python-dependency-injector/examples/advanced_usage/inject_flask.py

"""`inject()` decorator and Flask view example."""

import sqlite3
import flask

import dependency_injector.providers as providers
import dependency_injector.injections as injections


database = providers.Singleton(sqlite3.connect,
                               ':memory:',
                               timeout=30,
                               detect_types=True,
                               isolation_level='EXCLUSIVE')

app = flask.Flask(__name__)


@app.route('/')
@injections.inject(database)
@injections.inject(flask.request)
def hello(request, database):
    """Example Flask view."""
    print request
    one = database.execute('SELECT 1').fetchone()[0]
    return 'Query returned {0}, db connection {1}'.format(one, database)


if __name__ == '__main__':
    app.run()

# Example output of "GET / HTTP/1.1" is:
# Query returned 1, db connection <sqlite3.Connection object at 0x1057e4030>