A collection of tasks for *Invoke* to set up a Django project with Gunicorn on Uberspace.

tasks.py

# -*- coding: UTF-8 -*-

"""
A collection of tasks for `Invoke`_ to help setting up a `Django`_ project
with `Gunicorn`_ on `Uberspace`_ accounts.

All information for this script has to be set in a JSON file
called ``settings.json`` in the same directory like this::

  {
    "project": "name of the project",
    "settings": {
      "stageing": {
        "host": "uberspace.host.url",
        "user": "username",
        "py_path": "path for project and apps",
        "py_files": [
          "path/to/project", "app1", "app2"
        ],
        "django_port": 63557,
        "django_url": "django.project.url",
        "django_settings": "project.settings.stageing",
        "app": "project.wsgi:application"
      }
    }
  }

More informations: https://wiki.uberspace.de/cool:django

.. _Invoke: http://docs.pyinvoke.org/en/latest/
.. _Django: https://docs.djangoproject.com/en/stable/
.. _Gunicorn: http://gunicorn.org/
.. _Uberspace: https://uberspace.de/

"""

from __future__ import absolute_import
from __future__ import unicode_literals

import json

from invoke import run, task


with open('settings.json') as fh:
  SETTINGS = json.load(fh)


def ssh_cmd(command, user, host, echo=True, pty=True):
  """
  Runs *command* trough ssh with *user* and *host*.

  """
  ssh = "ssh '{user}@{host}' '{cmd}'".format(
    user=user, host=host, cmd=command
  )
  run(ssh, echo=echo, pty=pty)


def get_service_name(project, config):
  """
  Returns the name for the gunicorn service.

  Given the current *project* and the chosen *config*.

  """
  return 'gunicorn-{project}-{config}'.format(
    project=project, config=config
  )


@task()
def copy(config='stageing'):
  """
  Copies your python files to the host.

  """
  args = SETTINGS['settings'][config]
  dest = args['py_path']
  user, host = args['user'], args['host']
  for path in args['py_files']:
    cmd = "rsync -arv --delete --exclude '*.pyc' '{src}' '{user}@{host}:{dest}'"
    cmd = cmd.format(user=user, host=host, src=path, dest=dest)
    run(cmd)


@task
def service(config='stageing'):
  """
  Creates the *gunicorn* service for ``svc``.

  """
  args = SETTINGS['settings'][config]
  user, host = args['user'], args['host']
  service_name = get_service_name(SETTINGS['project'], config)
  # check for `service` dir:
  cmd = "test -d ~/service || uberspace-setup-svscan"
  ssh_cmd(cmd, user, host)
  # install service:
  cmd = 'uberspace-setup-service {service} ~/bin/gunicorn --error-logfile - --chdir {path} --bind 127.0.0.1:{port} {app}'
  cmd = cmd.format(
    service=service_name, path=args['py_path'], port=args['django_port'], app=args['app']
  )
  cmd = "test -d ~/service/{service} || {cmd}".format(
    cmd=cmd, service=service_name
  )
  ssh_cmd(cmd, user, host)
  # set export for DJANGO_SETTINGS_MODULE:
  cmd = "sed -i 's#\(\. $HOME/\.bash_profile\)#\1\n\nexport DJANGO_SETTINGS_MODULE={settings}#' ~/service/{service}/run"
  cmd.format(
    settings=args['django_settings'], service=service_name
  )
  ssh_cmd(cmd, user, host)


@task
def rmservice(config='stageing'):
  """
  Removes the *gunicorn* service.

  """
  args = SETTINGS['settings'][config]
  service_name = get_service_name(SETTINGS['project'], config)
  cmd = "cd ~/service/{service} && rm ~/service/{service} && svc -dx . log; cd && rm -rf ~/etc/run-{service}/".format(
    service=service_name
  )
  ssh_cmd(cmd, args['user'], args['host'])


@task
def http(config='stageing'):
  """
  Creates HTTP rewrite rules for Apache.

  """
  args = SETTINGS['settings'][config]
  cmd = 'cat <<__EOF__> ~/html/{url}/.htaccess\n'.format(
    url=args['django_url']
  )
  cmd += 'RewriteEngine On\n'
  cmd += 'RewriteCond %{REQUEST_FILENAME} !-f\n'
  cmd += 'RewriteBase /\n'
  cmd += 'RewriteRule ^(.*)$ http://127.0.0.1:{port}/\$1 [P]\n'.format(
    port=args['django_port']
  )
  cmd += 'RequestHeader set X-Forwarded-Proto https env=HTTPS\n'
  cmd += '__EOF__\n'
  ssh_cmd(cmd, args['user'], args['host'])


@task
def rmhttp(config='stageing'):
  """
  Removes HTTP rewrite rules.

  """
  args = SETTINGS['settings'][config]
  cmd = 'rm ~/html/{url}/.htaccess'.format(
    url=args['django_url']
  )
  ssh_cmd(cmd, args['user'], args['host'])