sequelize/lib/model-manager.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 Toposort = require('toposort-class');
const _ = require('lodash');

class ModelManager {
  constructor(sequelize) {
    this.models = [];
    this.sequelize = sequelize;
  }

  addModel(model) {
    this.models.push(model);
    this.sequelize.models[model.name] = model;

    return model;
  }

  removeModel(modelToRemove) {
    this.models = this.models.filter(model => model.name !== modelToRemove.name);

    delete this.sequelize.models[modelToRemove.name];
  }

  getModel(against, options) {
    options = _.defaults(options || {}, {
      attribute: 'name'
    });

    return this.models.find(model => model[options.attribute] === against);
  }

  get all() {
    return this.models;
  }

  /**
   * Iterate over Models in an order suitable for e.g. creating tables.
   * Will take foreign key constraints into account so that dependencies are visited before dependents.
   *
   * @param {Function} iterator method to execute on each model
   * @param {object} [options] iterator options
   * @private
   */
  forEachModel(iterator, options) {
    const models = {};
    const sorter = new Toposort();
    let sorted;
    let dep;

    options = _.defaults(options || {}, {
      reverse: true
    });

    for (const model of this.models) {
      let deps = [];
      let tableName = model.getTableName();

      if (_.isObject(tableName)) {
        tableName = `${tableName.schema}.${tableName.tableName}`;
      }

      models[tableName] = model;

      for (const attrName in model.rawAttributes) {
        if (Object.prototype.hasOwnProperty.call(model.rawAttributes, attrName)) {
          const attribute = model.rawAttributes[attrName];

          if (attribute.references) {
            dep = attribute.references.model;

            if (_.isObject(dep)) {
              dep = `${dep.schema}.${dep.tableName}`;
            }

            deps.push(dep);
          }
        }
      }

      deps = deps.filter(dep => tableName !== dep);

      sorter.add(tableName, deps);
    }

    sorted = sorter.sort();
    if (options.reverse) {
      sorted = sorted.reverse();
    }
    for (const name of sorted) {
      iterator(models[name], name);
    }
  }
}

module.exports = ModelManager;
module.exports.ModelManager = ModelManager;
module.exports.default = ModelManager;