sequelize/lib/associations/has-many.js

Sequelize is a promise-based Node.js ORM tool for Postgres, MySQL, MariaDB, SQLite, Microsoft SQL Server, Amazon Redshift and Snowflake’s Data Cloud. It features solid transaction support, relations, eager and lazy loading, read replication and more.

'use strict';

const Utils = require('./../utils');
const Helpers = require('./helpers');
const _ = require('lodash');
const Association = require('./base');
const Op = require('../operators');

/**
 * One-to-many association
 *
 * In the API reference below, add the name of the association to the method, e.g. for `User.hasMany(Project)` the getter will be `user.getProjects()`.
 * If the association is aliased, use the alias instead, e.g. `User.hasMany(Project, { as: 'jobs' })` will be `user.getJobs()`.
 *
 * @see {@link Model.hasMany}
 */
class HasMany extends Association {
  constructor(source, target, options) {
    super(source, target, options);

    this.associationType = 'HasMany';
    this.targetAssociation = null;
    this.sequelize = source.sequelize;
    this.isMultiAssociation = true;
    this.foreignKeyAttribute = {};

    if (this.options.through) {
      throw new Error('N:M associations are not supported with hasMany. Use belongsToMany instead');
    }

    /*
    * If self association, this is the target association
    */
    if (this.isSelfAssociation) {
      this.targetAssociation = this;
    }

    if (this.as) {
      this.isAliased = true;

      if (_.isPlainObject(this.as)) {
        this.options.name = this.as;
        this.as = this.as.plural;
      } else {
        this.options.name = {
          plural: this.as,
          singular: Utils.singularize(this.as)
        };
      }
    } else {
      this.as = this.target.options.name.plural;
      this.options.name = this.target.options.name;
    }

    /*
     * Foreign key setup
     */
    if (_.isObject(this.options.foreignKey)) {
      this.foreignKeyAttribute = this.options.foreignKey;
      this.foreignKey = this.foreignKeyAttribute.name || this.foreignKeyAttribute.fieldName;
    } else if (this.options.foreignKey) {
      this.foreignKey = this.options.foreignKey;
    }

    if (!this.foreignKey) {
      this.foreignKey = Utils.camelize(
        [
          this.source.options.name.singular,
          this.source.primaryKeyAttribute
        ].join('_')
      );
    }

    if (this.target.rawAttributes[this.foreignKey]) {
      this.identifierField = this.target.rawAttributes[this.foreignKey].field || this.foreignKey;
      this.foreignKeyField = this.target.rawAttributes[this.foreignKey].field || this.foreignKey;
    }

    /*
     * Source key setup
     */
    this.sourceKey = this.options.sourceKey || this.source.primaryKeyAttribute;

    if (this.source.rawAttributes[this.sourceKey]) {
      this.sourceKeyAttribute = this.sourceKey;
      this.sourceKeyField = this.source.rawAttributes[this.sourceKey].field || this.sourceKey;
    } else {
      this.sourceKeyAttribute = this.source.primaryKeyAttribute;
      this.sourceKeyField = this.source.primaryKeyField;
    }

    // Get singular and plural names
    // try to uppercase the first letter, unless the model forbids it
    const plural = _.upperFirst(this.options.name.plural);
    const singular = _.upperFirst(this.options.name.singular);

    this.associationAccessor = this.as;
    this.accessors = {
      get: `get${plural}`,
      set: `set${plural}`,
      addMultiple: `add${plural}`,
      add: `add${singular}`,
      create: `create${singular}`,
      remove: `remove${singular}`,
      removeMultiple: `remove${plural}`,
      hasSingle: `has${singular}`,
      hasAll: `has${plural}`,
      count: `count${plural}`
    };
  }

  // the id is in the target table
  // or in an extra table which connects two tables
  _injectAttributes() {
    const newAttributes = {
      [this.foreignKey]: {
        type: this.options.keyType || this.source.rawAttributes[this.sourceKeyAttribute].type,
        allowNull: true,
        ...this.foreignKeyAttribute
      }
    };

    // Create a new options object for use with addForeignKeyConstraints, to avoid polluting this.options in case it is later used for a n:m
    const constraintOptions = { ...this.options };

    if (this.options.constraints !== false) {
      const target = this.target.rawAttributes[this.foreignKey] || newAttributes[this.foreignKey];
      constraintOptions.onDelete = constraintOptions.onDelete || (target.allowNull ? 'SET NULL' : 'CASCADE');
      constraintOptions.onUpdate = constraintOptions.onUpdate || 'CASCADE';
    }

    Helpers.addForeignKeyConstraints(newAttributes[this.foreignKey], this.source, this.target, constraintOptions, this.sourceKeyField);
    Utils.mergeDefaults(this.target.rawAttributes, newAttributes);

    this.target.refreshAttributes();
    this.source.refreshAttributes();

    this.identifierField = this.target.rawAttributes[this.foreignKey].field || this.foreignKey;
    this.foreignKeyField = this.target.rawAttributes[this.foreignKey].field || this.foreignKey;
    this.sourceKeyField = this.source.rawAttributes[this.sourceKey].field || this.sourceKey;

    Helpers.checkNamingCollision(this);

    return this;
  }

  mixin(obj) {
    const methods = ['get', 'count', 'hasSingle', 'hasAll', 'set', 'add', 'addMultiple', 'remove', 'removeMultiple', 'create'];
    const aliases = {
      hasSingle: 'has',
      hasAll: 'has',
      addMultiple: 'add',
      removeMultiple: 'remove'
    };

    Helpers.mixinMethods(this, obj, methods, aliases);
  }

  /**
   * Get everything currently associated with this, using an optional where clause.
   *
   * @param {Model|Array<Model>} instances source instances
   * @param {object} [options] find options
   * @param {object} [options.where] An optional where clause to limit the associated models
   * @param {string|boolean} [options.scope] Apply a scope on the related model, or remove its default scope by passing false
   * @param {string} [options.schema] Apply a schema on the related model
   *
   * @see
   * {@link Model.findAll}  for a full explanation of options
   *
   * @returns {Promise<Array<Model>>}
   */
  async get(instances, options = {}) {
    const where = {};

    let Model = this.target;
    let instance;
    let values;

    if (!Array.isArray(instances)) {
      instance = instances;
      instances = undefined;
    }

    options = { ...options };

    if (this.scope) {
      Object.assign(where, this.scope);
    }

    if (instances) {
      values = instances.map(_instance => _instance.get(this.sourceKey, { raw: true }));

      if (options.limit && instances.length > 1) {
        options.groupedLimit = {
          limit: options.limit,
          on: this, // association
          values
        };

        delete options.limit;
      } else {
        where[this.foreignKey] = {
          [Op.in]: values
        };
        delete options.groupedLimit;
      }
    } else {
      where[this.foreignKey] = instance.get(this.sourceKey, { raw: true });
    }

    options.where = options.where ?
      { [Op.and]: [where, options.where] } :
      where;

    if (Object.prototype.hasOwnProperty.call(options, 'scope')) {
      if (!options.scope) {
        Model = Model.unscoped();
      } else {
        Model = Model.scope(options.scope);
      }
    }

    if (Object.prototype.hasOwnProperty.call(options, 'schema')) {
      Model = Model.schema(options.schema, options.schemaDelimiter);
    }

    const results = await Model.findAll(options);
    if (instance) return results;

    const result = {};
    for (const _instance of instances) {
      result[_instance.get(this.sourceKey, { raw: true })] = [];
    }

    for (const _instance of results) {
      result[_instance.get(this.foreignKey, { raw: true })].push(_instance);
    }

    return result;
  }

  /**
   * Count everything currently associated with this, using an optional where clause.
   *
   * @param {Model}        instance the source instance
   * @param {object}         [options] find & count options
   * @param {object}         [options.where] An optional where clause to limit the associated models
   * @param {string|boolean} [options.scope] Apply a scope on the related model, or remove its default scope by passing false
   *
   * @returns {Promise<number>}
   */
  async count(instance, options) {
    options = Utils.cloneDeep(options);

    options.attributes = [
      [
        this.sequelize.fn(
          'COUNT',
          this.sequelize.col(`${this.target.name}.${this.target.primaryKeyField}`)
        ),
        'count'
      ]
    ];
    options.raw = true;
    options.plain = true;

    const result = await this.get(instance, options);

    return parseInt(result.count, 10);
  }

  /**
   * Check if one or more rows are associated with `this`.
   *
   * @param {Model} sourceInstance the source instance
   * @param {Model|Model[]|string[]|string|number[]|number} [targetInstances] Can be an array of instances or their primary keys
   * @param {object} [options] Options passed to getAssociations
   *
   * @returns {Promise}
   */
  async has(sourceInstance, targetInstances, options) {
    const where = {};

    if (!Array.isArray(targetInstances)) {
      targetInstances = [targetInstances];
    }

    options = {
      ...options,
      scope: false,
      attributes: [this.target.primaryKeyAttribute],
      raw: true
    };

    where[Op.or] = targetInstances.map(instance => {
      if (instance instanceof this.target) {
        return instance.where();
      }
      return {
        [this.target.primaryKeyAttribute]: instance
      };
    });

    options.where = {
      [Op.and]: [
        where,
        options.where
      ]
    };

    const associatedObjects = await this.get(sourceInstance, options);

    return associatedObjects.length === targetInstances.length;
  }

  /**
   * Set the associated models by passing an array of persisted instances or their primary keys. Everything that is 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[]|number} [targetInstances] An array of persisted instances or primary key of instances to associate with this. Pass `null` or `undefined` to remove all associations.
   * @param {object} [options] Options passed to `target.findAll` and `update`.
   * @param {object} [options.validate] Run validation for the join model
   *
   * @returns {Promise}
   */
  async set(sourceInstance, targetInstances, options) {
    if (targetInstances === null) {
      targetInstances = [];
    } else {
      targetInstances = this.toInstanceArray(targetInstances);
    }

    const oldAssociations = await this.get(sourceInstance, { ...options, scope: false, raw: true });
    const promises = [];
    const obsoleteAssociations = oldAssociations.filter(old =>
      !targetInstances.find(obj =>
        obj[this.target.primaryKeyAttribute] === old[this.target.primaryKeyAttribute]
      )
    );
    const unassociatedObjects = targetInstances.filter(obj =>
      !oldAssociations.find(old =>
        obj[this.target.primaryKeyAttribute] === old[this.target.primaryKeyAttribute]
      )
    );
    let updateWhere;
    let update;

    if (obsoleteAssociations.length > 0) {
      update = {};
      update[this.foreignKey] = null;

      updateWhere = {
        [this.target.primaryKeyAttribute]: obsoleteAssociations.map(associatedObject =>
          associatedObject[this.target.primaryKeyAttribute]
        )
      };


      promises.push(this.target.unscoped().update(
        update,
        {
          ...options,
          where: updateWhere
        }
      ));
    }

    if (unassociatedObjects.length > 0) {
      updateWhere = {};

      update = {};
      update[this.foreignKey] = sourceInstance.get(this.sourceKey);

      Object.assign(update, this.scope);
      updateWhere[this.target.primaryKeyAttribute] = unassociatedObjects.map(unassociatedObject =>
        unassociatedObject[this.target.primaryKeyAttribute]
      );

      promises.push(this.target.unscoped().update(
        update,
        {
          ...options,
          where: updateWhere
        }
      ));
    }

    await Promise.all(promises);

    return sourceInstance;
  }

  /**
   * Associate one or more target rows with `this`. This method accepts a Model / string / number to associate a single row,
   * or a mixed array of Model / string / numbers to associate multiple rows.
   *
   * @param {Model} sourceInstance the source instance
   * @param {Model|Model[]|string[]|string|number[]|number} [targetInstances] A single instance or primary key, or a mixed array of persisted instances or primary keys
   * @param {object} [options] Options passed to `target.update`.
   *
   * @returns {Promise}
   */
  async add(sourceInstance, targetInstances, options = {}) {
    if (!targetInstances) return Promise.resolve();


    targetInstances = this.toInstanceArray(targetInstances);

    const update = {
      [this.foreignKey]: sourceInstance.get(this.sourceKey),
      ...this.scope
    };

    const where = {
      [this.target.primaryKeyAttribute]: targetInstances.map(unassociatedObject =>
        unassociatedObject.get(this.target.primaryKeyAttribute)
      )
    };

    await this.target.unscoped().update(update, { ...options, where });

    return sourceInstance;
  }

  /**
   * Un-associate one or several target rows.
   *
   * @param {Model} sourceInstance instance to un associate instances with
   * @param {Model|Model[]|string|string[]|number|number[]} [targetInstances] Can be an Instance or its primary key, or a mixed array of instances and primary keys
   * @param {object} [options] Options passed to `target.update`
   *
   * @returns {Promise}
   */
  async remove(sourceInstance, targetInstances, options = {}) {
    const update = {
      [this.foreignKey]: null
    };

    targetInstances = this.toInstanceArray(targetInstances);

    const where = {
      [this.foreignKey]: sourceInstance.get(this.sourceKey),
      [this.target.primaryKeyAttribute]: targetInstances.map(targetInstance =>
        targetInstance.get(this.target.primaryKeyAttribute)
      )
    };

    await this.target.unscoped().update(update, { ...options, where });

    return this;
  }

  /**
   * Create a new instance of the associated model and associate it with this.
   *
   * @param {Model} sourceInstance source instance
   * @param {object} [values] values for target model instance
   * @param {object} [options] Options passed to `target.create`
   *
   * @returns {Promise}
   */
  async create(sourceInstance, values, options = {}) {
    if (Array.isArray(options)) {
      options = {
        fields: options
      };
    }

    if (values === undefined) {
      values = {};
    }

    if (this.scope) {
      for (const attribute of Object.keys(this.scope)) {
        values[attribute] = this.scope[attribute];
        if (options.fields) options.fields.push(attribute);
      }
    }

    values[this.foreignKey] = sourceInstance.get(this.sourceKey);
    if (options.fields) options.fields.push(this.foreignKey);
    return await this.target.create(values, options);
  }

  verifyAssociationAlias(alias) {
    if (typeof alias === 'string') {
      return this.as === alias;
    }

    if (alias && alias.plural) {
      return this.as === alias.plural;
    }

    return !this.isAliased;
  }
}

module.exports = HasMany;
module.exports.HasMany = HasMany;
module.exports.default = HasMany;