[Engine-devel] [ANN] New development environment for ovirt-engine

[Alon Bar-Lev]

Hello all ovirt-engine developers,

When I first joined the ovirt project, it took me about two weeks to setup a development environment, I needed to work on a bug related to host-deploy so I needed an environment that could use the ssh, PKI, vdsm-bootstrap and communicate with vdsm using SSL, this was virtually impossible to do so without tweaking the product in a way that it is so different from production use, that I cannot guarantee that whatever tested in development will actually work in production.

I peeked at the installation script in a hope that I can create partial environment similar to production, but I found that the packaging implementation makes to much assumption and is very difficult to adopt. The fact that I do not use fedora/rhel for my development made it even worse.

I had no other option than to create rpms after each of my changes and test each in real production like setup.

It was obvious to me that the manual customization of developers to achieve working product will eventually break as product grow and move away from being developer friendly to production friendly. For example, product defaults cannot be these which serve developers, but these which serve production the best, or having a valid PKI setup cannot be optional any more as components do need to use it. Same for location of files and configuration, for example, if we write a pluggable infrastructure for branding, we cannot damage the interface just because developers runs the product in their own manual customization.

I took the opportunity handed to me to port the ovirt-engine to other distributions in order to provide a development environment that is similar to production setup. Together with Sandro Bonazzola and Alex Lourie we re-wrote the whole installation of the product which can also be used to setup the desired development environment.

Within this environment the product is set up using the same tools and configuration as in production, while the process does not require special privileges nor changes the state of the developer machine. 

A complete documentation is available[1], I preferred to use README within the source tree as wiki tend to quickly become obsolete, while documentation within source tree can be modified by the commit that introduces a change. I will redirect to this file from the current wiki once the site will be up.

In a nut shell, after installing prerequisites, build and install the product using:

$ make clean install-dev PREFIX=$HOME/ovirt-engine

This will run maven and create product installation at $HOME/ovirt-engine
Next, a setup phase is required just like in production, to initialize configuration and database:

$ $HOME/ovirt-engine/bin/engine-setup-2

You have now fully functional product, including PKI, SSL, host-deploy, tools.
No manual database updates are required, no lose of functionality.

All that is left is to start the engine service:

$ $HOME/ovirt-engine/share/ovirt-engine/services/ovirt-engine.py start

Access to application:
   http://localhost:8080
   https://localhost:8443
Debugging port is opened at port 8787.

Farther information exists in the documentation[1].

There are several inherit benefits of the new environment, the major one is the ability to manage several environments in parallel on the same host. For example, if we develop two separate features on two branches we can install the product into $HOME/ovirt-engine-feature1 and $HOME/ovirt-engine-feature-2 and have a separate database for each, if we modify the ports jboss is listening to we can run two instances of engine at the same time!

We will be happy to work with all developers to assist in porting into the new development environment, the simplest is to create a new database for this effort. Moti has a sequence of converting the existing database owned by postgres to be owned by the engine, Moti, can you please share that?

We are sure there are missing bits, we will be happy to know these so we can improve.

I am aware that developers (especially java) are conservative, but I ask you to give us a chance, so that we make it easy for developers to join the project, and to allow us to drop the parallel effort of packaging to production and fixing the broken development environment. 

A special thanks to developers who took the time to test and provide feedback before the merged:
- Yaniv Bronheim
- Moti Asayag
- Limor Gavish
- Sharad Mishra
- Ofer Schreiber

We are hoping that after migration you will be find this environment useful and friendly,

Sandro Bonazzola,
Alex Lourie,
Alon Bar-Lev.

[1] http://gerrit.ovirt.org/gitweb?p=ovirt-engine.git;a=blob;f=README.developer;hb=HEAD