Search Results

Search found 37650 results on 1506 pages for 'files'.

Page 359/1506 | < Previous Page | 355 356 357 358 359 360 361 362 363 364 365 366  | Next Page >

  • Update Google Sitemap for Mobile

    - by dimo414
    I have a series of utilities to generate Google sitemaps for my whole site. These files are massive, and slow to build. We want to start telling Google these pages are mobile-crawl-able too, by adding them to mobile sitemaps, but the documentation is unclear if I need to specify physically different files for my mobile URLs than for my normal ones. If this is my current sitemap: <?xml version="1.0" encoding="UTF-8" ?> <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"> <url> <loc>http://mobile.example.com/article100.html</loc> </url> </urlset> Can I simply change it to: <?xml version="1.0" encoding="UTF-8" ?> <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:mobile="http://www.google.com/schemas/sitemap-mobile/1.0"> <url> <loc>http://mobile.example.com/article100.html</loc> <mobile:mobile/> </url> </urlset> Or do I need to create new files with the additional markup, alongside my existing files?

    Read the article

  • Script/tool to import series of snapshots, each being a new edition, into GIT, populating source tree?

    - by Rob
    I've developed code locally and taken a fairly regular snapshot whenever I reach a significant point in development, e.g. a working build. So I have a long-ish list of about 40 folders, each folder being a snapshot e.g. in ascending date YYYYMMDD order, e.g.:- 20100523 20100614 20100721 20100722 20100809 20100901 20101001 20101003 20101104 20101119 20101203 20101218 20110102 I'm looking for a script to import each of these snapshots into GIT. The end result being that the latest code is the same as the last snapshot, and other editions are accessible and are as numbered. Some other requirements: that the latest edition is not cumulative of the previous snapshots, i.e., files that appeared in older snapshots but which don't appear in later ones (e.g. due to refactoring etc.) should not appear in the latest edition of the code. meanwhile, there should be continuity between files that do persist between snapshots. I would like GIT to know that there are previous editions of these files and not treat them as brand new files within each edition. Some background about my aim: I need to formally revision control this work rather than keep local private snapshot copies. I plan to release this work as open source, so version controlling would be highly recommended I am evaluating some of the current popular version control systems (Subversion and GIT) BUT I definitely need a working solution in GIT as well as subversion. I'm not looking to be persuaded to use one particular tool, I need a solution for each tool I am considering. (I haved posted an answer separately for each tool so separate camps of folks who have expertise in GIT and Subversion will be able to give focused answers on one or the other). The same but separate question for Subversion: Script/tool to import series of snapshots, each being a new revision, into Subversion, populating source tree?

    Read the article

  • HTML5 media loading sometimes suspends or aborts: misconfigured Apache?

    - by Joan Botella
    Recently, some code that has been working fine for months started to run unexpectedly. That code is just a media files loading JavaScript function, that uses jQuery. It's pretty long, but in essence it is like this: var $audio=$('<audio>'); $audio.on('canplaythrough',function(e){ $audio[0].play(); }); $audio.attr('src','song.ogg'); Basically, the file only loads sometimes, and sometimes stops loading with a suspend or even an abort event. I have uploaded a little testing HTML to http://www.joanbotella.com/tests/loading , where you can see what's happening. You can download the test files from http://www.joanbotella.com/tests/loading/loadingTest.zip for local testing. I have just checked that opening the test index.html file directly into Firefox, and not through my localhost Apache server, makes the audio files perfectly playable. So, I assume, my hosting and I have the Apache server misconfigured for serving media files. My software versions are: Apache 2.2.22-1ubuntu1.7 , Mozilla Firefox 31.0 , Chromium 36.0.1985.125 and jQuery 1.11.0. Can you help me? Thanks in advance!

    Read the article

  • Defining a function that is both a generator and recursive [on hold]

    - by user96454
    I am new to python, so this code might not necessarily be clean, it's just for learning purposes. I had the idea of writing this function that would display the tree down the specified path. Then, i added the global variable number_of_py to count how many python files were in that tree. That worked as well. Finally, i decided to turn the whole thing into a generator, but the recursion breaks. My understanding of generators is that once next() is called python just executes the body of the function and "yields" a value until we hit the end of the body. Can someone explain why this doesn't work? Thanks. import os from sys import argv script, path = argv number_of_py = 0 lines_of_code = 0 def list_files(directory, key=''): global number_of_py files = os.listdir(directory) for f in files: real_path = os.path.join(directory, f) if os.path.isdir(real_path): list_files(real_path, key=key+' ') else: if real_path.split('.')[-1] == 'py': number_of_py += 1 with open(real_path) as g: yield len(g.read()) print key+real_path for i in list_files(argv[1]): lines_of_code += i print 'total number of lines of code: %d' % lines_of_code print 'total number of py files: %d' % number_of_py

    Read the article

  • Unicode license

    - by Eric Grange
    Unicode Terms of use (http://www.unicode.org/copyright.html) state that any software that uses their data files (or a modification of it) should carry the Unicode license references. It seems to me that most Unicode libraries have functions to check if a character is a digit, a letter, a symbol, etc. ans so will contain a modification of the Unicode Data Files (usually in the form of tables). Does that mean the license applies and all applications that use such Unicode libraries should carry the license? I've checked around, and it appears very few Unicode software do carry the license, though arguable most of those that didn't carry the license were from companies that were members of the Unicode consortium (do they get license exemption?). Some (f.i. Mozilla) are only "Liaison Members", and while their software do not carry the license (AFAICT), they do obviously rely on data derived from those data files. Is Mozilla in breach of the license? Should we carry the license in all apps that include any form of advanced Unicode support? (ie. are bound to rely on the Unicode data files) Or is there some form of broad exemption? (since very very few software out there carries the license)

    Read the article

  • Is chroot the right choice for my use case?

    - by Anthony
    Backstory: I am working on setting up a MineCraft server and want to allow admins to have ssh access to the MineCraft server console and appropriate mc server files, but not the whole system. The console provided by the minecraft server is only available to the user that launched the process. In addition, the admins will need terminal access to some basic cli tools such as wget, cp, mv, rm, and a text editor. Plan: I have already setup the ssh aspect of things, requiring pre-shared keys and whatnot. Setup a jailed environment in which all user activity will be contained. Setup user accounts. - The first user account will be the minecraft user. The minecraft user will start the MC server in a multiuser screen session and allow the other admins to attach to it. - Subsequent users should have their own /home directory for normal usage. Setup acl for the appropriate files to allow each user to edit the mc server files. No one will be doing system updates, nor will anyone be installing any programs, so I'll be the only user with sudo. The Issues: I don't want the ssh users to have access to the whole system. Users will still need to use wget or curl to update the mc server files. Is chroot the right tool for this use case, or is there something more appropriate for the job? I have no experience setting up a chroot environment and have found several tools to aid in this process. Jailkit seems to be the most robust, but it's not in the standard repos.

    Read the article

  • ASP.NET Webforms developers and web designers: how to interact?

    - by just_name
    I'm an ASP.NET Webforms developer, and I face some problems when I deal with designers. Designers always complain about the asp.net server controls. They'd rather just have an html file and create css files along with the required images to go with those. Sometimes, if the design phase is done in advance, I get html files with related css files, but then we face many problems integrating the design with the aspx files (sever controls an telerik controls ... etc). What I want to ask about is: How do I overcome these problems? The designers prefer php- and mvc developers because of the problems with .net server controls. I need to know how to interact with the designers in the correct way. Are there any tools or applications to provide the designers with the rendered (html page) of the .aspx pages? By that I mean the page in runtime rather than the aspx in Visual Studio. They do use Web Expression but they want the rendered page in html as well.

    Read the article

  • Updating Google sitemap for mobile

    - by dimo414
    I have a series of utilities to generate Google sitemaps for my whole site. These files are massive, and slow to build. We want to start telling Google these pages are mobile-crawl-able too, by adding them to mobile sitemaps, but the documentation is unclear if I need to specify physically different files for my mobile URLs than for my normal ones. If this is my current sitemap: <?xml version="1.0" encoding="UTF-8" ?> <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"> <url> <loc>http://mobile.example.com/article100.html</loc> </url> </urlset> Can I simply change it to: <?xml version="1.0" encoding="UTF-8" ?> <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:mobile="http://www.google.com/schemas/sitemap-mobile/1.0"> <url> <loc>http://mobile.example.com/article100.html</loc> <mobile:mobile/> </url> </urlset> Or do I need to create new files with the additional markup, alongside my existing files?

    Read the article

  • How to sell logistical procedures that require less time to perform but more finesse?

    - by foampile
    I am working with a group where part of the responsibilities is managing a certain set of configuration files which, of course, have the same skeleton/structure across different environments but different values (like server, user, this setting, that setting etc.). Pretty classic scenario... The problem is that everyone just goes and modifies final, environment-specific files and basically repeats the work for every environment. Personally, I am offended to have to peform repeatable, mundane tasks in this day and age when we have technologies to automate it all. So I devised a very simple procedure of abstracting the files into templates, stubbing env-specific values with parameters and then wrote a simple Perl script that, given a template and an environment matrix with env-specific values for each param, produces the final file. So this is nothing special, cutting-edge or revolutionary -- I am pretty sure that 20 years ago efficient places did their CM like that. However, that requires that changes are made at the template level and then distributed across different environments using the script and not making changes in the final environment-specific files. This is where I am encountering resentment as they feel "comfortable" doing it their old, manual, repeated labor way. Personally, I don't have a problem with them working hard rather than smart but the problem is when I have to build on top of someone else's changes, I have to merge their changes into my template from a specific file, which takes time and is grueling. So my question is how to go about selling my method, which makes it so much faster in an environment that is resentful to change and where most things have to be done at the level of the least competent team member?

    Read the article

  • How to create shared home directories across multiple computers?

    - by Joe D
    I know there are ways to share a folder across computers making it easy to move files. But I was wondering how one would setup a single login which lets you access the same files regardless of which machine you login on? What I would like is something similar to something you would see in a college campus where students login on machines in the lab and see their files regardless of which machine they use. I know there are server involved here. I have a need to create this on a smaller scale where we have a few computers available (and one of these could act as the server if needed and host the files) that every one shares. Note, the specific install of software might be different on each computer but the login and OS are the same. Since some computers have additional capability that our group members will need to use at rotating schedules (software licenses or hardware components, etc.). I have not done this before, so I would appreciate detailed instructions if possible or a reference to a guide that describes this. Thanks in advance.

    Read the article

  • What do you do to balance the upper or lower case style to name file or folder between work and life? [on hold]

    - by sojyq
    I am a programmer from China. And I like to use English words to name my files and folders Whether it is for work or life. For example, suck as Movie, Work, QtProjects, Music and so on.And I keep the habit of initial the first letter for file name or folder name in Windows. But now I work on Ubuntu, and I found that all file name and folder name are lowercase in addition to the default folder such as Music, Movie and so on. And then I realize that in Linux world, most peoloe like to use all lowercase to name their files and folders for two reasons (1. Linux is Case sensitive. 2. It is fast for shell command.). And after work, when I switch from Linux to Windows, I confuse to use all lowercase or the first letter uppercase style to name my files in Windows. I'm caught in a dilemma. I think that all lowercase is more efficiency but the first letter uppercase is more readable. I thought for a long time and want to come up with a good answer to blance the two style name conversion. But I failed. I want to ask you that how you balance the uppercase or lowercase habbit in Windows, Mac, Linux between work and personal life style? Thank you very much! (My current solution is that when I am in Linux, I use all lowercase for files and folders, but when I am in Windows and Mac OS X, I couldn't find a good reason to convince me to use all lowercase ( I think in Windows and Mac OS X, the first letter uppercase style for me is more readable and beautiful).

    Read the article

  • How do programers balance the upper or lower case style to name file or folder between work and life?

    - by sojyq
    I am a programmer from China. And I like to use English words to name my files and folders Whether it is for work or life. For example, suck as Movie, Work, QtProjects, Music and so on.And I keep the habit of initial the first letter for file name or folder name in Windows. But now I work on Ubuntu, and I found that all file name and folder name are lowercase in addition to the default folder such as Music, Movie and so on. And then I realize that in Linux world, most peoloe like to use all lowercase to name their files and folders for two reasons (1. Linux is Case sensitive. 2. It is fast for shell command.). And after work, when I switch from Linux to Windows, I confuse to use all lowercase or the first letter uppercase style to name my files in Windows. I'm caught in a dilemma. I think that all lowercase is more efficiency but the first letter uppercase is more readable. I thought for a long time and want to come up with a good answer to blance the two style name conversion. But I failed. I want to ask you that how you balance the uppercase or lowercase habbit in Windows, Mac, Linux between work and personal life style? Thank you very much! (My current solution is that when I am in Linux, I use all lowercase for files and folders, but when I am in Windows and Mac OS X, I couldn't find a good reason to convince me to use all lowercase ( I think in Windows and Mac OS X, the first letter uppercase style for me is more readable and beautiful).

    Read the article

  • Where did I write that code ?

    - by Tarun Arora
    Every been in that situation when you desperately need to find that code you checked into TFS a few days back but just can’t remember what team project, what branch, what solution or what file you checked it into. Well you are not alone… Only if there was a way to efficiently search for files and text with in TFS. It is possible… You need to get your hands on Agent Ransack… This is a stand a lone tool that does not integrate with TFS but gives you the capability to search through text files effortlessly. Agent Ransack searches through files, text or otherwise, fast and efficiently. When searching the contents of files for code, or other text, Agent Ransack displays the text found so you can quickly browse the results without having to separately open each file! Agent Ransack is free for both Personal and Commercial use and can be Download from here.   Set the Look In directory of the Ransack search tool to your TFS Workspace and type the text you would like to scan for, you can limit the search by narrowing down the filter path or the name of the file. Found text is shown with highlighted keywords so you don't need to waste time opening each file looking for the right information.         The regular expression wizard helps you build regular expressions for complex pattern matching searches         You even have the option of searching by modified, created or last accessed date          Export your results to a file for importing into other apps or for sharing with others          Agent Ransack also provides search support for popular Office formats including Office 2007 and OpenOffice Next time you are looking for that illusive line of code whether it is a method declaration, function call, or algorithm that you checked into TFS, use Agent Ransack for a quick search.

    Read the article

  • How to quickly search through a very large list of strings / records on a database

    - by Giorgio
    I have the following problem: I have a database containing more than 2 million records. Each record has a string field X and I want to display a list of records for which field X contains a certain string. Each record is about 500 bytes in size. To make it more concrete: in the GUI of my application I have a text field where I can enter a string. Above the text field I have a table displaying the (first N, e.g. 100) records that match the string in the text field. When I type or delete one character in the text field, the table content must be updated on the fly. I wonder if there is an efficient way of doing this using appropriate index structures and / or caching. As explained above, I only want to display the first N items that match the query. Therefore, for N small enough, it should not be a big issue loading the matching items from the database. Besides, caching items in main memory can make retrieval faster. I think the main problem is how to find the matching items quickly, given the pattern string. Can I rely on some DBMS facilities, or do I have to build some in-memory index myself? Any ideas? EDIT I have run a first experiment. I have split the records into different text files (at most 200 records per file) and put the files in different directories (I used the content of one data field to determine the directory tree). I end up with about 50000 files in about 40000 directories. I have then run Lucene to index the files. Searching for a string with the Lucene demo program is pretty fast. Splitting and indexing took a few minutes: this is totally acceptable for me because it is a static data set that I want to query. The next step is to integrate Lucene in the main program and use the hits returned by Lucene to load the relevant records into main memory.

    Read the article

  • .net developers and web designers: how to interact?

    - by just_name
    I'm an asp.net developer, and I face some problems when I deal with designers. The designer always complains about the asp.net server controls. They rather just have an html file and create css files along with the required images to go with those. Sometimes if the design phase is done in advance I get html files with related css files, but then we face many problems integrating the design with the aspx files (sever controls an telerik controls ... etc). What I want to ask about is: How to overcome these problems? The designers prefer php- and mvc developers because of the problems with .net server controls. I need to know how to interact with the designers in a correct way. Are there any tools or applications to provide the designers with the rendered (html page) of the .aspx pages? By that I mean the page in runtime rather than the aspx in visual studio. They do use Web Expression but they want the rendered page in html as well.

    Read the article

  • batch: comparing filenames and renaming [migrated]

    - by user2978770
    i'm new to both this platform and batch programming and i'm slowly but steadily driving crazy :-( I'm studying in Germany and just started on a bigger project that mainly consists of analyzing data and finding algorithms in order to maintain a certain function of a system. In order to get started i got a bunch of recorded data that, unfortunately, is not consistent when i comes to naming. Normally all files (all in one folder) should start with SPY.SPYNODE.SIDE and then go on with the specific names for each values or variables. However, the data logger messed it up a couple of times and gives weird names like SP0E1A~1.csv (all files are .csv-files). An that's when i figured in stead of renaming a couple of thousand files manually i could "easily" use a simple batch file to do that job for name. And that's exactly when I started to go crazy :-) So far i came up with the following: FOR /R %%i in (%CD%) DO ( set file1=%%i if not %file1%=="SPY.SPYNODE.SIDE" DO ( set /p "filename" < %file1% rename %file1% %filename% ) ) So what i want it to do is this (in pseudo) look through the whole folder and every file save the filename in variable file1 if file1 partially equals SPY.SPYNODE.SIDE open the file and save the first line (which contains the correct name of the file) in variable filename rename the file with the correct filename But so far it doesn't really work and i don't know why. Could anybody give me a hint or some advice how i should proceed? I really appreciate any kind of help!

    Read the article

  • How to open-source a project whose git repository has copyrighted media in the history?

    - by phyzome
    I want to release an audio fingerprinting software project under a free license, but the repository contains copyrighted audio files. The test cases also currently use these files. How do I release the code to the public with maximum version history but without violating copyright? Details: The code is versioned under git. We will collapse it all back into one branch before release. There are 400 MB of audio data. Some files are free-licensed music from e.g. Jamendo, others are MP3s from our personal collections. No matter what approach we take, we'll always keep an immutable copy of the original repo, so as not to destroy project history. Main question: How to handle the public release? Expunge all history of the files in question from the git repository and release the altered repo. (v64 pointed out a way to do this.) Alternatively, take a snapshot of the current state of the code and don't even bother having a public history of the pre-release code. Side question: How could we have avoided this dilemma in the first place, given that sometimes private code or media is needed for the early stages of a project?

    Read the article

  • VCS for single user using file sync service

    - by StackUnder
    I'm trying to setup a version control for my one man project. My project files are in sync thanks to live mesh (but I could be using dropbox for that matter), between my laptop, my home pc and my office pc. I'm now using Netbeans with local file history. Sometimes it helps to revert to a previous state of one file. But imagine a situation when multiple files have problems. Correct me if I'm wrong but I would have to go to every file and revert to previous "safe" state. I don't like this approach, so I'm considering using a version control between SVN and GIT. I have some previous experience with SVN (TortoiseSVN) and I know that I can create a file:// repo. So, what a want to do is setup a VCS inside my synced folder just to have the ability to "revert" to a previous version if something goes wrong. Since everything's been synced to all computers, I wouldn't ever need to run an update. The file tree organization would be the following: C:...\SyncedFolder\MyProject\ Inside MyProject folder are all the project files plus a directory that has SVN or GIT info of my project (the repo/master). What VCS is best for this situation: SVN or GIT? Does SVN need to store all files from HEAD revision, thus "duplicating" all my project inside my synced folder? Does GIT eliminates this problem? Is this the best approach?

    Read the article

  • std::basic_stringstream<unsigned char> won't compile with MSVC 10

    - by Michael J
    I'm trying to get UTF-8 chars to co-exist with ANSI 8-bit chars. My strategy has been to represent utf-8 chars as unsigned char so that appropriate overloads of functions can be used for the two character types. e.g. namespace MyStuff { typedef uchar utf8_t; typedef std::basic_string<utf8_t> U8string; } void SomeFunc(std::string &s); void SomeFunc(std::wstring &s); void SomeFunc(MyStuff::U8string &s); This all works pretty well until I try to use a stringstream. std::basic_ostringstream<MyStuff::utf8_t> ostr; ostr << 1; MSVC Visual C++ Express V10 won't compile this: c:\program files\microsoft visual studio 10.0\vc\include\xlocmon(213): warning C4273: 'id' : inconsistent dll linkage c:\program files\microsoft visual studio 10.0\vc\include\xlocnum(65) : see previous definition of 'public: static std::locale::id std::numpunct<unsigned char>::id' c:\program files\microsoft visual studio 10.0\vc\include\xlocnum(65) : while compiling class template static data member 'std::locale::id std::numpunct<_Elem>::id' with [ _Elem=Tk::utf8_t ] c:\program files\microsoft visual studio 10.0\vc\include\xlocnum(1149) : see reference to function template instantiation 'const _Facet &std::use_facet<std::numpunct<_Elem>>(const std::locale &)' being compiled with [ _Facet=std::numpunct<Tk::utf8_t>, _Elem=Tk::utf8_t ] c:\program files\microsoft visual studio 10.0\vc\include\xlocnum(1143) : while compiling class template member function 'std::ostreambuf_iterator<_Elem,_Traits> std::num_put<_Elem,_OutIt>:: do_put(_OutIt,std::ios_base &,_Elem,std::_Bool) const' with [ _Elem=Tk::utf8_t, _Traits=std::char_traits<Tk::utf8_t>, _OutIt=std::ostreambuf_iterator<Tk::utf8_t,std::char_traits<Tk::utf8_t>> ] c:\program files\microsoft visual studio 10.0\vc\include\ostream(295) : see reference to class template instantiation 'std::num_put<_Elem,_OutIt>' being compiled with [ _Elem=Tk::utf8_t, _OutIt=std::ostreambuf_iterator<Tk::utf8_t,std::char_traits<Tk::utf8_t>> ] c:\program files\microsoft visual studio 10.0\vc\include\ostream(281) : while compiling class template member function 'std::basic_ostream<_Elem,_Traits> & std::basic_ostream<_Elem,_Traits>::operator <<(int)' with [ _Elem=Tk::utf8_t, _Traits=std::char_traits<Tk::utf8_t> ] c:\program files\microsoft visual studio 10.0\vc\include\sstream(526) : see reference to class template instantiation 'std::basic_ostream<_Elem,_Traits>' being compiled with [ _Elem=Tk::utf8_t, _Traits=std::char_traits<Tk::utf8_t> ] c:\users\michael\dvl\tmp\console\console.cpp(23) : see reference to class template instantiation 'std::basic_ostringstream<_Elem,_Traits,_Alloc>' being compiled with [ _Elem=Tk::utf8_t, _Traits=std::char_traits<Tk::utf8_t>, _Alloc=std::allocator<uchar> ] . c:\program files\microsoft visual studio 10.0\vc\include\xlocmon(213): error C2491: 'std::numpunct<_Elem>::id' : definition of dllimport static data member not allowed with [ _Elem=Tk::utf8_t ] Any ideas? ** Edited 19 June 2012 ** OK, I've gotten closer to understanding this, but not how to solve it. As we all know, static class variables get defined twice: once in the class definition and once outside the class definition which establishes storage space. e.g. // in .h file class CFoo { // ... static int x; }; // in .cpp file int CFoo::x = 42; Now in the VC10 headers we get something like this: template<class _Elem> class numpunct : public locale::facet { // ... _CRTIMP2_PURE static locale::id id; // ... } When the header is included in an application, _CRTIMP2_PURE is defined as __declspec(dllimport), which means that the variable is imported from a dll. Now the header also contains the following template<class _Elem> locale::id numpunct<_Elem>::id; Note the absence of the __declspec(dllimport) qualifier. i.e. The class declaration says that the static linkage of the id variable is in the dll, but for the general case, it gets declared outside the dll. For the known cases, there are specialisations. template locale::id numpunct<char>::id; template locale::id numpunct<wchar_t>::id; These are protected by #ifs so that they are only included when building the DLL. They are excluded otherwise. i.e. the char and wchar_t versions of numpunct ARE inside the dll So we have the class definition saying that id's storage is in the DLL, but that is only true for the char and wchar_t specialisations, meaning that my unsigned char version is doomed. :-( The only way forward that I can think of is to create my own specialisation: basically copying it from the header file and fixing it. This raises many issues. Anybody have a better idea?

    Read the article

  • Tracking download of non-html (like pdf) downloads with jQuery and Google Analytics

    - by developerit
    Hi folks, it’s been quite calm at Developer IT’s this summer since we were all involved in other projects, but we are slowly comming back. In this post, we will present a simple way of tracking files download with Google Analytics with the help of jQuery. We work for a client that offers a lot of pdf files to download on their web site and wanted to know which one are the most popular. They use Google Analytics for a long time now and we did not want to have a second interface in order to present those stats to our client. So usign IIS logs was not a idea to consider. Since Google already offers us a splendid web interface and a powerful API, we deceided to hook up simple javascript code into the jQuery click event to notify Analytics that a pdf has been requested. (function ($) { function trackLink(e) { var url = $(this).attr('href'); //alert(url); // for debug purpose // old page tracker code pageTracker._trackPageview(url); // you can use the new one too _gaq.push(["_trackPageview",url]); //always return true, in order for the browser to continue its job return true; } // When DOM ready $(function () { // hook up the click event $('.pdf-links a').click(trackLink); }); })(jQuery); You can be more presice or even be sure not to miss one click by changing the selector which hooks up the click event. I have been usign this code to track AJAX requests and it works flawlessly.

    Read the article

  • HTML client-side portable file generation - no external resources or server calls

    - by awashburn
    I have the following situation: I have set up a series of Cron jobs on an internal company server to run various PHP scripts designed to check data integrity. Each PHP script queries a company database, formats the returned query data into an HTML file containing one or more <tables>, and then mails the HTML file to several client emails as an attachment. From my experience, most of the PHP scripts generate HTML files with only a few tables, however there are a few PHP scripts the create HTML files with around 30 tables. HTML files have been chosen as the distribution format of these scans because HTML makes it easy to view many tables at once in a browser window. I would like to add the functionality for the clients to download a table in the HTML file as a CSV file. I anticipate clients using this feature when they suspect a data integrity issue based on the table data. It would be ideal for them to be able to take the table in question, export the data out to a CSV file, and then study it further. Because need for exporting the data to CSV format is at the discretion of the client, unpredictable as to what table will be under scrutiny, and intermittently used I do not want to create CSV files for every table. Normally creating a CSV file wouldn't be too difficult, using JavaScript/jQuery to preform DOM traversal and generate the CSV file data into a string utilizing a server call or flash library to facilitate the download process; but I have one limiting constraint: The HTML file needs to be "portable." I would like the clients to be able to take their HTML file and preform analysis of the data outside the company intranet. Also it is likely these HTML files will be archived, so making the export functionality "self contained" in the HTML files is a highly desirable feature for the two previous reasons. The "portable" constraint of CSV file generation from a HTML file means: I cannot make a server call. This means ALL the file generation must be done client-side. I want the single HTML file attached to the email to contain all the resources to generate the CSV file. This means I cannot use jQuery or flash libraries to generate the file. I understand, for obvious security reasons, that writing out files to disk using JavaScript isn't supported by any browser. I don't want to create a file without the user knowledge; I would like to generate the file using JavaScript in memory and then prompt the user the "download" the file from memory. I have looked into generating the CSV file as a URI however, according to my research and testing, this approach has a few problems: URIs for files are not supported by IE (See Here) URIs in FireFox saves the file with a random file name and as a .part file As much as it pains me, I can accept the fact the IE<=v9 won't create a URI for files. I would like to create a semi-cross-browser solution in which Chrome, Firefox, and Safari create a URI to download the CSV file after JavaScript DOM traversal compiles the data. My Example Table: <table> <thead class="resulttitle"> <tr> <th style="text-align:center;" colspan="3"> NameOfTheTable</th> </tr> </thead> <tbody> <tr class="resultheader"> <td>VEN_PK</td> <td>VEN_CompanyName</td> <td>VEN_Order</td> </tr> <tr> <td class='resultfield'>1</td> <td class='resultfield'>Brander Ranch</td> <td class='resultfield'>Beef</td> </tr> <tr> <td class='resultfield'>2</td> <td class='resultfield'>Super Tree Produce</td> <td class='resultfield'>Apples</td> </tr> <tr> <td class='resultfield'>3</td> <td class='resultfield'>John's Distilery</td> <td class='resultfield'>Beer</td> </tr> </tbody> <tfoot> <tr> <td colspan="3" style="text-align:right;"> <button onclick="doSomething(this);">Export to CSV File</button></td> </tr> </tfoot> </table> My Example JavaScript: <script type="text/javascript"> function doSomething(inButton) { /* locate elements */ var table = inButton.parentNode.parentNode.parentNode.parentNode; var name = table.rows[0].cells[0].textContent; var tbody = table.tBodies[0]; /* create CSV String through DOM traversal */ var rows = tbody.rows; var csvStr = ""; for (var i=0; i < rows.length; i++) { for (var j=0; j < rows[i].cells.length; j++) { csvStr += rows[i].cells[j].textContent +","; } csvStr += "\n"; } /* temporary proof DOM traversal was successful */ alert("Table Name:\t" + name + "\nCSV String:\n" + csvStr); /* Create URI Here! * (code I am missing) */ /* Approach 1 : Auto-download * downloads CSV data but: * In FireFox downloads as randomCharacers.part instead of name.csv * In Chrome downloads without prompting the user * In Safari opens the files in browser (textfile) */ //var hrefData = "data:text/csv;charset=US-ASCII," + encodeURIComponent(csvStr); //document.location.href = hrefData; /* Approach 2 : Right-Click Save As... */ var hrefData = "data:text/csv;charset=US-ASCII," + encodeURIComponent(csvStr); var fileLink = document.createElement("a"); fileLink.href = hrefData; fileLink.innerHTML = "download"; parentTD = inButton.parentNode; parentTD.appendChild(fileLink); parentTD.removeChild(inButton); } </script> I am looking for an example solution in which the above example table can be downloaded as a CSV file: using a URI the user is prompted to save the file the default filename is the name of the table. code works as described in modern versions of FireFox, Safari, & Chrome I have added a <script> tag with the DOM traversal function doSomething(). The real help I need is with formatting the URI to what I want within the doSomething() function.

    Read the article

  • Our Look at Opera 10.50 Web Browser

    - by Asian Angel
    Everyone has been talking about the newest version of Opera recently but perhaps you have not looked at it too closely yet. Today we will take a look at 10.50 and let you see what this “new browser” is all about. The New Engines Carakan JavaScript Engine: Runs web applications up to 7 times faster than its predecessor Futhark Vega Graphics Library: Enables super fast and smooth graphics on everything from tab switching to webpage animation Presto 2.5: Provides support for HTML5, CSS2.1 and the latest CSS3 standards A Look at the Features Available If you have installed or used older versions of Opera before then the default look after a clean install will probably seem rather different. The main differences in appearance are mainly located within the “glass border” areas of the browser. The “Speed Dial” setup looks and works just as well as in previous versions. You can set a favorite wallpaper or image as your background and choose the number of “dials” using the “Configure Speed Dial Command”. One of the “standout” differences is the “O Button”. All of the menus have been condensed into this single access point but it only takes a few moments to find what you are looking for. If you have used the style before in earlier versions of Opera some of the items have been moved around. For those who prefer the “Menu Bar” that can be easily restored using the “Show Menu Bar Command”. If desired you can actually “extend” the “Tab Bar” downwards to display thumbnails of your open tabs. Just use your mouse to grab the bottom of the “Tab Bar” and adjust it to suit your personal needs. The only problem with this feature is that it will quickly use up a good sized portion of your available UI and browser window space. The “Password Manager” is ready to access when needed…the background for the button will turn a shiny metallic blue when you open a webpage that you have “Login Information” saved for. One of the new features is a small “Recycle Bin Button” in the upper right corner. Clicking on this will display a list of recently closed tabs letting you have easy access to any tabs that you may have accidentally closed. This is definitely a great feature to have as an easy access button. For those who were used to how the “Zoom Feature” looked before it has a new “look” to it. Instead of the pop-up menu-type listing of “view sizes” present before you now have a slider button that you can use to adjust the zooming level. For our default setup here the “Sidebar Panels” available were: “Bookmarks, Widgets, Unite, Notes, Downloads, History, & Panels”. Additional panels such as “Links, Windows, Search, Info, etc.” are available if you want and/or need them (accessible using the “Panels Plus Sign Button”). The “Opera Link Button” makes it easy for you to synchronize your “Speed Dial, Bookmarks, Personal Bar, Custom Searches, History & Notes”. Note: “Opera Link” requires an account and can be signed up for using the link provided below. Want to share files with your family and friends? “Unite” allows you to do that and more. With “Unite” you can: “Stream Music, Show Photo Galleries, Share Files and/or Folders, & host webpages directly from your browser”. We have a more in-depth look at “Unite” in our article here. Note: Use of “Unite” requires an Opera account. Got a slow internet connection? “Opera Turbo” can help with that by running the web traffic through their “compression servers” to speed up your web browsing. Keep in mind that “Opera Turbo” will not engage if you are accessing a secure website (i.e. your bank’s website) thus preserving your security. Note: “Opera Turbo” can be set up to automatically detect slow internet connections (i.e. crowded Wi-Fi in a cafe). Opera has a built-in “Private Browsing Mode” now for those who prefer anonymous browsing and want to keep the “history records clean” on their computer. To access it go to “Tabs and windows” and select “New private tab” or “New private window” as desired. When you open your new “Private Tab or Window” you will see the following message with details on how Opera will handle browsing information and a large “door hanger symbol”. Notice that the one tab is locked into “Private Browsing Mode” while the others are still working in “Regular Browsing Mode”. Very nice! A miniature version of the “door hanger symbol” will be present on any tab that is locked into “Private Browsing Mode”. If you are using Windows 7 then you will love how things look from your “Taskbar”. Here you can see four very nice looking thumbnails for the tabs that we had open. All that you have to do is click on the desired thumbnail… The “Context Menu” looks just as lovely as the thumbnails and definitely has some terrific functionality built into it. Add Enhanced Aero Capability If you love “Aero” and want more for your new Opera install then we have the perfect theme for you. The theme’s name is Z1-AV69 and once you have downloaded it you will need to place it in the “Skins Subfolder” in Opera’s “Program Files Folder”. Note: For our example we used version 1.10 but version 2.00 is now available (link provided below). Once you have restarted Opera, go to the “O Menu” and select “Appearance”. When the “Appearance Window” opens click on “Z1-Glass Skin” and then click “OK”. All of a sudden you will have more “Aero Goodness” to enjoy. Compare this screenshot with the one at the top of this article…the only part that is not transparent now is the browser window area itself. Want even more “Aero Goodness”? Right click on the “Tab Bar” and set “Tab Bar Placement” to “Left”. Note: You can achieve the same effect by setting the “Tab Bar Placement” to “Right”. With the “Speed Dial” visible you will be able to see your wallpaper with ease. While this is obviously not for everyone it does make for a great visual trick. Portable Versions Perhaps you need this wonderful new version of Opera to go with you wherever you do during the day. Not a problem…just visit the Opera USB website to choose a version that works best for you. You can select from “Zip or Exe” setup files and if needed update an older portable version using a “Zipped Update Files Package”. If you are updating an older version keep in mind that you will need to delete the old “OperaUSB.exe. File” due to changes with the new setup files. During our tests updating older portable versions went well for the most part but we did experience a few “odd UI quirks” here and there…so we recommend setting up a clean install if possible. Conclusion The new 10.50 release is a pleasure to use and is a recommended install for your system. Whether you are considering trying Opera for the first time or have been using it for a bit we think that you will pleased with everything that the 10.50 release has to offer. For those who would like to add User Scripts to Opera be certain to look at our how-to article here. Links Download Opera 10.50 for your location (Windows) Get the latest Snapshot versions for Linux & Mac Sign up for an Opera Link account View In-Depth detail on Opera 10.50’s features Download the Z1-AV69 Aero Theme Download Portable Opera 10.50 Similar Articles Productive Geek Tips Set the Speed Dial as the Opera Startup PageSet Up User Scripts in Opera BrowserScan Files for Viruses Before You Download With Dr.WebTurn Your Computer into a File, Music, and Web Server with Opera UniteSet the Default Browser on Ubuntu From the Command Line TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Make your Joomla & Drupal Sites Mobile with OSMOBI Integrate Twitter and Delicious and Make Life Easier Design Your Web Pages Using the Golden Ratio Worldwide Growth of the Internet How to Find Your Mac Address Use My TextTools to Edit and Organize Text

    Read the article

  • Migrating SQL Server Databases – The DBA’s Checklist (Part 1)

    - by Sadequl Hussain
    It is a fact of life: SQL Server databases change homes. They move from one instance to another, from one version to the next, from old servers to new ones.  They move around as an organisation’s data grows, applications are enhanced or new versions of the database software are released. If not anything else, servers become old and unreliable and databases eventually need to find a new home. Consider the following scenarios: 1.     A new  database application is rolled out in a production server from the development or test environment 2.     A copy of the production database needs to be installed in a test server for troubleshooting purposes 3.     A copy of the development database is regularly refreshed in a test server during the system development life cycle 4.     A SQL Server is upgraded to a newer version. This can be an in-place upgrade or a side-by-side migration 5.     One or more databases need to be moved between different instances as part of a consolidation strategy. The instances can be running the same or different version of SQL Server 6.     A database has to be restored from a backup file provided by a third party application vendor 7.     A backup of the database is restored in the same or different instance for disaster recovery 8.     A database needs to be migrated within the same instance: a.     Files are moved from direct attached storage to storage area network b.    The same database is copied under a different name for another application Migrating SQL Server database applications is a complex topic in itself. There are a number of components that can be involved: jobs, DTS or SSIS packages, logins or linked servers are only few pieces of the puzzle. However, in this article we will focus only on the central part of migration: the installation of the database itself. Unless it is an in-place upgrade, typically the database is taken from a source server and installed in a destination instance.  Most of the time, a full backup file is used for the rollout. The backup file is either provided to the DBA or the DBA takes the backup and restores it in the target server. Sometimes the database is detached from the source and the files are copied to and attached in the destination. Regardless of the method of copying, moving, refreshing, restoring or upgrading the physical database, there are a number of steps the DBA should follow before and after it has been installed in the destination. It is these post database installation steps we are going to discuss below. Some of these steps apply in almost every scenario described above while some will depend on the type of objects contained within the database.  Also, the principles hold regardless of the number of databases involved. Step 1:  Make a copy of data and log files when attaching and detaching When detaching and attaching databases, ensure you have made copies of the data and log files if the destination is running a newer version of SQL Server. This is because once attached to a newer version, the database cannot be detached and attached back to an older version. Trying to do so will give you a message like the following: Server: Msg 602, Level 21, State 50, Line 1 Could not find row in sysindexes for database ID 6, object ID 1, index ID 1. Run DBCC CHECKTABLE on sysindexes. Connection Broken If you try to backup the attached database and restore it in the source, it will still fail. Similarly, if you are restoring the database in a newer version, it cannot be backed up or detached and put back in an older version of SQL. Unlike detach and attach method though, you do not lose the backup file or the original database here. When detaching and attaching a database, it is important you keep all the log files available along with the data files. It is possible to attach a database without a log file and SQL Server can be instructed to create a new log file, however this does not work if the database was detached when the primary file group was read-only. You will need all the log files in such cases. Step 2: Change database compatibility level Once the database has been restored or attached to a newer version of SQL Server, change the database compatibility level to reflect the newer version unless there is a compelling reason not to do so. When attaching or restoring from a previous version of SQL, the database retains the older version’s compatibility level.  The only time you would want to keep a database with an older compatibility level is when the code within your database is no longer supported by SQL Server. For example, outer joins with *= or the =* operators were still possible in SQL 2000 (with a warning message), but not in SQL 2005 anymore. If your stored procedures or triggers are using this form of join, you would want to keep the database with an older compatibility level.  For a list of compatibility issues between older and newer versions of SQL Server databases, refer to the Books Online under the sp_dbcmptlevel topic. Application developers and architects can help you in deciding whether you should change the compatibility level or not. You can always change the compatibility mode from the newest to an older version if necessary. To change the compatibility level, you can either use the database’s property from the SQL Server Management Studio or use the sp_dbcmptlevel stored procedure.   Bear in mind that you cannot run the built-in reports for databases from SQL Server Management Studio if you keep the database with an older compatibility level. The following figure shows the error message I received when trying to run the “Disk Usage by Top Tables” report against a database. This database was hosted in a SQL Server 2005 system and still had a compatibility mode 80 (SQL 2000).     Continues…

    Read the article

  • LightDM will not start after stopping it

    - by Sweeters
    I am running Ubuntu 11.10 "Oneiric Ocelot", and in trying to install the nvidia CUDA developer drivers I switched to a virtual terminal (Ctrl-Alt-F5) and stopped lightdm (installation required that no X server instance be running) through sudo service lightdm stop. Re-starting lightdm with sudo service lightdm start did not work: A couple of * Starting [...] lines where displayed, but the process hanged. (I do not remember at which point, but I think it was * Starting System V runlevel compatibility. I manually rebooted my laptop, and ever since booting seems to hang, usually around the * Starting anac(h)ronistic cron [OK] log line (not consistently at that point, though). From that point on, I seem to be able to interact with my system only through a tty session (Ctrl-Alt-F1). I've tried purging and reinstalling both lightdm and gdm, as well as selecting both as the default display managers (through sudo dpkg-reconfigure [lightdm / gdm] or by manually editing /etc/X11/default-display-manager) through both apt-get and aptitude (that shouldn't make a difference anyway) after updating the packages, but the problem persists. Some of the responses I'm getting are the following: After running sudo dpkg-reconfigure lightdm (but not ... gdm) I get the following message: dpkg-maintscript-helper:warning: environment variable DPKG_MATINSCRIPT_NAME missing dpkg-maintscript-helper:warning: environment variable DPKG_MATINSCRIPT_PACKAGE missing After trying sudo service lightdm start or sudo start lightdm I get to see the boot loading screen again but nothing changes. If I go back to the tty shell I see lightdm start/running, process <num> but ps -e | grep lightdm gives no output. After trying sudo service gdm start or sudo starg gdm I get the gdm start/running, process <num> message, and gdm-binary is supposedly an active process, but all that happens is that the screen blinks a couple of times and nothing else. Other candidate solutions that I'd found on the web included running startx but when I try that I get an error output [...] Fatal server error: no screens found [...]. Moreover, I made sure that lightdm-gtk-greeter is installed but that did not help either. Please excuse my not including complete outputs/logs; I am writing this post from another computer and it's hard to manually copy the complete logs. Also, I've seen several posts that had to do with similar problems, but either there was no fix, or the one suggested did not work for me. In closing: Please help! I very much hope to avoid re-installing Ubuntu from scratch! :) Alex @mosi I did not manage to fix the NVIDIA kernel driver as per your instructions. I should perhaps mention that I'm on a Dell XPS15 laptop with an NVIDIA Optimus graphics card, and that I have bumblebee installed (which installs nvidia drivers during its installation, I believe). Issuing the mentioned commands I get the following: ~$uname -r 3.0.0-12-generic ~$lsmod | grep -i nvidia nvidia 11713772 0 ~$dmesg | grep -i nvidia [ 8.980041] nvidia: module license 'NVIDIA' taints kernel. [ 9.354860] nvidia 0000:01:00.0: power state changed by ACPI to D0 [ 9.354864] nvidia 0000:01:00.0: power state changed by ACPI to D0 [ 9.354868] nvidia 0000:01:00.0: enabling device (0006 -> 0007) [ 9.354873] nvidia 0000:01:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16 [ 9.354879] nvidia 0000:01:00.0: setting latency timer to 64 [ 9.355052] NVRM: loading NVIDIA UNIX x86_64 Kernel Module 280.13 Wed Jul 27 16:53:56 PDT 2011 Also, running aptitude search nvidia gives me the following: p nvidia-173 - NVIDIA binary Xorg driver, kernel module a p nvidia-173-dev - NVIDIA binary Xorg driver development file p nvidia-173-updates - NVIDIA binary Xorg driver, kernel module a p nvidia-173-updates-dev - NVIDIA binary Xorg driver development file p nvidia-96 - NVIDIA binary Xorg driver, kernel module a p nvidia-96-dev - NVIDIA binary Xorg driver development file p nvidia-96-updates - NVIDIA binary Xorg driver, kernel module a p nvidia-96-updates-dev - NVIDIA binary Xorg driver development file p nvidia-cg-toolkit - Cg Toolkit - GPU Shader Authoring Language p nvidia-common - Find obsolete NVIDIA drivers i nvidia-current - NVIDIA binary Xorg driver, kernel module a p nvidia-current-dev - NVIDIA binary Xorg driver development file c nvidia-current-updates - NVIDIA binary Xorg driver, kernel module a p nvidia-current-updates-dev - NVIDIA binary Xorg driver development file i nvidia-settings - Tool of configuring the NVIDIA graphics dr p nvidia-settings-updates - Tool of configuring the NVIDIA graphics dr v nvidia-va-driver - v nvidia-va-driver - I've tried manually installing (sudo aptitude install <package>) packages nvidia-common and nvidia-settings-updates but to no avail. For example, sudo aptitude install nvidia-settings-updates returns the following log: Reading package lists... Building dependency tree... Reading state information... Reading extended state information... Initializing package states... Writing extended state information... No packages will be installed, upgraded, or removed. 0 packages upgraded, 0 newly installed, 0 to remove and 83 not upgraded. Need to get 0 B of archives. After unpacking 0 B will be used. Writing extended state information... Reading package lists... Building dependency tree... Reading state information... Reading extended state information... Initializing package states... Writing extended state information... The same happens with the Linux headers (i.e. I cannot seem to be able to install linux-headers-3.0.0-12-generic). The output of aptitude search linux-headers is as follows: v linux-headers - v linux-headers - v linux-headers-2.6 - i linux-headers-2.6.38-11 - Header files related to Linux kernel versi i linux-headers-2.6.38-11-generic - Linux kernel headers for version 2.6.38 on i A linux-headers-2.6.38-8 - Header files related to Linux kernel versi i A linux-headers-2.6.38-8-generic - Linux kernel headers for version 2.6.38 on v linux-headers-3 - v linux-headers-3.0 - v linux-headers-3.0 - i A linux-headers-3.0.0-12 - Header files related to Linux kernel versi p linux-headers-3.0.0-12-generic - Linux kernel headers for version 3.0.0 on p linux-headers-3.0.0-12-generic- - Linux kernel headers for version 3.0.0 on p linux-headers-3.0.0-12-server - Linux kernel headers for version 3.0.0 on p linux-headers-3.0.0-12-virtual - Linux kernel headers for version 3.0.0 on p linux-headers-generic - Generic Linux kernel headers p linux-headers-generic-pae - Generic Linux kernel headers v linux-headers-lbm - v linux-headers-lbm - v linux-headers-lbm-2.6 - v linux-headers-lbm-2.6 - p linux-headers-lbm-3.0.0-12-gene - Header files related to linux-backports-mo p linux-headers-lbm-3.0.0-12-gene - Header files related to linux-backports-mo p linux-headers-lbm-3.0.0-12-serv - Header files related to linux-backports-mo p linux-headers-server - Linux kernel headers on Server Equipment. p linux-headers-virtual - Linux kernel headers for virtual machines @heartsmagic I did try purging and reinstalling any nvidia driver packages, but it did not seem to make a difference, My xorg.conf file contains the following: # nvidia-xconfig: X configuration file generated by nvidia-xconfig # nvidia-xconfig: version 280.13 ([email protected]) Wed Jul 27 17:15:58 PDT 2011 Section "ServerLayout" Identifier "Layout0" Screen 0 "Screen0" 0 0 InputDevice "Keyboard0" "CoreKeyboard" InputDevice "Mouse0" "CorePointer" EndSection Section "Files" EndSection Section "InputDevice" # generated from default Identifier "Mouse0" Driver "mouse" Option "Protocol" "auto" Option "Device" "/dev/psaux" Option "Emulate3Buttons" "no" Option "ZAxisMapping" "4 5" EndSection Section "InputDevice" # generated from default Identifier "Keyboard0" Driver "kbd" EndSection Section "Monitor" Identifier "Monitor0" VendorName "Unknown" ModelName "Unknown" HorizSync 28.0 - 33.0 VertRefresh 43.0 - 72.0 Option "DPMS" EndSection Section "Device" Identifier "Device0" Driver "nvidia" VendorName "NVIDIA Corporation" EndSection Section "Screen" Identifier "Screen0" Device "Device0" Monitor "Monitor0" DefaultDepth 24 SubSection "Display" Depth 24 EndSubSection EndSection

    Read the article

  • Azure, don't give me multiple VMs, give me one elastic VM

    - by FransBouma
    Yesterday, Microsoft revealed new major features for Windows Azure (see ScottGu's post). It all looks shiny and great, but after reading most of the material describing the new features, I still find the overall idea behind all of it flawed: why should I care on how much VMs my web app runs? Isn't that a problem to solve for the Windows Azure engineers / software? And what if I need the file system, why can't I simply get a virtual filesystem ? To illustrate my point, let's use a real example: a product website with a customer system/database and next to it a support site with accompanying database. Both are written in .NET, using ASP.NET and use a SQL Server database each. The product website offers files to download by customers, very simple. You have a couple of options to host these websites: Buy a server, place it in a rack at an ISP and run the sites on that server Use 'shared hosting' with an ISP, which means your sites' appdomains are running on the same machine, as well as the files stored, and the databases are hosted in the same server as the other shared databases. Hire a VM, install your OS of choice at an ISP, and host the sites on that VM, basically the same as the first option, except you don't have a physical server At some cloud-vendor, either host the sites 'shared' or in a VM. See above. With all of those options, scalability is a problem, even the cloud-based ones, though not due to the same reasons: The physical server solution has the obvious problem that if you need more power, you need to buy a bigger server or more servers which requires you to add replication and other overhead Shared hosting solutions are almost always capped on memory usage / traffic and database size: if your sites get too big, you have to move out of the shared hosting environment and start over with one of the other solutions The VM solution, be it a VM at an ISP or 'in the cloud' at e.g. Windows Azure or Amazon, in theory allows scaling out by simply instantiating more VMs, however that too introduces the same overhead problems as with the physical servers: suddenly more than 1 instance runs your sites. If a cloud vendor offers its services in the form of VMs, you won't gain much over having a VM at some ISP: the main problems you have to work around are still there: when you spin up more than one VM, your application must be completely stateless at any moment, including the DB sub system, because what's in memory in instance 1 might not be in memory in instance 2. This might sounds trivial but it's not. A lot of the websites out there started rather small: they were perfectly runnable on a single machine with normal memory and CPU power. After all, you don't need a big machine to run a website with even thousands of users a day. Moving these sites to a multi-VM environment will cause a problem: all the in-memory state they use, all the multi-page transitions they use while keeping state across the transition, they can't do that anymore like they did that on a single machine: state is something of the past, you have to store every byte of state in either a DB or in a viewstate or in a cookie somewhere so with the next request, all state information is available through the request, as nothing is kept in-memory. Our example uses a bunch of files in a file system. Using multiple VMs will require that these files move to a cloud storage system which is mounted in each VM so we don't have to store the files on each VM. This might require different file paths, but this change should be minor. What's perhaps less minor is the maintenance procedure in place on the new type of cloud storage used: instead of ftp-ing into a VM, you might have to update the files using different ways / tools. All in all this makes moving an existing website which was written for an environment that's based around a VM (namely .NET with its CLR) overly cumbersome and problematic: it forces you to refactor your website system to be able to be used 'in the cloud', which is caused by the limited way how e.g. Windows Azure offers its cloud services: in blocks of VMs. Offer a scalable, flexible VM which extends with my needs Instead, cloud vendors should offer simply one VM to me. On that VM I run the websites, store my DB and my files. As it's a virtual machine, how this machine is actually ran on physical hardware (e.g. partitioned), I don't care, as that's the problem for the cloud vendor to solve. If I need more resources, e.g. I have more traffic to my server, way more visitors per day, the VM stretches, like I bought a bigger box. This frees me from the problem which comes with multiple VMs: I don't have any refactoring to do at all: I can simply build my website as if it runs on my local hardware server, upload it to the VM offered by the cloud vendor, install it on the VM and I'm done. "But that might require changes to windows!" Yes, but Microsoft is Windows. Windows Azure is their service, they can make whatever change to what they offer to make it look like it's windows. Yet, they're stuck, like Amazon, in thinking in VMs, which forces developers to 'think ahead' and gamble whether they would need to migrate to a cloud with multiple VMs in the future or not. Which comes down to: gamble whether they should invest time in code / architecture which they might never need. (YAGNI anyone?) So the VM we're talking about, is that a low-level VM which runs a guest OS, or is that VM a different kind of VM? The flexible VM: .NET's CLR ? My example websites are ASP.NET based, which means they run inside a .NET appdomain, on the .NET CLR, which is a VM. The only physical OS resource the sites need is the file system, however this too is accessed through .NET. In short: all the websites see is what .NET allows the websites to see, the world as the websites know it is what .NET shows them and lets them access. How the .NET appdomain is run physically, that's the concern of .NET, not mine. This begs the question why Windows Azure doesn't offer virtual appdomains? Or better: .NET environments which look like one machine but could be physically multiple machines. In such an environment, no change has to be made to the websites to migrate them from a local machine or own server to the cloud to get proper scaling: the .NET VM will simply scale with the need: more memory needed, more CPU power needed, it stretches. What it offers to the application running inside the appdomain is simply increasing, but not fragmented: all resources are available to the application: this means that the problem of how to scale is back to where it should be: with the cloud vendor. "Yeah, great, but what about the databases?" The .NET application communicates with the database server through a .NET ADO.NET provider. Where the database is located is not a problem of the appdomain: the ADO.NET provider has to solve that. I.o.w.: we can host the databases in an environment which offers itself as a single resource and is accessible through one connection string without replication overhead on the outside, and use that environment inside the .NET VM as if it was a single DB. But what about memory replication and other problems? This environment isn't simple, at least not for the cloud vendor. But it is simple for the customer who wants to run his sites in that cloud: no work needed. No refactoring needed of existing code. Upload it, run it. Perhaps I'm dreaming and what I described above isn't possible. Yet, I think if cloud vendors don't move into that direction, what they're offering isn't interesting: it doesn't solve a problem at all, it simply offers a way to instantiate more VMs with the guest OS of choice at the cost of me needing to refactor my website code so it can run in the straight jacket form factor dictated by the cloud vendor. Let's not kid ourselves here: most of us developers will never build a website which needs a truck load of VMs to run it: almost all websites created by developers can run on just a few VMs at most. Yet, the most expensive change is right at the start: moving from one to two VMs. As soon as you have refactored your website code to run across multiple VMs, adding another one is just as easy as clicking a mouse button. But that first step, that's the problem here and as it's right there at the beginning of scaling the website, it's particularly strange that cloud vendors refuse to solve that problem and leave it to the developers to solve that. Which makes migrating 'to the cloud' particularly expensive.

    Read the article

< Previous Page | 355 356 357 358 359 360 361 362 363 364 365 366  | Next Page >