Method set

lib/associations/belongs-to-many.js:566–658

* Set the associated models by passing an array of instances or their primary keys. * Everything that it not in the passed array will be un-associated. * * @param {Model} sourceInstance source instance to associate new instances with * @param {Model|Model[]|string[]|string|number[]|numbe

(sourceInstance, newAssociatedObjects, options)

   * @returns {Promise}
   */
  async set(sourceInstance, newAssociatedObjects, options) {
    options = options || {};

    const sourceKey = this.sourceKey;
    const targetKey = this.targetKey;
    const identifier = this.identifier;
    const foreignIdentifier = this.foreignIdentifier;

    if (newAssociatedObjects === null) {
      newAssociatedObjects = [];
    } else {
      newAssociatedObjects = this.toInstanceArray(newAssociatedObjects);
    }
    const where = {
      [identifier]: sourceInstance.get(sourceKey),
      ...this.through.scope
    };

    const updateAssociations = currentRows => {
      const obsoleteAssociations = [];
      const promises = [];
      const defaultAttributes = options.through || {};

      const unassociatedObjects = newAssociatedObjects.filter(obj =>
        !currentRows.some(currentRow => currentRow[foreignIdentifier] === obj.get(targetKey))
      );

      for (const currentRow of currentRows) {
        const newObj = newAssociatedObjects.find(obj => currentRow[foreignIdentifier] === obj.get(targetKey));

        if (!newObj) {
          obsoleteAssociations.push(currentRow);
        } else {
          let throughAttributes = newObj[this.through.model.name];
          // Quick-fix for subtle bug when using existing objects that might have the through model attached (not as an attribute object)
          if (throughAttributes instanceof this.through.model) {
            throughAttributes = {};
          }

          const attributes = { ...defaultAttributes, ...throughAttributes };

          if (Object.keys(attributes).length) {
            promises.push(
              this.through.model.update(attributes, Object.assign(options, {
                where: {
                  [identifier]: sourceInstance.get(sourceKey),
                  [foreignIdentifier]: newObj.get(targetKey)
                }
              }
              ))
            );
          }
        }
      }

      if (obsoleteAssociations.length > 0) {
        promises.push(
          this.through.model.destroy({