Application_Python Cookbook

A Chef cookbook to deploy Python applications.

Quick Start

To deploy a Django application from git:

application '/srv/myapp' do
  git 'https://github.com/example/myapp.git'
  virtualenv
  pip_requirements
  django do
    database 'sqlite:///test_django.db'
    secret_key 'd78fe08df56c9'
    migrate true
  end
  gunicorn do
    port 8000
  end
end

Requirements

Chef 12 or newer is required.

Resources

application_celery_beat

The application_celery_beat resource creates a service for the celery beat
process.

application '/srv/myapp' do
  celery_beat do
    app_module 'myapp.tasks'
  end
end

Actions

• :enable – Create, enable and start the service. (default)
• :disable – Stop, disable, and destroy the service.
• :start – Start the service.
• :stop – Stop the service.
• :restart – Stop and then start the service.
• :reload – Send the configured reload signal to the service.

Properties

• path – Base path for the application. (name attribute)
• app_module – Celery application module. (default: auto-detect)
• service_name – Name of the service to create. (default: auto-detect) # user – User to run the service as. (default: application owner)

application_celery_config

The application_celery_config creates a celeryconfig.py configuration file.

application '/srv/myapp' do
  celery_config do
    options do
      broker_url 'amqp://'
    end
  end
end

Actions

• :deploy – Create the configuration file. (default)

Properties

• path – Path to write the configuration file to. If given as a directory, create path/celeryconfig.py. (name attribute)
• options – Hash or block of options to set in the configuration file.

application_celery_worker

The application_celery_worker resource creates a service for the
celery worker process.

application '/srv/myapp' do
  celery_worker do
    app_module 'myapp.tasks'
  end
end

Actions

• :enable – Create, enable and start the service. (default)
• :disable – Stop, disable, and destroy the service.
• :start – Start the service.
• :stop – Stop the service.
• :restart – Stop and then start the service.
• :reload – Send the configured reload signal to the service.

Properties

• path – Base path for the application. (name attribute)
• app_module – Celery application module. (default: auto-detect)
• service_name – Name of the service to create. (default: auto-detect) # user – User to run the service as. (default: application owner)

application_django

The application_django resource creates configuration files and runs commands
for a Django application deployment.

application '/srv/myapp' do
  django do
    database 'sqlite:///test_django.db'
    migrate true
  end
end

Actions

• :deploy – Create config files and run required deployments steps. (default)

Properties

• path – Base path for the application. (name attribute)
• allowed_hosts – Value for ALLOWED_HOSTS in the Django settings. (default: [])
• collectstatic – Run manage.py collectstatic during deployment. (default: true)
• database – Database settings for the default connection. See the database section below for more information. (option collector)
• debug – Enable debug mode for Django. (default: false)
• local_settings – A Poise template property for the content of the local settings configuration file.
• local_settings_path – Path to write local settings to. If given as a relative path, will be expanded against path. Set to false to disable writing local settings. (default: local_settings.py next to settings_module)
• migrate – Run manage.py migrate during deployment. (default: false)
• manage_path – Path to manage.py. (default: auto-detect)
• secret_key – Value for SECRET_KEY in the Django settings. If unset, no key is added to the local settings.
• settings_module – Django settings module in dotted notation. (default: auto-detect)
• syncdb – Run manage.py syncdb during deployment. (default: false)
• wsgi_module – WSGI application module in dotted notation. (default: auto-detect)

Database Parameters

The database parameters can be set in three ways: URL, hash, and block.

If you have a single URL for the parameters, you can pass it directly to
database:

django do
  database 'postgres://myuser@dbhost/myapp'
end

Passing a single URL will also set the $DATABASE_URL environment variable
automatically for compatibility with Heroku-based applications.

As with other option collector resources, you can pass individual settings as
either a hash or block:

django do
  database do
    engine 'postgres'
    user 'myuser'
    host 'dbhost'
    name 'myapp'
  end
end

django do
  database({
    engine: 'postgres',
    user: 'myuser',
    host: 'dbhost',
    name: 'myapp',
  })
end

application_gunicorn

The application_gunicorn resource creates a service for the
Gunicorn application server.

application '/srv/myapp' do
  gunicorn do
    port 8000
    preload_app true
  end
end

Actions

• :enable – Create, enable and start the service. (default)
• :disable – Stop, disable, and destroy the service.
• :start – Start the service.
• :stop – Stop the service.
• :restart – Stop and then start the service.
• :reload – Send the configured reload signal to the service.

Properties

• path – Base path for the application. (name attribute)
• app_module – WSGI module to run as an application. (default: auto-detect)
• bind – One or more addresses/ports to bind to.
• config – Path to a Guncorn configuration file.
• preload_app – Enable code preloading. (default: false)
• port – Port to listen on. Alias for bind("0.0.0.0:#{port}").
• service_name – Name of the service to create. (default: auto-detect) # user – User to run the service as. (default: application owner)
• version – Version of Gunicorn to install. If set to true, use the latest version. If set to false, do not install Gunicorn. (default: true)

application_pip_requirements

The application_pip_requirements resource installs Python packages based on a
requirements.txt file.

application '/srv/myapp' do
  pip_requirements
end

All actions and properties are the same as the pip_requirements resource.

application_python

The application_python resource installs a Python runtime for the deployment.

application '/srv/myapp' do
  python '2.7'
end

All actions and properties are the same as the python_runtime resource.

application_python_execute

The application_python_execute resource runs Python commands for the deployment.

application '/srv/myapp' do
  python_execute 'setup.py install'
end

All actions and properties are the same as the python_execute resource,
except that the cwd, environment, group, and user properties default to
the application-level data if not specified.

application_python_package

The application_python_package resource installs Python packages for the deployment.

application '/srv/myapp' do
  python_package 'requests'
end

All actions and properties are the same as the python_package resource,
except that the group and user properties default to the application-level
data if not specified.

application_virtualenv

The application_virtualenv resource creates a Python virtualenv for the
deployment.

application '/srv/myapp' do
  virtualenv
end

If no path property is given, the default is to create a .env/ inside the
application deployment path.

All actions and properties are the same as the python_virtualenv resource.

Examples

Some test recipes are available as examples for common application frameworks:

• Flask
• Django

Sponsors

Development sponsored by Chef Software, Symonds & Son, and Orion.

The Poise test server infrastructure is sponsored by Rackspace.

License

Copyright 2015, Noah Kantrowitz

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.