cuba-entities.html

<link rel="import" href="../polymer/polymer.html">
<link rel="import" href="../cuba-app/cuba-app-aware-behavior.html">
<link rel="import" href="cuba-data-loading-behavior.html">

<!--
The `cuba-entities` element provides an ability to load list of entities.
-->

<dom-module id="cuba-entities">
  <script>
    Polymer({

      is: 'cuba-entities',

      behaviors: [CubaAppAwareBehavior, CubaDataLoadingBehavior],

      properties: {
        /**
         * Entity name as specified in domain model class via `@Entity` annotation e.g. sec$User
         */
        entityName: String,
        /**
         * Name of the view which is used for loading entities.
         */
        view: {
          type: String,
          value: null
        },
        /**
         * Name of the field to be sorted by. If the name is preceeding by the '+' character,
         * then the sort order is ascending, if by the '-' character then descending.
         * If there is no special character before the property name, then ascending sort will be used.
         */
        sort: {
          type: String,
          value: null
        },
        /**
         * Number of extracted entities.
         */
        limit: {
          type: Number,
          value: null
        },
        /**
         * Position of the first result to retrieve.
         */
        offset: {
          type: Number,
          value: null
        },

        provideCount: {
          type: Boolean,
          value: false
        },

        count: {
          type: Number,
          notify: true,
          readOnly: true
        },

        _loadMoreOffset: {
          type: Number,
          value: null
        }
      },

      observers: [
        '_optionsChanged(app, entityName, view, sort, limit, offset, auto)'
      ],

      /**
       * Deletes entity and removes it from `data` collection.
       * @paprm {Object} must contain `id` and `_entityName` fields
       * @return {Promise}
       */
      remove: function (entity) {
        return this.app.deleteEntity(entity._entityName, entity.id).then(function () {
          if (!this.data || !Array.isArray(this.data)) {
            return;
          }
          if (this.provideCount) {
            this._setCount(this.count - 1);
          }
          for (var i = 0; i < this.data.length; i++) {
            if (this.data[i].id === entity.id) {
              this.splice("data", i, 1);
            }
          }
        }.bind(this));
      },

      loadMore: function () {
        if (!this.data) {
          throw new Error('Data is not loaded yet');
        }
        if (!this.limit) {
          throw new Error('Limit is not specified');
        }

        if (!this._loadMoreOffset) {
          this._loadMoreOffset = this.offset + this.limit;
        } else {
          this._loadMoreOffset += this.limit;
        }
        var options = this._getOptions();
        options.offset = this._loadMoreOffset;
        this._setLoading(true);

        return this.app.loadEntities(this.entityName, options).then(
          function (data) {
            data.forEach(function (v) {
              this.push('data', v);
            }.bind(this));
            this._setLoading(false);
          }.bind(this),
          function() {
            this._setLoading(false);
            this.fire("cuba-data-loading-error");
          }.bind(this)
        );
      },

      loadCount: function(abortable) {
        if (!this.app) {
          return;
        }
        var loadCountPromise = this.app.queryCount(this.entityName, 'all', null);
        loadCountPromise.then(function (count) {
          this._setCount(parseInt(count));
        }.bind(this));
        return loadCountPromise;
      },

      /**
       * @param fetchOptions
       * @returns Promise<object[]>
       * @private
       */
      _load: function (fetchOptions) {
        if (this.app == null || this.entityName == null) {
          return;
        }
        this._loadMoreOffset = null;
        if (this.provideCount) {
          return this.app.loadEntitiesWithCount(this.entityName, this._getOptions(), fetchOptions)
            .then(function (entitiesWithCount) {
              this._setCount(parseInt(entitiesWithCount.count));
              return entitiesWithCount.result;
            }.bind(this));
        } else {
          return this.app.loadEntities(this.entityName, this._getOptions(), fetchOptions);
        }
      },

      _getOptions: function () {
        var opts = {};
        if (this.view) opts.view = this.view;
        if (this.sort) opts.sort = this.sort;
        if (this.limit) opts.limit = this.limit;
        if (this.offset) opts.offset = this.offset;
        return opts;
      }
    });
  </script>
</dom-module>