A VM4C3PO
We have just set up a vagrant environment for C3PO. It starts a headless vm where the C3PO related functionalities (Mongodb, Play, a downloadable commandline jar) are managable from the host's browser. Further, the vm itself has all relevant processes configured at start-up independently from vagrant, so it can be, once created, downloaded and used as a stand-alone C3PO vm. We think this could be a scenario applicable to other SCAPE projects as well. The following is a summary of the ideas we've had and the experiences we've made.
The Result
The Vagrantfile and a directory containing all vagrant-relevant files live directly in the root directory of the C3PO repository. So after installing Vagrant and cloning the repository a simple 'vagrant up' should do all the work, as downloading the base box, installing the necessary software and booting the new vm.
After a few minutes one should have a running vm that is accessible from the hosts browser at localhost:8000. This opens a central welcome page that contains information about the vm-specific aspects and links to the playframework's url (localhost:9000) and the Mongodb admin interface (localhost:28017). It also provides a download link for the command-line jar, which has to be used in order to import data. This can be used from the outside of the vm as the Mongodb port is mapped as well. So I can import and analyse data with C3PO without having to fiddle through the setup challenges myself, and, believe me, that way can be long and stony.
The created image is self-contained in that sense that, if I put it on a server, anyone who has Virtualbox installed can download it and use it, without having to rely on vagrant working on their machine.
General Setup
The provisioning script has a number of tasks:
- it downloads all required dependencies for building the C3PO environment
- it installs a fresh C3PO (from /vagrant, which is the shared folder connection between the git repository and the vm) and assembles the command-line app
- it installs and runs a Mongodb server
- it installs and runs the Playframework
- it creates a port-forwarded static welcome page with links to all the functionalities above
- it adds all above to the native ubuntu startup (using /etc/rc.local, if necessary), so that an image of the vm can theoretically be run independently from the vagrant environment
These are all trivial steps, but it can make a difference not having to manually implement all of them.
Getting rid of proxy issues
In case you're behind one of those very common NTLM company proxies, you'll really like that the only thing you have to provide is a config script with some some details around your proxy. If the setup script detects this file, it will download the necessary software and configure maven to use it. Doing it in this way has been actually the first time I got maven running smoothly on a linux VM behind our proxy.
Ideas for possible next steps
There is loads left to do, here are a few ideas:
- provide interesting initial test-data that ships with the box, so that people can play around with C3PO without having to install/import anything at all.
- why not having a vm for more SCAPE projects? we could quickly create a repository for something like a SCAPE base vm configuration that is useable as a base for other vms. The central welcome page could be pre-configured (SCAPE branded) as well as all the proxy- and development-environment-related stuff mentioned above.
- I'm not sure about the sustainablity of shell provisioning scripts with increasing complexity of the bootstrap process. Grouping the shell commands in functions is certainly an improvement, it might be worth though to check out other, more dynamic provisioners. One I find particularly interesting is Ansible.
- currently there's no way of testing that the vm works with the current development trunk; a test environment that runs the vm and tests for all the relevant connection bits would be handy
