Agility by example

I’ve found this article today thanks to alex(Agilex), Team practices,

(in french…sorry) but that’s definitely one of the best example of agility in practice !

a MUST READ !

Virtualisation

Virtualisation is a technique to emulate/simulate a set of servers on a physical box. Virtualisation can be seen as a easy way to have a pool of available server to ease to scale application deployment, to ease deployment or recovery procedure.

But … when you developp is can be use to enhance your application quality, and that’s often forgot.

Imagine 5s, than you can now :

• have a blank server in 5 minutes to build hourly your sever, avoiding side effect of previous installation
• have a server with previous release install to validate deployment procedure
• have a network and a farm of sever that are software … not hardware, and now you can simulate/emulate network outage, network slowdown, server crash not by removing the electric plug, but by sending a shell command, …
• imagine you can crash your server and can restart a new instance of it without waiting somebody switch on your box, …
• imagine you can test load balancing/concurrency with only one physical box …..

Do you start to see the fantastic power of virtualisation to validate your application ?

Continuous Integration Step by Step

My current hobby, as said in a previous post is CI. I strongly beleive that having a CI in place for your development speed up, and secure your development process. SO, in order to convince or to help you to set up such framework, i’ll try to summarize and give the key point of such framework.

My current feeling, is that a CI framework is mainly maid of 3 major block, with 2 optionnal small one. We can wrote a book on the small one, but regarding to the big CI bloc, they are small in this context .

This 3 blocks for me are :

1. Source code repository : this is the entry point of the whole story, the place where all the developper commit their code, the source from your application releases are build, the central point to get the history of your code writting skill history. In this family the most well known source code repository tools are : CVS / Subversion / Perforce …..
2. The build tool, often forgotten, allow you to transform you source code into a deployable library or an application. I emphasis this point, as often it is consider as a minor element of the CI, but i strongly believe that’s the hart. Indeed, well used, it’s allow you to build easily library, handle dependency among your library, allow you to easily standardize programming rules or tools to run among your libraries.  The most common are Ant/Maven/Make/phing/…. At this point i will rise a little warning. In large/medium size company, your application is made of several block, some of them can use several programming language  (SQL for your DB, Java/C/C++ for the backend/middle tiers, PHP/JavaScript for the front end, perl/sh for the scripting part, ….). So a big choice will be either to use the same tools for all the application block, or use a more specialized one for dedicated part. The choice is not easy to do, but one of the argument will be the IDE used by the human to wrote their code, and the integration of the build tool with this IDE.
3. The CI tool. For me this tools should only ensure the synchrnosition between the source repository and the build tools. Each time something change, at fix hour, when a tag is set on the code it should launch a build of the whole application. It should keep also an history of all the build, and the documentation/metrics produce by the build process (hudson, continuum, cruise control, …).
4. Now, the two optionnal part, ecause they are nice to have, but not mandatory to succeed in CI. The IDE, which is the entry point of the code. I will say that’s an optional part, as you can do CI without it, but i think to strongly benefit of the CI, of the instrumented build tool, the standardization of the DEV, a good IDE with some instrumentisation is a huge benefit (Eclipse, netbeans, ..) .
5. Deployment and configuration management tools : definitively forgotten in most of the framework, the deployment and the configuration of your application is a key issue. You application is not only WebService or an simple programme. It’s composed of a bunch of library jar, so, rpm, a bunch of application (scripts, cron, monitoring, admin, ….), and requier a set of configuration to allow each part of your application to interact together, or to configure your OS.  In a perfect world, the same tools is used in CI, QA, and production in order to validate deployment and automate it, as soon as possible.

You may found some interesting presentation : here for php, or …

An other fan

Immediate benefice of opening a blog, I’ve discovered the blog of vikashazrati, because he use the same tag than me
So, after a quick overview, it seems very interesting, i should spend some time reading it.

Yahoo pipes

I don’t like reading blogs !!!! (that’s why i’m writing one ), what annoy me is : i know too many people having one, and i can’t follow them on a regular basis. So what i need is :

either an efficient search tools to look for topic interesting me, only on this subset of blog

or and efficient way of filtering them.

I’ve start trying the second approach, and I’ve play with yahoo pipes. Easy to set up, and it did nearly what i want. I was also able to customize the output to fit my purpose.

you can see an example at :

http://pipes.yahoo.com/pipes/pipe.info?_id=GnmsRQRC3RGBb3BeMlrX_Q

Ouel

Static code analysis

My current hobby is to find efficient / easy to use / and well package tools to analyse code.

For those of you who don’t know these technics,  I’ll summarize them as : ‘tools which analyse your source code, in order to help you to find potentiel bugs, or it try to convince you to change your way of programming and may give you some new programming hits, ….,’.

If your build process is clean, or if you use a standard IDE, adding these tools is very cheap, and the benefice is great.

One more ….

Some of my friends start again their blog,  i was thinking, why not …..

So, taking two minutes of my time, looks for a blog site … and create my own.