Fabric and Django deployment scenario

Question

My deployment scenario involves a typical Django setup, but runs on multiple servers. Basically, I upload the source code, perform several build steps (compile .pyc files, collectstatic, etc.), then rung syncdb and migrate , finally reload apache2.

My problem is that I deploy the code to 4-5 servers with more planned in the future and the deploy takes a long time (more than a minute per server). Almost all the steps in the deploy process can be done in parallel, except syncdb/migrate. Is there a way using Fabric to only run those on one of the machines (the DB server is separate from the rest), and run the rest of the tasks in parallel?

Answer 1

Have you tried create a function for each task and another task to call them all?

Example:

@task
@parallel
copy_files():
    run('cp *')
    ...

@task
@parallel
restart_apache():
    run('/etc/init.d/httpd restart')
    ...

@task
syncdb_app():
    run('python manage.py syncdb')
    ...

@task
deploy():
    copy_files()
    restart_apache()
    syncdb_app()
    ...