MongoDB ObjectId converter for Flask framework.

flask_objectid_converter.py

 -*- coding: utf-8 -*-

from werkzeug.routing import BaseConverter
from werkzeug.exceptions import BadRequest
import bson

class ObjectIdConverter(BaseConverter):
    '''Converts string to :class:`~bson.objectid.ObjectId` and
    vise versa::

        @app.route('/users/<ObjectId:user_id>', methods=['GET'])
        def get_user(user_id):
            ...

    To register it in `Flask`, add it to converters dict::

        app.url_map.converters['ObjectId'] = ObjectIdConverter

    Alternative registration way::

        ObjectIdConverter.register_in_flask(app)

    '''

    def to_python(self, value):
        try:
            return bson.ObjectId(value)
        except bson.errors.InvalidId as e:
            raise BadRequest(e)


    def to_url(self, value):
        return str(value)

    @classmethod
    def register_in_flask(cls, flask_app):
        flask_app.url_map.converters['ObjectId'] = cls