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  • To OpenID or not to OpenID? Is it worth it?

    - by Eloff
    Does OpenID improve the user experience? Edit Not to detract from the other comments, but I got one really good reply below that outlined 3 advantages of OpenID in a rational bottom line kind of way. I've also heard some whisperings in other comments that you can get access to some details on the user through OpenID (name? email? what?) and that using that it might even be able to simplify the registration process by not needing to gather as much information. Things that definitely need to be gathered in a checkout process: Full name Email (I'm pretty sure I'll have to ask for these myself) Billing address Shipping address Credit card info There may be a few other things that are interesting from a marketing point of view, but I wouldn't ask the user to manually enter anything not absolutely required during the checkout process. So what's possible in this regard? /Edit (You may have noticed stackoverflow uses OpenID) It seems to me it is easier and faster for the user to simply enter a username and password in a signup form they have to go through anyway. I mean you don't avoid entering a username and password either with OpenID. But you avoid the confusion of choosing a OpenID provider, and the trip out to and back from and external site. With Microsoft making Live ID an OpenID provider (More Info), bringing on several hundred million additional accounts to those provided by Google, Yahoo, and others, this question is more important than ever. I have to require new customers to sign up during the checkout process, and it is absolutely critical that the experience be as easy and smooth as possible, every little bit harder it becomes translates into lost sales. No geek factor outweighs cold hard cash at the end of the day :) OpenID seems like a nice idea, but the implementation is of questionable value. What are the advantages of OpenID and is it really worth it in my scenario described above?

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  • How Can I Find What's Causing My Transaction to Get Promoted?

    - by Damian Powell
    I have web site which serves web services (a mixture of .asmx and WCF) which is mostly using LINQ to SQL and System.Transactions. Occaisionally we see the transaction get promoted to a distributed transaction which causes problems because our web servers are isolated from our databases in such a way that it is not possible for us to use MSDTC. I have configured tracing for System.Transactions by adding the following to my web.config: <system.diagnostics> <sources> <source name="System.Transactions" switchValue="Information"> <listeners> <add name="tx" type="System.Diagnostics.XmlWriterTraceListener" initializeData="tx.log" /> </listeners> </source> </sources> </system.diagnostics> It's very interesting and shows me when the transaction is promoted, but I find that it doesn't really help be discover why. Is there an equivalent tracing mechanism for ADO.NET that will show me when connections are created, including the variables that affect pooling (user, cnn string, transaction scope)?

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  • How Can I Find a List of All Exceptions That a Given Library Function Throws in Python?

    - by b14ck
    Sorry for the long title, but it seems most descriptive for my question. Basically, I'm having a difficult time finding exception information in the official python documentation. For example, in one program I'm currently writing, I'm using the shutil libary's move function: from shutil import move move('somefile.txt', '/tmp/somefile.txt') That works fine, as long as I have write access to /tmp/, there is enough diskspace, and if all other requirements are satisfied. However, when writing generic code, it is often difficult to guarantee those factors, so one usually uses exceptions: from shutil import move try: move('somefile.txt', '/tmp/somefile.txt') except: print 'Move failed for some reason.' I'd like to actually catch the appropriate exceptions thrown instead of just catching everything, but I simply can't find a list of exceptions thrown for most python modules. Is there a way for me to see which exceptions a given function can throw, and why? This way I can make appropriate cases for each exception, eg: from shutil import move try: move('somefile.txt', '/tmp/somefile.txt') except PermissionDenied: print 'No permission.' except DestinationDoesNotExist: print "/tmp/ doesn't exist" except NoDiskSpace: print 'No diskspace available.' Answer points go to whoever can either link me to some relevant documentation that I've somehow overlooked in the official docs, or provide a sure-fire way to figure out exactly which exceptions are thrown by which functions, and why. Thanks!

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  • Updating a listitem in an ASPX page in SharePoint Designer

    - by Andy
    Hey All, Right now I'm using SharePoint Designer to create a new aspx page. I am using a data view to display information from a list. One of the fields in the list is a choice field. I was wondering if there was anyway that I could display all of the other fields but allow one field in the list to be edited on the page without adding an edit link. Ideally, I would like a user to go in and be able to edit a field value (hopefully in a drop down list) within a data view without being redirected to the list or a form. I'm thinking there is a way to do this through javascript to embed inside the HTML or through a workflow of some sort. I'm new to javascript and don't know how to do this. I have tried to insert a drop down list and provide a data source for it but it will only show all of the field values in the list. Thus, I am unable to display the choice options, show the current value in the listitem and edit/update the listitem. Hopefully this makes sense. Can anyone help me out here? Thanks a lot, Andy

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  • Determine target architecture of binary file in Linux (library or executable)

    - by Fernando Miguélez
    We have an issue related to a Java application running under a (rather old) FC3 on a Advantech POS board with a Via C3 processor. The java application has several compiled shared libs that are accessed via JNI. Via C3 processor is suppossed to be i686 compatible. Some time ago after installing Ubuntu 6.10 on a MiniItx board with the same processor I found out that the previous statement is not 100% true. The Ubuntu kernel hanged on startup due to the lack of some specific and optional instructions of the i686 set in the C3 processor. These instructions missing in C3 implementation of i686 set are used by default by GCC compiler when using i686 optimizations. The solution in this case was to go with a i386 compiled version of Ubuntu distribution. The base problem with the Java application is that the FC3 distribution was installed on the HD by cloning from an image of the HD of another PC, this time an Intel P4. Afterwards the distribution needed some hacking to have it running such as replacing some packages (such as the kernel one) with the i383 compiled version. The problem is that after working for a while the system completely hangs without a trace. I am afraid that some i686 code is left somewhere in the system and could be executed randomly at any time (for example after recovering from suspend mode or something like that). My question is: Is there any tool or way to find out at what specific architecture is an binary file (executable or library) aimed provided that "file" does not give so much information?

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  • Spring security - same page to deliver different content based on user role

    - by Ramesh
    Hello, i tried to search for any previous post related to my issue but couldnt find any. I have a scenario where in page handles 3 different scenarios and one of them not working. This page returns different content depending on if the user is authenticated or anonymous. localhost:8080/myApp/muUrl?test=authenticatedContent - used for Scenario 1 & 2 localhost:8080/myApp/muUrl?test=anonymousContent - used for Scenario 3 Scenario: 1) Authenticated user accesing the page url - the user gets displayed correct information. Works fine 2) Anonymous user accesing page URL with parameters that requires authentication - If anonymous, there is second level of check on the content they are accessing. for example, based on the GET parameters, there is custom logic to determine if the user has to be authenticated. In which case the page gets redirected to login page (WORKS fine). 3) Anonymous user accessing page URL with parameters that doesnt need authentication - in this case i get the SAvedRequest and redirect to the URL which is taking me to an infinite loop. Am i missing something very obvious or is there a way in AuthenticationProcessFilterEntryPoint to say "DON'T redirect to LOGIN page but process it" ? thanks.

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  • Where do I attach the StoreKit delegate and observer in a Cocos2d App?

    - by Jeff B
    I have figured out how all of the StoreKit stuff works and have actually tested working code... however, I have a problem. I made my "store" layer/scene the SKProductsRequestDelegate. Is this the correct thing to do? I get the initial product info like so: SKProductsRequest *productRequest = [[SKProductsRequest alloc] initWithProductIdentifiers: productIDs]; [productRequest setDelegate: self]; [productRequest start]; The problem is that if I transition to a new scene when a request is in progress, the current layer is retained by the productRequest. This means that touches on my new scene/layer are handled by both the new layer and the old layer. I could cancel the productRequest when leaving the scene, but: I do not know if it is in progress at that point. I cannot release it because it may or may not have been released by the request delegates. There has got to be a better way to do this. I could make the delegate a class external to the current layer, but then I do not know how to easily update the layer with the product information when the handler is called.

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  • Created files on Archos 5 invisible on Windows Xp

    - by user352042
    I am fairly new to Android and this is my first post so I apologise in advance if I am breaking protocol or posting to the wrong board. Please feel free to move this post to somewhere more appropriate if required. I am developing for the 160 Gb Archos 5 Internet tablet. Not ideal as a development platform I know, but customer requirements mean we have no choice. It is running Android 1.6. I have updated the device firmware to the most recent available. Updating the version of Android is not an option at this point. Part of my app's requirement is to write information out to .txt files on the external storage directory so that these can be copied over the USB connection to a Windows XP PC using the Mobile media device (MTP) mode. I have followed all instructions I have come across carefully, eg I check that the storage is available using the technique described at http://developer.android.com/guide/topics/data/data-storage.html#filesExternal. However, althoug the files are created succesfully on the device (I can browse them and open them using the device's File Explorer - they are fine), when I connect the device to a Windows XP computer none of the directories or files I created appear and the size of their parent files suggest they do not exist. I have tried running over the ADB, checked logcat, tried a (signed) release version and even written a second test application which just creates a folder (this behaves the same, ie it creates the folder but this is not visible in Windows Explorer) - nothing anywhere gives me any suggestion as to what the problem might be. If anyone has heard of this before or has any ideas as to what else | could try to fix it please get in touch! We do not have any other devices to test on at the moment, although I hope to remedy this soon, customer permitting.

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  • Meta tag depending of selected language and title

    - by lena
    Hi, I'm aware about Google ignore most of the time, meta tag and use content. (This is not the point here) I'm working on an existing web site, not created by me. I need a quick solution, I guess with variables. The website construction: (no known template system) index.html which is presentation page with language selection index.php which embeding menu, content, footer several content pages that are embedded by index.php What I need to do only for those 2 pages welcome_en.html and welcome_fr.html (these pages are embedded so no header possible on these page) to have different page title (browser title) and different META tag. Any solution is welcome Thanks extra information Language detection on index.php: <?php $lang = $_GET['lang']; $page = $_GET['page']; if ($_GET['page'] == "" || !$_GET['page']) { $page = "welcome"; } if ($_GET['lang'] == "" || !$_GET['lang']) { $lang = "_fr"; } ? <td><img src="images/ban02<?php echo "$lang" ?>.jpg" width="531" height="60" <?php if ($_GET['lang'] == "_fr" || $_GET['lang'] == "" || !$_GET['lang']) { echo "alt='text'";} else if ($_GET['lang'] == "_en") {echo "alt='text'"; } ?>></td> for the embeded menu, footer ect like this one <?php include "menu.php"; ?> for the embedded content <?php //echo "$page$lang.html"; $lang = preg_replace('/[^a-z0-9_ ]/i', '', $_GET['lang']); $page = preg_replace('/[^a-z0-9_ ]/i', '', $_GET['page']); include $page . $lang . ".html"; ?>

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  • What database strategy to choose for a large web application

    - by Snoopy
    I have to rewrite a large database application, running on 32 servers. The hardware is up to date, each machine has two quad core Xeon and 32 GByte RAM. The database is multi-tenant, each customer has his own file, around 5 to 10 GByte each. I run around 50 databases on this hardware. The app is open to the web, so I have no control on the load. There are no really complex queries, so SQL is not required if there is a better solution. The databases get updated via FTP every day at midnight. The database is read-only. C# is my favourite language and I want to use ASP.NET MVC. I thought about the following options: Use two big SQL servers running SQL Server 2012 to serve the 32 servers with data. On the 32 servers running IIS hosting providing REST services. Denormalize the database and use Redis on each webserver. Use booksleeve as a Redis client. Use a combination of SQL Server and Redis Use SQL Server 2012 together with Hadoop Use Hadoop without SQL Server What is the best way for a read-only database, to get the best performance without loosing maintainability? Does Map-Reduce make sense at all in such a scenario? The reason for the rewrite is, the old app written in C++ with ISAM technology is too slow, the interfaces are old fashioned and not nice to use from an website, especially when using ajax. The app uses a relational datamodel with many tables, but it is possible to write one accerlerator table where all queries can be performed on, and all other information from the other tables are possible by a simple key lookup.

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  • Ember Data Sycn - LocalStorage+REST+RealTime+Online/Offline

    - by Miguel Madero
    We have a combination of requirements in terms o data access. Pre-load some reference data. We need reference data to survive browser restarts instead of just living in memory to avoid loading it all the time. I'm currently using the LocalStorageAdapter for that. Once we have it, we would like to sync changes (polling or using Socket.IO in the background and updating the LocalStorage could do the trick) There're other models that are more transactional, where we would need to directly go to the Server and get/save them. It would be nice to use something like the RESTAdapter for that. Lastly, there're some operations that should work off-line and changes should be synced later. To make it more concrete: * We pre-load vendor and "favorite products" into Local Storage. We work offline with those. * We need to sync server changes to vendor and product information. * If they search the full catalog, that requires them to be online. * When offline, we need to allow users to add something to their cart or even submit and order. We would like to queue this action and submit it when they have an Internet Connection. So a few questions are derived from this: * Is there a way to user RESTAdapter in combination with LocalStorage? * Is there some Socket.IO support? (Happy to do this part manually) * Is there Queueing support? Ideally at the Ember-Data level. I know we will have to do a lot of this manually and pull together the different lego pieces, but I wanted to ask for some perspective from experience Ember devs.

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  • Javascript storing properties and functions in variables

    - by richard
    Hello, I'm having trouble with my programming style and I hope to get some feedback here. I recently bought Javascript: The Good Parts and while I find this a big help, I'm still having trouble designing this application. Especially when it comes to writing function and methods. Example: I have a function that let's the user switches games in my app. This function updates game-specific information in the current view. var games = { active: Titanium.App.Properties.getString('active_game'), gameswitcher_positions: { 'Game 1': 0, 'Game 2': 1, 'Game 3': 2, 'Game 4': 3, 'Game 5': 4 }, change: function(game) { if (active_game !== game) { gameswitcher.children[this.gameswitcher_positions[this.active]].backgroundImage = gameswitcher.children[this.gameswitcher_positions[this.active]].backgroundImage.replace('_selected', ''); gameswitcher.children[this.gameswitcher_positions[game]].backgroundImage = gameswitcher.children[this.gameswitcher_positions[game]].backgroundImage.replace('.png', '_selected.png'); events.update(game); this.active = game; } }, init: function() { gameswitcher.children[this.gameswitcher_positions[this.active]].backgroundImage = gameswitcher.children[this.gameswitcher_positions[this.active]].backgroundImage.replace('.png', '_selected.png'); events.update(this.active); } }; gameswitcher is a container view which contains buttons to switch games. I am not satisfied with this approach but I cannot think of a better one. Should I place the gameswitcher_positions outside of the variable in a seperate variable instead of as a property? And what about the active game? Please give me feedback, what am I doing wrong?

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  • PHP does not store all variables in session

    - by Flurin Juvalta
    Dear all I'm assigning session variables by filling the $_SESSION - Array throughout my script. My problem is, that for some reason not all variables are available in the session. here is a shortened version of my code for explaining this issue: session_start(); print_r($_SESSION); $_SESSION['lang'] = 'de'; $_SESSION['location_id'] = 11; $_SESSION['region_id'] = 1; $_SESSION['userid'] = 'eccbc87e4b5ce2fe28308fd9f2a7baf3'; $_SESSION['hash'] = 'dce57f1e3bc6fba32afab93b0c38b662'; print_r($_SESSION); first call prints something like this: Array ( ) Array ( [lang] => de [location_id] => 11 [region_id] => 1 [userid] => eccbc87e4b5ce2fe28308fd9f2a7baf3 [hash] => dce57f1e3bc6fba32afab93b0c38b662 ) the second call prints: Array ( [lang] => de [location_id] => 11 [region_id] => 1 ) Array ( [lang] => de [location_id] => 11 [region_id] => 1 [userid] => eccbc87e4b5ce2fe28308fd9f2a7baf3 [hash] => dce57f1e3bc6fba32afab93b0c38b662 ) As you can see, the important login information is not stored in the session. Does anybody has an idea what could be wrong with my session? Thanks for your answers!

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  • What is best practice about having one-many hibernate

    - by Patrick
    Hi all, I believe this is a common scenario. Say I have a one-many mapping in hibernate Category has many Item Category: @OneToMany( cascade = {CascadeType.ALL},fetch = FetchType.LAZY) @JoinColumn(name="category_id") @Cascade( value = org.hibernate.annotations.CascadeType.DELETE_ORPHAN ) private List<Item> items; Item: @ManyToOne(targetEntity=Category.class,fetch=FetchType.EAGER) @JoinColumn(name="category_id",insertable=false,updatable=false) private Category category; All works fine. I use Category to fully control Item's life cycle. But, when I am writing code to update Category, first I get Category out from DB. Then pass it to UI. User fill in altered values for Category and pass back. Here comes the problem. Because I only pass around Category information not Item. Therefore the Item collection will be empty. When I call saveOrUpdate, it will clean out all associations. Any suggestion on what's best to address this? I think the advantage of having Category controls Item is to easily main the order of Item and not to confuse bi-directly. But what about situation that you do want to just update Category it self? Load it first and merge? Thank you.

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  • Ways of breaking down SQL transactional/call data into reports -- 'square data'?

    - by RizwanK
    I've got a large database of call-traffic information (although the question could be answered with any generic data set.) For instance, a row contains : call endpoint server (endpoint_name) call endpoint status (sip_disconnect_reason) call destination (destination) call completed (duration) [duration 0 is completed] call account group (account_group) It's pretty easy to run SQL reports against the data, i.e. select count(*), endpoint_name from calls where duration0 group by endpoint_name select count(*),destination from calls where blah group by destination I've been calling this filtering or breakdown reports (I get the number of calls per carrier, etc.). Add another breakdown, and you've got two breakdowns, a la select count(*), endpoint_name, sip_disconnect_reason from calls where duration=0 group by endpoint_name, sip_disconnect_reason Of course, if you keep adding breakdowns, you end up making super-large reports and slicing your data so thin that you can't extract any trends from it. So my question is this : Is there a name for this sort of method of report writing? (I've heard words like squares, slicing and breakdown reports applied to them) --- I'm looking for a Python/Reporting toolkit that I can use to make these easier to generate for my end users. aside : Are there other ways of representing transactional data that might be useful rather than the above method? Thanks,

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  • wxPython - ListCrtl and SQLite3

    - by Dunwitch
    I'm trying to get a SQLite3 DB to populate a wx.ListCrtl. I can get it to print to stdout/stderr without any problem. I just can't seem to figure out how to display the data in the DataWindow/DataList? I'm sure I've made some code mistakes, so any help is appreciated. Main.py import wx import wx.lib.mixins.listctrl as listmix from database import * import sys class DataWindow(wx.Frame): def __init__(self, parent = None): wx.Frame.__init__(self, parent, -1, 'DataList', size=(640,480)) self.win = DataList(self) self.Center() self.Show(True) class DataList(wx.ListCtrl, listmix.ListCtrlAutoWidthMixin, listmix.ColumnSorterMixin): def __init__(self, parent = DataWindow): wx.ListCtrl.__init__( self, parent, -1, style=wx.LC_REPORT|wx.LC_VIRTUAL|wx.LC_HRULES|wx.LC_VRULES) #building the columns self.InsertColumn(0, "Location") self.InsertColumn(1, "Address") self.InsertColumn(2, "Subnet") self.InsertColumn(3, "Gateway") self.SetColumnWidth(0, 100) self.SetColumnWidth(1, 150) self.SetColumnWidth(2, 150) self.SetColumnWidth(3, 150) class MainWindow(wx.Frame): def __init__(self, parent = None, id = -1, title = "MainWindow"): wx.Frame.__init__(self, parent, id, title, size = (800,600), style = wx.DEFAULT_FRAME_STYLE ^ (wx.RESIZE_BORDER)) # StatusBar self.CreateStatusBar() # Filemenu filemenu = wx.Menu() # Filemenu - About menuitem = filemenu.Append(-1, "&About", "Information about this application") self.Bind(wx.EVT_MENU, self.onAbout, menuitem) #Filemenu - Data menuitem = filemenu.Append(-1, "&Data", "Get data") self.Bind(wx.EVT_MENU, self.onData, menuitem) # Filemenu - Seperator filemenu.AppendSeparator() #Filemenu - Exit menuitem = filemenu.Append(-1, "&Exit", "Exit the application") self.Bind(wx.EVT_MENU, self.onExit, menuitem) # Menubar menubar = wx.MenuBar() menubar.Append(filemenu, "&File") self.SetMenuBar(menubar) # Show self.Show(True) self.Center() def onAbout(self, event): pass def onData(self, event): DataWindow(self) callDb = Database() sql = "SELECT rowid, address, subnet, gateway FROM pod1" records = callDb.select(sql) for v in records: print "How do I get the records on the DataList?" #print "%s%s%s" % (v[1],v[2],v[3]) #for v in records: #DataList.InsertStringItem("%s") % (v[0], v[1], v[2]) def onExit(self, event): self.Close() self.Destroy() def onSave(self, event): pass if __name__ == '__main__': app = wx.App() frame = MainWindow(None, -1) frame.Show() app.MainLoop() database.py import os import sqlite3 class Database(object): def __init__(self, db_file="data/data.sqlite"): database_allready_exists = os.path.exists(db_file) self.db = sqlite3.connect(db_file) if not database_allready_exists: self.setupDefaultData() def select(self,sql): cursor = self.db.cursor() cursor.execute(sql) records = cursor.fetchall() cursor.close return records def insert(self,sql): newID = 0 cursor = self.db.cursor() cursor.execute(sql) newID = cursor.lastrowid self.db.commit() cursor.close() return newID def save(self,sql): cursor = self.db.cursor() cursor.execute(sql) self.db.commit() cursor.close() def setupDefaultData(self): pass

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  • How to start with entity framework and service oriented architecture?

    - by citronas
    At work I need to create a new web application, that will connection to an MySql Database. (So far I only have expercience with Linq-To-Sql classes and MSSQL Servers.) My superior tells me to use the entity framework (he probably refers to Linq-To-Entity) and provide everything as a service based architecture. Unfortunatly nobody at work has experience with that framework and with a real nice server oriented architecture. (till now no customer wanted to pay for architecture that he can't see. This speficic project I'm leading will be long-term, meaning multiple years, so it would be best to design it the way, that multiple targetting plattforms like asp.net, c# wpf, ... could use it) For now, the main target plattform is ASP.net So I do have the following questions: 1) Where can I read best what's really behind service oriented architecture (but for now beginner tutorials work fine as well) and how to do it in best practise? 2) So far I can't seem a real difference between Linq-To-Sql classes and the information I've google so far on the 'entity framework'. So, whats the difference? Where do I find nice tutorials for it. 3) Is there any difference in the entity framework regarding the database server (MSSQL or MySQL). If not, does that mean that code snipperts I will stumble across will word database independent? 4) I do you Visual Studio 2010. Do I have to regard something specific?

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  • When I get the Force Close dialog, I have a Report button. Where did it come from?

    - by BenTobin
    I feel a little bit silly asking this, but I haven't been able to find any answers on my own. My Force Close dialog has a "Report" button. I think it's a great idea, and I wish everyone had it. At first, I thought it must be something I turned on without realizing it, but not only can't I find any setting that I might have touched, I also can't find any reference to this button existing on the Internet. I have a Droid, and I know 4 other people with Droids, and they say they don't have the option to report Force Closes. Am I special? Am I just missing something? The "report" button has been there for at least a few weeks now. When I use the Report button, I get a screen with a "feedback" field and a checkbox for "Include system data". Below that , it says "Information from feedback reports will be shown to the developer of the application." Under that are Preview and Send buttons. As a developer, I've never received one of these reports. I'd try to send a report to myself, but it seemingly only shows the button for apps installed from the market, and I don't know of a way to crash my production app. I suppose I could publish a simple crashing app just to try it out, but I thought I'd ask you folks first. Edit: You can view screenshots here: http://bentobin.com/crashReportImages/

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  • Where can I find BLAS example code (in Fortran)?

    - by Feynman
    I have been searching for decent documentation on blas, and I have found some 315 pages of dense material that ctrl-f does not work on. It provides all the information regarding what input arguments the routines take, but there are a LOT of input arguments and I could really use some example code. I am unable to locate any. I know there has to be some or no one would be able to use these libraries! Specifically, I use ATLAS installed via macports on a mac osx 10.5.8 and I use gfortran from gcc 4.4 (also installed via macports). I am coding in Fortran 90. I am still quite new to Fortran, but I have a fair amount of experience with mathematica, matlab, perl, and shell scripting. I would like to be able to initialize and multiply a dense complex vector by a dense symmetric (but not hermitian) complex matrix. The elements of the matrix are defined through a mathematical function of the indices--call it f(i,j). Could anyone provide some code or a link to some code?

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  • How to Treat Race Condition of Session in Web Application?

    - by Morgan Cheng
    I was in a ASP.NET application has heavy traffic of AJAX requests. Once a user login our web application, a session is created to store information of this user's state. Currently, our solution to keep session data consistent is quite simple and brutal: each request needs to acquire a exclusive lock before being processed. This works fine for tradition web application. But, when the web application turns to support AJAX, it turns to not efficient. It is quite possible that multiple AJAX requests are sent to server at the same time without reloading the web page. If all AJAX requests are serialized by the exclusive lock, the response is not so quick. Anyway, many AJAX requests that doesn't access same session variables are blocked as well. If we don't have a exclusive lock for each requests, then we need to treat all race condition carefully to avoid dead lock. I'm afraid that would make the code complex and buggy. So, is there any best practice to keep session data consistent and keep code simple and clean?

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  • C++ Declarative Parsing Serialization

    - by Martin York
    Looking at Java and C# they manage to do some wicked processing based on special languaged based anotation (forgive me if that is the incorrect name). In C++ we have two problems with this: 1) There is no way to annotate a class with type information that is accessable at runtime. 2) Parsing the source to generate stuff is way to complex. But I was thinking that this could be done with some template meta-programming to achieve the same basic affect as anotations (still just thinking about it). Like char_traits that are specialised for the different types an xml_traits template could be used in a declaritive way. This traits class could be used to define how a class is serialised/deserialized by specializing the traits for the class you are trying to serialize. Example Thoughs: template<typename T> struct XML_traits { typedef XML_Empty Children; }; template<> struct XML_traits<Car> { typedef boost::mpl::vector<Body,Wheels,Engine> Children; }; template<typename T> std::ostream& Serialize(T const&) { // my template foo is not that strong. // but somthing like this. boost::mpl::for_each<typename XML_Traits<T>::Children,Serialize>(data); } template<> std::ostream& Serialize<XML_Empty>(T const&) { /* Do Nothing */ } My question is: Has anybody seen any projects/decumentation (not just XML) out there that uses techniques like this (template meta-programming) to emulate the concept of annotation used in languges like Java and C# that can then be used in code generation (to effectively automate the task by using a declaritive style). At this point in my research I am looking for more reading material and examples.

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  • Resource mapping in a Ruby on Rails URL (RESTful API)

    - by randombits
    I'm having a bit of difficulty coming up with the right answer to this, so I will solicit my problem here. I'm working on a RESTFul API. Naturally, I have multiple resources, some of which consist of parent to child relationships, some of which are stand alone resources. Where I'm having a bit of difficulty is figuring out how to make things easier for the folks who will be building clients against my API. The situation is this. Hypothetically I have a 'Street' resource. Each street has multiple homes. So Street :has_many to Homes and Homes :belongs_to Street. If a user wants to request an HTTP GET on a specific home resource, the following should work: http://mymap/streets/5/homes/10 That allows a user to get information for a home with the id 10. Straight forward. My question is, am I breaking the rules of the book by giving the user access to: http://mymap/homes/10 Technically that home resource exists on its own without the street. It makes sense that it exists as its own entity without an encapsulating street, even though business logic says otherwise. What's the best way to handle this?

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  • Magento 1.4 - how to show html on product view?

    - by Sam
    Hi All The new version of Magento, 1.4, has it's own WYSIWYG editor, which can be enabled for any product attribute. However, if it is enabled, say for the additional info attribute, if you view the product page the html will be escaped, so you see all the tags (< p , < ul etc). If you change the following in template/catalog/product/view.phtml, you can get the "Quick Overview" and "Additional Information" sections to correctly show the html: <?php echo nl2br($this->htmlEscape($_product->getShortDescription())) ?> to <?php echo $_product->getShortDescription() ?> However, the additional info section is added via template/catalog/product/view/attributes.phtml using the following line, and I can't figure out how to get it to show the html correctly: <?php echo $_helper->productAttribute($_product, $_data['value'], $_data['code']) ?> This references Mage_Catalog_Block_Product_View_Attributes, and if I go to that file and change the following, it works: $value = $this->htmlEscape($value); to $value = value; But is there anyway to do this without overiding this core file with a local version?

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  • How can I create an Image in GDI+ from a Base64-Encoded string in C++?

    - by Schnapple
    I have an application, currently written in C#, which can take a Base64-encoded string and turn it into an Image (a TIFF image in this case), and vice versa. In C# this is actually pretty simple. private byte[] ImageToByteArray(Image img) { MemoryStream ms = new MemoryStream(); img.Save(ms, System.Drawing.Imaging.ImageFormat.Tiff); return ms.ToArray(); } private Image byteArrayToImage(byte[] byteArrayIn) { MemoryStream ms = new MemoryStream(byteArrayIn); BinaryWriter bw = new BinaryWriter(ms); bw.Write(byteArrayIn); Image returnImage = Image.FromStream(ms, true, false); return returnImage; } // Convert Image into string byte[] imagebytes = ImageToByteArray(anImage); string Base64EncodedStringImage = Convert.ToBase64String(imagebytes); // Convert string into Image byte[] imagebytes = Convert.FromBase64String(Base64EncodedStringImage); Image anImage = byteArrayToImage(imagebytes); (and, now that I'm looking at it, could be simplified even further) I now have a business need to do this in C++. I'm using GDI+ to draw the graphics (Windows only so far) and I already have code to decode the string in C++ (to another string). What I'm stumbling on, however, is getting the information into an Image object in GDI+. At this point I figure I need either a) A way of converting that Base64-decoded string into an IStream to feed to the Image object's FromStream function b) A way to convert the Base64-encoded string into an IStream to feed to the Image object's FromStream function (so, different code than I'm currently using) c) Some completely different way I'm not thinking of here. My C++ skills are very rusty and I'm also spoiled by the managed .NET platform, so if I'm attacking this all wrong I'm open to suggestions.

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  • IIS to SQL Server kerberos auth issues

    - by crosan
    We have a 3rd party product that allows some of our users to manipulate data in a database (on what we'll call SvrSQL) via a website on a separate server (SvrWeb). On SvrWeb, we have a specific, non-default website setup for this application so instead of going to http://SvrWeb.company.com to get to the website we use http://application.company.com which resolves to SvrWeb and the host headers resolve to the correct website. There is also a specific application pool set up for this site which uses an Active Directory account identity we'll call "company\SrvWeb_iis". We're setup to allow delegation on this account and to allow it to impersonate another login which we want it to do. (we want this account to pass along the AD credentials of the person signed into the website to SQL Server instead of a service account. We also set up the SPNs for the SrvWeb_iis account via the following command: setspn -A HTTP/SrvWeb.company.com SrvWeb_iis The website pulls up, but the section of the website that makes the call to the database returns the message: Cannot execute database query. Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON'. I thought we had the SPN information set up correctly, but when I check the security event log on SrvWeb I see entries of my logging in, but it seems to be using NTLM and not kerberos: Logon Type: 3 Logon Process: NtLmSsp Authentication Package: NTLM Any ideas or articles that cover this setup in detail would be extremely appreciated! If it helps, we are using SQL Server 2005, and both the web and SQL servers are Windows 2003.

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