank records"<<endl; cout<<"Enter 1 for new account"<<endl; cout<<"Enter 2 to login"<<endl; cout<<"Enter 3 to read all"<<endl; cout<<"Enter 9 to exit"<<endl; int option; cin>>option; while(option==0 || option==1 || option==2 || option==3) { if (option == 0) n1.writeBlank(); if(option==1) { /*int iD,p; cout<<"ID?"; cin>>iD; n1.setid(iD); cout<<"Enter password"; cin>>p; n1.setpass(p);*/ n1.writedata(); } int ind; if(option==2) { cout<<"Index?"; cin>>ind; n1.setid(ind); n1.readdata(); } if(option == 3) n1.readall(); cout<<"Enter 0 to write blank records"<<endl; cout<<"Enter 1 for new account"<<endl; cout<<"Enter 2 to login"<<endl; cout<<"Enter 3 to read all"<<endl; cout<<"Enter 9 to exit"<<endl; cin>>option; } } I Cant understand Y the previous records turn 0.

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What's up with OCFS2?

- by wcoekaer

On Linux there are many filesystem choices and even from Oracle we provide a number of filesystems, all with their own advantages and use cases. Customers often confuse ACFS with OCFS or OCFS2 which then causes assumptions to be made such as one replacing the other etc... I thought it would be good to write up a summary of how OCFS2 got to where it is, what we're up to still, how it is different from other options and how this really is a cool native Linux cluster filesystem that we worked on for many years and is still widely used. Work on a cluster filesystem at Oracle started many years ago, in the early 2000's when the Oracle Database Cluster development team wrote a cluster filesystem for Windows that was primarily focused on providing an alternative to raw disk devices and help customers with the deployment of Oracle Real Application Cluster (RAC). Oracle RAC is a cluster technology that lets us make a cluster of Oracle Database servers look like one big database. The RDBMS runs on many nodes and they all work on the same data. It's a Shared Disk database design. There are many advantages doing this but I will not go into detail as that is not the purpose of my write up. Suffice it to say that Oracle RAC expects all the database data to be visible in a consistent, coherent way, across all the nodes in the cluster. To do that, there were/are a few options : 1) use raw disk devices that are shared, through SCSI, FC, or iSCSI 2) use a network filesystem (NFS) 3) use a cluster filesystem(CFS) which basically gives you a filesystem that's coherent across all nodes using shared disks. It is sort of (but not quite) combining option 1 and 2 except that you don't do network access to the files, the files are effectively locally visible as if it was a local filesystem. So OCFS (Oracle Cluster FileSystem) on Windows was born. Since Linux was becoming a very important and popular platform, we decided that we would also make this available on Linux and thus the porting of OCFS/Windows started. The first version of OCFS was really primarily focused on replacing the use of Raw devices with a simple filesystem that lets you create files and provide direct IO to these files to get basically native raw disk performance. The filesystem was not designed to be fully POSIX compliant and it did not have any where near good/decent performance for regular file create/delete/access operations. Cache coherency was easy since it was basically always direct IO down to the disk device and this ensured that any time one issues a write() command it would go directly down to the disk, and not return until the write() was completed. Same for read() any sort of read from a datafile would be a read() operation that went all the way to disk and return. We did not cache any data when it came down to Oracle data files. So while OCFS worked well for that, since it did not have much of a normal filesystem feel, it was not something that could be submitted to the kernel mail list for inclusion into Linux as another native linux filesystem (setting aside the Windows porting code ...) it did its job well, it was very easy to configure, node membership was simple, locking was disk based (so very slow but it existed), you could create regular files and do regular filesystem operations to a certain extend but anything that was not database data file related was just not very useful in general. Logfiles ok, standard filesystem use, not so much. Up to this point, all the work was done, at Oracle, by Oracle developers. Once OCFS (1) was out for a while and there was a lot of use in the database RAC world, many customers wanted to do more and were asking for features that you'd expect in a normal native filesystem, a real "general purposes cluster filesystem". So the team sat down and basically started from scratch to implement what's now known as OCFS2 (Oracle Cluster FileSystem release 2). Some basic criteria were : Design it with a real Distributed Lock Manager and use the network for lock negotiation instead of the disk Make it a Linux native filesystem instead of a native shim layer and a portable core Support standard Posix compliancy and be fully cache coherent with all operations Support all the filesystem features Linux offers (ACL, extended Attributes, quotas, sparse files,...) Be modern, support large files, 32/64bit, journaling, data ordered journaling, endian neutral, we can mount on both endian /cross architecture,.. Needless to say, this was a huge development effort that took many years to complete. A few big milestones happened along the way... OCFS2 was development in the open, we did not have a private tree that we worked on without external code review from the Linux Filesystem maintainers, great folks like Christopher Hellwig reviewed the code regularly to make sure we were not doing anything out of line, we submitted the code for review on lkml a number of times to see if we were getting close for it to be included into the mainline kernel. Using this development model is standard practice for anyone that wants to write code that goes into the kernel and having any chance of doing so without a complete rewrite or.. shall I say flamefest when submitted. It saved us a tremendous amount of time by not having to re-fit code for it to be in a Linus acceptable state. Some other filesystems that were trying to get into the kernel that didn't follow an open development model had a lot harder time and a lot harsher criticism. March 2006, when Linus released 2.6.16, OCFS2 officially became part of the mainline kernel, it was accepted a little earlier in the release candidates but in 2.6.16. OCFS2 became officially part of the mainline Linux kernel tree as one of the many filesystems. It was the first cluster filesystem to make it into the kernel tree. Our hope was that it would then end up getting picked up by the distribution vendors to make it easy for everyone to have access to a CFS. Today the source code for OCFS2 is approximately 85000 lines of code. We made OCFS2 production with full support for customers that ran Oracle database on Linux, no extra or separate support contract needed. OCFS2 1.0.0 started being built for RHEL4 for x86, x86-64, ppc, s390x and ia64. For RHEL5 starting with OCFS2 1.2. SuSE was very interested in high availability and clustering and decided to build and include OCFS2 with SLES9 for their customers and was, next to Oracle, the main contributor to the filesystem for both new features and bug fixes. Source code was always available even prior to inclusion into mainline and as of 2.6.16, source code was just part of a Linux kernel download from kernel.org, which it still is, today. So the latest OCFS2 code is always the upstream mainline Linux kernel. OCFS2 is the cluster filesystem used in Oracle VM 2 and Oracle VM 3 as the virtual disk repository filesystem. Since the filesystem is in the Linux kernel it's released under the GPL v2 The release model has always been that new feature development happened in the mainline kernel and we then built consistent, well tested, snapshots that had versions, 1.2, 1.4, 1.6, 1.8. But these releases were effectively just snapshots in time that were tested for stability and release quality. OCFS2 is very easy to use, there's a simple text file that contains the node information (hostname, node number, cluster name) and a file that contains the cluster heartbeat timeouts. It is very small, and very efficient. As Sunil Mushran wrote in the manual : OCFS2 is an efficient, easily configured, quickly installed, fully integrated and compatible, feature-rich, architecture and endian neutral, cache coherent, ordered data journaling, POSIX-compliant, shared disk cluster file system. Here is a list of some of the important features that are included : Variable Block and Cluster sizes Supports block sizes ranging from 512 bytes to 4 KB and cluster sizes ranging from 4 KB to 1 MB (increments in power of 2). Extent-based Allocations Tracks the allocated space in ranges of clusters making it especially efficient for storing very large files. Optimized Allocations Supports sparse files, inline-data, unwritten extents, hole punching and allocation reservation for higher performance and efficient storage. File Cloning/snapshots REFLINK is a feature which introduces copy-on-write clones of files in a cluster coherent way. Indexed Directories Allows efficient access to millions of objects in a directory. Metadata Checksums Detects silent corruption in inodes and directories. Extended Attributes Supports attaching an unlimited number of name:value pairs to the file system objects like regular files, directories, symbolic links, etc. Advanced Security Supports POSIX ACLs and SELinux in addition to the traditional file access permission model. Quotas Supports user and group quotas. Journaling Supports both ordered and writeback data journaling modes to provide file system consistency in the event of power failure or system crash. Endian and Architecture neutral Supports a cluster of nodes with mixed architectures. Allows concurrent mounts on nodes running 32-bit and 64-bit, little-endian (x86, x86_64, ia64) and big-endian (ppc64) architectures. In-built Cluster-stack with DLM Includes an easy to configure, in-kernel cluster-stack with a distributed lock manager. Buffered, Direct, Asynchronous, Splice and Memory Mapped I/Os Supports all modes of I/Os for maximum flexibility and performance. Comprehensive Tools Support Provides a familiar EXT3-style tool-set that uses similar parameters for ease-of-use. The filesystem was distributed for Linux distributions in separate RPM form and this had to be built for every single kernel errata release or every updated kernel provided by the vendor. We provided builds from Oracle for Oracle Linux and all kernels released by Oracle and for Red Hat Enterprise Linux. SuSE provided the modules directly for every kernel they shipped. With the introduction of the Unbreakable Enterprise Kernel for Oracle Linux and our interest in reducing the overhead of building filesystem modules for every minor release, we decide to make OCFS2 available as part of UEK. There was no more need for separate kernel modules, everything was built-in and a kernel upgrade automatically updated the filesystem, as it should. UEK allowed us to not having to backport new upstream filesystem code into an older kernel version, backporting features into older versions introduces risk and requires extra testing because the code is basically partially rewritten. The UEK model works really well for continuing to provide OCFS2 without that extra overhead. Because the RHEL kernel did not contain OCFS2 as a kernel module (it is in the source tree but it is not built by the vendor in kernel module form) we stopped adding the extra packages to Oracle Linux and its RHEL compatible kernel and for RHEL. Oracle Linux customers/users obviously get OCFS2 included as part of the Unbreakable Enterprise Kernel, SuSE customers get it by SuSE distributed with SLES and Red Hat can decide to distribute OCFS2 to their customers if they chose to as it's just a matter of compiling the module and making it available. OCFS2 today, in the mainline kernel is pretty much feature complete in terms of integration with every filesystem feature Linux offers and it is still actively maintained with Joel Becker being the primary maintainer. Since we use OCFS2 as part of Oracle VM, we continue to look at interesting new functionality to add, REFLINK was a good example, and as such we continue to enhance the filesystem where it makes sense. Bugfixes and any sort of code that goes into the mainline Linux kernel that affects filesystems, automatically also modifies OCFS2 so it's in kernel, actively maintained but not a lot of new development happening at this time. We continue to fully support OCFS2 as part of Oracle Linux and the Unbreakable Enterprise Kernel and other vendors make their own decisions on support as it's really a Linux cluster filesystem now more than something that we provide to customers. It really just is part of Linux like EXT3 or BTRFS etc, the OS distribution vendors decide. Do not confuse OCFS2 with ACFS (ASM cluster Filesystem) also known as Oracle Cloud Filesystem. ACFS is a filesystem that's provided by Oracle on various OS platforms and really integrates into Oracle ASM (Automatic Storage Management). It's a very powerful Cluster Filesystem but it's not distributed as part of the Operating System, it's distributed with the Oracle Database product and installs with and lives inside Oracle ASM. ACFS obviously is fully supported on Linux (Oracle Linux, Red Hat Enterprise Linux) but OCFS2 independently as a native Linux filesystem is also, and continues to also be supported. ACFS is very much tied into the Oracle RDBMS, OCFS2 is just a standard native Linux filesystem with no ties into Oracle products. Customers running the Oracle database and ASM really should consider using ACFS as it also provides storage/clustered volume management. Customers wanting to use a simple, easy to use generic Linux cluster filesystem should consider using OCFS2. To learn more about OCFS2 in detail, you can find good documentation on http://oss.oracle.com/projects/ocfs2 in the Documentation area, or get the latest mainline kernel from http://kernel.org and read the source. One final, unrelated note - since I am not always able to publicly answer or respond to comments, I do not want to selectively publish comments from readers. Sometimes I forget to publish comments, sometime I publish them and sometimes I would publish them but if for some reason I cannot publicly comment on them, it becomes a very one-sided stream. So for now I am going to not publish comments from anyone, to be fair to all sides. You are always welcome to email me and I will do my best to respond to technical questions, questions about strategy or direction are sometimes not possible to answer for obvious reasons.

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Creating ASP.NET MVC Negotiated Content Results

- by Rick Strahl

In a recent ASP.NET MVC application I’m involved with, we had a late in the process request to handle Content Negotiation: Returning output based on the HTTP Accept header of the incoming HTTP request. This is standard behavior in ASP.NET Web API but ASP.NET MVC doesn’t support this functionality directly out of the box. Another reason this came up in discussion is last week’s announcements of ASP.NET vNext, which seems to indicate that ASP.NET Web API is not going to be ported to the cloud version of vNext, but rather be replaced by a combined version of MVC and Web API. While it’s not clear what new API features will show up in this new framework, it’s pretty clear that the ASP.NET MVC style syntax will be the new standard for all the new combined HTTP processing framework. Why negotiated Content? Content negotiation is one of the key features of Web API even though it’s such a relatively simple thing. But it’s also something that’s missing in MVC and once you get used to automatically having your content returned based on Accept headers it’s hard to go back to manually having to create separate methods for different output types as you’ve had to with Microsoft server technologies all along (yes, yes I know other frameworks – including my own – have done this for years but for in the box features this is relatively new from Web API). As a quick review, Accept Header content negotiation works off the request’s HTTP Accept header:POST http://localhost/mydailydosha/Editable/NegotiateContent HTTP/1.1 Content-Type: application/json Accept: application/json Host: localhost Content-Length: 76 Pragma: no-cache { ElementId: "header", PageName: "TestPage", Text: "This is a nice header" } If I make this request I would expect to get back a JSON result based on my application/json Accept header. To request XML I‘d just change the accept header:Accept: text/xml and now I’d expect the response to come back as XML. Now this only works with media types that the server can process. In my case here I need to handle JSON, XML, HTML (using Views) and Plain Text. HTML results might need more than just a data return – you also probably need to specify a View to render the data into either by specifying the view explicitly or by using some sort of convention that can automatically locate a view to match. Today ASP.NET MVC doesn’t support this sort of automatic content switching out of the box. Unfortunately, in my application scenario we have an application that started out primarily with an AJAX backend that was implemented with JSON only. So there are lots of JSON results like this:[Route("Customers")] public ActionResult GetCustomers() { return Json(repo.GetCustomers(),JsonRequestBehavior.AllowGet); } These work fine, but they are of course JSON specific. Then a couple of weeks ago, a requirement came in that an old desktop application needs to also consume this API and it has to use XML to do it because there’s no JSON parser available for it. Ooops – stuck with JSON in this case. While it would have been easy to add XML specific methods I figured it’s easier to add basic content negotiation. And that’s what I show in this post. Missteps – IResultFilter, IActionFilter My first attempt at this was to use IResultFilter or IActionFilter which look like they would be ideal to modify result content after it’s been generated using OnResultExecuted() or OnActionExecuted(). Filters are great because they can look globally at all controller methods or individual methods that are marked up with the Filter’s attribute. But it turns out these filters don’t work for raw POCO result values from Action methods. What we wanted to do for API calls is get back to using plain .NET types as results rather than result actions. That is you write a method that doesn’t return an ActionResult, but a standard .NET type like this:public Customer UpdateCustomer(Customer cust) { … do stuff to customer :-) return cust; } Unfortunately both OnResultExecuted and OnActionExecuted receive an MVC ContentResult instance from the POCO object. MVC basically takes any non-ActionResult return value and turns it into a ContentResult by converting the value using .ToString(). Ugh. The ContentResult itself doesn’t contain the original value, which is lost AFAIK with no way to retrieve it. So there’s no way to access the raw customer object in the example above. Bummer. Creating a NegotiatedResult This leaves mucking around with custom ActionResults. ActionResults are MVC’s standard way to return action method results – you basically specify that you would like to render your result in a specific format. Common ActionResults are ViewResults (ie. View(vn,model)), JsonResult, RedirectResult etc. They work and are fairly effective and work fairly well for testing as well as it’s the ‘standard’ interface to return results from actions. The problem with the this is mainly that you’re explicitly saying that you want a specific result output type. This works well for many things, but sometimes you do want your result to be negotiated. My first crack at this solution here is to create a simple ActionResult subclass that looks at the Accept header and based on that writes the output. I need to support JSON and XML content and HTML as well as text – so effectively 4 media types: application/json, text/xml, text/html and text/plain. Everything else is passed through as ContentResult – which effecively returns whatever .ToString() returns. Here’s what the NegotiatedResult usage looks like:public ActionResult GetCustomers() { return new NegotiatedResult(repo.GetCustomers()); } public ActionResult GetCustomer(int id) { return new NegotiatedResult("Show", repo.GetCustomer(id)); } There are two overloads of this method – one that returns just the raw result value and a second version that accepts an optional view name. The second version returns the Razor view specified only if text/html is requested – otherwise the raw data is returned. This is useful in applications where you have an HTML front end that can also double as an API interface endpoint that’s using the same model data you send to the View. For the application I mentioned above this was another actual use-case we needed to address so this was a welcome side effect of creating a custom ActionResult. There’s also an extension method that directly attaches a Negotiated() method to the controller using the same syntax:public ActionResult GetCustomers() { return this.Negotiated(repo.GetCustomers()); } public ActionResult GetCustomer(int id) { return this.Negotiated("Show",repo.GetCustomer(id)); } Using either of these mechanisms now allows you to return JSON, XML, HTML or plain text results depending on the Accept header sent. Send application/json you get just the Customer JSON data. Ditto for text/xml and XML data. Pass text/html for the Accept header and the "Show.cshtml" Razor view is rendered passing the result model data producing final HTML output. While this isn’t as clean as passing just POCO objects back as I had intended originally, this approach fits better with how MVC action methods are intended to be used and we get the bonus of being able to specify a View to render (optionally) for HTML. How does it work An ActionResult implementation is pretty straightforward. You inherit from ActionResult and implement the ExecuteResult method to send your output to the ASP.NET output stream. ActionFilters are an easy way to effectively do post processing on ASP.NET MVC controller actions just before the content is sent to the output stream, assuming your specific action result was used. Here’s the full code to the NegotiatedResult class (you can also check it out on GitHub):/// <summary> /// Returns a content negotiated result based on the Accept header. /// Minimal implementation that works with JSON and XML content, /// can also optionally return a view with HTML. /// </summary> /// <example> /// // model data only /// public ActionResult GetCustomers() /// { /// return new NegotiatedResult(repo.Customers.OrderBy( c=> c.Company) ) /// } /// // optional view for HTML /// public ActionResult GetCustomers() /// { /// return new NegotiatedResult("List", repo.Customers.OrderBy( c=> c.Company) ) /// } /// </example> public class NegotiatedResult : ActionResult { /// <summary> /// Data stored to be 'serialized'. Public /// so it's potentially accessible in filters. /// </summary> public object Data { get; set; } /// <summary> /// Optional name of the HTML view to be rendered /// for HTML responses /// </summary> public string ViewName { get; set; } public static bool FormatOutput { get; set; } static NegotiatedResult() { FormatOutput = HttpContext.Current.IsDebuggingEnabled; } /// <summary> /// Pass in data to serialize /// </summary> /// <param name="data">Data to serialize</param> public NegotiatedResult(object data) { Data = data; } /// <summary> /// Pass in data and an optional view for HTML views /// </summary> /// <param name="data"></param> /// <param name="viewName"></param> public NegotiatedResult(string viewName, object data) { Data = data; ViewName = viewName; } public override void ExecuteResult(ControllerContext context) { if (context == null) throw new ArgumentNullException("context"); HttpResponseBase response = context.HttpContext.Response; HttpRequestBase request = context.HttpContext.Request; // Look for specific content types if (request.AcceptTypes.Contains("text/html")) { response.ContentType = "text/html"; if (!string.IsNullOrEmpty(ViewName)) { var viewData = context.Controller.ViewData; viewData.Model = Data; var viewResult = new ViewResult { ViewName = ViewName, MasterName = null, ViewData = viewData, TempData = context.Controller.TempData, ViewEngineCollection = ((Controller)context.Controller).ViewEngineCollection }; viewResult.ExecuteResult(context.Controller.ControllerContext); } else response.Write(Data); } else if (request.AcceptTypes.Contains("text/plain")) { response.ContentType = "text/plain"; response.Write(Data); } else if (request.AcceptTypes.Contains("application/json")) { using (JsonTextWriter writer = new JsonTextWriter(response.Output)) { var settings = new JsonSerializerSettings(); if (FormatOutput) settings.Formatting = Newtonsoft.Json.Formatting.Indented; JsonSerializer serializer = JsonSerializer.Create(settings); serializer.Serialize(writer, Data); writer.Flush(); } } else if (request.AcceptTypes.Contains("text/xml")) { response.ContentType = "text/xml"; if (Data != null) { using (var writer = new XmlTextWriter(response.OutputStream, new UTF8Encoding())) { if (FormatOutput) writer.Formatting = System.Xml.Formatting.Indented; XmlSerializer serializer = new XmlSerializer(Data.GetType()); serializer.Serialize(writer, Data); writer.Flush(); } } } else { // just write data as a plain string response.Write(Data); } } } /// <summary> /// Extends Controller with Negotiated() ActionResult that does /// basic content negotiation based on the Accept header. /// </summary> public static class NegotiatedResultExtensions { /// <summary> /// Return content-negotiated content of the data based on Accept header. /// Supports: /// application/json - using JSON.NET /// text/xml - Xml as XmlSerializer XML /// text/html - as text, or an optional View /// text/plain - as text /// </summary> /// <param name="controller"></param> /// <param name="data">Data to return</param> /// <returns>serialized data</returns> /// <example> /// public ActionResult GetCustomers() /// { /// return this.Negotiated( repo.Customers.OrderBy( c=> c.Company) ) /// } /// </example> public static NegotiatedResult Negotiated(this Controller controller, object data) { return new NegotiatedResult(data); } /// <summary> /// Return content-negotiated content of the data based on Accept header. /// Supports: /// application/json - using JSON.NET /// text/xml - Xml as XmlSerializer XML /// text/html - as text, or an optional View /// text/plain - as text /// </summary> /// <param name="controller"></param> /// <param name="viewName">Name of the View to when Accept is text/html</param> /// /// <param name="data">Data to return</param> /// <returns>serialized data</returns> /// <example> /// public ActionResult GetCustomers() /// { /// return this.Negotiated("List", repo.Customers.OrderBy( c=> c.Company) ) /// } /// </example> public static NegotiatedResult Negotiated(this Controller controller, string viewName, object data) { return new NegotiatedResult(viewName, data); } } Output Generation – JSON and XML Generating output for XML and JSON is simple – you use the desired serializer and off you go. Using XmlSerializer and JSON.NET it’s just a handful of lines each to generate serialized output directly into the HTTP output stream. Please note this implementation uses JSON.NET for its JSON generation rather than the default JavaScriptSerializer that MVC uses which I feel is an additional bonus to implementing this custom action. I’d already been using a custom JsonNetResult class previously, but now this is just rolled into this custom ActionResult. Just keep in mind that JSON.NET outputs slightly different JSON for certain things like collections for example, so behavior may change. One addition to this implementation might be a flag to allow switching the JSON serializer. Html View Generation Html View generation actually turned out to be easier than anticipated. Initially I used my generic ASP.NET ViewRenderer Class that can render MVC views from any ASP.NET application. However it turns out since we are executing inside of an active MVC request there’s an easier way: We can simply create a custom ViewResult and populate its members and then execute it. The code in text/html handling code that renders the view is simply this:response.ContentType = "text/html"; if (!string.IsNullOrEmpty(ViewName)) { var viewData = context.Controller.ViewData; viewData.Model = Data; var viewResult = new ViewResult { ViewName = ViewName, MasterName = null, ViewData = viewData, TempData = context.Controller.TempData, ViewEngineCollection = ((Controller)context.Controller).ViewEngineCollection }; viewResult.ExecuteResult(context.Controller.ControllerContext); } else response.Write(Data); which is a neat and easy way to render a Razor view assuming you have an active controller that’s ready for rendering. Sweet – dependency removed which makes this class self-contained without any external dependencies other than JSON.NET. Summary While this isn’t exactly a new topic, it’s the first time I’ve actually delved into this with MVC. I’ve been doing content negotiation with Web API and prior to that with my REST library. This is the first time it’s come up as an issue in MVC. But as I have worked through this I find that having a way to specify both HTML Views *and* JSON and XML results from a single controller certainly is appealing to me in many situations as we are in this particular application returning identical data models for each of these operations. Rendering content negotiated views is something that I hope ASP.NET vNext will provide natively in the combined MVC and WebAPI model, but we’ll see how this actually will be implemented. In the meantime having a custom ActionResult that provides this functionality is a workable and easily adaptable way of handling this going forward. Whatever ends up happening in ASP.NET vNext the abstraction can probably be changed to support the native features of the future. Anyway I hope some of you found this useful if not for direct integration then as insight into some of the rendering logic that MVC uses to get output into the HTTP stream… Related Resources Latest Version of NegotiatedResult.cs on GitHub Understanding Action Controllers Rendering ASP.NET Views To String© Rick Strahl, West Wind Technologies, 2005-2014Posted in MVC ASP.NET HTTP Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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I finished coding my program. What's next? what are the steps I should take that would enable me to

- by Luay

Hi, I finished developing a program and would like to sell it online. However, I am not really sure of what to do next. Here is my current plan (in-order): 1- Add a 'deployment' project (i'm using visual studio) to my project so I can create a setup file for my program. 2- Use visual studio 'testing' add ons to test the program. I have no idea how to do it, but will teach myself. 3- When all is done, install the program on my wife's, parents and in-laws computer to further test it under different environments. 3- Setup a small Ltd. company. ( I might start this earlier as it might take a few weeks to complete). 4- Build / finish building a website (actually I started on this step a few weeks ago but haven't devoted enough time for it to complete yet). 5- Find a software / service to protect my program from piracy. I know it is impossible to protect the program from piracy. I understand that fully. But I still want to implement some sort of solution that wouldn't harm or deter honest customers. 6- Set up a business paypal account. 7- Find a software / service to handle payments on my website 8- Find a software / service to handle issuing license codes 9- Set up all of the above and go 'live'. However, I have zero experience in this sort of thing and would like your guidance on some points. 1- Is it necessary to setup a company? Can I sell as an individual? Will selling as an individual deter persons or companies from buying my software? 2- What is a decent choice for as a software / service to protect my program from my piracy. I have done a quick search and found something called Quick License Manager by Interactive Studios. Is this the sort of thing I am looking for? Is it any good? At which stage do I use or implement their service (or any similar service you might point me too? I guess I am really asking: how does this work? Would they give me a file I just add to my project, rebuild it and that's it? 3- What should I implement to handle payments online and how complicated is it? could you point me to any such services, please? 4- What should I implement to handle issuing license codes and how will that software / service coordinate with the software / service that handles the anti-piracy stuff? could you point me to such services, please? 5- In a different Stack Overflow question (by another user) someone suggested a cms system called Software Droid (http://www.softwaredroid.com). Is this what I am after. Will it help? 6- If the steps i'm following are incorrect in order or logic could you please advise me on what I should actually do? I guess these are question for those of you who have 'been there and done that'. So any guidance will be vary much appreciated. Many thanks in advance for your help.

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apache mod_jk loadbalancing issue for glassfish cluster instances

- by SibzTer

I have a JEE ear application deployed on 2 clusters with 2 instances each on Glassfish v3.1. These are load balanced by an Apache server running on the same machine. My problem is that I am frequently seeing the following error messages frequently in the mod_jk.log file. Can you help me understand what the issue is? [Mon Jun 13 09:37:51 2011] [7116:7852] [info] ajp_process_callback::jk_ajp_common.c (1885): Writing to client aborted or client network problems [Mon Jun 13 09:37:51 2011] [7116:7852] [info] ajp_service::jk_ajp_common.c (2543): (viewerLocalInstance4) sending request to tomcat failed (unrecoverable), because of client write error (attempt=1) [Mon Jun 13 09:37:51 2011] loadbalancerLocal myServer 0.062500 [Mon Jun 13 09:37:51 2011] [7116:6512] [info] ajp_process_callback::jk_ajp_common.c (1885): Writing to client aborted or client network problems [Mon Jun 13 09:37:51 2011] [7116:6512] [info] ajp_service::jk_ajp_common.c (2543): (viewerLocalInstance4) sending request to tomcat failed (unrecoverable), because of client write error (attempt=1) [Mon Jun 13 09:37:52 2011] [7116:3080] [info] ajp_process_callback::jk_ajp_common.c (1885): Writing to client aborted or client network problems [Mon Jun 13 09:37:52 2011] [7116:3080] [info] ajp_service::jk_ajp_common.c (2543): (viewerLocalInstance4) sending request to tomcat failed (unrecoverable), because of client write error (attempt=1) [Mon Jun 13 09:38:21 2011] [7116:6512] [info] service::jk_lb_worker.c (1388): service failed, worker viewerLocalInstance4 is in local error state [Mon Jun 13 09:38:21 2011] [7116:7852] [info] service::jk_lb_worker.c (1388): service failed, worker viewerLocalInstance4 is in local error state [Mon Jun 13 09:38:21 2011] [7116:6512] [info] service::jk_lb_worker.c (1407): unrecoverable error 200, request failed. Client failed in the middle of request, we can't recover to another instance. [Mon Jun 13 09:38:21 2011] [7116:7852] [info] service::jk_lb_worker.c (1407): unrecoverable error 200, request failed. Client failed in the middle of request, we can't recover to another instance. [Mon Jun 13 09:38:21 2011] loadbalancerLocal myServer 29.046875 [Mon Jun 13 09:38:21 2011] loadbalancerLocal myServer 29.171875 [Mon Jun 13 09:38:21 2011] [7116:6512] [info] jk_handler::mod_jk.c (2620): Aborting connection for worker=loadbalancerLocal [Mon Jun 13 09:38:21 2011] [7116:7852] [info] jk_handler::mod_jk.c (2620): Aborting connection for worker=loadbalancerLocal [Mon Jun 13 09:38:21 2011] [7116:7852] [info] ajp_process_callback::jk_ajp_common.c (1885): Writing to client aborted or client network problems [Mon Jun 13 09:38:21 2011] [7116:7852] [info] ajp_service::jk_ajp_common.c (2543): (viewerLocalInstance4) sending request to tomcat failed (unrecoverable), because of client write error (attempt=1) [Mon Jun 13 09:38:21 2011] loadbalancerLocal myServer 0.156250 [Mon Jun 13 09:38:21 2011] loadbalancerLocal myServer 0.062500 [Mon Jun 13 09:38:22 2011] [7116:3080] [info] service::jk_lb_worker.c (1388): service failed, worker viewerLocalInstance4 is in local error state [Mon Jun 13 09:38:22 2011] [7116:3080] [info] service::jk_lb_worker.c (1407): unrecoverable error 200, request failed. Client failed in the middle of request, we can't recover to another instance.

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Escaping Variable in Cat

- by Peter

I'm trying to write a shell script over ssh via a bash prompt. The shell, however, insists on interpreting any variable I want to write instead of writing it directly to file. For example, cat <<EOF >checkup.sh\n'$command'EOF is simply written as '' to file. How do I get $command written instead? I've tried every practical method of escaping I can think of. If it changes anything, I'm doing it over PHP using phpseclib.

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external hard drive is no longer recognized, gives buffer I/O errors

- by BioGeek

Hi all, The external hard drive which contains all my photos and where I backed-up all my important documents is no longer recognized. It is a three month old 500GB Iomage Prestige Desktop Hard Drive. When I plug it in, it is recognised as a USB device, because it shows up when I type lsusb, but dmesg gives this error message. [19712.013250] usb 2-2: new high speed USB device using ehci_hcd and address 21 [19712.145347] usb 2-2: configuration #1 chosen from 1 choice [19712.147214] scsi25 : SCSI emulation for USB Mass Storage devices [19712.147514] usb-storage: device found at 21 [19712.147519] usb-storage: waiting for device to settle before scanning [19717.148978] usb-storage: device scan complete [19717.149527] scsi 25:0:0:0: Direct-Access ST350082 0AS PQ: 0 ANSI: 2 CCS [19717.151020] sd 25:0:0:0: Attached scsi generic sg2 type 0 [19717.151685] sd 25:0:0:0: [sdb] 976773168 512-byte logical blocks: (500 GB/465 GiB) [19717.160402] sd 25:0:0:0: [sdb] Write Protect is off [19717.160412] sd 25:0:0:0: [sdb] Mode Sense: 34 00 00 00 [19717.160418] sd 25:0:0:0: [sdb] Assuming drive cache: write through [19717.165685] sd 25:0:0:0: [sdb] Assuming drive cache: write through [19717.165691] sdb: sdb1 [19719.171808] sd 25:0:0:0: [sdb] Assuming drive cache: write through [19719.171818] sd 25:0:0:0: [sdb] Attached SCSI disk [19737.430998] sd 25:0:0:0: [sdb] Unhandled sense code [19737.431007] sd 25:0:0:0: [sdb] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [19737.431016] sd 25:0:0:0: [sdb] Sense Key : Medium Error [current] [19737.431027] sd 25:0:0:0: [sdb] Add. Sense: Unrecovered read error [19737.431038] end_request: I/O error, dev sdb, sector 6160463 [19737.431050] Buffer I/O error on device sdb1, logical block 6160400 [19737.431060] Buffer I/O error on device sdb1, logical block 6160401 [19737.431067] Buffer I/O error on device sdb1, logical block 6160402 [19737.431075] Buffer I/O error on device sdb1, logical block 6160403 [19737.431082] Buffer I/O error on device sdb1, logical block 6160404 [19737.431088] Buffer I/O error on device sdb1, logical block 6160405 [19737.431096] Buffer I/O error on device sdb1, logical block 6160406 [19737.431102] Buffer I/O error on device sdb1, logical block 6160407 [19737.431114] Buffer I/O error on device sdb1, logical block 6160408 [19737.431121] Buffer I/O error on device sdb1, logical block 6160409 [19737.712183] sd 6:0:0:0: [sdb] Unhandled sense code [19737.712191] sd 6:0:0:0: [sdb] Result: hostbyte=DID_ERROR driverbyte=DRIVER_SENSE [19737.712200] sd 6:0:0:0: [sdb] Sense Key : Hardware Error [current] [19737.712210] sd 6:0:0:0: [sdb] Add. Sense: No additional sense information [19737.712222] end_request: I/O error, dev sdb, sector 0 [19737.712232] Buffer I/O error on device sdb, logical block 0 Neither does the external drive show when I use fdisk: jeroen@phalacrocorax:~$ sudo fdisk -l [sudo] password for jeroen: Disk /dev/sda: 160.0 GB, 160041885696 bytes 255 heads, 63 sectors/track, 19457 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x000341ad Device Boot Start End Blocks Id System /dev/sda1 * 1 18714 150320173+ 83 Linux /dev/sda2 18715 19457 5968147+ 5 Extended /dev/sda5 18715 19457 5968116 82 Linux swap / Solaris` I popped the disk out of the casing put it on a SATA connect internally and then tried the file recovery programs testdisk/photorec and SpinRite, but both failed because they couldn't recognize the external harddisk. Do I have any other options?

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Slow Windows Explorer on Windows 7

- by MadBoy

I have Laptop with i7 (4 cores), 8GB ram and SSD OCZ Vertex 3 MaxIOPS which in testing that I did just now does 400mb/s+ read/write. However the responsiveness of Windows Explorer is far from being perfect. Opening up Computer, Documents, going into folders is very slow (1-5seconds). I don't have any viruses or spyware and I have tried changing properties to optimize view for General Items. I tried disabling Search Indexer but it made search in Outlook 2010 crawl and didn't bring any other effect. Even double clicking on file takes some time to open things up (like clicking a Word document). I don't have any drives mapped, my computer is not joined to domain. I have multiple VPN connections that I connect to but they all have disabled default gateways. I tried using CC Cleaner or some Windows 7 Tweaks app to disable some things. I am power user using Visual Studio, Tortoise SVN and other developer/administration apps. Any non obvious ideas? Edit: So I've been trying to pinpoint where the issue comes from and it seems that straight after reboot Windows Explorer opens very fast, when I load 3-4 programs (Royal TS, Visual Studio, Outlook) it's noticeably slower and the more programs I have it gets worse. After I start closing programs it starts working better and if I leave 2 open it's fast again. I tried doing some research with DiskMon and other programs from sysinternals but couldn't find anything suspicious. Below are stats during normal usage with a lots of programs open: - Ram usage with a lot of programs open and no swap file (i disabled it for testing): 6.95GB - CPU usage: 15%, none of the cores takes more then 50% (I have VS 2010 open x 4) HD Tune Pro: OCZ-VERTEX3 MI Benchmark Test capacity: full Read transfer rate Transfer Rate Minimum : 363.9 MB/s Transfer Rate Maximum : 505.5 MB/s Transfer Rate Average : Access Time : Burst Rate : CPU Usage : HD Tune Pro: OCZ-VERTEX3 MI File Benchmark Drive C: Transfer rate test File Size: 500 MB Sequential read 484102 KB/s Sequential write 444714 KB/s Random read 7779 IOPS Random write 16888 IOPS Random read (queue depth = 32) 73007 IOPS Random write (queue depth = 32) 69790 IOPS HD Tune Pro: OCZ-VERTEX3 MI Random Access Test capacity: full Read test Transfer size operations / sec avg. access time max. access time avg. speed 512 bytes 3260 IOPS 0.306 ms 2.106 ms 1.592 MB/s 4 KB 4161 IOPS 0.240 ms 2.006 ms 16.256 MB/s 64 KB 2382 IOPS 0.419 ms 2.367 ms 148.934 MB/s 1 MB 449 IOPS 2.225 ms 4.197 ms 449.407 MB/s Random 809 IOPS 1.235 ms 6.551 ms 410.527 MB/s HD Tune Pro: OCZ-VERTEX3 MI Extra Tests Test capacity: full Random seek 3975 IOPS 0.252 ms 1.941 MB/s Random seek 4 KB 4245 IOPS 0.236 ms 16.583 MB/s Butterfly seek 4086 IOPS 0.245 ms 1.995 MB/s Random seek / size 64 KB 3812 IOPS 0.262 ms 58.606 MB/s Random seek / size 8 MB 120 IOPS 8.348 ms 485.737 MB/s Sequential outer 4524 IOPS 0.221 ms 282.721 MB/s Sequential middle 4429 IOPS 0.226 ms 276.818 MB/s Sequential inner 5504 IOPS 0.182 ms 344.000 MB/s Burst rate 4472 IOPS 0.224 ms 279.475 MB/s

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Cannot SVN checkout when anon-access = none

- by sKIPper76

When I have anon-access = write Everything works fine. When I change svnserve.conf to: anon-access = none auth-access = write And uncomment password-db and authz-db AND add user in authz with rw AND put username/password in passwd, nothing works. Eclipse keeps giving me a "Cannot map the project with svn provider" error. I have given all the files under conf 777. Any ideas what's wrong?

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Auto populate Outlook with other users' calendars

- by bduncanj

In Outlook 2007, when in Calendar view, there's a category (group) of calendars on the left hand bar titled "People's Calendars". We're migrating from a system where all employees have access to read and write to all other employees' calendars (via a 3rd party Web Calendar). Is it possible, from an admin level, to auto-populate this People's Calendars category in everyone's Outlook with all the employees in the company, and grant everyone read / write access to everyone else's calendars? (Running Exchange 2010) Thanks, Duncan

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Help Selecting The Best WebHost

- by Joshua

Can anyone recommend a user-friendly (I'm new to website development) and inexpensive web host (my websites are simple and small, so no need for a beef-eating server) that will allow me write access to the file system from PHP? My current web host won't allow me to write to the file system, and keeping everything in the database is slow, and a pain.

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Is there any USB2.0 data transfer chunk size limit?

- by goldenmean

With one read() or write() at a time, can we increase the bulk data size over USB interface? For example, I want to transfer chunk of 1024 (1K) bytes data and if the device has limitations of only 64bytes, is there any way I can increase the packet size for read() and write() system call over USB? Is there any limitation on size of data transfer over USB in a host-device environment?

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How can I repair my USB drive?

- by yurko

USB drive is in read only state and I can't repair it. First of all I tried erase it using dd: root@yurko-laptop:/home/yurko-laptop# ls -l /dev/disk/by-id | grep usb lrwxrwxrwx 1 root root 9 ??? 18 23:45 usb-Generic_Flash_Disk_C173828A-0:0 -> ../../sdb lrwxrwxrwx 1 root root 10 ??? 18 23:45 usb-Generic_Flash_Disk_C173828A-0:0-part1 -> ../../sdb1 root@yurko-laptop:/home/yurko-laptop# dd if=/dev/zero of=/dev/sdb dd: ?????? ? «/dev/sdb»: ?? ?????????? ????????? ????? 8257537+0 ??????? ??????? 8257536+0 ??????? ???????? ??????????? 4227858432 ????? (4,2 GB), 942,633 c, 4,5 MB/c After that I wanted to create new filesystem using fdisk: root@yurko-laptop:/home/yurko-laptop# fdisk /dev/sdb You will not be able to write the partition table. WARNING: DOS-compatible mode is deprecated. It's strongly recommended to switch off the mode (command 'c') and change display units to sectors (command 'u'). Command (m for help): p Disk /dev/sdb: 4227 MB, 4227858432 bytes 4 heads, 63 sectors/track, 32768 cylinders Units = cylinders of 252 * 512 = 129024 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sdb1 18 32768 4126596 b W95 FAT32 Command (m for help): fdisk showed that the partition still exists and I can't write the partition table. I tried to delete the existing partition: Command (m for help): d Selected partition 1 Command (m for help): w Unable to write /dev/sdb root@yurko-laptop:/home/yurko-laptop# Why am I not be able to write the partition table? Does it mean that some hardware failure occurred? And is it possible to repair the current USB drive? I've tried to use hdparm and it showed that the readonly flag is on: root@yurko-laptop:/home/yurko-laptop# hdparm /dev/sdb /dev/sdb: SG_IO: bad/missing sense data, sb[]: f0 00 05 00 00 00 00 0a 00 00 00 00 26 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 multcount = 0 (off) readonly = 1 (on) readahead = 256 (on) geometry = 1016/131/62, sectors = 8257536, start = 0

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Apache Directive for Allow From

- by Dr. DOT

I want to button down write access on a particular file using the Allow form directive in my httpd.conf file. I have a PHP script that I want to be the only resource that can write to this file. Is there a variation of the Allow from that I can define to make this happen?

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