rx-storage-pouchdb.md

RxStorage PouchDB

The PouchDB RxStorage is based on the PouchDB database. It is the most battle proven RxStorage and has a big ecosystem of adapters. It is the only RxStorage that allows to do replication with a CouchDB endpoint. PouchDB does a lot of overhead to enable CouchDB replication which makes the PouchDB RxStorage one of the slowest.

Pros

• Most battle proven RxStorage
• Supports replication with a CouchDB endpoint
• Support storing attachments
• Big ecosystem of adapters

Cons

• Big bundle size
• Slow performance because of revision handling overhead

Usage

import { createRxDatabase } from 'rxdb';
import { getRxStoragePouch, addPouchPlugin } from 'rxdb/plugins/pouchdb';

addPouchPlugin(require('pouchdb-adapter-idb'));

const db = await createRxDatabase({
    name: 'exampledb',
    storage: getRxStoragePouch(
        'idb',
        {
            /**
             * other pouchdb specific options
             * @link https://pouchdb.com/api.html#create_database
             */
        }
    )
});

Polyfill the global variable

When you use RxDB with angular or other webpack based frameworks, you might get the error Uncaught ReferenceError: global is not defined. This is because pouchdb assumes a nodejs-specific global variable that is not added to browser runtimes by some bundlers. You have to add them by your own, like we do here.

(window as any).global = window;
(window as any).process = {
    env: { DEBUG: undefined },
};

Adapters

PouchDB has many adapters for all JavaScript runtimes.

Using the internal PouchDB Database

For custom operations, you can access the internal PouchDB database. This is dangerous because you might do changes that are not compatible with RxDB. Only use this when there is no way to achieve your goals via the RxDB API.

import {
    getPouchDBOfRxCollection
} from 'rxdb/plugins/pouchdb';

const pouch = getPouchDBOfRxCollection(myRxCollection);