This guide assumes you have successfully installed Flask-Registry and a working understanding of Flask. If not, follow the installation steps and read about Flask at http://flask.pocoo.org/docs/.

A Minimal Example

A minimal Flask-Registry usage example looks like this. First create the application and initialize the extension:

>>> from flask import Flask
>>> from flask_registry import Registry
>>> from flask_registry import ListRegistry
>>> app = Flask('myapp')
>>> r = Registry(app=app)

Then, we can create a simple ListRegistry that just keeps a list of objects:

>>> r['my_namespace'] = ListRegistry()
>>> r['my_namespace'].register("something")
>>> r['my_namespace'].register("something else")
>>> for obj in r['my_namespace']:
...     print(obj)
something else

Application Discovery Example

Flask-Registry also has support for dynamically discovering Python modules, resources, entry points and the like. All this can be put together in your Flask application factory to create and easily extensible application.

Following is a small example how a Flask application can be assemble from reusable packages that each provides configuration, extensions and blueprints:

from flask import Flask

from flask_registry import (BlueprintAutoDiscoveryRegistry,
                            ConfigurationRegistry, ExtensionRegistry,
                            PackageRegistry, Registry)

class Config(object):
    PACKAGES = ['registry_module']
    EXTENSIONS = ['registry_module.mockext']
    USER_CFG = True

def create_app(config):
    app = Flask('myapp')
    r = Registry(app=app)
    r['packages'] = PackageRegistry(app)
    r['extensions'] = ExtensionRegistry(app)
    r['config'] = ConfigurationRegistry(app)
    r['blueprints'] = BlueprintAutoDiscoveryRegistry(app=app)
    return app

if __name__ == '__main__':
    config = Config()
    app = create_app(config)

Save this in a file named app.py next to the tests folder in the Flask-Registry distribution and run it using your Python interpreter.

$ python app.py
 * Running on
$ curl http://localhost:5000
Hello from Flask-Registry

The blueprint is loaded from tests.views and only works if the extension registry_module.mockext and the configuration in registry_module.config has been loaded.

See Application Discovery for full explanation on what is happening in the example.