Isomorphic DB Adapter

Isomorphic DB adapter is build to using same API with different key/value databases. At the moment supporting indexedDB, Firebase Realtime Database and Firestore

Key capabilities

Because currently service workers and firebase become more and more popular. Large chunk of logic are same in backkend and frontend. Only problem there is different databases are used, with completely different APIs. Another problem, is to migrate project form one environment to another. For Example Firebase Realtime Database to FireStore. In future there can be more adapters for MongoDB, Redis etc.

Another advantage to use these adapters , for example, indexedDB API is very complex, there is simple promise get and set methods.

Installation

    npm install isomorphicdb

Isomorphic db is written by using es6 experimental modules in nodejs. For rollup need to add extensions .mjs.

Also need firebase project to setup. In examples, serviceAccountKeys not included. Copy them from firebase console, in _hidden/serviceAccountKey.mjs folder.

serviceAccountKey.mjs should look like:

export default ({
    "type":                        ...,
    "project_id":                  ...,
    "private_key_id":              ...,
    "private_key":                 ...,
    "client_email":                ...,
    "client_id":                   ...,
    "auth_uri":                    ...,
    "token_uri":                   ...,
    "auth_provider_x509_cert_url": ...,
    "client_x509_cert_url":        ...
});

Firebase Realtime Database Setup.

import serviceAccount from './_hidden/serviceAccountKey';
import admin from 'firebase-admin';

import {firebaseAdapter} from 'isomorpicdb';

const firebase = admin.initializeApp({
    credential:  admin.credential.cert(serviceAccount),
    databaseURL: `https://${serviceAccount.project_id}.firebaseio.com`
}, 'firebase');
const dbName ='test';
const dbVersion = 1;

const db = firebaseAdapter(dbName, dbVersion, firebase.database())

Firestore Setup

import serviceAccount from './_hidden/serviceAccountKey';
import admin from 'firebase-admin';

import {firestoreAdapter} from 'isomorpicdb/';

const firebase = admin.initializeApp({
    credential:  admin.credential.cert(serviceAccount),
    databaseURL: `https://${serviceAccount.project_id}.firebaseio.com`
}, 'firebase');

const dbName ='test';
const dbVersion = 1;

const firestore = firebase.firestore();
firestore.settings({timestampsInSnapshots: true});
const db = firestoreAdapter(dbName, dbVersion, firestore);

IndexedDB Setup

For indexedDB no need serveiceAccount keys.

import {indexedDBAdapter} from 'isomorpicdb';

const dbName ='test';
const dbVersion = 1;

// for unit tests indexedDB can replace with mocks. that's why indexeDB not included in source.
const db = indexedDBAdapter(dbName, dbVersion, indexedDB);

Usage Examples

Now we see, db is object with exact same API, we can use it in different implementations.

We have db adapter above.Now we have query method

const dbCollection = 'users';
const keyPath = '_id';

export default async (driver) => {
    const db = await driver.createObjectStore(dbCollection, {keyPath}).then(_=>_('readwrite'));
    // const {put, get, getAllKeys} = db('readwrite');
    return ({
        addUsers(batch) {
            return Promise.all(batch.map(_ => db.put(_)));
        },
        readIds() {
            return db.getAllKeys();
        },
        readUser(keyPath) {
            return db.get(keyPath);
        }
    })
}

And now we can use it with any db driver.

import query from './query';
import data from './data';


    query(db).then(({addUsers, readUser, readIds}) =>{
        addUsers(data).then(()=>{
            ...
            //data is added
        });
        
        readUser(id).then(({data}) => {
            ...
            //Got user with userID
        });
        
        readIds().then(({data}) => {
            ...
            //get list of user ids
        });

    });

Possibly this not the most useful example, but I tried to show potential, how you with same code, no need to change anything, by using different databases.

API

All driver constructors taking parmeters driver(dbName, version, dbDriver) like in examples above. Driver can create db with readwrite and read permissions. Will return with method createObjectStore(collectionName, {autoincrement?(boolean: false is default),keyPath})

DB methods

get(keyPath): Return data, if keyPath exists.

has(keyPath): return boolean if keyPath exists

put(data): Add data and replace current if no exists. If autoincrement is false, data should contain keyPath field.

add(data): Add data, only if not keyPath exist already. If autoincrement is false, data should contain keyPath field.

update(keyPath,data,force): Merge with existing data with keyPath, with option force is same as put method.

getAllKeys(keyPath?): returning all keys from collection.

delete(keyPath): Delete record with keyPath provided.

All methods will return Promise with following data.

    {
        status:  'Success|Error',
        data,
        message
    }