"PouchDB 5.x + SQLite" AngularJS service for use with "Couchbase Sync Gateway" and "Apache Cordova"

constants.js

(function() {
  'use strict';

  var pouchDbConfiguration = {
    localDbName: 'main',
    remoteDbUrl: 'http://localhost:4984/main'
  };

  angular
    .module('components.databasePouchDb')
    .constant('pouchDbConfiguration', pouchDbConfiguration);
})();

database-nosql-pouchdb.module.js

(function() {
  'use strict';

  angular.module('components.databasePouchDb', []);
})();

database-nosql-pouchdb.service.js

(function() {
  'use strict';

  angular
    .module('components.databasePouchDb')
    .factory('databasePouchDbService', databasePouchDbService);

  databasePouchDbService.$inject = ['$window', '$rootScope', '$q', 'pouchDbConfiguration'];
  function databasePouchDbService($window, $rootScope, $q, pouchDbConfiguration) {
    var db = null;

    var changeListener = null;
    var syncListener = null;

    var service = {
      openDb: function() {
        openDb();
      },
      deleteDb: function() {
        return deleteDb();
      },
      dbInfo: function() {
        return dbInfo();
      },
      save: function(doc) {
        return save(doc);
      },
      get: function(docId, options) {
        return get(docId, options);
      },
      remove: function(docId, docRev) {
        return remove(docId, docRev);
      },
      startListening: function() {
        startListening();
      },
      stopListening: function() {
        stopListening();
      },
      startSyncing: function() {
        startSyncing();
      },
      stopSyncing: function() {
        stopSyncing();
      }
    };

    // ========== Private

    function openDb() {
      db = new $window.PouchDB(pouchDbConfiguration.localDbName, {
        auto_compaction: true,
        adapter: 'websql',
        location: 2
      });
      if (!db.adapter) {
        // websql/sqlite not supported (e.g. FirefoxOS)
        db = new $window.PouchDB(pouchDbConfiguration.localDbName, {
          auto_compaction: true
        });
      }
    }

    function deleteDb() {
      return $q.when(db.destroy());
    }

    function dbInfo() {
      return $q.when(db.info());
    }

    function save(doc) {
      if (!doc._id) {
        doc._id = $window.uuid.v4();
      }

      return $q.when(db.put(doc));
    }

    function get(docId, options) {
      if (options) {
        return $q.when(db.get(docId, options));
      } else {
        return $q.when(db.get(docId));
      }
    }

    function remove(docId, docRev) {
      return $q.when(db.remove(docId, docRev));
    }

    function startListening() {
      changeListener = db.changes({
        live: true,
        include_docs: true
      }).on('change', function(change) {
        if (!change.deleted) {
          $rootScope.$broadcast('databasePouchDbService:change', change);
        } else {
          $rootScope.$broadcast('databasePouchDbService:delete', change);
        }
      }).on('error', function(error) {
        $rootScope.$broadcast('databasePouchDbService:error', error);
      });
    }

    function stopListening() {
      changeListener.cancel();
    }

    function startSyncing() {
      syncListener = db.sync(pouchDbConfiguration.remoteDbUrl, {
        live: true,
        retry: true
      });
    }

    function stopSyncing() {
      syncListener.cancel();
    }

    return service;
  }
})();