StorageExample.js

'use strict';
import {manager, ReactCBLite} from 'react-native-couchbase-lite';
import EventEmitter from 'EventEmitter';

export const CHANGE_EVENT_TYPE = 'change';
const ERROR_EVENT_TYPE = 'error';

const DB_NAME = 'db'; //'user_123';
const DB_LOCAL_USER_NAME = 'admin';
const DB_LOCAL_PASSWORD = 'password';
const REMOTE_PROTOCOL = 'https://'
const REMOTE_USER = "admin";
const REMOTE_PASSWORD = "password";
const REMOTE_SERVER = "your.server.or.gateway.com:";
const DB_NAME = "";

const Storage = {
  init: function () {
    ReactCBLite.init(5984, DB_LOCAL_USER_NAME, DB_LOCAL_PASSWORD, e => {});
    const REMOTE_DB = `${REMOTE_PROTOCOL}${REMOTE_USER}:${REMOTE_PASSWORD}@${REMOTE_SERVER}:${REMOTE_PORT}/${DB_NAME}/`;

    this.database = new manager(`http://${DB_LOCAL_USER_NAME}:${DB_LOCAL_PASSWORD}@localhost:5984/`, DB_NAME);

    return this.database.createDatabase().then(res => {
      console.log('createDB', res);
    }).then(() => {
      return this.database.replicate(REMOTE_DB, DB_NAME, true);
    }).then((res) => {
      console.log('replicate', REMOTE_DB, res);
    }).catch(error => {
      console.log('ERROR', error);
    })
  },
  getAll: function () {
    return this.database.getAllDocuments();
  },
  get: function(key) {
    return this.database.getDocument(key);
  },
  /**
   * @returns {Promise} a promise with the event listener that the caller can then subscribe to.
   * @throws if the change feed cannot be initialized (eg. last_seq cannot be retrieved from the database)
   * For proper use with React Native see https://colinramsay.co.uk/2015/07/04/react-native-eventemitters.html
   * Emits two possible events:
   *  * 'change' with JSON parsed result from change feed as argument
   *  * 'error' with last error or bad response Errors will be logged automatically to console
   *  After an error there is delay before listening again with exponential backoff.
   */
  getChangesEventEmitter: function() {
    if (!this.changesEventEmitter) {
      this.changesEventEmitter = new EventEmitter();
      this.changesRetryCount = 0;
      return this.database.latestRevision().then(lastRevision => {
        this.lastSequence = lastRevision;
        console.log('INITIAL lastSequence', this.lastSequence);
        this.listenForChange();
        return this.changesEventEmitter;
      })
    } else {
      return new Promise((resolve, reject) => {
        resolve(this.changesEventEmitter);
      });
    }
  },
  /**
   * Override the default change feed options with new options
   * See See Query parameters in http://developer.couchbase.com/documentation/mobile/1.2/develop/references/couchbase-lite/rest-api/database/get-changes/index.html
   * @returns void
   */
  setChangesFeedOptions: function(options) {
    this.changeFeedOptions = options;
  },
  getChangesFeedOptions: function() {
    return Object.assign({feed: 'longpoll'}, this.changeFeedOptions || {}, {since: this.lastSequence});
  },
  listenForChange: function() {
    const params = this.getChangesFeedOptions();
    console.log('Listening for changes with', params);
    return this.database.getChanges(params).then(res => {
      if (typeof(res.last_seq) === 'number') {
        this.lastSequence = res.last_seq;
        console.log('UPDATE lastSequence', this.lastSequence)
        this.changesRetryCount = 0;
        this.changesEventEmitter.emit(CHANGE_EVENT_TYPE, res);
      } else {
        throw new Error(res);
      }
      return this.listenForChange();
    }).catch((error) => {
      this.changesRetryCount += 1;
      console.log('ERROR Listening for changes, RetryCount=', this.changesRetryCount, 'Error=', error);
      this.changesEventEmitter.emit(ERROR_EVENT_TYPE, error);
      return new Promise((resolve, reject) => {
        setTimeout(resolve, (Math.exp(this.changesRetryCount)) + 15 + (Math.random() * 30 * (this.changesRetryCount + 1)));
      }).then(() => { return this.listenForChange() });
    })
  }
};

export default Storage;