931 lines
30 KiB
JavaScript
931 lines
30 KiB
JavaScript
// Copyright IBM Corp. 2013,2015. All Rights Reserved.
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// Node module: loopback-datasource-juggler
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// This file is licensed under the MIT License.
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// License text available at https://opensource.org/licenses/MIT
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var async = require('async');
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var utils = require('./utils');
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var List = require('./list');
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var includeUtils = require('./include_utils');
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var isPlainObject = utils.isPlainObject;
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var defineCachedRelations = utils.defineCachedRelations;
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var uniq = utils.uniq;
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/*!
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* Normalize the include to be an array
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* @param include
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* @returns {*}
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*/
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function normalizeInclude(include) {
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var newInclude;
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if (typeof include === 'string') {
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return [include];
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} else if (isPlainObject(include)) {
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// Build an array of key/value pairs
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newInclude = [];
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var rel = include.rel || include.relation;
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var obj = {};
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if (typeof rel === 'string') {
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obj[rel] = new IncludeScope(include.scope);
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newInclude.push(obj);
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} else {
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for (var key in include) {
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obj[key] = include[key];
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newInclude.push(obj);
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}
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}
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return newInclude;
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} else if (Array.isArray(include)) {
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newInclude = [];
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for (var i = 0, n = include.length; i < n; i++) {
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var subIncludes = normalizeInclude(include[i]);
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newInclude = newInclude.concat(subIncludes);
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}
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return newInclude;
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} else {
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return include;
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}
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}
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function IncludeScope(scope) {
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this._scope = utils.deepMerge({}, scope || {});
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if (this._scope.include) {
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this._include = normalizeInclude(this._scope.include);
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delete this._scope.include;
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} else {
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this._include = null;
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}
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};
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IncludeScope.prototype.conditions = function() {
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return utils.deepMerge({}, this._scope);
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};
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IncludeScope.prototype.include = function() {
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return this._include;
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};
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/**
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* Find the idKey of a Model.
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* @param {ModelConstructor} m - Model Constructor
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* @returns {String}
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*/
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function idName(m) {
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return m.definition.idName() || 'id';
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}
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/*!
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* Look up a model by name from the list of given models
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* @param {Object} models Models keyed by name
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* @param {String} modelName The model name
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* @returns {*} The matching model class
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*/
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function lookupModel(models, modelName) {
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if (models[modelName]) {
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return models[modelName];
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}
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var lookupClassName = modelName.toLowerCase();
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for (var name in models) {
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if (name.toLowerCase() === lookupClassName) {
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return models[name];
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}
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}
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}
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/**
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* Utility Function to allow interleave before and after high computation tasks
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* @param tasks
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* @param callback
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*/
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function execTasksWithInterLeave(tasks, callback) {
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//let's give others some time to process.
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//Context Switch BEFORE Heavy Computation
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process.nextTick(function() {
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//Heavy Computation
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async.parallel(tasks, function(err, info) {
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//Context Switch AFTER Heavy Computation
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process.nextTick(function() {
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callback(err, info);
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});
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});
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});
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}
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/*!
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* Include mixin for ./model.js
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*/
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module.exports = Inclusion;
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/**
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* Inclusion - Model mixin.
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*
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* @class
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*/
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function Inclusion() {
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}
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/**
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* Normalize includes - used in DataAccessObject
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*
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*/
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Inclusion.normalizeInclude = normalizeInclude;
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/**
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* Enables you to load relations of several objects and optimize numbers of requests.
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*
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* Examples:
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*
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* Load all users' posts with only one additional request:
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* `User.include(users, 'posts', function() {});`
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* Or
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* `User.include(users, ['posts'], function() {});`
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*
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* Load all users posts and passports with two additional requests:
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* `User.include(users, ['posts', 'passports'], function() {});`
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*
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* Load all passports owner (users), and all posts of each owner loaded:
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*```Passport.include(passports, {owner: 'posts'}, function() {});
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*``` Passport.include(passports, {owner: ['posts', 'passports']});
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*``` Passport.include(passports, {owner: [{posts: 'images'}, 'passports']});
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*
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* @param {Array} objects Array of instances
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* @param {String|Object|Array} include Which relations to load.
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* @param {Object} [options] Options for CRUD
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* @param {Function} cb Callback called when relations are loaded
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*
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*/
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Inclusion.include = function(objects, include, options, cb) {
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if (typeof options === 'function' && cb === undefined) {
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cb = options;
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options = {};
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}
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var self = this;
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if (!include || (Array.isArray(include) && include.length === 0) ||
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(Array.isArray(objects) && objects.length === 0) ||
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(isPlainObject(include) && Object.keys(include).length === 0)) {
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// The objects are empty
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return process.nextTick(function() {
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cb && cb(null, objects);
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});
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}
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include = normalizeInclude(include);
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async.each(include, function(item, callback) {
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processIncludeItem(objects, item, options, callback);
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}, function(err) {
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cb && cb(err, objects);
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});
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function processIncludeItem(objs, include, options, cb) {
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var relations = self.relations;
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var relationName;
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var subInclude = null, scope = null;
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if (isPlainObject(include)) {
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relationName = Object.keys(include)[0];
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if (include[relationName] instanceof IncludeScope) {
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scope = include[relationName];
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subInclude = scope.include();
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} else {
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subInclude = include[relationName];
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//when include = {user:true}, it does not have subInclude
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if (subInclude === true) {
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subInclude = null;
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}
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}
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} else {
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relationName = include;
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subInclude = null;
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}
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var relation = relations[relationName];
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if (!relation) {
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cb(new Error('Relation "' + relationName + '" is not defined for ' +
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self.modelName + ' model'));
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return;
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}
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var polymorphic = relation.polymorphic;
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//if (polymorphic && !polymorphic.discriminator) {
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// cb(new Error('Relation "' + relationName + '" is polymorphic but ' +
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// 'discriminator is not present'));
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// return;
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//}
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if (!relation.modelTo) {
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if (!relation.polymorphic) {
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cb(new Error('Relation.modelTo is not defined for relation' +
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relationName + ' and is no polymorphic'));
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return;
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}
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}
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// Just skip if inclusion is disabled
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if (relation.options.disableInclude) {
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return cb();
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}
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//prepare filter and fields for making DB Call
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var filter = (scope && scope.conditions()) || {};
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if ((relation.multiple || relation.type === 'belongsTo') && scope) {
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var includeScope = {};
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// make sure not to miss any fields for sub includes
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if (filter.fields && Array.isArray(subInclude) &&
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relation.modelTo.relations) {
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includeScope.fields = [];
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subInclude.forEach(function(name) {
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var rel = relation.modelTo.relations[name];
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if (rel && rel.type === 'belongsTo') {
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includeScope.fields.push(rel.keyFrom);
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}
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});
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}
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utils.mergeQuery(filter, includeScope, { fields: false });
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}
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//Let's add a placeholder where query
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filter.where = filter.where || {};
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//if fields are specified, make sure target foreign key is present
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var fields = filter.fields;
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if (Array.isArray(fields) && fields.indexOf(relation.keyTo) === -1) {
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fields.push(relation.keyTo);
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} else if (isPlainObject(fields) && !fields[relation.keyTo]) {
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fields[relation.keyTo] = true;
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}
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/**
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* call relation specific include functions
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*/
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if (relation.multiple) {
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if (relation.modelThrough) {
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//hasManyThrough needs separate handling
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return includeHasManyThrough(cb);
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}
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//This will also include embedsMany with belongsTo.
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//Might need to optimize db calls for this.
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if (relation.type === 'embedsMany') {
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//embedded docs are part of the objects, no need to make db call.
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//proceed as implemented earlier.
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return includeEmbeds(cb);
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}
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if (relation.type === 'referencesMany') {
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return includeReferencesMany(cb);
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}
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//This handles exactly hasMany. Fast and straightforward. Without parallel, each and other boilerplate.
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if (relation.type === 'hasMany' && relation.multiple && !subInclude) {
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return includeHasManySimple(cb);
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}
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//assuming all other relations with multiple=true as hasMany
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return includeHasMany(cb);
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} else {
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if (polymorphic) {
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if (relation.type === 'hasOne') {
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return includePolymorphicHasOne(cb);
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}
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return includePolymorphicBelongsTo(cb);
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}
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if (relation.type === 'embedsOne') {
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return includeEmbeds(cb);
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}
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//hasOne or belongsTo
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return includeOneToOne(cb);
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}
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/**
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* Handle inclusion of HasManyThrough/HasAndBelongsToMany/Polymorphic
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* HasManyThrough relations
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* @param callback
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*/
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function includeHasManyThrough(callback) {
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var sourceIds = [];
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//Map for Indexing objects by their id for faster retrieval
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var objIdMap = {};
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for (var i = 0; i < objs.length; i++) {
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var obj = objs[i];
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// one-to-many: foreign key reference is modelTo -> modelFrom.
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// use modelFrom.keyFrom in where filter later
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var sourceId = obj[relation.keyFrom];
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if (sourceId) {
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sourceIds.push(sourceId);
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objIdMap[sourceId.toString()] = obj;
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}
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// sourceId can be null. but cache empty data as result
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defineCachedRelations(obj);
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obj.__cachedRelations[relationName] = [];
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}
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//default filters are not applicable on through model. should be applied
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//on modelTo later in 2nd DB call.
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var throughFilter = {
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where: {},
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};
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throughFilter.where[relation.keyTo] = {
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inq: uniq(sourceIds),
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};
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if (polymorphic) {
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//handle polymorphic hasMany (reverse) in which case we need to filter
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//by discriminator to filter other types
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throughFilter.where[polymorphic.discriminator] =
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relation.modelFrom.definition.name;
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}
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/**
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* 1st DB Call of 2 step process. Get through model objects first
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*/
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relation.modelThrough.find(throughFilter, options, throughFetchHandler);
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/**
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* Handle the results of Through model objects and fetch the modelTo items
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* @param err
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* @param {Array<Model>} throughObjs
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* @returns {*}
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*/
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function throughFetchHandler(err, throughObjs) {
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if (err) {
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return callback(err);
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}
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// start preparing for 2nd DB call.
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var targetIds = [];
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var targetObjsMap = {};
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for (var i = 0; i < throughObjs.length; i++) {
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var throughObj = throughObjs[i];
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var targetId = throughObj[relation.keyThrough];
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if (targetId) {
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//save targetIds for 2nd DB Call
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targetIds.push(targetId);
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var sourceObj = objIdMap[throughObj[relation.keyTo]];
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var targetIdStr = targetId.toString();
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//Since targetId can be duplicates, multiple source objs are put
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//into buckets.
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var objList = targetObjsMap[targetIdStr] =
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targetObjsMap[targetIdStr] || [];
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objList.push(sourceObj);
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}
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}
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//Polymorphic relation does not have idKey of modelTo. Find it manually
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var modelToIdName = idName(relation.modelTo);
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filter.where[modelToIdName] = {
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inq: uniq(targetIds),
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};
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//make sure that the modelToIdName is included if fields are specified
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if (Array.isArray(fields) && fields.indexOf(modelToIdName) === -1) {
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fields.push(modelToIdName);
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} else if (isPlainObject(fields) && !fields[modelToIdName]) {
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fields[modelToIdName] = true;
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}
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/**
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* 2nd DB Call of 2 step process. Get modelTo (target) objects
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*/
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relation.modelTo.find(filter, options, targetsFetchHandler);
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function targetsFetchHandler(err, targets) {
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if (err) {
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return callback(err);
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}
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var tasks = [];
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//simultaneously process subIncludes. Call it first as it is an async
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//process.
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if (subInclude && targets) {
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tasks.push(function subIncludesTask(next) {
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relation.modelTo.include(targets, subInclude, options, next);
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});
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}
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//process & link each target with object
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tasks.push(targetLinkingTask);
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function targetLinkingTask(next) {
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async.each(targets, linkManyToMany, next);
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function linkManyToMany(target, next) {
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var targetId = target[modelToIdName];
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var objList = targetObjsMap[targetId.toString()];
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async.each(objList, function(obj, next) {
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if (!obj) return next();
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obj.__cachedRelations[relationName].push(target);
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processTargetObj(obj, next);
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}, next);
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}
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}
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execTasksWithInterLeave(tasks, callback);
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}
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}
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}
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/**
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* Handle inclusion of ReferencesMany relation
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* @param callback
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*/
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function includeReferencesMany(callback) {
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var modelToIdName = idName(relation.modelTo);
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var allTargetIds = [];
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//Map for Indexing objects by their id for faster retrieval
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var targetObjsMap = {};
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for (var i = 0; i < objs.length; i++) {
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var obj = objs[i];
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// one-to-many: foreign key reference is modelTo -> modelFrom.
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// use modelFrom.keyFrom in where filter later
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var targetIds = obj[relation.keyFrom];
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if (targetIds) {
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if (typeof targetIds === 'string') {
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// For relational DBs, the array is stored as stringified json
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// Please note obj is a plain object at this point
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targetIds = JSON.parse(targetIds);
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}
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//referencesMany has multiple targetIds per obj. We need to concat
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// them into allTargetIds before DB Call
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allTargetIds = allTargetIds.concat(targetIds);
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for (var j = 0; j < targetIds.length; j++) {
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var targetId = targetIds[j];
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var targetIdStr = targetId.toString();
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var objList = targetObjsMap[targetIdStr] =
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targetObjsMap[targetIdStr] || [];
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objList.push(obj);
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}
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}
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// sourceId can be null. but cache empty data as result
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defineCachedRelations(obj);
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obj.__cachedRelations[relationName] = [];
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}
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filter.where[relation.keyTo] = {
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inq: uniq(allTargetIds),
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};
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relation.applyScope(null, filter);
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/**
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* Make the DB Call, fetch all target objects
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*/
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relation.modelTo.find(filter, options, targetFetchHandler);
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/**
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* Handle the fetched target objects
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* @param err
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* @param {Array<Model>}targets
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* @returns {*}
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*/
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function targetFetchHandler(err, targets) {
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if (err) {
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return callback(err);
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}
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var tasks = [];
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//simultaneously process subIncludes
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if (subInclude && targets) {
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tasks.push(function subIncludesTask(next) {
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relation.modelTo.include(targets, subInclude, options, next);
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});
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}
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targets = utils.sortObjectsByIds(modelToIdName, allTargetIds, targets);
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//process each target object
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tasks.push(targetLinkingTask);
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function targetLinkingTask(next) {
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async.each(targets, linkManyToMany, next);
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function linkManyToMany(target, next) {
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var objList = targetObjsMap[target[relation.keyTo].toString()];
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async.each(objList, function(obj, next) {
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if (!obj) return next();
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obj.__cachedRelations[relationName].push(target);
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processTargetObj(obj, next);
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}, next);
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}
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}
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execTasksWithInterLeave(tasks, callback);
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}
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}
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/**
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* Handle inclusion of HasMany relation
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* @param callback
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*/
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function includeHasManySimple(callback) {
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//Map for Indexing objects by their id for faster retrieval
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var objIdMap2 = includeUtils.buildOneToOneIdentityMapWithOrigKeys(objs, relation.keyFrom);
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filter.where[relation.keyTo] = {
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inq: uniq(objIdMap2.getKeys()),
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};
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relation.applyScope(null, filter);
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relation.modelTo.find(filter, options, targetFetchHandler);
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function targetFetchHandler(err, targets) {
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if (err) {
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return callback(err);
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}
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var targetsIdMap = includeUtils.buildOneToManyIdentityMapWithOrigKeys(targets, relation.keyTo);
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includeUtils.join(objIdMap2, targetsIdMap, function(obj1, valueToMergeIn) {
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defineCachedRelations(obj1);
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obj1.__cachedRelations[relationName] = valueToMergeIn;
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processTargetObj(obj1, function() {});
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});
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callback(err, objs);
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}
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}
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/**
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* Handle inclusion of HasMany relation
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* @param callback
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*/
|
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function includeHasMany(callback) {
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var sourceIds = [];
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//Map for Indexing objects by their id for faster retrieval
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var objIdMap = {};
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for (var i = 0; i < objs.length; i++) {
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var obj = objs[i];
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// one-to-many: foreign key reference is modelTo -> modelFrom.
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// use modelFrom.keyFrom in where filter later
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var sourceId = obj[relation.keyFrom];
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if (sourceId) {
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sourceIds.push(sourceId);
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objIdMap[sourceId.toString()] = obj;
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}
|
|
// sourceId can be null. but cache empty data as result
|
|
defineCachedRelations(obj);
|
|
obj.__cachedRelations[relationName] = [];
|
|
}
|
|
filter.where[relation.keyTo] = {
|
|
inq: uniq(sourceIds),
|
|
};
|
|
relation.applyScope(null, filter);
|
|
options.partitionBy = relation.keyTo;
|
|
relation.modelTo.find(filter, options, targetFetchHandler);
|
|
/**
|
|
* Process fetched related objects
|
|
* @param err
|
|
* @param {Array<Model>} targets
|
|
* @returns {*}
|
|
*/
|
|
function targetFetchHandler(err, targets) {
|
|
if (err) {
|
|
return callback(err);
|
|
}
|
|
var tasks = [];
|
|
//simultaneously process subIncludes
|
|
if (subInclude && targets) {
|
|
tasks.push(function subIncludesTask(next) {
|
|
relation.modelTo.include(targets, subInclude, options, next);
|
|
});
|
|
}
|
|
//process each target object
|
|
tasks.push(targetLinkingTask);
|
|
function targetLinkingTask(next) {
|
|
if (targets.length === 0) {
|
|
return async.each(objs, function(obj, next) {
|
|
processTargetObj(obj, next);
|
|
}, next);
|
|
}
|
|
|
|
async.each(targets, linkManyToOne, next);
|
|
function linkManyToOne(target, next) {
|
|
//fix for bug in hasMany with referencesMany
|
|
var targetIds = [].concat(target[relation.keyTo]);
|
|
async.each(targetIds, function(targetId, next) {
|
|
var obj = objIdMap[targetId.toString()];
|
|
if (!obj) return next();
|
|
obj.__cachedRelations[relationName].push(target);
|
|
processTargetObj(obj, next);
|
|
}, function(err, processedTargets) {
|
|
if (err) {
|
|
return next(err);
|
|
}
|
|
|
|
var objsWithEmptyRelation = objs.filter(function(obj) {
|
|
return obj.__cachedRelations[relationName].length === 0;
|
|
});
|
|
async.each(objsWithEmptyRelation, function(obj, next) {
|
|
processTargetObj(obj, next);
|
|
}, function(err) {
|
|
next(err, processedTargets);
|
|
});
|
|
});
|
|
}
|
|
}
|
|
|
|
execTasksWithInterLeave(tasks, callback);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Handle Inclusion of Polymorphic BelongsTo relation
|
|
* @param callback
|
|
*/
|
|
function includePolymorphicBelongsTo(callback) {
|
|
var targetIdsByType = {};
|
|
//Map for Indexing objects by their type and targetId for faster retrieval
|
|
var targetObjMapByType = {};
|
|
for (var i = 0; i < objs.length; i++) {
|
|
var obj = objs[i];
|
|
var discriminator = polymorphic.discriminator;
|
|
var modelType = obj[discriminator];
|
|
if (modelType) {
|
|
targetIdsByType[modelType] = targetIdsByType[modelType] || [];
|
|
targetObjMapByType[modelType] = targetObjMapByType[modelType] || {};
|
|
var targetIds = targetIdsByType[modelType];
|
|
var targetObjsMap = targetObjMapByType[modelType];
|
|
var targetId = obj[relation.keyFrom];
|
|
if (targetId) {
|
|
targetIds.push(targetId);
|
|
var targetIdStr = targetId.toString();
|
|
targetObjsMap[targetIdStr] = targetObjsMap[targetIdStr] || [];
|
|
//Is belongsTo. Multiple objects can have the same
|
|
//targetId and therefore map value is an array
|
|
targetObjsMap[targetIdStr].push(obj);
|
|
}
|
|
}
|
|
defineCachedRelations(obj);
|
|
obj.__cachedRelations[relationName] = null;
|
|
}
|
|
async.each(Object.keys(targetIdsByType), processPolymorphicType,
|
|
callback);
|
|
/**
|
|
* Process Polymorphic objects of each type (modelType)
|
|
* @param {String} modelType
|
|
* @param callback
|
|
*/
|
|
function processPolymorphicType(modelType, callback) {
|
|
var typeFilter = { where: {}};
|
|
utils.mergeQuery(typeFilter, filter);
|
|
var targetIds = targetIdsByType[modelType];
|
|
typeFilter.where[relation.keyTo] = {
|
|
inq: uniq(targetIds),
|
|
};
|
|
var Model = lookupModel(relation.modelFrom.dataSource.modelBuilder.
|
|
models, modelType);
|
|
if (!Model) {
|
|
callback(new Error('Discriminator type "' + modelType +
|
|
' specified but no model exists with such name'));
|
|
return;
|
|
}
|
|
relation.applyScope(null, typeFilter);
|
|
Model.find(typeFilter, options, targetFetchHandler);
|
|
/**
|
|
* Process fetched related objects
|
|
* @param err
|
|
* @param {Array<Model>} targets
|
|
* @returns {*}
|
|
*/
|
|
function targetFetchHandler(err, targets) {
|
|
if (err) {
|
|
return callback(err);
|
|
}
|
|
var tasks = [];
|
|
|
|
//simultaneously process subIncludes
|
|
if (subInclude && targets) {
|
|
tasks.push(function subIncludesTask(next) {
|
|
Model.include(targets, subInclude, options, next);
|
|
});
|
|
}
|
|
//process each target object
|
|
tasks.push(targetLinkingTask);
|
|
function targetLinkingTask(next) {
|
|
var targetObjsMap = targetObjMapByType[modelType];
|
|
async.each(targets, linkOneToMany, next);
|
|
function linkOneToMany(target, next) {
|
|
var objList = targetObjsMap[target[relation.keyTo].toString()];
|
|
async.each(objList, function(obj, next) {
|
|
if (!obj) return next();
|
|
obj.__cachedRelations[relationName] = target;
|
|
processTargetObj(obj, next);
|
|
}, next);
|
|
}
|
|
}
|
|
|
|
execTasksWithInterLeave(tasks, callback);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/**
|
|
* Handle Inclusion of Polymorphic HasOne relation
|
|
* @param callback
|
|
*/
|
|
function includePolymorphicHasOne(callback) {
|
|
var sourceIds = [];
|
|
//Map for Indexing objects by their id for faster retrieval
|
|
var objIdMap = {};
|
|
for (var i = 0; i < objs.length; i++) {
|
|
var obj = objs[i];
|
|
// one-to-one: foreign key reference is modelTo -> modelFrom.
|
|
// use modelFrom.keyFrom in where filter later
|
|
var sourceId = obj[relation.keyFrom];
|
|
if (sourceId) {
|
|
sourceIds.push(sourceId);
|
|
objIdMap[sourceId.toString()] = obj;
|
|
}
|
|
// sourceId can be null. but cache empty data as result
|
|
defineCachedRelations(obj);
|
|
obj.__cachedRelations[relationName] = null;
|
|
}
|
|
filter.where[relation.keyTo] = {
|
|
inq: uniq(sourceIds),
|
|
};
|
|
relation.applyScope(null, filter);
|
|
relation.modelTo.find(filter, options, targetFetchHandler);
|
|
/**
|
|
* Process fetched related objects
|
|
* @param err
|
|
* @param {Array<Model>} targets
|
|
* @returns {*}
|
|
*/
|
|
function targetFetchHandler(err, targets) {
|
|
if (err) {
|
|
return callback(err);
|
|
}
|
|
var tasks = [];
|
|
//simultaneously process subIncludes
|
|
if (subInclude && targets) {
|
|
tasks.push(function subIncludesTask(next) {
|
|
relation.modelTo.include(targets, subInclude, options, next);
|
|
});
|
|
}
|
|
//process each target object
|
|
tasks.push(targetLinkingTask);
|
|
function targetLinkingTask(next) {
|
|
async.each(targets, linkOneToOne, next);
|
|
function linkOneToOne(target, next) {
|
|
var sourceId = target[relation.keyTo];
|
|
if (!sourceId) return next();
|
|
var obj = objIdMap[sourceId.toString()];
|
|
if (!obj) return next();
|
|
obj.__cachedRelations[relationName] = target;
|
|
processTargetObj(obj, next);
|
|
}
|
|
}
|
|
|
|
execTasksWithInterLeave(tasks, callback);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Handle Inclusion of BelongsTo/HasOne relation
|
|
* @param callback
|
|
*/
|
|
function includeOneToOne(callback) {
|
|
var targetIds = [];
|
|
var objTargetIdMap = {};
|
|
for (var i = 0; i < objs.length; i++) {
|
|
var obj = objs[i];
|
|
if (relation.type === 'belongsTo') {
|
|
if (obj[relation.keyFrom] === null ||
|
|
obj[relation.keyFrom] === undefined) {
|
|
defineCachedRelations(obj);
|
|
obj.__cachedRelations[relationName] = null;
|
|
continue;
|
|
}
|
|
}
|
|
var targetId = obj[relation.keyFrom];
|
|
if (targetId) {
|
|
targetIds.push(targetId);
|
|
var targetIdStr = targetId.toString();
|
|
objTargetIdMap[targetIdStr] = objTargetIdMap[targetIdStr] || [];
|
|
objTargetIdMap[targetIdStr].push(obj);
|
|
}
|
|
defineCachedRelations(obj);
|
|
obj.__cachedRelations[relationName] = null;
|
|
}
|
|
filter.where[relation.keyTo] = {
|
|
inq: uniq(targetIds),
|
|
};
|
|
relation.applyScope(null, filter);
|
|
relation.modelTo.find(filter, options, targetFetchHandler);
|
|
/**
|
|
* Process fetched related objects
|
|
* @param err
|
|
* @param {Array<Model>} targets
|
|
* @returns {*}
|
|
*/
|
|
function targetFetchHandler(err, targets) {
|
|
if (err) {
|
|
return callback(err);
|
|
}
|
|
var tasks = [];
|
|
//simultaneously process subIncludes
|
|
if (subInclude && targets) {
|
|
tasks.push(function subIncludesTask(next) {
|
|
relation.modelTo.include(targets, subInclude, options, next);
|
|
});
|
|
}
|
|
//process each target object
|
|
tasks.push(targetLinkingTask);
|
|
function targetLinkingTask(next) {
|
|
async.each(targets, linkOneToMany, next);
|
|
function linkOneToMany(target, next) {
|
|
var targetId = target[relation.keyTo];
|
|
var objList = objTargetIdMap[targetId.toString()];
|
|
async.each(objList, function(obj, next) {
|
|
if (!obj) return next();
|
|
obj.__cachedRelations[relationName] = target;
|
|
processTargetObj(obj, next);
|
|
}, next);
|
|
}
|
|
}
|
|
|
|
execTasksWithInterLeave(tasks, callback);
|
|
}
|
|
}
|
|
|
|
|
|
/**
|
|
* Handle Inclusion of EmbedsMany/EmbedsManyWithBelongsTo/EmbedsOne
|
|
* Relations. Since Embedded docs are part of parents, no need to make
|
|
* db calls. Let the related function be called for each object to fetch
|
|
* the results from cache.
|
|
*
|
|
* TODO: Optimize EmbedsManyWithBelongsTo relation DB Calls
|
|
* @param callback
|
|
*/
|
|
function includeEmbeds(callback) {
|
|
async.each(objs, function(obj, next) {
|
|
processTargetObj(obj, next);
|
|
}, callback);
|
|
}
|
|
|
|
/**
|
|
* Process Each Model Object and make sure specified relations are included
|
|
* @param {Model} obj - Single Mode object for which inclusion is needed
|
|
* @param callback
|
|
* @returns {*}
|
|
*/
|
|
function processTargetObj(obj, callback) {
|
|
var isInst = obj instanceof self;
|
|
|
|
// Calling the relation method on the instance
|
|
if (relation.type === 'belongsTo') {
|
|
// If the belongsTo relation doesn't have an owner
|
|
if (obj[relation.keyFrom] === null || obj[relation.keyFrom] === undefined) {
|
|
defineCachedRelations(obj);
|
|
// Set to null if the owner doesn't exist
|
|
obj.__cachedRelations[relationName] = null;
|
|
if (isInst) {
|
|
obj.__data[relationName] = null;
|
|
} else {
|
|
obj[relationName] = null;
|
|
}
|
|
return callback();
|
|
}
|
|
}
|
|
/**
|
|
* Sets the related objects as a property of Parent Object
|
|
* @param {Array<Model>|Model|null} result - Related Object/Objects
|
|
* @param cb
|
|
*/
|
|
function setIncludeData(result, cb) {
|
|
if (isInst) {
|
|
if (Array.isArray(result) && !(result instanceof List)) {
|
|
result = new List(result, relation.modelTo);
|
|
}
|
|
obj.__data[relationName] = result;
|
|
obj.setStrict(false);
|
|
} else {
|
|
obj[relationName] = result;
|
|
}
|
|
cb(null, result);
|
|
}
|
|
|
|
//obj.__cachedRelations[relationName] can be null if no data was returned
|
|
if (obj.__cachedRelations &&
|
|
obj.__cachedRelations[relationName] !== undefined) {
|
|
return setIncludeData(obj.__cachedRelations[relationName],
|
|
callback);
|
|
}
|
|
|
|
var inst = (obj instanceof self) ? obj : new self(obj);
|
|
|
|
//If related objects are not cached by include Handlers, directly call
|
|
//related accessor function even though it is not very efficient
|
|
var related; // relation accessor function
|
|
|
|
if ((relation.multiple || relation.type === 'belongsTo') && scope) {
|
|
var includeScope = {};
|
|
var filter = scope.conditions();
|
|
|
|
// make sure not to miss any fields for sub includes
|
|
if (filter.fields && Array.isArray(subInclude) && relation.modelTo.relations) {
|
|
includeScope.fields = [];
|
|
subInclude.forEach(function(name) {
|
|
var rel = relation.modelTo.relations[name];
|
|
if (rel && rel.type === 'belongsTo') {
|
|
includeScope.fields.push(rel.keyFrom);
|
|
}
|
|
});
|
|
}
|
|
|
|
utils.mergeQuery(filter, includeScope, { fields: false });
|
|
|
|
related = inst[relationName].bind(inst, filter);
|
|
} else {
|
|
related = inst[relationName].bind(inst, undefined);
|
|
}
|
|
|
|
related(options, function(err, result) {
|
|
if (err) {
|
|
return callback(err);
|
|
} else {
|
|
defineCachedRelations(obj);
|
|
obj.__cachedRelations[relationName] = result;
|
|
|
|
return setIncludeData(result, callback);
|
|
}
|
|
});
|
|
}
|
|
}
|
|
};
|