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diff --git a/app/static/doc/flask-docs/_sources/patterns/mongokit.txt b/app/static/doc/flask-docs/_sources/patterns/mongokit.txt deleted file mode 100644 index a9c4eef..0000000 --- a/app/static/doc/flask-docs/_sources/patterns/mongokit.txt +++ /dev/null @@ -1,144 +0,0 @@ -.. mongokit-pattern: - -MongoKit in Flask -================= - -Using a document database rather than a full DBMS gets more common these days. -This pattern shows how to use MongoKit, a document mapper library, to -integrate with MongoDB. - -This pattern requires a running MongoDB server and the MongoKit library -installed. - -There are two very common ways to use MongoKit. I will outline each of them -here: - - -Declarative ------------ - -The default behaviour of MongoKit is the declarative one that is based on -common ideas from Django or the SQLAlchemy declarative extension. - -Here an example `app.py` module for your application:: - - from flask import Flask - from mongokit import Connection, Document - - # configuration - MONGODB_HOST = 'localhost' - MONGODB_PORT = 27017 - - # create the little application object - app = Flask(__name__) - app.config.from_object(__name__) - - # connect to the database - connection = Connection(app.config['MONGODB_HOST'], - app.config['MONGODB_PORT']) - - -To define your models, just subclass the `Document` class that is imported -from MongoKit. If you've seen the SQLAlchemy pattern you may wonder why we do -not have a session and even do not define a `init_db` function here. On the -one hand, MongoKit does not have something like a session. This sometimes -makes it more to type but also makes it blazingly fast. On the other hand, -MongoDB is schemaless. This means you can modify the data structure from one -insert query to the next without any problem. MongoKit is just schemaless -too, but implements some validation to ensure data integrity. - -Here is an example document (put this also into `app.py`, e.g.):: - - def max_length(length): - def validate(value): - if len(value) <= length: - return True - raise Exception('%s must be at most %s characters long' % length) - return validate - - class User(Document): - structure = { - 'name': unicode, - 'email': unicode, - } - validators = { - 'name': max_length(50), - 'email': max_length(120) - } - use_dot_notation = True - def __repr__(self): - return '<User %r>' % (self.name) - - # register the User document with our current connection - connection.register([User]) - - -This example shows you how to define your schema (named structure), a -validator for the maximum character length and uses a special MongoKit feature -called `use_dot_notation`. Per default MongoKit behaves like a python -dictionary but with `use_dot_notation` set to `True` you can use your -documents like you use models in nearly any other ORM by using dots to -separate between attributes. - -You can insert entries into the database like this: - ->>> from yourapplication.database import connection ->>> from yourapplication.models import User ->>> collection = connection['test'].users ->>> user = collection.User() ->>> user['name'] = u'admin' ->>> user['email'] = u'admin@localhost' ->>> user.save() - -Note that MongoKit is kinda strict with used column types, you must not use a -common `str` type for either `name` or `email` but unicode. - -Querying is simple as well: - ->>> list(collection.User.find()) -[<User u'admin'>] ->>> collection.User.find_one({'name': u'admin'}) -<User u'admin'> - -.. _MongoKit: http://bytebucket.org/namlook/mongokit/ - - -PyMongo Compatibility Layer ---------------------------- - -If you just want to use PyMongo, you can do that with MongoKit as well. You -may use this process if you need the best performance to get. Note that this -example does not show how to couple it with Flask, see the above MongoKit code -for examples:: - - from MongoKit import Connection - - connection = Connection() - -To insert data you can use the `insert` method. We have to get a -collection first, this is somewhat the same as a table in the SQL world. - ->>> collection = connection['test'].users ->>> user = {'name': u'admin', 'email': u'admin@localhost'} ->>> collection.insert(user) - -print list(collection.find()) -print collection.find_one({'name': u'admin'}) - -MongoKit will automatically commit for us. - -To query your database, you use the collection directly: - ->>> list(collection.find()) -[{u'_id': ObjectId('4c271729e13823182f000000'), u'name': u'admin', u'email': u'admin@localhost'}] ->>> collection.find_one({'name': u'admin'}) -{u'_id': ObjectId('4c271729e13823182f000000'), u'name': u'admin', u'email': u'admin@localhost'} - -These results are also dict-like objects: - ->>> r = collection.find_one({'name': u'admin'}) ->>> r['email'] -u'admin@localhost' - -For more information about MongoKit, head over to the -`website <http://bytebucket.org/namlook/mongokit/>`_. |