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  • Cannot use await in Portable Class Library for Win 8 and Win Phone 8

    - by Harry Len
    I'm attempting to create a Portable Class Library in Visual Studio 2012 to be used for a Windows 8 Store app and a Windows Phone 8 app. I'm getting the following error: 'await' requires that the type 'Windows.Foundation.IAsyncOperation' have a suitable GetAwaiter method. Are you missing a using directive for 'System'? At this line of code: StorageFolder guidesInstallFolder = await Package.Current.InstalledLocation.GetFolderAsync(guidesFolder); My Portable Class Library is targeted at .NET Framework 4.5, Windows Phone 8 and .NET for Windows Store apps. I don't get this error for this line of code in a pure Windows Phone 8 project, and I don't get it in a Windows Store app either so I don't understand why it won't work in my PCL. The GetAwaiter is an extension method in the class WindowsRuntimeSystemExtensions which is in System.Runtime.WindowsRuntime.dll. Using the Object Browser I can see this dll is available in the .NET for Windows Store apps component set and in the Windows Phone 8 component set but not in the .NET Portable Subset. I just don't understand why it wouldn't be in the Portable Subset if it's available in both my targeted platforms.

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  • Error when calling SQL SP via LINQ

    - by PaulC
    Newbie problem: I have a SQL SP with ten parameters (eight input, two output) but when I attempt to call it via LINQ from code I get the following error message: "The best overloaded method match for 'DataClassesDataContext.ST_CR_CREATE_CASE_BASIS(string, string, string, string, System.DateTime?, string, string, string, ref int?, ref int?)' has some invalid arguments". The params with ? appear to be unrecognized, but I'm baffled: the data types match the SQL types, the number of parameters match, the other parmeters don't exhibit the same behaviour. Can anyone tell me what's going on? Thanks in advance. -- SQL SP: create procedure ST_CR_CREATE_CASE_BASIS @p_Pers_No nvarchar (50), @p_Subject nvarchar (255), @p_RQ_XML nvarchar(max), @p_RQ_XSL nvarchar(max), @p_Date_Submit smalldatetime, @p_User_ID_Submit nvarchar (255), @p_RQ_Status nvarchar (50), @p_User_ID_OnBehalf nvarchar (255), @p_Case_Number int output, @p_RQ_ID int output as begin -- ... etc.; the SP works fine when called from SSMS The code-behind proc from the aspx page looks like this: protected void cmdSubmit_Click(object sender, EventArgs e) { using (DataClassesDataContext vDataCont = new DataClassesDataContext()) { Int32 vNewCaseNr; Int32 vNewReqNr; DateTime vNow = System.DateTime.Now; vDataCont.ST_CR_CREATE_CASE_BASIS("101", "Test Subject Late Wed", null, null, vNow , "101", "1", "101", ref vNewCaseNr, vNewReqNr); } }

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  • Combining properties made available via webservices profile service aspnet

    - by Adam
    I really wasn't sure what the title for my question could be, so sorry if it's a bit vague. I'm working on an application that uses client application services for authentication/profile management etc. In web.config for my website, I have the following profile properties like this: <properties> <add name="FirstName" type="string" defaultValue="" customProviderData="FirstName;nvarchar"/> ... Basic things like first name, last name etc. I'm exposing properties for my client app like this: <system.web.extensions> <scripting> <webServices> <authenticationService enabled="true" requireSSL="false"/> <profileService enabled="true" readAccessProperties="UserProfile" writeAccessProperties="UserProfile"/> <roleService enabled="true"/> </webServices> </scripting> </system.web.extensions> What I'm wondering is whether it's possible to bundle all the individual profile properties into a single object for client apps to utilize? I originally had all my profile data stored as members of a single class (UserProfile) but I broke it all out so that I could use the SqlTableProfileProvider to store each field as individual columns in relevant tables. I know I can create an class with members for each type, I'm just not sure if there's an easy way to create an object with all my property values (other than assigning values to this object whenever I assign to the the standalone properties). I don't think I'm explaining this very well, so I'll try an example. Say in my website profile I have FirstName and LastName as properties. For my client application profileService I want to have one ReadAccessProperty FullName. Is there some way to automatically create FullName from the existing FirstName and LastName properties without having to also have a seperate FullName property (and manually assign data to it whenever I assign data to FirstName and LastName)?

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  • Inverted colours in tiff to PDF conversion

    - by spiderdijon
    I'm sure I'm making some kind of silly mistake here, but when converting a tiff file to PDF, the colours become reversed. I can't figure out why. Here's my code: PdfWriter writer = PdfWriter.GetInstance(document, new FileStream("Image.pdf", FileMode.Create)); System.Drawing.Bitmap bm = new System.Drawing.Bitmap(@"C:\Temp\338814-00.tif"); int total = bm.GetFrameCount(FrameDimension.Page); document.Open(); PdfContentByte cb = writer.DirectContent; for (int k = 0; k < total; ++k) { bm.SelectActiveFrame(FrameDimension.Page, k); MemoryStream ms = new MemoryStream(); bm.Save(ms, ImageFormat.Tiff); Image img = Image.GetInstance(ms.ToArray()); img.ScalePercent(72f / (float)img.DpiX * 100); img.SetAbsolutePosition(0, 0); cb.AddImage(img); document.NewPage(); } document.Close(); Thanks.

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  • Using authsmtp from a Grails server

    - by Simon
    This is quite a specific question, and I have had no luck on the grails nabble forum, so I thought I would post here. I am using the grails mail plug-in, but I think my question is a general one about using authsmtp as an email gateway from my server. I am having trouble sending mail from my app using authsmtp. I have installed and configured the mail plugin and was originally using my ISP's SMTP server to send mails. However when I deployed to AWS EC2 this failed because my elastic IP was blocked by the SMTP host. So I bought myself an authsmtp account and set up my server email address as an accepted one at authsmtp. I then changed my configuration in SecurityConfig.groovy to point to the authsmtp server that I had been designated... mailHost = "mail.authsmtp.com" mailUsername = "myusername" mailPassword = "mypassword" mailProtocol = "smtp" mailFrom = "[email protected]" mailPort = 2525 ...and I'm just trying to get this to work locally before I deploy back up to AWS. Sending mail fails and in my log I have this exception: 2010-02-13 10:59:44,218 [http-8080-1] ERROR service.EmailerService - Failed to send emails: Failed messages: com.sun.mail.smtp.SMTPSendFailedException: 513 5.0.0 Your email system must authenticate before sending mail. org.springframework.mail.MailSendException; nested exception details (1) are: Failed message 1: com.sun.mail.smtp.SMTPSendFailedException: 513 5.0.0 Your email system must authenticate before sending mail. at com.sun.mail.smtp.SMTPTransport.issueSendCommand(SMTPTransport.java:1388) at com.sun.mail.smtp.SMTPTransport.mailFrom(SMTPTransport.java:959) at com.sun.mail.smtp.SMTPTransport.sendMessage(SMTPTransport.java:583) I'm a bit lost since the username and password I provide in the configuration are definitely correct. A terse and not very helpful conversation with authsmtp support suggests that I need to MD5 and/or base64 encode my credentials before sending, so my question is in three parts... 1) any idea what's going on with the failure and why that message is appearing? 2) how would I encode the credentials to pass to authsmtp and how would I configure that for the mail plugin 3) has anyone successfully connected and sent mail through authsmtp from the mail plugin and specifically from AWS EC2?

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  • VS2010 express beta2 - no add reference dialog, no open file/project dialogs

    - by David
    Just installed VS2010 express for Windows Phone last night. Install went smoothly. It creates a project, compiles, and deploys the app to the emulator. Here's the problem: When I try to "Add Reference" through the Project menu, I do not get the Add Reference dialog box. Same thing if I right click References in the solution explorer and click Add Reference. That's not all. "File...Open" and "File...Open Project" also fail to throw up an open file dialog box. When attempting any of these actions, the IDE quickly loses and regains focus. Even pressing a keyboard shortcut (Ctrl+O) causes the IDE to quickly lose and regain focus, but no open file dialog box appears. This is what I have tried, not particularly in this order: 1. Turned off UAC 2. Monitored file and registry access using Process Monitor during a File...Open operation. File activity showed mostly "SUCCESS" with a few "FAST IO DISALLOWED" and a few "INVALID DEVICE REQUEST" results. Registry activity showed mostly "SUCCESS" with some "NAME NOT FOUND" and a few "BUFFER OVERFLOW" results. 3. Created a new, clean Windows account to run the IDE from 4. Forced a test project to add a reference to "System.Xml.Linq" by editing the ".csproj" project file. Project failed to load in the IDE. I don't have these problems at all on 2 other Windows 7 computers with VS2010 C# express beta 2 installed. One machine is 32bit and the other 64bit, both Home Premium edition. My system: Windows 7 Home Premium, 64bit Other Visual Studio products installed: VS2008 C# express, VS2008 C++ express One other thing to note: Several months ago I installed the non-phone distribution of VS2010 C# express beta 2, and I had the same exact problems. Back then I chalked it up to being beta and went back to VS2008 C# express, where I do not have these issues.

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  • Uninterruptible Windows Process

    - by Nullstr1ng
    Hi Guys, We're starting a new custom project right now from a client and one of the requirements is the process cannot be terminated unless the system is shutting down, restarting, or logging-off. This application monitors the USB interface. We will be using WMI to query the device periodically. The client want's to run the application on Windows XP Operating System and doesn't like installing .NET. So we targeted Visual Basic 6 as our language. My main concern is this application cannot be terminated. Our Project Adviser talks about Anti-virus and yes, some of the anti virus cannot be terminated. I was thinking how to do the same in Visual Basic 6. I know there will be API involved on the project but where should I go? so API is ok with me. I saw some articles that converts the EXE to a SERVICE, create Windows Service in Visual Basic 6, etc. So please .. share your thoughts.

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  • Splitting EJBs and interfaces into separate module -- deployment fails

    - by Hank
    I'm having trouble following this guide to "extract" my interfaces and entities from my EAR to use them from another Web Application: I use NetBeans 6.8 and Glassfish 3.0.1 "Java Class Library" project contains all the entities and interfaces "Java EE Application" project class library added to the project, is packaged into the EAR contains EJB implementations, MDBs, Test "Java Web Application" project class library added to the project, is packaged into the WAR contains REST interface When I build and deploy the Web Application, all goes well. When I build the JEE application, I can see the jar-file (interfaces, entities) being included. But when I try to deploy the EAR, Glassfish refuses it with a java.lang.NoClassDefFoundError error: [#|2010-03-28T18:25:59.875+0200|WARNING|glassfishv3.0|javax.enterprise.system.tools.deployment.org.glassfish.deployment.common|_ThreadID=28;_ThreadName=Thread-1;|Error in annotation processing: java.lang.NoClassDefFoundError: mvs/core/StoreServiceLocal|#] [#|2010-03-28T18:25:59.876+0200|SEVERE|glassfishv3.0|javax.enterprise.system.core.com.sun.enterprise.v3.server|_ThreadID=28;_ThreadName=Thread-1;|Exception while deploying the app java.lang.IllegalArgumentException: Invalid ejb jar [CoreServer]: it contains zero ejb. Note: 1. A valid ejb jar requires at least one session, entity (1.x/2.x style), or message-driven bean. 2. EJB3+ entity beans (@Entity) are POJOs and please package them as library jar. 3. If the jar file contains valid EJBs which are annotated with EJB component level annotations (@Stateless, @Stateful, @MessageDriven, @Singleton), please check server.log to see whether the annotations were processed properly. 'mvs/core/StoreServiceLocal' is an interface which is defined in the library jar file. What am I doing wrong?

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  • Examples of monoids/semigroups in programming

    - by jkff
    It is well-known that monoids are stunningly ubiquitous in programing. They are so ubiquitous and so useful that I, as a 'hobby project', am working on a system that is completely based on their properties (distributed data aggregation). To make the system useful I need useful monoids :) I already know of these: Numeric or matrix sum Numeric or matrix product Minimum or maximum under a total order with a top or bottom element (more generally, join or meet in a bounded lattice, or even more generally, product or coproduct in a category) Set union Map union where conflicting values are joined using a monoid Intersection of subsets of a finite set (or just set intersection if we speak about semigroups) Intersection of maps with a bounded key domain (same here) Merge of sorted sequences, perhaps with joining key-equal values in a different monoid/semigroup Bounded merge of sorted lists (same as above, but we take the top N of the result) Cartesian product of two monoids or semigroups List concatenation Endomorphism composition. Now, let us define a quasi-property of an operation as a property that holds up to an equivalence relation. For example, list concatenation is quasi-commutative if we consider lists of equal length or with identical contents up to permutation to be equivalent. Here are some quasi-monoids and quasi-commutative monoids and semigroups: Any (a+b = a or b, if we consider all elements of the carrier set to be equivalent) Any satisfying predicate (a+b = the one of a and b that is non-null and satisfies some predicate P, if none does then null; if we consider all elements satisfying P equivalent) Bounded mixture of random samples (xs+ys = a random sample of size N from the concatenation of xs and ys; if we consider any two samples with the same distribution as the whole dataset to be equivalent) Bounded mixture of weighted random samples Which others do exist?

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  • Error with Property Validation in Form Submission in ASP.NET MVC

    - by Maxim Z.
    I have a simple form on an ASP.NET MVC site that I'm building. This form is submitted, and then I validate that the form fields aren't null, empty, or improperly formatted. However, when I use ModelState.AddModelError() to indicate validation errors from my controller code, I get an error when my view is re-rendered. In Visual Studio, I get that the following line is highlighted as being the location of the error: <%=Html.TextBox("Email")%> The error is the following: NullReferenceException was unhandled by user code - object reference not set to an instance of an object. My complete code for that textbox is the following: <p> <label for="Email">Your Email:</label> <%=Html.TextBox("Email")%> <%=Html.ValidationMessage("Email", "*") %> </p> Here's how I'm doing that validation in my controller: try { System.Net.Mail.MailAddress address = new System.Net.Mail.MailAddress(email); } catch { ModelState.AddModelError("Email", "Should not be empty or invalid"); } return View(); Note: this applies to all of my fields, not just my Email field, as long as they are invalid.

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  • Help using RDA on a Desktop Applicaton?

    - by Joel
    I have a .NET 3.5 Compact Framework project that uses RDA for moving data between its mobile device's local SqlCe database and a remote MSSql-2008 server(it uses RDA Push and Pull). The server machine a virtual directory with sqlcesa35.dll (v3.5.5386.0) setup for RDA. We usually install these cabs on the mobile devices and the RDA process does not have any problems: sqlce.wce5.armv4i.cab sqlce.repl.wce5.armv4i.cab Now I am trying to run this application as a desktop application. RDA Pull (download) has been working well. But the RDA Push (upload) is giving me some problems. This is the exception that I get on the desktop application when I try to use RDA Push: System.Data.SqlServerCe.SqlCeException The Client Agent and Server Agent component versions are incompatible. The compatible versions are: Client Agent versions 3.0 and 3.5 with Server Agent versions 3.5 and Client Agent version 3.5 with Server Agent version 3.5. Re-install the replication components with the matching versions for client and server agents. [ 35,30,Client Agent version = ,Server Agent version = ] I have tried copying the file C:\Program Files\Microsoft SQL Server Compact Edition\v3.5\Desktop\SqlServerCe.dll (v3.5.5692.0) to bin\debug I have also tried copying another version of SqlServerCe.dll (v3.0.5206.0) to bin\debug. But this just gives me a slightly different exception: System.Data.SqlServerCe.SqlCeException [ 35,30 ] Is there a different setup or any different dlls that I need to use? Thanks, -Joel

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  • Invalid argument in sendfile() with two regular files

    - by Daniel Hershcovich
    I'm trying to test the sendfile() system call under Linux 2.6.32 to zero-copy data between two regular files. As far as I understand, it should work: ever since 2.6.22, sendfile() has been implemented using splice(), and both the input file and the output file can be either regular files or sockets. The following is the content of sendfile_test.c: #include <sys/sendfile.h> #include <fcntl.h> #include <stdio.h> int main(int argc, char **argv) { int result; int in_file; int out_file; in_file = open(argv[1], O_RDONLY); out_file = open(argv[2], O_WRONLY | O_CREAT | O_TRUNC, 0644); result = sendfile(out_file, in_file, NULL, 1); if (result == -1) perror("sendfile"); close(in_file); close(out_file); return 0; } And when I'm running the following commands: $ gcc sendfile_test.c $ ./a.out infile The output is sendfile: Bad file descriptor Which means that the system call resulted in errno = -EINVAL, I think. What am I doing wrong?

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  • Passing arguments to commandline with directories having spaces

    - by superstar
    Hi guys, I am making a system call from perl for ContentCheck.pl and passing parameters with directories (having spaces). So I pass them in quotes, but they are not being picked up in the ContentCheck.pl file Random.pm my $call = "$perlExe $contentcheck -t $target_path -b $base_path -o $output_path -s $size_threshold"; print "\ncall: ".$call."\n"; system($call); Contentcheck.pl use vars qw($opt_t $opt_b $opt_o $opt_n $opt_s $opt_h); # initialize getopts('t:b:o:n:s:h') or do{ print "*** Error: Invalid command line option. Use option -h for help.\a\n"; exit 1}; if ($opt_h) {print $UsagePage; exit; } my $tar; if ($opt_t) {$tar=$opt_t; print "\ntarget ".$tar."\n";} else { print " in target"; print "*** Error: Invalid command line option. Use option -h for help.\a\n"; exit 1;} my $base; if ($opt_b) {$base=$opt_b;} else { print "\nin base\n"; print "*** Error: Invalid command line option. Use option -h for help.\a\n"; exit 1;} This is the output in the commandline call: D:\tools\PacketCreationTool/bin/perl/winx64/bin/perl.exe D:/tools/PacketCr eationTool/scripts/ContentCheck.pl -t "C:/Documents and Settings/pkkonath/Deskto p/saved/myMockName.TGZ" -b "input file/myMockName.TGZ" -o myMockName.validate -s 10 target C:/Documents in base *** Error: Invalid command line option. Use option -h for help. Any suggestions are welcome! Thanks.

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  • php user authentication libraries / frameworks ... what are the options?

    - by es11
    I am using PHP and the codeigniter framework for a project I am working on, and require a user login/authentication system. For now I'd rather not use SSL (might be overkill and the fact that I am using shared hosting discourages this). I have considered using openID but decided that since my target audience is generally not technical, it might scare users away (not to mention that it requires mirroring of login information etc.). I know that I could write a hash based authentication (such as sha1) since there is no sensitive data being passed (I'd compare the level of sensitivity to that of stackoverflow). That being said, before making a custom solution, it would be nice to know if there are any good libraries or packages out there that you have used to provide semi-secure authentication? I am new to codeigniter, but something that integrates well with it would be preferable. Any ideas? (i'm open to criticism on my approach and open to suggestions as to why I might be crazy not to just use ssl). Thanks in advance. Update: I've looked into some of the suggestions. I am curious to try out zend-auth since it seems well supported and well built. Does anyone have experience with using zend-auth in codeigniter (is it too bulky?) and do you have a good reference on integrating it with CI? I do not need any complex authentication schemes..just a simple login/logout/password-management authorization system. Also, dx_auth seems interesting as well, however I am worried that it is too buggy. Has anybody else had success with this? I realized that I would also like to manage guest users (i.e. users that do not login/register) in a similar way to stackoverflow..so any suggestions that have this functionality would be great

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  • Ruby and duck typing: design by contract impossible?

    - by davetron5000
    Method signature in Java: public List<String> getFilesIn(List<File> directories) similar one in ruby def get_files_in(directories) In the case of Java, the type system gives me information about what the method expects and delivers. In Ruby's case, I have no clue what I'm supposed to pass in, or what I'll expect to receive. In Java, the object must formally implement the interface. In Ruby, the object being passed in must respond to whatever methods are called in the method defined here. This seems highly problematic: Even with 100% accurate, up-to-date documentation, the Ruby code has to essentially expose its implementation, breaking encapsulation. "OO purity" aside, this would seem to be a maintenance nightmare. The Ruby code gives me no clue what's being returned; I would have to essentially experiment, or read the code to find out what methods the returned object would respond to. Not looking to debate static typing vs duck typing, but looking to understand how you maintain a production system where you have almost no ability to design by contract. Update No one has really addressed the exposure of a method's internal implementation via documentation that this approach requires. Since there are no interfaces, if I'm not expecting a particular type, don't I have to itemize every method I might call so that the caller knows what can be passed in? Or is this just an edge case that doesn't really come up?

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  • ASP.NET MVC Creating a impersonated user.

    - by Malcolm
    Hi, I have a MVC app where I have a User class and the user can also impersonate another user(Admin users only). So I have this code below that authenticates the request and instantiates my version of a User class. It then tries to get the impersonated user from the Session object but Session is not available in this method in the global.asax. Hope this makes sense. How else could I do this? protected void Application_OnAuthenticateRequest(object sender, EventArgs e) { IMylesterService service = ObjectFactory.GetInstance(); if (Context.User != null) { if (Context.User.Identity.IsAuthenticated) { User user = service.GetUser(Context.User.Identity.Name); if (user == null) throw new ApplicationException("Context.user.Identity.name is not a recognized user"); User impersonatedUser = (User)this.Session["ImpersonatedUser"]; if (impersonatedUser == null) user.ImpersonatedUser = user; else user.ImpersonatedUser = impersonatedUser; System.Threading.Thread.CurrentPrincipal = Context.User = user; return; } } User guest = service.GetGuestUser(); guest.ImpersonatedUser = guest; System.Threading.Thread.CurrentPrincipal = Context.User = guest; }

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  • Whats the wrong with this code?

    - by girinie
    Hi in this code first I am downloading a web-page source code then I am storing the code in text file. Again I am reading that file and matching with the regex to search a specific string. There is no compiler error. Exception in thread "main" java.lang.NoClassDefFoundError: java/lang/CharSequence Can anybody tell me Where I am wrong. import java.io.*; import java.net.*; import java.lang.*; import java.util.regex.Matcher; import java.util.regex.Pattern; public class WebDownload { public void getWebsite() { try{ URL url=new URL("www.gmail.com");// any URL can be given URLConnection urlc=url.openConnection(); BufferedInputStream buffer=new BufferedInputStream(urlc.getInputStream()); StringBuffer builder=new StringBuffer(); int byteRead; FileOutputStream fout; StringBuffer contentBuf = new StringBuffer(); while((byteRead=buffer.read()) !=-1) { builder.append((char)byteRead); fout = new FileOutputStream ("myfile3.txt"); new PrintStream(fout).println (builder.toString()); fout.close(); } BufferedReader in = new BufferedReader(new FileReader("myfile3.txt")); String buf = null; while ((buf = in.readLine()) != null) { contentBuf.append(buf);contentBuf.append("\n"); } in.close(); Pattern p = Pattern.compile("<div class=\"summarycount\">([^<]*)</div>"); Matcher matcher = p.matcher(contentBuf); if(matcher.find()) { System.out.println(matcher.group(1)); } else System.out.println("could not find"); } catch(MalformedURLException ex) { ex.printStackTrace(); } catch(IOException ex){ ex.printStackTrace(); } } public static void main(String [] args) { WebDownload web=new WebDownload(); web.getWebsite(); } }

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  • How can I validate/secure/authenticate a JavaScript-based POST request?

    - by Bungle
    A product I'm helping to develop will basically work like this: A Web publisher creates a new page on their site that includes a <script> from our server. When a visitor reaches that new page, that <script> gathers the text content of the page and sends it to our server via a POST request (cross-domain, using a <form> inside of an <iframe>). Our server processes the text content and returns a response (via JSONP) that includes an HTML fragment listing links to related content around the Web. This response is cached and served to subsequent visitors until we receive another POST request with text content from the same URL, at which point we regenerate a "fresh" response. These POSTs only happen when our cached TTL expires, at which point the server signifies that and prompts the <script> on the page to gather and POST the text content again. The problem is that this system seems inherently insecure. In theory, anyone could spoof the HTTP POST request (including the referer header, so we couldn't just check for that) that sends a page's content to our server. This could include any text content, which we would then use to generate the related content links for that page. The primary difficulty in making this secure is that our JavaScript is publicly visible. We can't use any kind of private key or other cryptic identifier or pattern because that won't be secret. Ideally, we need a method that somehow verifies that a POST request corresponding to a particular Web page is authentic. We can't just scrape the Web page and compare the content with what's been POSTed, since the purpose of having JavaScript submit the content is that it may be behind a login system. Any ideas? I hope I've explained the problem well enough. Thanks in advance for any suggestions.

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  • Total Order between !different! volatile variables?

    - by andreas
    Hi all, Consider the following Java code: volatile boolean v1 = false; volatile boolean v2 = false; //Thread A v1 = true; if (v2) System.out.println("v2 was true"); //Thread B v2 = true; if (v1) System.out.println("v1 was true"); If there was a globally visible total order for volatile accesses then at least one println would always be reached. Is that actually guaranteed by the Java Standard? Or is an execution like this possible: A: v1 = true; B: v2 = true; A: read v2 = false; B: read v1 = false; A: v2 = true becomes visible (after the if) B: v1 = true becomes visible (after the if) I could only find statements about accesses to the same volatile variable in the Standard (but I might be missing something). "A write to a volatile variable (§8.3.1.4) v synchronizes-with all subsequent reads of v by any thread (where subsequent is defined according to the synchronization order)." http://java.sun.com/docs/books/jls/third_edition/html/memory.html#17.4.4 Thanks!

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  • NullPointerException with static variables

    - by tomekK
    I just hit very strange (to me) behaviour of java. I have following classes: public abstract class Unit { public static final Unit KM = KMUnit.INSTANCE; public static final Unit METERS = MeterUnit.INSTANCE; protected Unit() { } public abstract double getValueInUnit(double value, Unit unit); protected abstract double getValueInMeters(double value); } And: public class KMUnit extends Unit { public static final Unit INSTANCE = new KMUnit(); private KMUnit() { } //here are abstract methods overriden } public class MeterUnit extends Unit { public static final Unit INSTANCE = new MeterUnit(); private MeterUnit() { } ///abstract methods overriden } And my test case: public class TestMetricUnits extends TestCase { @Test public void testConversion() { System.out.println("Unit.METERS: " + Unit.METERS); System.out.println("Unit.KM: " + Unit.KM); double meters = Unit.KM.getValueInUnit(102.11, Unit.METERS); assertEquals(0.10211, meters, 0.00001); } } 1) MKUnit and MeterUnit are both singletons initialized statically, so during class loading. Constructors are private, so they can't be initialized anywhere else. 2) Unit class contains static final references to MKUnit.INSTANCE and MeterUnit.INSTANCE I would expect that: KMUnit class is loaded and instance is created. MeterUnit class is loaded and instance is created. Unit class is loaded and both KM and METERS variable are initialized, they are final so they cant be changed. But when I run my test case in console with maven my result is: T E S T S Running de.audi.echargingstations.tests.TestMetricUnits Unit.METERS: m Unit.KM: null Tests run: 3, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.089 sec <<< FAILURE! - in de.audi.echargingstations.tests.TestMetricUnits testConversion(de.audi.echargingstations.tests.TestMetricUnits) Time elapsed: 0.011 sec <<< ERROR! java.lang.NullPointerException: null at de.audi.echargingstations.tests.TestMetricUnits.testConversion(TestMetricUnits.java:29) Results : Tests in error: TestMetricUnits.testConversion:29 NullPointer And the funny part is that, when I run this test from eclipse via JUnit runner everything is fine, I have no NullPointerException and in console I have: Unit.METERS: m Unit.KM: km So the question is: what can be the reason that KM variable in Unit is null (and in the same time METERS is not null)

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  • KD-Trees and missing values (vector comparison)

    - by labratmatt
    I have a system that stores vectors and allows a user to find the n most similar vectors to the user's query vector. That is, a user submits a vector (I call it a query vector) and my system spits out "here are the n most similar vectors." I generate the similar vectors using a KD-Tree and everything works well, but I want to do more. I want to present a list of the n most similar vectors even if the user doesn't submit a complete vector (a vector with missing values). That is, if a user submits a vector with three dimensions, I still want to find the n nearest vectors (stored vectors are of 11 dimensions) I have stored. I have a couple of obvious solutions, but I'm not sure either one seem very good: Create multiple KD-Trees each built using the most popular subset of dimensions a user will search for. That is, if a user submits a query vector of thee dimensions, x, y, z, I match that query to my already built KD-Tree which only contains vectors of three dimensions, x, y, z. Ignore KD-Trees when a user submits a query vector with missing values and compare the query vector to the vectors (stored in a table in a DB) one by one using something like a dot product. This has to be a common problem, any suggestions? Thanks for the help.

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  • zend framework - quickstart application

    - by m gahagan
    I have been attempting to install the 'quickstart' tutorial application on my system. After a considerable amount of frustration - a) because I dont know how it all works andb) mine's a windows (wamp) set-up, I have got as far as setting up the guestbook database successfully and reaching the Checkpoint: Now browse to http://localhost/guestbook. You should see the following in your browser: I get error: Warning: include(C:\wamp\www\quickstart\application/models//GuestbookMapper.php) [function.include]: failed to open stream: No such file or directory in C:\wamp\www\quickstart\library\Zend\Loader\Autoloader\Resource.php on line 176 Warning: include() [function.include]: Failed opening 'C:\wamp\www\quickstart\application/models//GuestbookMapper.php' for inclusion (include_path='C:\wamp\www\quickstart\library;.;C:\wamp\bin\php\php5.3.0\PEAR;C:\wamp\zend\library;C:\wamp\zend\extras\library') in C:\wamp\www\quickstart\library\Zend\Loader\Autoloader\Resource.php on line 176 Fatal error: Class 'Default_Model_GuestbookMapper' not found in C:\wamp\www\quickstart\application\models\Guestbook.php on line 102 Obviously failing to link relevant files is the main issue - First, that 'C:\wamp\www\quickstart\application/models//GuestbookMapper.php' looks wrong to me, but I cant figure out what's creating it. Second, I have a very tenuous grip on the whole file path system and cant tell whether things are wrongly configured. If I could get the guestbook app to function, then I might be able to get a grip on what's going on. As it is, I seem to fix one problem only to find another round the next corner.

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  • SiteMap control based on user roles doesn't works

    - by nCdy
    <siteMapNode roles="*"> <siteMapNode url="~/Default.aspx" title=" Main" description="Main" roles="*"/> <siteMapNode url="~/Items.aspx" title=" Adv" description="Adv" roles="Administrator"/> .... any user can see Adv page. That is a trouble and a qustion : why and how to hide out of role sitenodes. but if I do HttpContext.Current.User.IsInRole("Administrator") it shows me if user in Administrator role or not. web config : <authentication mode="Forms"/> <membership defaultProvider="SqlProvider" userIsOnlineTimeWindow="20"> <providers> <add connectionStringName="FlowWebSQL" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="true" passwordFormat="Hashed" applicationName="/" name="SqlProvider" type="System.Web.Security.SqlMembershipProvider"/> </providers> </membership> <roleManager enabled="true" defaultProvider="SqlProvider"> <providers> <add connectionStringName="FlowWebSQL" name="SqlProvider" type="System.Web.Security.SqlRoleProvider" /> </providers> </roleManager>

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  • RegularExpression-esque search matching Objects in List

    - by Pindatjuh
    I'm currently working on an implementation of the following idea, and I was wondering if there is any literature on this subject. Working with Java, but the principle applies on any language with a decent type-system, I like to implement: matching Objects from a List using a RegularExpression-esque search: So let's say I have a List containing List<Object> x = new ArrayList<Object>(); x.add(new Object()); x.add("Hello World"); x.add("Second String"); x.add(5); // Integer (auto-boxing) x.add(6); // Integer Then I create a "Regular Expression" (not working with a stream of characters, but working with a stream of Objects), and instead of character-classes, I use type-system properties: [String][Integer] And this would match one sublist: {Match["Second String", 5]}. The expression: [String:length()<15] Will match two sublist (each of length 1) containing a String which instance is passing the expression instance.length() < 5: {Match["Hello World"],Match["Second String"]}. [Object][Object] Matches any pair in the List: {Match[Object,"Hello World"],Match["Second String", 5]}, in a streamed manner (no overlapping matches). Ofcourse, my implementation will have grouping, lookahead/lookbehinds and is hierarchical (i.e. matching n elements from Lists in Lists), etc. The above merely illustrates the concept. Is there a name for this principle, and is there literature available on it?

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  • Types of Nested Loops in JAVA

    - by dominoos
    Hi guys. I have a simple question. I have to find out many nested loops as possible in java. I have something like for loop and if statement inside. i know that we can do like if{if{if{if{ something like that too. just need some more idea of more types of nested loops. if you can write down some examples. I'll be very glad. thank you. public class Test { public static void main (String []args) { int i = 0; for(int j = 1; j <= 5; j++) { if(j == 1 || j == 5) { i = 4; } else { i = 1; } for(int x = 0; x < i; x++) { System.out.print("**"); } System.out.println(); } } }

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