/**
* MOST Web Framework
* A JavaScript Web Framework
* http://themost.io
* Created by Kyriakos Barbounakis<k.barbounakis@gmail.com> on 2014-10-13.
*
* Copyright (c) 2014, Kyriakos Barbounakis k.barbounakis@gmail.com
Anthi Oikonomou anthioikonomou@gmail.com
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* Neither the name of MOST Web Framework nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* @type {{inherits:Function,_extend:Function}}
* @ignore
*/
var util = require('util'),
qry = require('most-query'),
types = require('./types'),
DataQueryable = require('./data-queryable').DataQueryable;
/**
* @classdesc Represents a one-to-many association between two models.
<p>
This association may be defined in a field of a data model as follows:
</p>
<pre class="prettyprint"><code>
{
"name": "Order", "id": 449, "title": "Order", "hidden": false, "sealed": false,
"abstract": false, "version": "1.0",
"fields": [
...
{
"name": "customer",
"title": "Customer",
"description": "Party placing the order.",
"type": "Party"
}
...
]
}
</code></pre>
<p>
where model Party has a one-to-many association with model Order.
This association may also be defined in parent data model (Party) as follows:
</p>
<pre class="prettyprint"><code>
{
"name": "Party", ...,
"fields": [
...
{
"name": "orders",
"title": "Orders",
"description": "A collection of orders made by the party (Persor or Organization).",
"type": "Order",
"many":true
}
...
]
}
</code></pre>
<p>
where property orders of Party model defines an one-to-many association between Party and Order.
HasManyAssociation class inherits DataQueryable class for filtering, paging, grouping or orderind child items.
</p>
<pre class="prettyprint"><code>
var parties = context.model('Party');
parties.where('id').equal(327).first().then(function(result) {
var party = parties.convert(result);
party.property('orders')
.select('id','orderedItem/name as productName','paymentDue')
.where('paymentMethod/alternateName').equal('DirectDebit')
.list().then(function(result) {
done();
}).catch(function(err) {
done(err);
});
}).catch(function(err) {
done(err);
});
</code></pre>
<pre class="prettyprint"><code>
//Results:
id productName paymentDue
-- -------------------- -----------------------------
6 Alienware X51 (2013) 2015-10-06 18:08:10.000+03:00
7 LaCie Blade Runner 2015-06-16 22:38:52.000+03:00
</code></pre>
* @class
* @constructor
* @augments DataQueryable
* @param {DataObject} obj - A DataObject instance that represents the parent data object
* @param {string|*} association - A string that represents the name of the field which holds association mapping or the association mapping itself.
* @property {DataObject} parent - Gets or sets the parent data object
* @property {DataAssociationMapping} mapping - Gets or sets the mapping definition of this data object association.
*/
function HasManyAssociation(obj, association)
{
/**
* @type {DataObject}
* @private
*/
var parent_ = obj;
/**
* Gets or sets the parent data object
* @type DataObject
*/
Object.defineProperty(this, 'parent', { get: function () {
return parent_;
}, set: function (value) {
parent_ = value;
}, configurable: false, enumerable: false});
var self = this;
if (typeof association === 'string') {
//infer mapping from field name
//set relation mapping
if (self.parent!=null) {
var model = self.parent.getModel();
if (model!=null)
self.mapping = model.inferMapping(association);
}
}
else if (typeof association === 'object' && association !=null) {
//get the specified mapping
if (association instanceof types.DataAssociationMapping)
self.mapping = association;
else
self.mapping = util._extend(new types.DataAssociationMapping(), association);
}
var q = null;
//override query property
Object.defineProperty(this, 'query', {
get:function() {
//if query is already defined
if (q!=null)
//return this query
return q;
if (typeof self.mapping === 'undefined' || self.mapping==null)
throw new Error('Data association mapping cannot be empty at this context.');
//prepare query by selecting the foreign key of the related object
q = qry.query(self.model.viewAdapter).where(self.mapping.childField).equal(self.parent[self.mapping.parentField]).prepare();
return q;
}, configurable:false, enumerable:false
});
var m = null;
//override model property
Object.defineProperty(this, 'model', {
get:function() {
//if query is already defined
if (m!=null)
//return this query
return m;
m = self.parent.context.model(self.mapping.childModel);
return m;
}, configurable:false, enumerable:false
});
}
util.inherits(HasManyAssociation, DataQueryable);
if (typeof exports !== 'undefined')
{
module.exports = {
HasManyAssociation:HasManyAssociation
};
}