Firebase
Firebase is an app development platform built around non-relational technologies. The Firebase Wrapper supports connecting to below objects.
- Authentication Users (read only)
- Firestore Database Documents (read only)
Restoring a logical backup of a database with a materialized view using a foreign table can fail. For this reason, either do not use foreign tables in materialized views or use them in databases with physical backups enabled.
Preparation
Before you can query Firebase, you need to enable the Wrappers extension and store your credentials in Postgres.
Enable Wrappers
Make sure the wrappers extension is installed on your database:
_10create extension if not exists wrappers with schema extensions;
Enable the Firebase Wrapper
Enable the firebase_wrapper FDW:
_10create foreign data wrapper firebase_wrapper_10 handler firebase_fdw_handler_10 validator firebase_fdw_validator;
Store your credentials (optional)
By default, Postgres stores FDW credentials inside pg_catalog.pg_foreign_server in plain text. Anyone with access to this table will be able to view these credentials. Wrappers is designed to work with Vault, which provides an additional level of security for storing credentials. We recommend using Vault to store your credentials.
_11-- Save your Firebase credentials in Vault and retrieve the `key_id`_11insert into vault.secrets (name, secret)_11values (_11 'firebase',_11 '{_11 "type": "service_account",_11 "project_id": "your_gcp_project_id",_11 ..._11 }'_11)_11returning key_id;
Connecting to Firebase
We need to provide Postgres with the credentials to connect to Firebase, and any additional options. We can do this using the create server command:
_10create server firebase_server_10 foreign data wrapper firebase_wrapper_10 options (_10 sa_key_id '<key_ID>', -- The Key ID from above._10 project_id '<firebase_project_id>'_10);
Create a schema
We recommend creating a schema to hold all the foreign tables:
_10create schema if not exists firebase;
Options
The full list of foreign table options are below:
-
object- Object name in Firebase, required.For Authenciation users, the object name is fixed to
auth/users. For Firestore documents, its format isfirestore/<collection_id>, note that collection id must be a full path id. For example,firestore/my-collectionfirestore/my-collection/my-document/another-collection
Entities
Authentication Users
This is an object representing Firebase Authentication Users.
Ref: Firebase Authentication Users
Operations
| Object | Select | Insert | Update | Delete | Truncate |
|---|---|---|---|---|---|
| Authentication Users | ✅ | ❌ | ❌ | ❌ | ❌ |
Usage
_10create foreign table firebase.users (_10 uid text,_10 email text,_10 created_at timestamp,_10 attrs jsonb_10)_10 server firebase_server_10 options (_10 object 'auth/users'_10 );
Notes
- The
attrscolumn contains all user attributes in JSON format - This is a special collection with unique metadata fields
Firestore Database Documents
This is an object representing Firestore Database Documents.
Ref: Firestore Database
Operations
| Object | Select | Insert | Update | Delete | Truncate |
|---|---|---|---|---|---|
| Firestore Database Documents | ✅ | ❌ | ❌ | ❌ | ❌ |
Usage
_10create foreign table firebase.docs (_10 name text,_10 created_at timestamp,_10 updated_at timestamp,_10 attrs jsonb_10)_10 server firebase_server_10 options (_10 object 'firestore/user-profiles'_10 );
Notes
- The
name,created_at, andupdated_atare automatic metadata fields on all Firestore collections - Collection ID must be a full path ID in the format
firestore/<collection_id> - Examples of valid collection paths:
firestore/my-collectionfirestore/my-collection/my-document/another-collection
- The
attrscolumn contains all document attributes in JSON format
Query Pushdown Support
This FDW doesn't support query pushdown.
Examples
Some examples on how to use Firebase foreign tables.
firestore
To map a Firestore collection provide its location using the format firestore/<collection_id> as the object option as shown below.
_10create foreign table firebase.docs (_10 name text,_10 created_at timestamp,_10 updated_at timestamp,_10 attrs jsonb_10)_10 server firebase_server_10 options (_10 object 'firestore/user-profiles'_10 );
Note that name, created_at, and updated_at, are automatic metadata fields on all Firestore collections.
auth/users
The auth/users collection is a special case with unique metadata. The following shows how to map Firebase users to PostgreSQL table.
_10create foreign table firebase.users (_10 uid text,_10 email text,_10 created_at timestamp,_10 attrs jsonb_10)_10 server firebase_server_10 options (_10 object 'auth/users'_10 );