MilkyWhite
=================================================================

MilkyWhite is a simple application environment designed for django. Is was developed to create an 
easy and understandable foundation for django application hosting. It setups an application/webserver 
to host the application and handles the installation/uninstallation of the application on the server.

There can be multiple servers at the same time, working independent of each other (and do not need to
know each other). Every server is part of a group and every server in a group has the same apps in the
same version, but different groups can host different apps, or the same apps in different versions 
(like stable/unstalbe).

The basic design of MilkyWhite is optimized for cloud hosters and uses amazon s3 to host the package
files and the central package index. Nothing else is shared between the servers.
An S3 storage is also used to collect the log files of the servers.

The setup of each server consists of nginx as frontend server and apache as mod_wsgi hoster.
Every package can, but doesn't need to, add own configs to these two servers.

To upload an application, switch version or upload a new version, the admin can/must use the 
controller(.py) in the MilkyWhite directory. It only changes the files on the S3 share, but do
not touch the server directly (at the moment, at least).
On the server, cron will start the server.py every 5 minutes to check for new data on S3. 
This is also done on boot time, which is important if you use an preconfigured Image to start new servers,
like it is common with auto-scale solutions.

Both server and controller need a settings.py in there own directory.

Installation
============

Install a basic Ubuntu 10.04 system, download the install_server.sh from the repository and run it.
It will setup MilkyWhite itself. It also downloads MilkyWhite form the main repository. 

If you don't want to use it that way, please do the steps inside of the install_server.sh on your own.

Usage of the Controller
=======================

How to use:
-----------
python controller.py [command] [parameter] ... [parameter] 


Upload-Command:
-------------
Uploads a new application version to a specific server group

Command:
python controller.py upload [group] [file]

Example:
python controller.py upload stable ../../build/myapp_436346436.bzip2

After the upload, the version.info is update.
Then, one server is updated first, to run one-time tasks like db migration.
After that, all servers are called to update there applications.

Version-Command:
----------------
Switch to another version of an application.

Command:
python controller.py version [group] [app] [version]

Example:
python controller.py version stable myapp v1022

The command updates the version.info file, but only if there is really that
version on the server.
After that, all servers are updated.

Remove-Command:
--------------
Removes a file from a server (but keeps the files on s3)

Command:
python controller.py remove [group] [app]

Example:
python controller.py remove stable oldappname

Info-Command:
--------------
List all groups, there apps and versions in the version.info file

Command:
python controller.py info