Quart-Motor 2.4.2

Motor support for Quart applications

Quart-Motor

MongoDB <http://www.mongodb.org/>_ is an open source database that stores flexible JSON-like "documents," which can have any number, name, or hierarchy of fields within, instead of rows of data as in a relational database. Python developers can think of MongoDB as a persistent, searchable repository of Python dictionaries (and, in fact, this is how PyMongo <http://api.mongodb.org/python/current/>_ represents MongoDB documents).

Quart-Motor bridges Quart and Motor and provides some convenience helpers.

Quickstart

First, install Quart-Motor:

$ pip install Quart-Motor

Next, add a :class:~quart_motor.Motor to your code:

    from quart import Quart
    from quart_motor import Motor

    app = Quart(__name__)
    app.config["MONGO_URI"] = "mongodb://localhost:27017/myDatabase"
    mongo = Motor(app)

:class:~quart_motor.Motor connects to the MongoDB server running on port 27017 on localhost, to the database named myDatabase. This database is exposed as the :attr:~quart_motor.Motor.db attribute.

You can use :attr:~quart_motor.Motor.db directly in views:

    @app.route("/")
    def home_page():
        online_users = mongo.db.users.find({"online": True})
        return render_template("index.html",
            online_users=online_users)

Compatibility

Quart-Motor depends on recent versions of Quart, Motor and PyMongo, where "recent" is defined to mean "was released in the last 3 years". Quart-Motor may work with older versions, but compatibility fixes for older versions will not be accepted, and future changes may break compatibility in older versions.

Quart-Motor is tested against supported versions <https://www.mongodb.com/support-policy>_ of MongoDB, 3.5+.

Quart-Motor works very well with uvicorn asgi, while with hypercorn sometimes it has multiple loop problems (motor attached to different loop).

Quart-Motor is tested against Python 3.7+ versions.

Helpers

Quart-Motor provides helpers for some common tasks:

.. automethod:: quart_motor.wrappers.Collection.find_one_or_404

.. automethod:: quart_motor.Motor.send_file

.. automethod:: quart_motor.Motor.save_file

.. autoclass:: quart_motor.helpers.BSONObjectIdConverter

.. autoclass:: quart_motor.helpers.JSONEncoder

Configuration

You can configure Quart-Motor either by passing a MongoDB URI <https://docs.mongodb.com/manual/reference/connection-string/>_ to the :class:~quart_motor.Motor constructor, or assigning it to the MONGO_URI Quart configuration variable <https://pgjones.gitlab.io/quart/how_to_guides/configuration.html>_

The :class:~quart_motor.Motor instnace also accepts these additional customization options:

• json_options, a :class:~bson.json_util.JSONOptions instance which controls the JSON serialization of MongoDB objects when used with :func:~quart.json.jsonify.

You may also pass additional keyword arguments to the Motor constructor. These are passed directly through to the underlying :class:~motor.motor_asyncio.AsyncIOMotorClient object.

Note:

By default, Quart-Motor sets the ``connect`` keyword argument to
``False``, to prevent Motor from connecting immediately. Motor
itself `is not fork-safe
<http://api.mongodb.com/python/current/faq.html#is-pymongo-fork-safe>`_,
and delaying connection until the app is actually used is necessary to
avoid issues. If you wish to change this default behavior, pass
``connect=True`` as a keyword argument to ``Motor``.

You can create multiple Motor instances, to connect to multiple databases or database servers:

    app = Quart(__name__)

    # connect to MongoDB with the defaults
    mongo1 = Motor(app, uri="mongodb://localhost:27017/databaseOne")

    # connect to another MongoDB database on the same host
    mongo2 = Motor(app, uri="mongodb://localhost:27017/databaseTwo")

    # connect to another MongoDB server altogether
    mongo3 = Motor(app, uri="mongodb://another.host:27017/databaseThree")

Each instance is independent of the others and shares no state.

API

Classes

.. autoclass:: quart_motor.Motor :members:

.. attribute:: cx

  The :class:`~quart_motor.wrappers.AsyncIOMotorClient` connected to the
  MongoDB server.

.. attribute:: db

  The :class:`~quart_motor.wrappers.AsyncIOMotorDatabase` if the URI used
  named a database, and ``None`` otherwise.

Wrappers

Quart-Motor wraps Motor's :class:~motor.motor_asyncio.AsyncIOMotorClient, :class:~motor.motor_asyncio.AsyncIOMotorDatabase, and :class:~motor.motor_asyncio.AsyncIOMotorCollection classes, and overrides their attribute and item accessors. Wrapping the Motor classes in this way lets Quart-Motor add methods to AsyncIOMotorCollection while allowing user code to use MongoDB-style dotted expressions.

    >>> type(mongo.cx)
    <type 'quart_motor.wrappers.AsyncIOMotorClient'>
    >>> type(mongo.db)
    <type 'quart_motor.wrappers.AsyncIOMotorDatabase'>
    >>> type(mongo.db.some_collection)
    <type 'quart_motor.wrappers.AsyncIOMotorCollection'>

.. autoclass:: quart_motor.wrappers.AsyncIOMotorCollection(...) :members:

History and Contributors

Changes:

• 2.4.0: Unreleased

  • Flask-PyMongo port as released of Flask-PyMongo.

Flask-PyMongo:

• https://github.com/dcrosta/flask-pymongo

Contributors of Flask-PyMongo:

• jeverling <https://github.com/jeverling>
• tang0th <https://github.com/tang0th>
• Fabrice Aneche <https://github.com/akhenakh>
• Thor Adam <https://github.com/thoradam>
• Christoph Herr <https://github.com/jarus>
• Mark Unsworth <https://github.com/markunsworth>
• Kevin Funk <https://github.com/k-funk>
• Ben Jeffrey <https://github.com/jeffbr13>
• Emmanuel Valette <https://github.com/karec>
• David Awad <https://github.com/DavidAwad>
• Robson Roberto Souza Peixoto <https://github.com/robsonpeixoto>
• juliascript <https://github.com/juliascript>
• Henrik Blidh <https://github.com/hbldh>
• jobou <https://github.com/jbouzekri>
• Craig Davis <https://github.com/blade2005>
• ratson <https://github.com/ratson>
• Abraham Toriz Cruz <https://github.com/categulario>
• MinJae Kwon <https://github.com/mingrammer>
• yarobob <https://github.com/yarobob>
• Andrew C. Hawkins <https://github.com/achawkins>

Contributors of Quart-Motor

• Sriram <https://github.com/marirs>