converge 0.7

1 What is it?

If you are a Python developer who likes to keep application configuration in simple Python modules and that your app have some default settings and production/dev/test setting files, converge can help you merge settings and load desired application settings.

2 Getting started

default_settings.py
-------------------
SERVER_PORT = 8000
DOMAIN = 'example.com'
ADMIN_EMAIL = 'admin@example.com'

dev_settings.py
---------------
SERVER_PORT = 9000

from converge import settings
print(settings.SERVER_PORT)  # 9000
print(settings.DOMAIN)  # example.com
print(settings.get('VAR_THAT_DOESNT_EXIST'))  # None

pip install converge

3 .convergerc

.convergerc file helps converge choose application mode and in turn load correct settings file.

.convergerc
-----------

APP_MODE = 'test'
SETTINGS_DIR = 'appsettings'

4 Supported settings files

• Defaults: default_settings.py

• Mode

  • production: prod_settings.py

  • development: dev_settings.py

  • test: test_settings.py

  • staging: staging_settings.py

• Deployment specific: site_settings.py

5 Guidelines

Settings files are usual Python files that can contain valid python code however here are some guidelines for user

• Use module variables for global application wide configuration

• Use UPPERCASE while naming settings variables

• For values prefer basic python datatypes usch as string, integer, tuples

• eg. SERVER_PORT = 1234

• Avoid complex python operations

• Use simple classes for config sections

  class DB:
      HOST = 'db.example.com'
      PORT = 1234

• Use simple string operations to avoid repeatation

  BASE_DOMAIN = 'example.com'
  API_URL = 'api.' + BASE_DOMAIN``

6 Overriding settings

Defining module veriables in site_settings.py

7 Overriding partial settings

Example:

default_settings.py

class DB:
    HOST = 'db.example.com'
    PORT = 1234

site_settings.py

DB.PORT = 1111

8 (Slightly) Advanced usage

In case if you want to keep all settings.py files in a directory. Use SETTINGS_DIR directive in .convergerc file.

>> cat .convergerc

APP_MODE = 'prod'
SETTINGS_DIR = 'settings/fat_server'

`-- settings/
     |
     |-- server1/
     |      |
     |      |--default_settings.py
     |      |--prod_settings.py
     |
     |-- server2/
     |      |--default_settings.py
     |      |--prod_settings.py
     |
     |

9 For Contributors

Running tests

git clone <repo>
cd converge
nosetests -xv tests.py