Last April, we announced the general availability of the Firebase Admin SDK for Python. The initial release of this SDK supported two important features related to Firebase Authentication: minting custom tokens, and verifying ID tokens. Now, we are excited to announce that database support is available in the Firebase Admin SDK for Python starting from version 2.1.0.
Due to the way it's implemented, there are several notable differences between this API and the database APIs found in our other Admin SDKs (Node.js and Java). The most prominent of these differences is the lack of support for realtime event listeners. The Python Admin SDK currently does not provide a way to add event listeners to a database reference in order to receive realtime update notifications. Instead, all data retrieval operations are provided as blocking methods. However, despite these differences there's a lot that can be achieved using this API.
The database module of the Python Admin SDK facilitates both basic data manipulation operations and advanced queries. To begin interacting with the database from a Python environment, initialize the SDK with the Realtime Database URL:
import firebase_admin from firebase_admin import credentials cred = credentials.Cert('path/to/serviceKey.json') firebase_admin.initialize_app(cred, { 'databaseURL' : 'https://my-db.firebaseio.com' })
Then obtain a database reference from the db module of the SDK. Database references expose common database operations as Python methods (get(), set(), push(), update() and delete()):
db
get(), set(), push(), update()
delete()
from firebase_admin import db root = db.reference() # Add a new user under /users. new_user = root.child('users').push({ 'name' : 'Mary Anning', 'since' : 1700 }) # Update a child attribute of the new user. new_user.update({'since' : 1799}) # Obtain a new reference to the user, and retrieve child data. # Result will be made available as a Python dict. mary = db.reference('users/{0}'.format(new_user.key)).get() print 'Name:', mary['name'] print 'Since:', mary['since']
In the Firebase Realtime Database, all data values are stored as JSON. Note how the Python Admin SDK seamlessly converts between JSON and Python's native data types.
To execute an advanced query, call one of the order_by_* methods available on the database reference. This returns a query object, which can be used to specify additional parameters. You can use this API to execute limit queries and range queries against your data, and retrieve sorted results.
order_by_*
from firebase_admin import db dinos = db.reference('dinosaurs') # Retrieve the five tallest dinosaurs in the database sorted by height. # 'result' will be a sorted data structure (list or OrderedDict). result = dinos.order_by_child('height').limit_to_last(5).get() # Retrieve the 5 shortest dinosaurs that are taller than 2m. result = dinos.order_by_child('height').start_at(2).limit_to_first(5).get() # Retrieve the score entries whose values are between 50 and 60. result = db.reference('scores').order_by_value() \ .start_at(50).end_at(60).get()
Take a look at the Admin SDK documentation for more information about this new API. Also check out our Github repo, and help us further improve the Admin SDK by reporting issues and contributing patches. In fact, it was your continuing feedback that motivated us to build and release this API in such a short period. Happy coding with Firebase!
