"…mais ce serait peut-être l'une des plus grandes opportunités manquées de notre époque si le logiciel libre ne libérait rien d'autre que du code…"

Archive for the ‘Développement logiciel’ Category

Python packaging : Hitchhiker guide, toydist, envbuilder

Posted by patrick sur avril 22, 2010

Toujours beaucoup de mouvement en ce qui concerne la distribution de modules python.

  • http://cournape.wordpress.com/2010/04/22/first-public-release-of-toydist/ (‘The goals of toydist are simplicity and extensibility. There should be only one way to package simple packages (ideally, relying only on the toysetup.info file), while being flexible enough to handle complex softwares. The ultimate goal of toydist is to replace the hideous distutils extensions to build NumPy and SciPy. ‘)
  • http://pypi.python.org/pypi/envbuilder/0.3.0 (‘ A package for automatic generation of virtualenvs Envbuilder is a system for automatically building virtualenvs in Python. To do this, it uses a .env config file to define parcels, which are individual pieces of software to be checked out and installed into the virtualenv. It is mainly tested under Linux, but it should work under any platform that supports unix-y commands (including cygwin). In fact, you might even be able to make one config file work on both Windows and *nix if you’re careful.’)
Publicités

Posted in 2010, Développement logiciel, distribute, Distribution de logiciel, Doc_sphinx, Génie logiciel, package_management, packaging, toydist | Leave a Comment »

Le service de construction de paquetages d’openSUSE : openSUSE build service (OBS)

Posted by patrick sur avril 7, 2010

  • http://en.wikipedia.org/wiki/OpenSUSE_Build_Service (« …The openSUSE Build Service is an open and complete distribution development platform designed to encourage developers to compile packages for multiple Linux distributions including openSUSE, Red Hat, Mandriva, Ubuntu, Fedora and Debian. It typically simplifies the packaging process, so developers can more easily package a single program for many distributions, and many openSUSE releases, making more packages available to users regardless of what distribution version they use. The build service software is published under the GPL. In an acknowledgement of its usefulness to the wider Linux community, the Linux Foundation has announced that the project will be added to the Linux Developer Network (LDN) »)
  • http://fr.opensuse.org/Build_Service ( » … OpenSUSE Build Service (OBS) est une plateforme complète de développement de distribution fournissant l’infrastructure nécessaire pour le développement des futures distributions basées sur openSUSE. Il comporte également les services qui permettent la compilation et la création de paquets pour les autres distributions Linux, comme Fedora, Debian, Ubuntu, et bien d’autres. Les utilisateurs d’openSUSE peuvent facilement passer en revue les différents paquets via l’interface web http://software.opensuse.org/ et télécharger les derniers paquets. Les interfaces ouvertes permettent aux services externes (par ex: SourceForge) et aux pages web d’interagir avec le Build Service et d’utiliser ses ressources…..)

Posted in 2010, command line interface, Développement logiciel, Distribution de logiciel, logiciel libre, openSUSE build service, packaging, python | Tagué: , , , , , , | Leave a Comment »

Richard Stallman à Grenoble le 14 janvier 2010: « Le logiciel libre dans l’éthique et dans la pratique »

Posted by patrick sur décembre 11, 2009

Sources

Grenoble, France – Amphithéatre de l’École de Management de Grenoble, 12, rue Pierre Sémard –

Richard Stallman a parlera des buts et de la philosophie du mouvement du logiciel libre ainsi que de l’histoire du système d’exploitation GNU qui, en combinaison avec le noyau Linux, est aujourd’hui utilisé par plus de 10 millions d’utilisateurs dans le monde.

Entrée libre

A voir

la fin de la conférence


Posted in Développement logiciel, FSF, GNU project, GNU/Linux, Grenoble, logiciel libre, Richard Stallman | Tagué: | Leave a Comment »

Logiciel libre: nouvelle campagne d’adhésion de l’APRIL: objectif 5000 adhérents pour la fin de l’année 2008

Posted by patrick sur décembre 11, 2008

banniere_campagne-adhesion-objectif-5000-adherents
  • Presque un mois après le lancement c’est plus de 880 personnes qui ont répondu présente à notre appel ainsi que plus de 50 entreprises  et près de 25 associations.  Nous approchons donc la barrre des 1 000 nouveaux adhérents. Symboliquement ce serait bien de la dépasser d’ici le 12 décembre.  Ce jour-là nous organisons en effet (ou participons à) quatre soirées (voir http://www.april.org/fr/lapril-fete-ses-12-ans) et nous organisons  une conférence de presse de bilan 2008. À cette occasion sera d’ailleurs  annoncée l’adhésion à l’April d’un nouveau type de personne morale. Il est important de continuer à bien relayer la campagne pour que le rythme  se maintienne.

Parmi les récents soutiens notons Ubuntu-fr :

Adhérer à l'APRIL pour lutter contre les brevets abusifs:
  • http://www.numerama.com/magazine/10718-L-Office-europeen-des-brevets-en-greve-pour-denoncer-les-abus.htm (‘« Chaque année, le nombre de brevets déposés en Europe augmente. Alors que les gouvernements y voient le signe d’une recherche en bonne santé, des examinateurs de l’Office européen des brevets manifestent et dénoncent un emballement néfaste à la qualité de l’innovation, encouragé pour des raisons purement financières et politiques…Les attaques contre les abus de propriété intellectuelle se multiplient ces dernières années sous l’influence des lobbys du logiciel libre, des groupes de défense des intérêts publics, des internautes qui réclament la possibilité de partager librement les oeuvres, des organisations qui militent contre la brevetabilité du vivant ou en faveur d’un assouplissement des règles de protection des molécules des médicaments à destination des pays les plus défavorisés. Après plus d’un siècle de laisser-faire où la propriété intellectuelle s’est toujours renforcée à coups d’accords internationaux (ce qu’ils essayent encore de faire), le balancier ne demande qu’à partir dans l’autre sens...Vendredi dernier, des examinateurs de brevets et d’autres employés de l’Office Européen des Brevets (OEB) ont ainsi manifesté dans les rues de Bruxelles devant la Commission Européenne, non pas pour demander une réévaluation de leur statut ou de leur salaire… mais simplement pour demander une réforme du système des brevets qui arrêterait enfin de freiner l’innovation au lieu de l’encouragerLe nombre de demandes de brevets augmente chaque année. Alors qu’il était de 60.000 demandes en 1990, 209.000 brevets ont été déposées en 2006. Or plus le nombre de brevets augmente, plus le risque juridique des entreprises qui innovent grossit. Statistiquement, les chances de violer un brevet sont multipliées par le nombre de titres octroyés en circulation. Par crainte de représailles, et par manque de solidité financière pour acquérir les licences, les petites et moyennes entreprises gèlent leurs travaux de recherche et développement lorsqu’elles s’aperçoivent qu’elles exploitent de près ou de loin un procédé breveté, ou qu’elles le craignent. Quand bien même la validité du brevet serait à coup sûr annulée en justice en cas de procès, les entreprises préfèrent abandonner leurs recherches que de risquer une procédure judiciaire très longue, très coûteuse, qui les mènerait à la faillite avant son terme.‘)

A voir

carte-membre-tristan-nitot

  • vlc-logo1« VideoLAN encourage ses utilisateurs français à adhérer à l’association amie April. L’April, par le passé, a soutenu VideoLAN dès le début de son aventure dans le logiciel libre. L’action de l’April, lors de son engagement contre des projets de lois bloquant le logiciel libre ou pour la défense de la GPL, est soutenue par l’équipe de VideoLAN. »

Faites comme Tristan Nitot et les autres membres de l’association :

A lire et relire 🙂

  • block-aprilhttp://www.april.org/ (‘Pionnière du logiciel libre en France, l’April, constituée de 3520 adhérents (3252 individus, 268 entreprises, associations et collectivités), est depuis 1996 un acteur majeur de la démocratisation et de la diffusion du logiciel libre et des standards ouverts auprès du grand public, des professionnels et des institutions dans l’espace francophone’)
  • 200px-april_logo_for-big-prints_rgbsvghttp://fr.wikipedia.org/wiki/April_(association) (‘L’April (Association pour la Promotion et la Recherche en Informatique Libre) est une association qui a pour but la promotion et la défense du logiciel libre dans l’espace francophone. À ce titre, elle entretient depuis le début des rapports étroits avec la Free Software Foundation, et traduit depuis longtemps la section philosophie[1] du projet GNU.’)
  • http://www.april.org/fr/brevets-sur-les-logiciels (‘Les brevets sur les logiciels constituent une menace pesante sur l’ensemble de l’industrie du logiciel, qu’il soit libre ou non. ‘)
  • ssp-468-96 http://www.ffii.org/ The Foundation for a Free Information Infrastructure (FFII) is a non-profit organisation dedicated to establishing a free market in information technology, by the removal of barriers to competition. The FFII was largely responsible for the rejection of the EU software patent directive in July 2005, working closely with the European Parliament and many partners from industry and civil society. CNET awarded the FFII the Outstanding contribution to software development award for this work, which was the result of years of research, policy, and action. Today we continue to defend your right to a free and competitive software market by working towards sane patent systems and open standards.

Posted in 2008, april, Développement logiciel, GPL, licence libre, logiciel libre, migration vers le libre, Richard Stallman | Tagué: , , , , , , , , | Leave a Comment »

Code source, gestionnaire de versions/code: mercurial, bazaar, git

Posted by patrick sur juillet 7, 2008

Quelques informations concernant la gestion des programmes source sous GNU/Debian Ubuntu.

Comment obtenir les sources d’un programme sous Debian/Ubuntu ?
=========================================

Quand on installe une distribution Debian/Ubuntu nous avons un ensemble de logiciels sous forme de fichiers (ou paquets) binaires, la liste de ces « paquets » étant donné dans le fichier /etc/apt/sources.list. Si l’on veut consulter le code source correspondant à ces  programmes, il faudra:

  • modifier le fichier /etc/apt/sources.list (sudo gtkedit /etc/apt/sources.list) en rajoutant pour chaque ligne commençant par « deb http://xxxx… » une ligne « deb-src http://xxx… ».
  • lancer commande « sudo apt-get update » pour mettre à jour la liste des paquets.

Si l’on veut voir à quoi ressemble les sources de l’interpréteur python on se crée un répertoire ~/src/python par exemple et un simple « apt-get source python2.5 » suffira pour télécharger les sources. A cette occasion, on aura le message suivant:

Lecture des listes de paquets... Fait
Construction de l'arbre des dépendances
Lecture des informations d'état... Fait
NOTE : l'empaquetage de 'python2.5' est maintenu dans le système de contrôle de version 'Bzr' à:
http://bazaar.launchpad.net/~doko/python/pkg2.5
Veuillez utiliser:
bzr get http://bazaar.launchpad.net/~doko/python/pkg2.5
pour télécharger les dernières mises à jours (probablement non publiées) de ce module.

On apprend donc que ce paquet Ubuntu est géré avec un logiciel de gestion de version distribué appelé ‘bazaar’ (petit nom :’ bzr’) ce logiciel étant écrit en python (faire un apt-get source bzr pour voir le code python).

Pourquoi vouloir obtenir le code source  d’un programme ?
==================================

  • les logiciels libres/open source étant des logiciels de très bonne qualité, il est très intéressant de voir comment tel programme a été implémenté
  • cela permet de contrôler le contenu d’un programme (absence de spywares par exemple) et/ou de faire une revue de code (http://en.wikipedia.org/wiki/Code_review)
  • si on est très motivé, cela permet de participer au développement d’un logiciel ou si l’on n’est pas développeur de participer à sa documentation.

Les gestionnaires de versions
================

La participation à un projet open source implique l’utilisation d’un gestionnaire de versions. Depuis 2003 environ, CVS  est progressivement remplacé par subversion. Et depuis quelques moi, subversion est remplacé par des systèmes de gestion distribué tels que Mercurial (ou hg, écrit lui aussi en python), git (écrit par Linus Torwals), et bazaar.

Ainsi le langage python actuellement géré avec subversion pourrait passer sous bazaar ou mercurial:  http://www.python.org/dev/bazaar/ (« Python’s source code is maintained under the Subversion revision control system. We are experimenting with distributed revision control systems (dvcs) because of their greatly improved workflow, accessibility and merging facilities over Subversion. While there are several serious dvcs contenders in the open source world, this page describes the experimental Bazaar mirrors of the Python Subversion tree that we are making available to developers« )

A voir:

  • http://en.wikipedia.org/wiki/Bazaar_(software) (« Bazaar (formerly Bazaar-NG) is a distributed revision control system sponsored by Canonical Ltd., designed to make it easier for anyone to contribute to free and open source software projectsBazaar is written in the Python programming language, with packages for major LinuxMac OS X and Windows. Bazaar is free software and part of the distributions, GNU projectBazaar has support for working with some other revision control systems.[3] This allows users to branch from another system (such as Subversion), make local changes and commit them into a Bazaar branch, and then later merge them back into the other system. Bazaar has basic support for Subversion with the bzr-svn plugin.[4] There is also beginnings of support for both Mercurial[5] and Git.[6] Currently these are not feature complete, but are complete enough to show a graphical history. »)
  • http://bazaar-vcs.org/WhoUsesBzr
  • http://wiki.list.org/display/DEV/MailmanOnLaunchpad (« The Mailman source code was originally maintained using CVS, and only a few people had write access to the code. Later, development was moved to SourceForge and then the CVS repository was converted to Subversion. This proved to be a successful transition, as Subversion provided many benefits over CVS.Now however, it’s become clear that even Subversion has its limitations, and better options exist. Specifically, we are now using the distributed (or decentralized) revision control system (dvcs) called Bazaar. Bazaar has many beneficial features, both for the core developers and for casual, third party developers. »)

Posted in 2008, Développement logiciel, Génie logiciel, Gestion de version, GNU/Linux, logiciel libre, python, Revue de code, ubuntu | Leave a Comment »

Nouvelle version majeure de GCC : GCC 4.3.0

Posted by patrick sur mars 11, 2008

GCC est utilisé pour le développement de la plupart des logiciels libres. Le noyau Linux dépend notamment étroitement des fonctionnalités de GCC.

GCC 4.3.0 has been released. GCC 4.3.0 is a major release, containing substantial new functionality not available in GCC 4.2.x or previous GCC releases. See: http://gcc.gnu.org/gcc-4.3/changes.html for more information about changes in GCC 4.3.0.

There is one important caveat. It was discovered after the final release
has been made that some OS kernels on i?86 and x86_64 architectures
violate the processor specific ABI with regards to the DF flag, if a process
is interrupted with a signal while doing overlapping memmove or running some other code with DF flag set, the signal handler might be started with DF flag set on entry to the signal handler. GCC 4.3.0 no longer emits cld instructions unnecessarily, so GCC 4.3.0 compiled async signal handlers or functions the signal handlers call that rely on DF flag being cleared might misbehave. This will be hopefully fixed in the kernels soon and future GCC releases might provide an optional workaround for this bug.

Fixes for some systems:
Linux http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=e40cd10ccff3d9fbffd57b93780bee4b7b9bff51
FreeBSD http://www.freebsd.org/cgi/query-pr.cgi?pr=121422
Hurd http://sources.redhat.com/ml/libc-alpha/2008-03/msg00020.html

http://gcc.gnu.org/gcc-4.3/changes.html (« GCC requires the GMP and MPFR libraries for building all the various front-end languages it supports. See the prerequisites page for version requirementsThe GCC middle-end has been integrated with the MPFR library. This allows GCC to evaluate and replace at compile-time calls to built-in math functions having constant arguments with their mathematically equivalent results. In making use of MPFR, GCC can generate correct results regardless of the math library implementation or floating point precision of the host platform. This also allows GCC to generate identical results regardless of whether one compiles in native or cross-compile configurations to a particular target….C++: Experimental support for the upcoming ISO C++ standard, C++0x. -Wc++0x-compat has been added and is now enabled by default for -Wall. It produces warnings for constructs whose meaning differs between ISO C++ 1998 and C++0x… An experimental parallel mode has been added. This is a parallel implementation of many C++ Standard library algorithms, like std::accumulate, std::for_each, std::transform, or std::sort, to give but four examples…Java: gcj now uses the Eclipse Java compiler for its Java parsing needs. This enables the use of all 1.5 language features, and fixes most existing front end bugs…Other significant improvements

  • The compiler’s --help command-line option has been extended so that it now takes an optional set of arguments. These arguments restrict the information displayed to specific classes of command-line options, and possibly only a subset of those options. It is also now possible to replace the descriptive text associated with each displayed option with an indication of its current value, or for binary options, whether it has been enabled or disabled.

    Here are some examples. The following will display all the options controlling warning messages:

          --help=warnings
        

    Whereas this will display all the undocumented, target specific options:

          --help=target,undocumented
        

    This sequence of commands will display the binary optimizations that are enabled by -O3:

          gcc -c -Q -O3 --help=optimizers > /tmp/O3-opts
          gcc -c -Q -O2 --help=optimizers > /tmp/O2-opts
          diff /tmp/O2-opts /tmp/O3-opts | grep enabled

« )

http://en.wikipedia.org/wiki/GNU_Compiler_Collection (« GCC was started by Richard Stallman in 1985. He extended an existing compiler to compile C. The compiler originally compiled Pastel, an extended, nonportable dialect of Pascal, and was written in Pastel. It was rewritten in C by Len Tower and Stallman,[4] and released in 1987[5] as the compiler for the GNU Project, in order to have a compiler available that was free software. Its development was supervised by the Free Software Foundation.« )

Posted in C++, Développement logiciel, GCC, java, programmation | Tagué: | Leave a Comment »

Connexion entre composants Java et DotNet: Ikvm, boo, java, .NET, ironpython

Posted by patrick sur décembre 15, 2007

Source: http://ironpython-urls.blogspot.com/2007/11/boo-java-net-and-ironpython.html

————————————————-<————————————

Thursday, November 15, 2007

Boo, Java, .NET and IronPython

A blogger called Tomo wondered about which .NET language to choose Boo (a mighty fine language) or IronPython. He came down in favour of Boo, and an interesting discussion ensued in the comments:

The very next thing he tried was taking the Java class library for SWT (the user interface library) and compiled them into a .NET dll with IKVM. He then used them from Boo and IronPython, which worked!

This is an interesting coincidence, as a few days ago Rodrigo announced on the Boo blog about boojay – a compiler that emits Java bytecode from Boo:

————————————————-8<———————————————

Source: http://blogs.codehaus.org/people/bamboo/archives/001623_introducing_boojay.html
(« A boo application using the SWT java GUI library. Thanks to IKVM that’s not only possible but very simple as well. So what’s the news? Well, Friday morning I was chatting with Klaus and he said to me « if you get boo to emit java bytecodes I’ll do all my stuff in boo ». How’s that for a challenge? 🙂 Thanks again to IKVM, ObjectWeb ASM and the extensible boo pipeline architecture boojay was born after a weekend of relaxed hacking « )

http://boo-extensions.googlecode.com/svn/trunk/boojay/ (« boojay is an attempt at getting the boo compiler to emit java bytecode. Architecture
Thanks to the amazing IKVM project it is possible to use the great ObjectWeb ASM library from boo running on mono/ms.net to emit native java bytecodes that can be executed by any compliant java virtual machine
« )

http://koans.tomo-online.com/2007/11/15/langage-frenzy/ (« Although I should be doing something else, Boo, IronPython and .NET kept occupying my mind. So I made a small coding experiment. First, I downloaded IKVM. Then – SWT. I compiled SWT jar to a dll. No problems here. Then I wrote a SWT hello world in IronPython. To be honest – I took a Java one from SWT website and rewrote line by line. I was surprised that my hello world ran without a glich! Next, I copied a HelloWorldSWT.py into HelloWorldSWT.boo and changed the import statement. Compiled (”By golly! No problems? No warnings?”) and run. And no problems again?? It started to look suspicious… Java run on .NET, calls from Java to native library, two different languages… and everything without a single warning? So I decided to take it to foreign territory… Ubuntu! I fired up a VMWare image with Ubuntu 6.10 (the linux vm I have handy), downloaded Linux SWT, compiled it to dll, copied HelloWorldSWT.exe from Windows along with some ikvm dlls and… no problems again! I’m really, really surprised how smooth the experiment was. Thumbs up! « )

http://en.wikipedia.org/wiki/IKVM (« IKVM.NET is an implementation of Java for Mono and the Microsoft .NET Framework. IKVM is free software, distributed under a permissive free software licence. IKVM includes the following components: for

  • A Java Virtual Machine implemented in .NET
  • A .NET implementation of the Java class libraries
  • Tools that enable Java and .NET interoperability

With IKVM you can run compiled Java code (bytecode) directly on Microsoft .NET or Mono. The bytecode is converted on the fly to CIL and executed. Jeroen Frijters is the main contributor to IKVM.NET. He is Technical Director of Sumatra Software, based in The Netherlands. As of June 2007, the machine supports Java 1.6 with the exception of AWT and Swing. IKVM uses OpenJDK as its class library. »)

http://www.ikvm.net/ (« ..The following projects are related to IKVM.NET in some way:

http://www.eclipse.org/swt/ (« SWT is an open source widget toolkit for Java designed to provide efficient, portable access to the user-interface facilities of the operating systems on which it is implemented.« )

http://www.gnu.org/software/classpath/classpath.html (« GNU Classpath, Essential Libraries for Java, is a GNU project to create free core class libraries for use with virtual machines and compilers for the java programming language. Classpath is still a work in progress. The first public release will be version 1.0. There have been no public releases; however, pre-release source code is available via GNU’s anonymous CVS server , and snapshots of the Classpath tree have been released and are available from ftp://ftp.gnu.org/gnu/classpath/« )

http://en.wikipedia.org/wiki/GNU_Classpath (« GNU Classpath is a project aiming to create a free software implementation of the standard class libraryJava programming language. Despite the massive size of the library to be created, the majority of the task is already done, including Swing, CORBA, and other major parts. The Classpath developers have implemented almost all of the classes from J2SE 1.4 and 5.0. Classpath can thus be used to run popular Java-based software such as Azureus and Eclipse. It is a part of the Free Software Foundation‘s GNU project and was launched so that computer users could use Java programs without giving up the freedoms which the free software movement works to secure. GNU Classpath was originally developed in parallel with libgcj due to license incompatibilities, but later merged...Since version 0.95, Java 1.5 additions like generics have been fully integrated into the main branch. The branch allows GCJ to use Eclipse compiler, ecj, to compile Java 1.5 source code to bytecode, which is then changed into native code by GCJ itself« )

http://en.wikipedia.org/wiki/Boo_programming_language (« Boo is an object oriented, statically typed programming language developed starting in 2003, which seeks to make use of the Common Language Infrastructure support for Unicode, internationalization and web style applications, while using a Python-inspired syntax and a special focus on language and compiler extensibility. Some features of note include type inference, generators, multimethods, optional duck typing, macros, true closures, currying, and first class functions. Boo is open sourcelicensed under an MIT/BSD style license.Boo can be used with Microsoft .NET or Mono. »)

https://pvergain.wordpress.com/2007/08/17/grasshopper-faire-tourner-des-applications-aspnet-sur-des-serveurs-j2ee/
(« Grasshopper 2.0 enables you to produce .NET Web and server applications that run on Linux & other Java-enabled platforms using ASP.NET 2.0 controls, role-based security, and C# generics. Check out our developer blogs, interop forums, code samples, and how-to articles to learn how« )

– http://blog.mainsoft.com/blog/net-java-interop-8-links-to-get-you-started/(« 

Posted in 2007, ASP.NET, Développement logiciel, DotNet, FSF, IDE-GUI, Ironpython, J2EE, java, JEE, python | Tagué: , , , | Leave a Comment »

Les nouveautés dans ASP.NET Extensions: ASP.NET MVC et ASP.NET AJAX

Posted by patrick sur décembre 15, 2007

Comme le précise ce billet http://dosimple.ch/articles/MVC-ASP.NET/ écrit le 2 mai 2006 et celui-ci écrit le 13 mars 2007, le framework ASP.NET n’incite pas particulièrement à la séparation stricte de type Modèle, Vue, Contrôleur. On a vu que Monorail, projet open source, implémente le modèle MVC. Microsoft emboite le pas avec un grand retard en introduisant ASP.NET MVC: voir le billet suivant: http://weblogs.asp.net/scottgu/archive/2007/10/14/asp-net-mvc-framework.aspx (« One of the things that many people have asked for over the years with ASP.NET is built-in support for developing web applications using a model-view-controller (MVC) based architecture. Last weekend at the Alt.NET conference in Austin I gave the first public demonstration of a new ASP.NET MVC framework that my team has been working on. You can watch a video of my presentation about it on Scott Hanselman’s blog here.

What is a Model View Controller (MVC) Framework?

MVC is a framework methodology that divides an application’s implementation into three component roles: models, views, and controllers.

  • « Models » in a MVC based application are the components of the application that are responsible for maintaining state. Often this state is persisted inside a database (for example: we might have a Product class that is used to represent order data from the Products table inside SQL).

  • « Views » in a MVC based application are the components responsible for displaying the application’s user interface. Typically this UI is created off of the model data (for example: we might create an Product « Edit » view that surfaces textboxes, dropdowns and checkboxes based on the current state of a Product object).

  • « Controllers » in a MVC based application are the components responsible for handling end user interaction, manipulating the model, and ultimately choosing a view to render to display UI. In a MVC application the view is only about displaying information – it is the controller that handles and responds to user input and interaction.

One of the benefits of using a MVC methodology is that it helps enforce a clean separation of concerns between the models, views and controllers within an application. Maintaining a clean separation of concerns makes the testing of applications much easier, since the contract between different application components are more clearly defined and articulated.

The MVC pattern can also help enable red/green test driven development (TDD) – where you implement automated unit tests, which define and verify the requirements of new code, first before you actually write the code itself.

A few quick details about the ASP.NET MVC Framework

I’ll be doing some in-depth tutorial posts about the new ASP.NET MVC framework in a few weeks once the bits are available for download (in the meantime the best way to learn more is to watch the video of my Alt.net presentation).

A few quick details to share in the meantime about the ASP.NET MVC framework:

  • It enables clean separation of concerns, testability, and TDD by default. All core contracts within the MVC framework are interface based and easily mockable (it includes interface based IHttpRequest/IHttpResponse intrinsics). You can unit test the application without having to run the Controllers within an ASP.NET process (making unit testing fast). You can use any unit testing framework you want to-do this testing (including NUnit, MBUnit, MS Test, etc).

  • It is highly extensible and pluggable. Everything in the MVC framework is designed so that it can be easily replaced/customized (for example: you can optionally plug-in your own view engine, routing policy, parameter serialization, etc). It also supports using existing dependency injection and IOC container models (Windsor, Spring.Net, NHibernate, etc).

  • It includes a very powerful URL mapping component that enables you to build applications with clean URLs. URLs do not need to have extensions within them, and are designed to easily support SEO and REST-friendly naming patterns. For example, I could easily map the /products/edit/4 URL to the « Edit » action of the ProductsController class in my project above, or map the /Blogs/scottgu/10-10-2007/SomeTopic/ URL to a « DisplayPost » action of a BlogEngineController class.

  • The MVC framework supports using the existing ASP.NET .ASPX, .ASCX, and .Master markup files as « view templates » (meaning you can easily use existing ASP.NET features like nested master pages, <%= %> snippets, declarative server controls, templates, data-binding, localization, etc). It does not, however, use the existing post-back model for interactions back to the server. Instead, you’ll route all end-user interactions to a Controller class instead – which helps ensure clean separation of concerns and testability (it also means no viewstate or page lifecycle with MVC based views).

  • The ASP.NET MVC framework fully supports existing ASP.NET features like forms/windows authentication, URL authorization, membership/roles, output and data caching, session/profile state management, health monitoring, configuration system, the provider architecture, etc. »)

A voir:

  • https://pvergain.wordpress.com/2007/03/13/critique-de-larchitecture-aspnet/ (« Le problème avec ASP. Net est qu’il n’y a qu’un objet qui traite les demandes http, c’est l’objet PAGE. C’est lui qui a le contrôle de tout, et donc il mélange le code dit de «contrôle», et le code qui pilote la «visualisation» des éléments en html. Et bien souvent, on mélange aussi le code qui pilote le «Modèle» c’est à dire l’obtention des données directement depuis la base de données avec Ado.Net (c’est ce qu’on obtient lorsqu’on fait du WYSIWYG dans Visual Studio en choisissant les Sql Data Source et les glissant-déposant sur l’ihm). Cet anti-modèle (ou anti–pattern) a été souvent pointé du doigt par les architectes et développeurs, car en plus de faire produire du code spaghetti (bien que orienté objet), il rend impossible les tests systématisés (automatisés).« )
  • http://dosimple.ch/articles/MVC-ASP.NET/ (« Dans le framework ASP.NET la vue est un fichier HTML agrémenté de balises ASP. Le contrôleur et le modèle sont en général mélangés dans un objet qui dérive de la classe System.Web.UI.Page. »)
  • http://www.castleproject.org/monorail/index.html (« MonoRail is a MVC Web Framework inspired by Action Pack. MonoRail differs from the standard WebForms way of development as it enforces separation of concerns; controllers just handle application flow, models represent the data, and the view is just concerned about presentation logic. Consequently, you write less code and end up with a more maintainable application. Although the project name is MonoRail, we do not have any affiliation with the Mono project. MonoRail runs on Microsoft .Net 1.1, 2.0 and Mono.« )
  • http://en.wikipedia.org/wiki/ASP.NET_MVC_Framework (« ASP.NET MVC Framework is a Model-view-controller framework which Microsoft is adding to ASP.NET. It allows an application to be built as a composition of three roles: Model, View and Controller. A Model represents the state of a particular aspect in the application. Frequently, a model maps to a database table, with the entries in the table representing the state of the table. A Controller handles interactions and updates the model to reflect a change in state of the application. A View ASP.NET MVC Framework couples the models, views and controllers using interface-based contracts, thereby allowing each component to be easily tested independently. The view engine in the MVC framework uses regular .aspx pages to design the layout of the UI pages onto which the data is composed; however any interactions are routed to the controllers rather than using the postback mechanism. Views can be mapped to REST-friendly URLs. ASP.NET MVC Framework has been launched as a Community Technology Preview on December 10, 2007 extracts necessary information from a model and renders a UI to display that.. »)
  • http://www.hanselman.com/blog/ScottGuMVCPresentationAndScottHaScreencastFromALTNETConference.aspx ( » I attended the ALT.NET Conference last weekend in Austin, TX. I personally find the name « Alt » as in « Alternative » too polarizing and prefer terms like « Pragmatic.NET » or « Agile.NET. » At the conference I suggested, partially in jest, that we call it « NIH.NET » as in « Not Invented Here.NET. » 😉 Ultimately this is a group that believes in:
    • Continuous Learning
    • Being Open to Open Source Solutions
    • Challenging the Status Quo
    • Good Software Practices
    • DRY (Don’t Repeat Yourself)
    • Common Sense when possible.

    ScottGu gave an hour long presentation on the upcoming MVC Framework and I took some guerilla video. ScottGu’s presentation is here in Silverlight and it’s about 60 minutes long. Considering it’s so long, the video squished nicely. This was the first time the MVC Framework was shown publicly. Note that this was a Prototype, not the Production code and both ScottGu and I make that point a number of times to drive home that it’s early. Some of the code was written on a plane, just to give you an idea. After The Gu did his piece on the MVC Framework, I showed some prototype hacking that I’d done over the previous few days along with some work Phil Haack did. My presentation is here as Silverlight and it’s about 30 minutes long. I showed the Model View Controller with Controllers in IronPython and an IronPython view using a WebFormViewEngine. Then I talked about the possibilities of alternate ViewEngines and showed Phil Haack’s prototype RubyViewEngine. »)

  • http://weblogs.asp.net/scottgu/archive/2007/11/13/asp-net-mvc-framework-part-1.aspx ( » ASP.NET MVC Framework (Part 1) I’m going to use a simple e-commerce store application to help illustrate how the ASP.NET MVC Framework works. For today’s post I’ll be implementing a product listing/browsing scenario in it. Specifically, we are going to build a store-front that enables end-users to browse a list of product categories when they visit the /Products/Categories URL on the site>>Since it adds a testing project, does this require Team System? No – the good news is that Test Projects with VS 2008 are now supported with the VS 2008 Professional edition – and no longer require team system. You will also be able to use the VS Express and Standard edition products as well, and then use NUnit, MBUnit or some other testing framework with them (we’ll ship project templates for these as well…>> 2. Is it also possible to have this URL mapped: /Products/Beverages/3 instead of /Products/Beverages?page=3 or does it _need_ the parameter name? Yes – this is totally supported. Just set a route rule for /Products/Beverages with the format /Products/<Category>/<Page> – they’ll then get passed in as arguments to the action method:public List(string category, int? page) {}>>Also, some ideas and general remarks: 1. I’d love to see more helper methods for use in the views, I like how Ruby on Rails has many shortcuts for creating forms and formfields etc. Yes – we’ll have a rich library of helper methods for the views. They’ll include helpers to create all the standard forms, formfields and more.

>>2. Migrations! Not a part of MVC but from my experience with Ruby on Rails I would love to see support for this somewhere, anywhere! It would fit perfectly with the more agile way of developing that is possible with ASP.NET MVC. Rob Conery is building .NET Migrations support as part of the SubSonic project, and recently joined Microsoft. You’ll be able to use this with ASP.NET MVC

>>I’m also very keen to get my hands on the CTP. Scott, you mention, using Inversion of Control containers with the MVC framework. I’d be very interested in seeing a blog post on this subject. Also, will there be a sample application (with tests and IoC) available alonside the CTP? We have a IControllerFactory extensiblity point that owns creating Controller instances. You can use this with a IOC container to customize any Controller instance prior to it being called by the MVC framework. We’ll be posting samples of how to use this with ObjectBuilder and Windsor with the first CTP I believe

>> Very cool! One thing I’d like to see guidance on is developing MVC apps with multiple UIs. You say here that it’s best to put your models and controllers in the web app, but say we want a Winforms, WPF, Silverlight, and Web UI all doing similar things. Or a Mobile Web UI and Desktop Web UI… Would these still each need their own Models and Controllers, or does it make sense to have one library that they all share? If so, how is that supported? I’m still new to MVC, so if I’m missing something conceptually here, tell me! That is a good question, and one we’ll need to provide more guidance on in the future. In general it is often hard to share the same controller across both client and web UI, since the way you do data access and the stateful/stateless boundaries end up being very different. It is possible – but some guidance here would ceretainly be useful. My team should hopefully be coming out with this in the future

>>I really appreciate this material. Do you support the MVC pattern over the MVP pattern? Or are there just better scenarios for using each? The above approach I showed uses a MVC based pattern – where the Controller and the View tend to be more separate and more loosly coupled. In a MVP pattern you typically drive the UI via interfaces. This works well with a controls model, and makes a lot of sense with both WinForms and WebForms where you are using a postback model. Both MVC and MVP are perfectly fine approaches to use. We are coming out with the MVC approach for ASP.NET partly because we’ve seen more demand for it recently for web scenarios…

>> When can we expect a similar chapter with SubSonic as the DAL and scaffolding provider? (see http://oakleafblog.blogspot.com/2007/11subsonic-will-be-toolset-for-microsofts.html I’ll be covering scaffolding in a future blog post. LINQ to SQL scaffolding is built-in with ASP.NET MVC and doesn’t require SubSonic. SubSonic will also obviously be adding new ASP.NET MVC features as well.

>> My applications in .NET works with « 3 layers » pattern (business logic and data access in your own dll). How can i use this wonderfull MVC with my Models (data access) and Controllers (B.Logic)?? Because if i’m not reuse this, i’ve repeat code in every layer; then this MVC is not DRY (don’t repeat yourself) and the community don’t accept. There is no need to put your business and data logic in the same assembly as your controllers. You can split them up across multiple class library projects if you prefer

>> Does this mean that with MVC, we no longer use LinqDatasource in the View section? While the LinqDataSource control will technically work in MVC Views, if you are using a MVC model you wouldn’t want to place it there. Instead you want to perform all of your data and application logic in the Controller layer – and then pass the needed data to the view.

>> Perhaps I missed it somehow, but can you explain on which version of asp.net will this ctp run? The MVC framework builds on top of .NET 3.5

>> Scott, this is amazing timing! The URL mapping features inherit in an MVC application are PERFECT for the upgrade to ASP.NET 3.5 I’m making to my spelldamage.com site. Hosting question, will hosts simply need to support the ASP.NET 3.5 framework to allow us to run ASP.NET MVC applications? Your hoster will need to support .NET 3.5 for the MVC support.

>> Is’nt the MVC framework, in fact the Controller, implementation of the Front Controller pattern? Yes – the ASP.NET MVC framework uses a front-controller pattern. »)

  • http://weblogs.asp.net/scottgu/archive/2007/12/03/asp-net-mvc-framework-part-2-url-routing.aspx (« Last month I blogged the first in a series of posts I’m going to write that cover the new ASP.NET MVC Framework we are working on. The first post in this series built a simple e-commerce product listing/browsing scenario. It covered the high-level concepts behind MVC, and demonstrated how to create a new ASP.NET MVC project from scratch to implement and test this e-commerce product listing functionality. In today’s blog post I’m going to drill deeper into the routing architecture of the ASP.NET MVC Framework, and discuss some of the cool ways you can use it for more advanced scenarios in your application… What does the ASP.NET MVC URL Routing System do? The ASP.NET MVC framework includes a flexible URL routing system that enables you to define URL mapping rules within your applications. The routing system has two main purposes:
    • Map incoming URLs to the application and route them so that the right Controller and Action method executes to process them
    • Construct outgoing URLs that can be used to call back to Controllers/Actions (for example: form posts, <a href= » »> links, and AJAX calls)

Having the ability to use URL mapping rules to handle both incoming and outgoing URL scenarios adds a lot of flexibility to application code. It means that if we want to later change the URL structure of our application (for example: rename /Products to /Catalog), we could do so by modifying one set of mapping rules at the application level – and not require changing any code within our Controllers or View templates.

>> BTW, can you explain in short about the Active Record Type support in our MVC.

.NET 3.5 has LINQ to SQL built-in – which is a great ORM. LINQ to Entities will also be built-into .NET 3.5 in the future (it also ships with the MVC setup). The MVC framework doesn’t require LINQ to SQL or LINQ to Entities as the data model – it also works with NHibernate, LLBLGen, SubSonic, DataSets, DataReaders, and/or any other data model with .NET. We will, though, provide out of the box scaffolding support for LINQ to SQL and LINQ to Entities that delivers nice integration with the MVC support.

>> Question : What is this MockHttpContext in the UnitTest class? I mean, i can guess what it is .. but is it new in .NET 3.5 or the MVC framework? The MockHttpContext is an example mock object. It isn’t currently built-in with the MVC framework (with the first preview you’d need to create this yourself). I’m hoping that before the MVC framework ships, though, that there are a built-in set of mock objects and test helpers that you can use out of the box (without having to mock them yourself). Note that all core contracts and types with the MVC framework are mockable (non-sealed and interfaces). So you can also use any existing Mock framework to test it (RhinoMocks, TypeMock, etc).

>> 1) Is it possible to use routes with a file extension if I don’t want to enable wildcard script mappings? For example, /Products/List/Beverages.rails or /Products/Detail/34.rails ? Yes – this is fully supported. We recommend changing your route rule to /[controller].mvc/[action]/[id]. When you install the ASP.NET MVC Framework we automatically register this .mvc extension – although you are free to use any other one you want.

>> Hypothetically, do you think it would be possible to customise the route creation process so that route data could be gathered from attributes on actions? We don’t currently support this built-in, but hypothetically you could load all the controllers at app-startup and use reflection on them to calculate the route rules. This would enable the scenario you are after.

>> Is it possible to use IronRuby as the coding language to target the MVC framework?? Yes – we’ll support both IronRuby and IronPython with the ASP.NET MVC Framework.

>> I am liking this more and more. I can see how the routing configuration code in global.asax.cs could become quite large. In my application, I can see dozens, maybe hundreds of unique routing rules. Is there any way this configuration can be put in a file somewhere? That file would be read on Application start. Seems like that would make deployment of routing changes easier, too. We don’t currently have a pre-built file format for reading in mapping rules. But it should be relatively easy to build (you could even use LINQ to XML to read in and construct the rules).

>> Just out of curiosity where in the HttpApplication cycle are the routing rules evaluated and are they exposed in any way to the rest of the HttpApplication cycle? My current security system grants permissions at what would become the controller-action level so if the route determination is made early enough I’d really like to drive my authorization off of it.
The routing rules are resolved after the OnPostMapRequestRequestHandler event. This means that it will happen *after* your authorization rules evaluate. The good news is that this means you should be able to re-use your existing security system as-is.

>> Will there be any way to use an XML document to create the routing rules outside of the Global.asax code? Yep – this scenario will be supported.

>> I noticed that in Django, you have to repeat yourself kind of often when you have a deep nested hierarchy of pages. Your search & search-results pages seem to be continuing that trend. I’m sure I could come up with some hierarchical data structure which can be serialized into Route objects, but is the ASP.NET team planning anything along those lines that would come stock?

With our first preview the Route type is not extensible (you can’t subclass it) – which means you sometimes need to register multiple routes for a series of things. For the next preview we are looking at enabling Route to be sub-classed – in which case you could easily encapsulate multiple URL mappings into a single registration.

>> Have you thought about being able to define a regular expression for url matching and using backreferences or named captures as the tokenized url? I think this would allow for much more flexibility while keeping the list of routing rules down to a minimum.

Yes – this is something we are looking at. The challange with regular expressions is that only a subset of people really understand them (and importantly – understand how to optimize them). But I agree that having this as an option would be super flexible.

>> I must say that i am still worried about having to leave all the knowledge that we ave until now with webforms and start a new technology and still think that we would need some kind of a bridge to close the gap between today solution of webforms and tomorrow solution of MVC. Although the way you structure application flow will be different, I think you’ll be pleasantly surprised by the amount of knowledge overlap that exists. Authentication, Authorization, Caching, Configuration, Compilation, Session State, Profile Management, Health Monitoring, Administration, Deployment, and many, many other things are exactly the same. MVC views are also .aspx pages (that use .ascx user controls and .master files). So the concept re-use is quite heavy there as well. »)

  • http://weblogs.asp.net/scottgu/archive/2007/12/06/asp-net-mvc-framework-part-3-passing-viewdata-from-controllers-to-views.aspx (« The last few weeks I have been working on a series of blog posts that cover the new ASP.NET MVC Framework we are working on. The ASP.NET MVC Framework is an optional approach you can use to structure your ASP.NET web applications to have a clear separation of concerns, and make it easier to unit test your code and support a TDD workflow. The first post in this series built a simple e-commerce product listing/browsing site. It covered the high-level concepts behind MVC, and demonstrated how to create a new ASP.NET MVC project from scratch to implement and test this e-commerce product listing functionality. The second post in this series drilled deep into the URL routing architecture of the ASP.NET MVC framework, and discussed both how it worked as well as how you can handle more advanced URL routing scenarios with it. In today’s blog post I’m going to discuss how Controllers interact with Views, and specifically cover ways you can pass data from a Controller to a View in order to render a response back to a client. In Part 1 of this series, we created an e-commerce site that implemented basic product listing/browsing support. We implemented this site using the ASP.NET MVC Framework, which led us to naturally structure the code into distinct controller, model and view components. When a browser sends a HTTP request to our web site, the ASP.NET MVC Framework will use its URL routing engine to map the incoming request to an action method on a controller class to process it. Controllers in a MVC based application are responsible for processing incoming requests, handling user input and interactions, and executing application logic based on them (retrieving and updating model data stored in a database, etc). When it comes time to render an HTML response back to the client, controllers typically work with « view » components – which are implemented as separate classes/templates from the controllers, and are intended to be focused entirely on encapsulating presentation logic. Views should not contain any application logic or database retrieval code, instead all application/data logic should only be handled by the controller class. The motivation behind this partitioning is to help enforce a clear separation of your application/data logic from your UI generation code. This makes it easier to unit test your application/data logic in isolation from your UI rendering logic.Views should only render their output using the view-specific data passed to it by the Controller class. In the ASP.NET MVC Framework we call this view-specific data « ViewData ». The rest of this blog post is going to cover some of the different approaches you can use to pass this « ViewData » from the Controller to the View to render.

>> One question Scott: Let say i’m jumpng on MS MVC bandwagon, do i have to abandon asp.net Page Life cycle godddies, should i set up my mind to different approach. When you use the ASP.NET MVC approach you’ll want to have all post in your site go to your Controller. This helps ensure that the application can be easily tested and preserves the separation of concerns. This is different from using ASP.NET server controls which postback to themselves (which is very powerful too – but means that it can sometimes be slightly harder to test). What doesn’t change is that all of other ASP.NET pieces (forms authentication, role management, session state, caching, profiles, configuration, compilation, httprequest/response, health monitoring, etc, etc) works with both web forms based pages and MVC based pages. MVC UI are also built with .aspx, .master, and .ascx files – so there is a high level of skill re-use there as well.

>> Some asp.net controls require <form runat=server>. If we use a asp:dropdownlist for example, we have to place in the asp:form. And this means viewstate comes back! Is there any way to get rid of hidden form fields? Or you suggest that we do must use classic HTML controls ? I’ll cover this more in my next blog in this series. We have helpers that can automate generating things like dropdownlists, etc. Think of them as controls for MVC. These don’t use viewstate and give you a little more control over the output of your HTML.

>> It would be nice if you can just compare a bit our MVC with ROR. Within ROR, we can create tables, Columns and Rows with Ruby, without using a single line of SQL, and all its done through ActiveRecord. In short all CRUD advantages.

>> SubSonic is almost in this line. Can you explain more in this line or how SubSonic can be used to take ActiveRecord Type advantages.

RoR is made up of several components.

« Action Controller » is the name of the MVC framework that Rails uses. That is the closest analogy to the ASP.NET MVC Framework – and at a high-level the ASP.NET MVC framework uses many of the same core concepts (URLs map to controller actions). The ASP.NET MVC Framework has a few additional features (like the ability to map incoming parameters directly to action method parameters). It is also more explicit about calling RenderView within the request.

« Active View » is the name of the View engine that Rails uses. This is analagous to the .aspx/.master/.ascx infrastructure ASP.NET has. Our view engine is IMO a little richer, and supports several additional features (declarative controls/components, templating, multiple regions for nested master pages, WYSIWYG designer, strongly typed ViewData access, pluggable storage provider, declarative localization, etc).

« Active Record » is the name of the ORM (object relational mapper) that RoR uses. This is analagous to an ORM in the .NET world – whether it is LINQ to SQL, LINQ to Entities, LLBLGen, SubSonic, NHibernate, ActiveRecord (the .NET version), etc. All of these ORMs have ways to map rows and columns in a database to objects that a developer then manipulates and works against (and can save changes back). The LINQ to SQL ORM is built-in to .NET 3.5 today, and LINQ to Entities will be built-in with .NET 3.5 SP1.

I think from your follow-up question above you are referring specifically to the « migrations » feature in RoR – which allows you to define table schemas using code, and version the schemas forward/backward. There isn’t a built-in version of this in the core .NET Framework today – although the SubSonic project has recently released a version that allows you to-do this using .NET. You can find out more about it here: www.subsonicproject.com.

>> Superb, …but I still longing for the IOC integration (Spring.NET, Windsor, StructureMap)…maybe in the next post ? I am planning on posting about IOC and dependency injection in the future (the ASP.NET MVC framework fully supports it and can be used with Spring.NET, Windsor, StructureMap, etc). I have a few other more basic MVC tutorials I need to get out of the way first – but testing and dependency injection are on the list for the future.

>> Nice series, eagerly waiting to see AJAX approach in the new ASP.NET MVC Framework, so when shall we expext that.
We will have ASP.NET AJAX support with the ASP.NET MVC Framework. I’ll talk more about this in a future tutorial series post.

>> This is coming together nicely. I was just hoping you might explain why there are 3 different ways to pass the ViewData? Does each method offer something that the others don’t? If not, surely it would be best to choose one method and force all developers to follow the same practice? Conceptually there are two ways to pass viewdata – either as a dictionary, or as a strongly typed object. In general I recommend using the strongly typed dictionary approach – since this gives you better compilation checking, intellisense, and refactoring support. There are, however, some times when having a more latebound dictionary approach ends up being flexible for more dynamic scenarios« )

  • http://blog.wekeroad.com/2007/10/26/microsoft-subsonic-and-me/ (« Rather than try and come up with some lame metaphors and trite pop-culture references, I’ve decided to use some advice from English 101 Professor:

    “Whatever the hell you’re trying to say, just say it”

    So I will: I’m going to work for Microsoft. I just signed the offer letter. I’ll be working with the ASP.NET guys on the new MVC platform as well as some other groovy things like Silverlight. I get to work “across the hall” from one of my very good friends – Phil Haack. I think it’s worth pointing out that SubSonic hasn’t been “bought”. Some might smell a conspiracy here, but I’ll leave that to the X-Files and Cap’n Crunch crowd to drum up all the evil reasons why the mothership has “beamed me up”. SubSonic will remain under the same MPL 1.1 license it always has, and will remain as completely Open Source as it always has – nothing will change at all. I’m just getting paid, essentially, to work on it 🙂...This is crucial to me. I decided to be direct with him and make sure we both understood these important points:

    “I want to be sure I have complete creative control over SubSonic, and that you don’t censor my blog… is that cool?”

    Shawn’s response is why I took the job:

    “Well Duh…” (he added some more things that were a bit more eloquent than “duh” – but I don’t think I was listening).

    I can make jokes about the UAC on my blog? And make up fictional Matrix converstations with ScottGu? Sign me up! I start on November 12th, right after DevConnections in Vegas (come on by if you’re out that way at the DNN Open Force« )

  • http://www.subsonicproject.com/ (« A Super High-fidelity Batman Utility Belt. SubSonic works up your DAL for you, throws in some much-needed utility functions, and generally speeds along your dev cycle. Why SubSonic ? Because you need to spend more time with your friends, family, dog, bird, cat… whatever. You work too much. Coding doesn’t need to be complicated and time-consuming. »)
  • http://en.wikipedia.org/wiki/Test-driven_development (« Test-Driven Development (TDD) is a software development technique consisting of short iterations where new test cases covering the desired improvement or new functionality are written first, then the production code necessary to pass the tests is implemented, and finally the software is refactored to accommodate changes. The availability of tests before actual development ensures rapid feedback after any change. Practitioners emphasize that test-driven development is a method of designing software, not merely a method of testing. Test-Driven Development began to receive publicity in the early twenty-first century as an aspect of Extreme Programming, but more recently is creating more general interest in its own right. Along with other techniques, the concept can also be applied to the improvement and removal of software defects from legacy code that was not developed in this way . »)
  • ss
  • http://weblogs.asp.net/scottgu/archive/2007/12/09/asp-net-mvc-framework-part-4-handling-form-edit-and-post-scenarios.aspx
  • (« ASP.NET MVC Framework (Part 4): Handling Form Edit and Post Scenarios   The last few weeks I have been working on a series of blog posts that cover the new ASP.NET MVC Framework we are working on.  The ASP.NET MVC Framework is an optional approach you can use to structure your ASP.NET web applications to have a clear separation of concerns, and make it easier to unit test your code and support a TDD workflow. The first post in this series built a simple e-commerce product listing/browsing site.  It covered the high-level concepts behind MVC, and demonstrated how to create a new ASP.NET MVC project from scratch to implement and test this e-commerce product listing functionality.  The second post drilled deep into the URL routing architecture of the ASP.NET MVC framework, and discussed both how it worked as well asthird post discussed how Controllers interact with Views, and specifically covered ways you can pass view data from a Controller to a View in order to render a response back to a client.  In today’s blog post I’m going to discuss approaches you can use to handle form input and post scenarios using the MVC framework, as well as talk about some of the HTML Helper extension methods you can use with it to make data editing scenarios easierClick here to download the source code for the completed application we are going to build below to explain these concepts… Our Data Model. We are going to use the SQL Server Northwind Sample Database to store our data.  We’ll then use the LINQ to SQL object relational mapper (ORM) built-into .NET 3.5 to model the Product, Category, and Supplier objects that represent rows in our database tables. We’ll begin by right-clicking on our /Models sub-folder in our ASP.NET MVC project, and select « Add New Item » -> « LINQ to SQL Classes » to bring up the LINQ to SQL ORM designer and model our data objects…To learn more about LINQ and LINQ to SQL, please check out my LINQ to SQL series here The HtmlHelper object (as well as the AjaxHelper object – which we’ll talk about in a later tutorial) have been specifically designed to be easily extended using « Extension Methods » – which is a new language feature of VB and C# in the VS 2008 release.  What this means is that anyone can create their own custom helper methods for these how you can handle more advanced URL routing scenarios with it.  The objects and share them for you to use. We’ll have dozens of built-in HTML and AJAX helper methods in future previews of the ASP.NET MVC Framework.  In the first preview release only the « ActionLink » method is built-into System.Web.Extensions (the assembly where the core ASP.NET MVC framework is currently implemented).  We do, though, also have a separate « MVCToolkit » download that you can add to your project to obtain dozens more helper methods that you can use with the first preview release.
  • >> This is nice. But do you handle subcomponents? subviews? Is view reuse possible inside other view? This is very important for even for modest sized applications? How would you handle posts correcly inside of subviews 😉 ?The first public MVC preview doesn’t have the concept of SubControllers yet (where you can attach them for regions of a larger view).  That is something we have planned for to tackle soon though.

    >> However, liviu raises good questions about Sub-Controllers, Composite Views and AJAX scenarios. How Will the MVC framework address the complex wiring of different parts of a page to different controllers for async updates?? My brain hurts thinking about it, yet I have implement these portal pages all the time cos our customers demand it. The first ASP.NET MVC Preview allows you to call RenderView (for example: RenderView(« Edit »)) and have it apply to either a .aspx viewpage or a .ascx viewusercontrol.  This ends up being really useful for scenarios where you are doing AJAX callbacks and want to refresh a portion of a page.  These callbacks could either be to the same Controller that rendered the origional page, or to another Controller in the project. We don’t have all the AJAX helper methods yet for this – but you could roll them yourself today.  We’ll obviously be releasing an update that does include them in the future.

  • >> Can you provide an example of how we might use a server side control to generate the drop down list or a textbox (a la WebForms) along with the pro’s and con’s of each approach? Personally, I do not like the old ASP <%= … %> syntax; but if there is a good reason to use it then I am willing to change that opinion. The main reason I showed the <% %> syntax in this post was that we don’t have the server-side MVC control equivalents available yet for this dropdown and text scenario.  That is on our roadmap to-do though – at which point you don’t need to necessarily use the <% %> syntax. In general what we’ve found is that some developers hate the <% %> syntax, while others prefer it (and feel that controls get in the way).  We want to make both sets of developers happy, and will have options for both. 🙂
  • >> Great work on the MVC model, it is a clean and intuitive model that appears to scale well. My only recommendation is that your actions (verbs) appear after the ids (nouns), e.g. [Controller]/[Id]/[Action]/  That would keep the architecture noun focused, opposed to verb focused. With this approach you can easily build an administrative interface on a public read-only site by adding verbs such as /edit/ or /delete/ at the end of your URL. A simple security rule can be added to the Controller that says ignore all Verbs after a noun, such as category or product, if user is not part of an administrative group. Thanks for the suggestion Josh.  You can do this today by creating your own custom route registration.  In the next preview I believe Route will be extensible so that you could also create a single resource route that supports these semantics.>> I was wondering if we could get an idea of the official « roadmap » for asp.net mvc?  Specifically, I’d like to know what features the team plans to release on what dates … ultimately, when this thing will RTM.  As I’ll be evaluating mvc and monorail for an upcoming app, this kind of information would really be helpful in determining which direction to go. We don’t have a formally published roadmap just yet – we will hopefully publish one early next year though.« )
  • http://en.wikipedia.org/wiki/ASP.NET_AJAX (« ASP.NET AJAX, formerly code-named Atlas, is a set of extensions to ASP.NET developed by Microsoft for implementing Ajax functionality. Including both client-side and server-side components, ASP.NET AJAX allows the developer to create web applications in ASP.NET 2.0 (and to a limited extent in other environments) which can update data on the web page without a complete reload of the page. The key technology which enables this functionality is the XMLHttpRequest object, along with Javascript and DHTML. ASP.NET AJAX was released as a standalone extension to ASP.NET in January 2007 after a lengthy period of beta-testing. It was subsequently included with version 3.5 of the .NET Framework, which was released alongside Visual Studio 2008 in November 2007.« )

Posted in 2007, Acces aux données, active record, AJAX, Architecture logicielle, ASP.NET, Développement logiciel, design pattern, DotNet, IDE-GUI, Ironpython, javascript, open source, ORM, RIA, ruby, tests, Web Frameworks | Tagué: , , , , , , , | Leave a Comment »

Les dernières nouvelles du monde DotNet : ADO.NET Data services, LINQ, Mono 1.2.6, Visual studio 2008, silverlight2.0

Posted by patrick sur décembre 13, 2007

En vrac:

ADO.NET Data Services (Astoria Project)

  • http://astoria.mslivelabs.com/ (« The new wave of web applications are built on technologies such as AJAX and Microsoft Silverlight that enable developers to build better, richer user experiences. These technologies bring a shift in how applications are organized, including a stronger separation of presentation from data. ADO.NET Data Services (also known as Project code name “Astoria”) consists of a combination of patterns and libraries that enables any data store to be exposed as a flexible data service, naturally integrating with the Web, that can be consumed by Web clients within a corporate network or across the Internet. ADO.NET Data Services uses URIs to point to pieces of data and simple, well-known formats to represent that data, such as JSON and ATOM/APP. This results in data being exposed to Web clients as a REST-style resource collection, addressable with URIs that agents can interact with using standard HTTP verbs such as GET, POST, or DELETE. » Je rajoute un bémol à la dernière phrase qui est inexacte: DELETE n’est pas un verbe HTTP. Pour rappel voir le billet que j’avais écrit à propos de Django: The method of an HTML form is limited to GET and POST. PUT and DELETE are not allowed. This isn’t some failure of browser vendors to properly implement the specification either. The HTML specification only allows GET and POST as form actions. XHTML and even XForms 1.0 don’t change this. This means it’s impossible to build a fully RESTful client application inside a web browser. Consequently everyone tunnels everything through POST, and simply ignores PUT and DELETE)

LINQ

  • http://tirania.org/blog/archive/2007/Oct-24.html (« OpenSource LINQ providers: The Db_Linq is an open source project to create a LINQ provider for other databases. The project is lead by George Moudry and so far has providers for PostgreSQL, Oracle and Mysql. George keeps a blog http://code2code.net/wordpress/ where you can track the development of DbLinq. Thanks to Bryan for pointing me out to this fantastic piece of code. Mono users on Linux will now be able to use LINQ with open source databases from C# (in addition to our in-memory and XML providers). Update: A nice blog entry talks about Parallel LINQ. A version of LINQ that can be used to parallelize operations across multiple CPUs:

    IEnumerable data = …;

    // Regular code:
    var q = data.Where(x => p(x)).
    Orderby(x => k(x)).Select(x => f(x));
    foreach (var e in q) a(e);

    // Parallelized version, add the « AsParallel » method:
    var q = data.AsParallel().Where(x => p(x)).
    Orderby(x => k(x)).Select(x => f(x))

    See more details about the above in the Running Queries On Multi-Core Processors article.« )

  • http://spellcoder.com/blogs/bashmohandes/archive/2007/10/14/8530.aspx (« I’ve been hearing about PLINQ (Parallel Linq) since the first days of announcing LINQ, the idea of making use of the new functional style programming provided in DotNet 3.5 in order to give better performance on Multi Core machines, the idea sounds cool since first day, and it now comes true in a new name Parallel FX or PFX. The programming model provided is quite simple and utilizes the same LINQ model, the new assembly is called System.Concurrency.dll which is the library that contains the new interface called IParallelEnumerable<T>, also it adds an extension methods for all collections and arrays that implement old IEnumerable, the extension method is called AsParrallel<T> which converts any collection to a Parallel enabled collection of type IParallelEnumerable<T> »)
  • http://en.wikipedia.org/wiki/Language_Integrated_Query (« Language Integrated Query (LINQ, pronounced « link ») is a Microsoft .NET Framework component that adds native data querying capabilities to .NET languages using a syntax reminiscent of SQL. Many of the concepts that LINQ has introduced were originally trialled in Microsoft’s research project. LINQ has been released as a part of of .NET Framework 3.5 on November 19, 2007. »)

Visual Studio 2008

Mono

  • http://www.mono-project.com/news/archive/2007/Dec-12.html (« We have just released Mono 1.2.6. Some of the highlights for this release include:
    • Native Windows.Forms driver for MacOS X allows Winforms-based applications to run without an X server.
    • Support for the ASP.NET AJAX APIs and controls.
    • Support for FastCGI deployments: ASP.NET can now be deployed on a multitude of servers that implement the FastCGI protocol (lighttpd for example) in addition to Apache.
    • Windows.Forms now supports the WebControl on Windows and Linux using Mozilla.
    • Runtime will now consume much less memory for 2.0-based applications due to various optimizations in generics support as well as including many new performance improvements and an updated verifier and an implementation of CoreCLR security.
    • C# compiler is quickly approaching full 3.0 support, most of the basics work right now (except support for System.Query.Expression AST generation).
    • Mono 1.2.6 can now be used as an SDK for creating Silverlight 1.1 applications on all platforms. This allows developers to create applications that target Silverlight without requiring a Windows installation.« )

silverlight

ironpython

  •  http://ironpython-urls.blogspot.com/2007/12/ironpython-studio-now-available.html ( » IronPython Studio is a free full IDE (Integrated Development Environment) for the Python programming language. It is based on the existing IronPython example that is included in the VS SDK. IronPython Studio is based on the Visual Studio 2008 Shell runtime (royalty free) and can be installed without requiring any version of Visual Studio. It is hosted on codeplex. Installer, source and screencast are available from the download page. The sources require Visual Studio 2008 (Team Edition apparently) and the SDK. NOTE: Some users (myself included) had trouble getting this working. The magic steps are:
    • Download and install the Visual Studio X redistributable from: Visual Studio Extensibility
    • After you run the Install for the MS VS 2008 Shell Isolated Mode Redistributable, you must then go to the folder (« C:\VS 2008 Shell Redist\Isolated Mode« ) and click on: « vsshellisolated_enu.exe » to actually install the redistributable runtime.
    • Install IronPython Studio. Thanks to Tom Clark for the instructions. »)

Posted in Acces aux données, AJAX, Développement logiciel, multi-core, python, REST, RIA | Tagué: , , , , , , , , , , | Leave a Comment »

Développement système du noyau et des pilotes GNU/Linux

Posted by patrick sur décembre 11, 2007

Pour le développement système sous GNU/Linux la référence pour moi reste le livre de Pierre Ficheux « Linux Embarqué ». Il a écrit un certain nombre d’articles dans GNU/Linux magazine concernant le développement système sous GNU/Linux. Attention cependant: certains articles sont relativement anciens et méritent d’être largement réactualisés. Ils peuvent néanmoins servir de base pour une introduction et sont intéressants à titre historique.

  • Création d’un serveur PPP sous LINUX (« Septembre 1998. Cet article décrit la mise en place d’un serveur PPP sous LINUX. Ce serveur pourra être accessible depuis n’importe quel système équipé d’un modem et d’un logiciel d’accès à un réseau distant supportant le protocole PPP. Ceci permettra par exemple de créer simplement un BBS (Bulletin Board System) accessible depuis un navigateur standard. Ce type d’accès est très interessant pour donner la possibilité à des utilisateur éloignés d’accèder à un Intranet d’entreprise« )
  • Présentation du protocole UUCP(« Cet article présente l’utilisation et la configuration du protocole UUCP (Unix to Unix CoPy) sur LINUX. UUCP permet de manière très efficace de transférer des fichiers, du courrier électronique ou bien des news.« )
  • Ports séries sous LINUX (« Le but de cet article est la compréhension du fonctionnement des ports séries sous LINUX. L’article abordera également la configuration des ports séries depuis le shell sh ainsi qu’en langage C.« )
  • Multi-threading sous LINUX (« article d’avril 1999 à mettre à jour bien sûr: Cet article est une introduction à la programmation multi-threads sous LINUX. Les exemples de programmation utilisent la bibliothèque LinuxThreads disponible en standard sur la majorité des distributions LINUX…« )
  • Un systeme de transmission vidéo sur TCP/IP(« décembre 1998. Cet article décrit un système de transmission vidéo sur TCP/IP développé sous LINUX à partir d’un boiter de compression vidéo autonome appelé ViewCOM et développé par la société COM One à Bordeaux« )
  • Pilotes de périphériques sous LINUX (« mars 2000 : Cet article est une initiation à l’écriture de pilotes de périphériques (device drivers) sous LINUX. Les concepts généraux présentés dans l’article sont illustrés d’un petit exemple de pilote en mode caractère (char driver). La lecture de l’article demande quelques connaissances en langage C.« )
  • Programmation audio sous LINUX (« janvier 2000: Cet article est une introduction à la réalisation d’applications audios sous LINUX. Nous présenterons successivement la configuration du noyau LINUX pour le support audio, l’utilisation des fichiers spéciaux (devices) utilisés par le noyau et une introduction à la programmation en C de l’API audio de LINUX. Dans une dernière partie, nous présenterons un petit exemple d’application réalisant du streaming audio« )
  • Construction d’un système LINUX embarqué (« septembre 2000 : Le but de cet article est de présenter les différentes étapes de la réalisation d’un système LINUX embarqué (embeddable LINUX). L’article détaille les différents éléments majeurs du système ainsi que les étape de la réduction de l’occupation mémoire et disque. Nous aborderons également quelques techniques pratiques propres à la réalisation de systèmes embarqués. L’article s’appuie sur une réalisation personnelle de l’auteur. Il ne s’agit pas de la présentation de la revue d’un système embarqué de plus mais plutot d’une démarche pédagogique« )
  • Pilotes de périphériques PCI (« juin 2002: Cet article est un introduction à la gestion du bus PCI sous LINUX ainsi qu’à l’écriture de pilotes dédiés aux cartes PCI. C’est également une suite et une mise à jour de l’article Introduction à l’écriture de pilotes de périphériques LINUX paru en mai 2000 dans ce même journal. Même si certains concepts généraux liés aux pilotes et aux modules du noyau sont rappelés dans cet article, sa compréhension nécessite quelques connaissances préalables ou bien la lecture de documents cités dans la bibliographie en fin d’article« )
  • Temps réel sous LINUX (mai 2003, « Cet article a pour but de réaliser un tour d’horizon des solutions temps réel dans l’environnement LINUX. Après une définition du concept de système temps réel, les auteurs
    s’attacheront à décrire les solutions logicielles disponibles ainsi que quelques exemples de résultats obtenus…
    « )
  • Embarquez Linux! (ou Linux everywhere) (septembre 2004, « Le but de cet article est de décrire quelques techniques utilisables pour embarquer une distribution Linux réduite sur divers supports de faible capacité (CompactFlash, Disk On Module ou DoM, clé USB, Disk On Chip ou DoC). Après avoir présenté les différents supports étudiés, nous détaillerons
    une structure de système permettant de garantir une sécurité maximale de l’installation tout en minimisant l’empreinte mémoire
    . »)
  • Programmation de l’API Video4Linux (mars 2005, « Cet article décrit l’interface de programmation Video for Linux (plus communément appelée V4L) destinée à l’utilisation de périphériques de capture vidéo comme les cartes d’acquisition ou les caméras. Outre l’utilisation des pilotes existants, l’article décrit également les bases de l’écriture d’un
    pilote de périphériques V4L (caméra virtuelle) dans le cas des noyaux 2.4 et 2.6.
    ..Le problème du pilotage des périphériques vidéos est assez complexe car il existe une multitude de possibilités tant au niveau du type de périphérique (caméra, carte d’acquisition), des caractéristiques
    de ces périphériques (couleur ou noir et blanc, taille d’image, résolution) de l’architecture matérielle (type de circuit d’acquisition utilisé) ou des modes de connexion (bus PCI, USB, parallèle). Pour simplifier les choses, les développeurs du noyau Linux ont défini une interface appelée Video for Linux (Video4Linux ou V4L
    ). »)
  • Compilation croisée sous Linux et Windows (mars 2005, « Cet article décrit la mis en place d’une chaîne de compilation croisée utilisable dans l’environnement Linux x86 ou bien Windows 2000 et XP. Au cours de ce document nous décrirons des tests réels sur une cible Linux ARM mais les concepts décrits restent valable pour une autre architecture type
    PowerPC ou MIPS.
    ..Dans la série d’articles consacrés aux aspects industriels et embarqués de Linux publiés précédemment, nous avons toujours utilisé un environnement Linux x86. Même si cet environnement est très répandu, il est loin d’être le seul utilisé dans ce type d’application. En effet, d’autres processeurs comme l’ARM ou le PowerPC sont parfois mieux adaptés que l’architecture x86.
    Cependant, la plupart des développeurs utiliseront un PC x86 (Linux ou Windows) comme poste de travail et il est donc nécessaire de mettre en place un chaîne de développement croisée permettant de développer du code non-x86 sur un PC. Dans cet article, nous allons décrire plusieurs solutions open sources disponibles utilisables sur Linux x86. Ne expliquerons également comment mettre en oeuvre certains de ces outils sur plate-forme Windows en utilisant l’environnement d’émulation
    CYGWIN. A titre d’exemple, nous mettrons en place et testerons une chaîne de développement pour cible Linux ARM.
    « )
  • Quelles solutions pour Linux embarqué (décembre 2005, « Le but de cet article est de replacer Linux dans le contexte des systèmes industriels et embarqués. Le précédent article « Introduction aux systèmes embarqués » a permis de définir la terminologie et le champ d’application de cette technologie. De notre côté, nous nous attacherons à expliquer
    brièvement quels sont les avantages de Linux dans cet environnement ainsi que les composants logiciels disponibles (compilateurs, débogueurs, extensions temps-réel, etc.) Nous effectuerons également un tour d’horizon des autres solutions disponibles tout en positionnant
    Linux parmi cette liste et ce en s’aidant de quelques données statistiques. Les références à différents articles, site web ou ouvrages traitant plus précisément des sujets cités sont données en bibliographie.
    La qualification de logiciels libre nécessite de satisfaire à un certain nombre de critères. La liste complète est disponible auprès du site http://www.opensource.org mais nous pouvons retenir trois critères fondamentaux pour le logiciel embarqué:
    • La disponibilité du code source
    • La possibilité de réaliser des travaux dérivés
    • La redistribution sans royalties
    La disponibilité du code source est un critère fondamental car contrairement au logiciel classique (comme le logiciel bureautique), la durée de vie d’un logiciel embarqué est particulièrement longue
    car elle est liée à la durée de vie de l’équipement matériel qui l’héberge. Des contraintes économiques et légales font que certain
    s biens de consommation doivent être maintenus au moins 10 ans. Cette durée est parfois beaucoup plus longue dans le cas de matériel militaire ou
    scientifique. De ce fait il sera nécessaire de faire évoluer ce logiciel sur un matériel considéré comme obsolète et ce indépendamment des aléas économiques comme par exemple la disparition d’un éditeur de logiciel. Certaines licences associés aux logiciels libres (comme la GPL ou la LGPL) imposent la disponibilité du code source « ad vitam aeternam » et ce dernier ne pourra donc être séquestré même pour de sombres raisons légales ou financières.
    La réalisation de travaux dérivés est un avantage compétitif certain. Il paraît absurde de nos jours de développer une bibliothèque de traitement JPEG ou XML. Ce n’était pas forcément le cas il y a encore quelques années, ou bon nombre de petites entreprises , par ignorance ou par obstination, se lançaient dans de coûteux développements sans considérer l’existant déjà disponible à l’époque au travers du logiciel libre (je parle malheureusement en connaissance de cause !). Le problème des

    licences est à considérer avec soin dans le cas du travail dérivé mais cela n’a rien d’insurmontable et des règles simples découlant du bon sens suffisent largement au respect de licences comme la GPL ou la LGPL. La redistribution sans royalties est un atout économique évident dans le cas de la diffusion en masse d’un équipement. Avec le critère de disponibilité du code source (lui-même inspiré par des contraintes économiques) c’est certainement un des principaux arguments motivant l’adoption des logiciels libres en remplacement de solutions propriétaires. »)
  • Busybox « in a nutshell » (novembre 2005, PDF. « Cet article décrit la mise en place rapide d’un système Linux embarqué autour
    d’un noyau 2.6 et du composant libre Busybox (http://www.busybox.net ). Il fait suite aux diverses publications de l’auteur sur ce sujet dont les références sont citées en annexe bibliographique. L’article décrira l’exemple d’un PC x86 mais les concepts sont bien entendu adaptables à d’autres architectures. Le projet buildroot utilisant BusyBox et uClibc sera brièvement présenté en fin d’article sous forme d’un exemple sur architecture ARM9.
    « )
  • Temps réel sous Linux (reloaded) (mars 2006, PDF. Cet article est une mise à jour du dossier Temps réel sous Linux paru en juillet 2003
    dans le numéro 52 de Linux Magazine. Après une définition des concepts liés au temps réel, nous nous attacherons à décrire les solutions Linux disponibles en insistant particulièrement sur le composant XENOMAI 2. La lecture et la mise en application des exemples décrits nécessite une
    bonne connaissance « système » de Linux en particulier sur la compilation du noyau. Les codes source des programmes présentés sont disponibles sur http://pficheux.free.fr/articles/lmf/hs24/realtime/hs24_test.tgz
    )
  • Routeur Wifi sous Linux (mars 2006, PDF. « Cet article décrit la mise en oeuvre d’un routeur WIFI sous Linux et utilisant une architecture
    compatible x86 (VIA C3). Le projet fut démarré en 2003 ce qui explique les choix techniques qui peuvent aujourd’hui paraître quelque peu désuets (noyau 2.4.20, pas de Busybox, etc.). Il est bien évident qu’une architecture plus récente conduirait au même résultat sans pour cela changer réellement la démonstration. Le projet est totalement viable puisque qu’il a conduit à un système utilisé dans un environnement domestique 24h/24H depuis 3 ans sans aucun redémarrage, mise à part les coupures de courant ou quelques évolutions du logiciel »
    )

A voir:

Des articles plus généraux:

  • http://fr.wikipedia.org/wiki/Syst%C3%A8me_temps_r%C3%A9el (« En informatique industrielle, on parle d’un système temps réel lorsque ce système informatique contrôle (ou pilote) un procédé physique à une vitesse adaptée à l’évolution du procédé contrôlé….Les systèmes informatiques temps réel se différencient des autres systèmes informatiques par la prise en compte de contraintes temporelles dont le respect est aussi important que l’exactitude du résultat, autrement dit le système ne doit pas simplement délivrer des résultats exacts, il doit les délivrer dans des délais imposés…« )
  • http://systeme.developpez.com/cours/#C3 (« des cours sur l’architecture, les systèmes embarqués, les systèmes temps réels, les systèmes d’exploitation, les systèmes répartis, les réseaux, le parallèlisme et les grilles de calcul, la sécurité, la compression audi et vidéo, les annuaires LDAP »)

Posted in Développement logiciel, GNU/Linux | Tagué: , | Leave a Comment »