fabutils

Utilities for creating better fabric tasks.

Install

$ pip install vo-fabutils

Usage

Import the proper fabutils modules inside your fabfile an hack a nice day.

Examples

Define environments in JSON format

First you must create a JSON file containing your environment configuration.

# /path/to/environments/file.json
{
    "devel": {
        "user": "devel-user",
        "hosts": ["dev.host.com"],
        "site_dir": "/path/to/devel/site/www/",
        "command_prefixes": [
            "/path/to/devel/site/env/bin/activate"
        ]
    },
    "production": {
        "user": "prod-user",
        "hosts": ["host.com"],
        "site_dir": "/path/to/production/site/www/",
        "command_prefixes": [
            "/path/to/production/site/env/bin/activate"
        ]
    }
}

Note that:

• You can define any arbitrary string as env properties and these will be passed to the task's env.
• Properties with names "reserved" by fabric will be recognized by it and treated with the special meanig that fabric has for them.
• The only caveat is that if you define an array of command_prefixes you must only list the path to the script and this will be automatically prepended to with the word 'souce'. For example if you define ../some_script in your command_prefixes, it will be tranformed to source ../some_script.
• Every directory path must end with a trailing slash.

Next, import fabutils.env.set_env in your fabfile and create a task that calls it with the path to your JSON file.

# fabfile.py
from fabric.api import task
from fabutils.env import set_env


@task
def environment(env_name):
    set_env(env_name, '/path/to/environments/file.json')

Now you can run tasks in the environment by calling environment:name before your task.

# Run a task in devel environment
$ fab environment:devel some_task

# Run a task in production environment
$ fab environment:production some_task

Arbitrary options and parameters

Some times you just need to pass an unknown number of options/arguments to a command, in this case you can use join, options and arguments utils to translete the pythonic *args to command arguments and **kwargs to command options.

from fabric.api import task, run
from fabutils import join, arguments, options


@task
def some_task(*args, **kwargs):
    run(join('some_command', arguments(*args, **kwargs))

And then call your task using the fabric's notation

$ fab some_task:arg1,arg2,kwarg1=val1,kwarg2=val2

# The above will be translated to:
# some_command arg1 arg2 kwarg1=val1 kwarg2=val2

If you pass your *kwargs to options the keys that are evaluated to a boolean True will be translated to --{key} notation.

...

@task
def another_task(**kwargs):
    return(join('another_command', options(**kwargs)))

...

$ fab another_task:option1=True,option2=No,option3=1,option4=False

# The above will be translated to:
# another_command --option1 --option3

Of course, you can combine the two approaches.

...
from fabutils import boolean

@task
def the_task(*args, **kwargs):
    options = {}
    arguments = {}
    
    for k, v in kwargs:
        if boolean(v):
            options[k] = v

        else:
            arguments[k] = v

    run(join('the_command', arguments(*args, **arguments), options(**options)))

...

$ fab the_task:arg1,arg2=val2,option1=True

# The above will be translated to:
# the_command arg1 arg2=val2 --option1