poulpe/shared/static/js/backbone-relational.js
2018-11-21 19:46:41 +01:00

2076 lines
68 KiB
JavaScript

/* vim: set tabstop=4 softtabstop=4 shiftwidth=4 noexpandtab: */
/**
* Backbone-relational.js 0.10.0
* (c) 2011-2014 Paul Uithol and contributors (https://github.com/PaulUithol/Backbone-relational/graphs/contributors)
*
* Backbone-relational may be freely distributed under the MIT license; see the accompanying LICENSE.txt.
* For details and documentation: https://github.com/PaulUithol/Backbone-relational.
* Depends on Backbone (and thus on Underscore as well): https://github.com/documentcloud/backbone.
*
* Example:
*
Zoo = Backbone.RelationalModel.extend({
relations: [ {
type: Backbone.HasMany,
key: 'animals',
relatedModel: 'Animal',
reverseRelation: {
key: 'livesIn',
includeInJSON: 'id'
// 'relatedModel' is automatically set to 'Zoo'; the 'relationType' to 'HasOne'.
}
} ],
toString: function() {
return this.get( 'name' );
}
});
Animal = Backbone.RelationalModel.extend({
toString: function() {
return this.get( 'species' );
}
});
// Creating the zoo will give it a collection with one animal in it: the monkey.
// The animal created after that has a relation `livesIn` that points to the zoo it's currently associated with.
// If you instantiate (or fetch) the zebra later, it will automatically be added.
var zoo = new Zoo({
name: 'Artis',
animals: [ { id: 'monkey-1', species: 'Chimp' }, 'lion-1', 'zebra-1' ]
});
var lion = new Animal( { id: 'lion-1', species: 'Lion' } ),
monkey = zoo.get( 'animals' ).first(),
sameZoo = lion.get( 'livesIn' );
*/
( function( root, factory ) {
// Set up Backbone-relational for the environment. Start with AMD.
if ( typeof define === 'function' && define.amd ) {
define( [ 'exports', 'backbone', 'underscore' ], factory );
}
// Next for Node.js or CommonJS.
else if ( typeof exports !== 'undefined' ) {
factory( exports, require( 'backbone' ), require( 'underscore' ) );
}
// Finally, as a browser global. Use `root` here as it references `window`.
else {
factory( root, root.Backbone, root._ );
}
}( this, function( exports, Backbone, _ ) {
"use strict";
Backbone.Relational = {
showWarnings: true
};
/**
* Semaphore mixin; can be used as both binary and counting.
**/
Backbone.Semaphore = {
_permitsAvailable: null,
_permitsUsed: 0,
acquire: function() {
if ( this._permitsAvailable && this._permitsUsed >= this._permitsAvailable ) {
throw new Error( 'Max permits acquired' );
}
else {
this._permitsUsed++;
}
},
release: function() {
if ( this._permitsUsed === 0 ) {
throw new Error( 'All permits released' );
}
else {
this._permitsUsed--;
}
},
isLocked: function() {
return this._permitsUsed > 0;
},
setAvailablePermits: function( amount ) {
if ( this._permitsUsed > amount ) {
throw new Error( 'Available permits cannot be less than used permits' );
}
this._permitsAvailable = amount;
}
};
/**
* A BlockingQueue that accumulates items while blocked (via 'block'),
* and processes them when unblocked (via 'unblock').
* Process can also be called manually (via 'process').
*/
Backbone.BlockingQueue = function() {
this._queue = [];
};
_.extend( Backbone.BlockingQueue.prototype, Backbone.Semaphore, {
_queue: null,
add: function( func ) {
if ( this.isBlocked() ) {
this._queue.push( func );
}
else {
func();
}
},
// Some of the queued events may trigger other blocking events. By
// copying the queue here it allows queued events to process closer to
// the natural order.
//
// queue events [ 'A', 'B', 'C' ]
// A handler of 'B' triggers 'D' and 'E'
// By copying `this._queue` this executes:
// [ 'A', 'B', 'D', 'E', 'C' ]
// The same order the would have executed if they didn't have to be
// delayed and queued.
process: function() {
var queue = this._queue;
this._queue = [];
while ( queue && queue.length ) {
queue.shift()();
}
},
block: function() {
this.acquire();
},
unblock: function() {
this.release();
if ( !this.isBlocked() ) {
this.process();
}
},
isBlocked: function() {
return this.isLocked();
}
});
/**
* Global event queue. Accumulates external events ('add:<key>', 'remove:<key>' and 'change:<key>')
* until the top-level object is fully initialized (see 'Backbone.RelationalModel').
*/
Backbone.Relational.eventQueue = new Backbone.BlockingQueue();
/**
* Backbone.Store keeps track of all created (and destruction of) Backbone.RelationalModel.
* Handles lookup for relations.
*/
Backbone.Store = function() {
this._collections = [];
this._reverseRelations = [];
this._orphanRelations = [];
this._subModels = [];
this._modelScopes = [ exports ];
};
_.extend( Backbone.Store.prototype, Backbone.Events, {
/**
* Create a new `Relation`.
* @param {Backbone.RelationalModel} [model]
* @param {Object} relation
* @param {Object} [options]
*/
initializeRelation: function( model, relation, options ) {
var type = !_.isString( relation.type ) ? relation.type : Backbone[ relation.type ] || this.getObjectByName( relation.type );
if ( type && type.prototype instanceof Backbone.Relation ) {
var rel = new type( model, relation, options ); // Also pushes the new Relation into `model._relations`
}
else {
Backbone.Relational.showWarnings && typeof console !== 'undefined' && console.warn( 'Relation=%o; missing or invalid relation type!', relation );
}
},
/**
* Add a scope for `getObjectByName` to look for model types by name.
* @param {Object} scope
*/
addModelScope: function( scope ) {
this._modelScopes.push( scope );
},
/**
* Remove a scope.
* @param {Object} scope
*/
removeModelScope: function( scope ) {
this._modelScopes = _.without( this._modelScopes, scope );
},
/**
* Add a set of subModelTypes to the store, that can be used to resolve the '_superModel'
* for a model later in 'setupSuperModel'.
*
* @param {Backbone.RelationalModel} subModelTypes
* @param {Backbone.RelationalModel} superModelType
*/
addSubModels: function( subModelTypes, superModelType ) {
this._subModels.push({
'superModelType': superModelType,
'subModels': subModelTypes
});
},
/**
* Check if the given modelType is registered as another model's subModel. If so, add it to the super model's
* '_subModels', and set the modelType's '_superModel', '_subModelTypeName', and '_subModelTypeAttribute'.
*
* @param {Backbone.RelationalModel} modelType
*/
setupSuperModel: function( modelType ) {
_.find( this._subModels, function( subModelDef ) {
return _.filter( subModelDef.subModels || [], function( subModelTypeName, typeValue ) {
var subModelType = this.getObjectByName( subModelTypeName );
if ( modelType === subModelType ) {
// Set 'modelType' as a child of the found superModel
subModelDef.superModelType._subModels[ typeValue ] = modelType;
// Set '_superModel', '_subModelTypeValue', and '_subModelTypeAttribute' on 'modelType'.
modelType._superModel = subModelDef.superModelType;
modelType._subModelTypeValue = typeValue;
modelType._subModelTypeAttribute = subModelDef.superModelType.prototype.subModelTypeAttribute;
return true;
}
}, this ).length;
}, this );
},
/**
* Add a reverse relation. Is added to the 'relations' property on model's prototype, and to
* existing instances of 'model' in the store as well.
* @param {Object} relation
* @param {Backbone.RelationalModel} relation.model
* @param {String} relation.type
* @param {String} relation.key
* @param {String|Object} relation.relatedModel
*/
addReverseRelation: function( relation ) {
var exists = _.any( this._reverseRelations, function( rel ) {
return _.all( relation || [], function( val, key ) {
return val === rel[ key ];
});
});
if ( !exists && relation.model && relation.type ) {
this._reverseRelations.push( relation );
this._addRelation( relation.model, relation );
this.retroFitRelation( relation );
}
},
/**
* Deposit a `relation` for which the `relatedModel` can't be resolved at the moment.
*
* @param {Object} relation
*/
addOrphanRelation: function( relation ) {
var exists = _.any( this._orphanRelations, function( rel ) {
return _.all( relation || [], function( val, key ) {
return val === rel[ key ];
});
});
if ( !exists && relation.model && relation.type ) {
this._orphanRelations.push( relation );
}
},
/**
* Try to initialize any `_orphanRelation`s
*/
processOrphanRelations: function() {
// Make sure to operate on a copy since we're removing while iterating
_.each( this._orphanRelations.slice( 0 ), function( rel ) {
var relatedModel = Backbone.Relational.store.getObjectByName( rel.relatedModel );
if ( relatedModel ) {
this.initializeRelation( null, rel );
this._orphanRelations = _.without( this._orphanRelations, rel );
}
}, this );
},
/**
*
* @param {Backbone.RelationalModel.constructor} type
* @param {Object} relation
* @private
*/
_addRelation: function( type, relation ) {
if ( !type.prototype.relations ) {
type.prototype.relations = [];
}
type.prototype.relations.push( relation );
_.each( type._subModels || [], function( subModel ) {
this._addRelation( subModel, relation );
}, this );
},
/**
* Add a 'relation' to all existing instances of 'relation.model' in the store
* @param {Object} relation
*/
retroFitRelation: function( relation ) {
var coll = this.getCollection( relation.model, false );
coll && coll.each( function( model ) {
if ( !( model instanceof relation.model ) ) {
return;
}
var rel = new relation.type( model, relation );
}, this );
},
/**
* Find the Store's collection for a certain type of model.
* @param {Backbone.RelationalModel} type
* @param {Boolean} [create=true] Should a collection be created if none is found?
* @return {Backbone.Collection} A collection if found (or applicable for 'model'), or null
*/
getCollection: function( type, create ) {
if ( type instanceof Backbone.RelationalModel ) {
type = type.constructor;
}
var rootModel = type;
while ( rootModel._superModel ) {
rootModel = rootModel._superModel;
}
var coll = _.find( this._collections, function( item ) {
return item.model === rootModel;
});
if ( !coll && create !== false ) {
coll = this._createCollection( rootModel );
}
return coll;
},
/**
* Find a model type on one of the modelScopes by name. Names are split on dots.
* @param {String} name
* @return {Object}
*/
getObjectByName: function( name ) {
var parts = name.split( '.' ),
type = null;
_.find( this._modelScopes, function( scope ) {
type = _.reduce( parts || [], function( memo, val ) {
return memo ? memo[ val ] : undefined;
}, scope );
if ( type && type !== scope ) {
return true;
}
}, this );
return type;
},
_createCollection: function( type ) {
var coll;
// If 'type' is an instance, take its constructor
if ( type instanceof Backbone.RelationalModel ) {
type = type.constructor;
}
// Type should inherit from Backbone.RelationalModel.
if ( type.prototype instanceof Backbone.RelationalModel ) {
coll = new Backbone.Collection();
coll.model = type;
this._collections.push( coll );
}
return coll;
},
/**
* Find the attribute that is to be used as the `id` on a given object
* @param type
* @param {String|Number|Object|Backbone.RelationalModel} item
* @return {String|Number}
*/
resolveIdForItem: function( type, item ) {
var id = _.isString( item ) || _.isNumber( item ) ? item : null;
if ( id === null ) {
if ( item instanceof Backbone.RelationalModel ) {
id = item.id;
}
else if ( _.isObject( item ) ) {
id = item[ type.prototype.idAttribute ];
}
}
// Make all falsy values `null` (except for 0, which could be an id.. see '/issues/179')
if ( !id && id !== 0 ) {
id = null;
}
return id;
},
/**
* Find a specific model of a certain `type` in the store
* @param type
* @param {String|Number|Object|Backbone.RelationalModel} item
*/
find: function( type, item ) {
var id = this.resolveIdForItem( type, item ),
coll = this.getCollection( type );
// Because the found object could be of any of the type's superModel
// types, only return it if it's actually of the type asked for.
if ( coll ) {
var obj = coll.get( id );
if ( obj instanceof type ) {
return obj;
}
}
return null;
},
/**
* Add a 'model' to its appropriate collection. Retain the original contents of 'model.collection'.
* @param {Backbone.RelationalModel} model
*/
register: function( model ) {
var coll = this.getCollection( model );
if ( coll ) {
var modelColl = model.collection;
coll.add( model );
model.collection = modelColl;
}
},
/**
* Check if the given model may use the given `id`
* @param model
* @param [id]
*/
checkId: function( model, id ) {
var coll = this.getCollection( model ),
duplicate = coll && coll.get( id );
if ( duplicate && model !== duplicate ) {
if ( Backbone.Relational.showWarnings && typeof console !== 'undefined' ) {
console.warn( 'Duplicate id! Old RelationalModel=%o, new RelationalModel=%o', duplicate, model );
}
throw new Error( "Cannot instantiate more than one Backbone.RelationalModel with the same id per type!" );
}
},
/**
* Explicitly update a model's id in its store collection
* @param {Backbone.RelationalModel} model
*/
update: function( model ) {
var coll = this.getCollection( model );
// Register a model if it isn't yet (which happens if it was created without an id).
if ( !coll.contains( model ) ) {
this.register( model );
}
// This triggers updating the lookup indices kept in a collection
coll._onModelEvent( 'change:' + model.idAttribute, model, coll );
// Trigger an event on model so related models (having the model's new id in their keyContents) can add it.
model.trigger( 'relational:change:id', model, coll );
},
/**
* Unregister from the store: a specific model, a collection, or a model type.
* @param {Backbone.RelationalModel|Backbone.RelationalModel.constructor|Backbone.Collection} type
*/
unregister: function( type ) {
var coll,
models;
if ( type instanceof Backbone.Model ) {
coll = this.getCollection( type );
models = [ type ];
}
else if ( type instanceof Backbone.Collection ) {
coll = this.getCollection( type.model );
models = _.clone( type.models );
}
else {
coll = this.getCollection( type );
models = _.clone( coll.models );
}
_.each( models, function( model ) {
this.stopListening( model );
_.invoke( model.getRelations(), 'stopListening' );
}, this );
// If we've unregistered an entire store collection, reset the collection (which is much faster).
// Otherwise, remove each model one by one.
if ( _.contains( this._collections, type ) ) {
coll.reset( [] );
}
else {
_.each( models, function( model ) {
if ( coll.get( model ) ) {
coll.remove( model );
}
else {
coll.trigger( 'relational:remove', model, coll );
}
}, this );
}
},
/**
* Reset the `store` to it's original state. The `reverseRelations` are kept though, since attempting to
* re-initialize these on models would lead to a large amount of warnings.
*/
reset: function() {
this.stopListening();
// Unregister each collection to remove event listeners
_.each( this._collections, function( coll ) {
this.unregister( coll );
}, this );
this._collections = [];
this._subModels = [];
this._modelScopes = [ exports ];
}
});
Backbone.Relational.store = new Backbone.Store();
/**
* The main Relation class, from which 'HasOne' and 'HasMany' inherit. Internally, 'relational:<key>' events
* are used to regulate addition and removal of models from relations.
*
* @param {Backbone.RelationalModel} [instance] Model that this relation is created for. If no model is supplied,
* Relation just tries to instantiate it's `reverseRelation` if specified, and bails out after that.
* @param {Object} options
* @param {string} options.key
* @param {Backbone.RelationalModel.constructor} options.relatedModel
* @param {Boolean|String} [options.includeInJSON=true] Serialize the given attribute for related model(s)' in toJSON, or just their ids.
* @param {Boolean} [options.createModels=true] Create objects from the contents of keys if the object is not found in Backbone.store.
* @param {Object} [options.reverseRelation] Specify a bi-directional relation. If provided, Relation will reciprocate
* the relation to the 'relatedModel'. Required and optional properties match 'options', except that it also needs
* {Backbone.Relation|String} type ('HasOne' or 'HasMany').
* @param {Object} opts
*/
Backbone.Relation = function( instance, options, opts ) {
this.instance = instance;
// Make sure 'options' is sane, and fill with defaults from subclasses and this object's prototype
options = _.isObject( options ) ? options : {};
this.reverseRelation = _.defaults( options.reverseRelation || {}, this.options.reverseRelation );
this.options = _.defaults( options, this.options, Backbone.Relation.prototype.options );
this.reverseRelation.type = !_.isString( this.reverseRelation.type ) ? this.reverseRelation.type :
Backbone[ this.reverseRelation.type ] || Backbone.Relational.store.getObjectByName( this.reverseRelation.type );
this.key = this.options.key;
this.keySource = this.options.keySource || this.key;
this.keyDestination = this.options.keyDestination || this.keySource || this.key;
this.model = this.options.model || this.instance.constructor;
this.relatedModel = this.options.relatedModel;
// No 'relatedModel' is interpreted as self-referential
if ( _.isUndefined( this.relatedModel ) ) {
this.relatedModel = this.model;
}
// Otherwise, try to resolve the given value to an object
if ( _.isFunction( this.relatedModel ) && !( this.relatedModel.prototype instanceof Backbone.RelationalModel ) ) {
this.relatedModel = _.result( this, 'relatedModel' );
}
if ( _.isString( this.relatedModel ) ) {
this.relatedModel = Backbone.Relational.store.getObjectByName( this.relatedModel );
}
if ( !this.checkPreconditions() ) {
return;
}
// Add the reverse relation on 'relatedModel' to the store's reverseRelations
if ( !this.options.isAutoRelation && this.reverseRelation.type && this.reverseRelation.key ) {
Backbone.Relational.store.addReverseRelation( _.defaults( {
isAutoRelation: true,
model: this.relatedModel,
relatedModel: this.model,
reverseRelation: this.options // current relation is the 'reverseRelation' for its own reverseRelation
},
this.reverseRelation // Take further properties from this.reverseRelation (type, key, etc.)
) );
}
if ( instance ) {
var contentKey = this.keySource;
if ( contentKey !== this.key && _.isObject( this.instance.get( this.key ) ) ) {
contentKey = this.key;
}
this.setKeyContents( this.instance.get( contentKey ) );
this.relatedCollection = Backbone.Relational.store.getCollection( this.relatedModel );
// Explicitly clear 'keySource', to prevent a leaky abstraction if 'keySource' differs from 'key'.
if ( this.keySource !== this.key ) {
delete this.instance.attributes[ this.keySource ];
}
// Add this Relation to instance._relations
this.instance._relations[ this.key ] = this;
this.initialize( opts );
if ( this.options.autoFetch ) {
this.instance.getAsync( this.key, _.isObject( this.options.autoFetch ) ? this.options.autoFetch : {} );
}
// When 'relatedModel' are created or destroyed, check if it affects this relation.
this.listenTo( this.instance, 'destroy', this.destroy )
.listenTo( this.relatedCollection, 'relational:add relational:change:id', this.tryAddRelated )
.listenTo( this.relatedCollection, 'relational:remove', this.removeRelated );
}
};
// Fix inheritance :\
Backbone.Relation.extend = Backbone.Model.extend;
// Set up all inheritable **Backbone.Relation** properties and methods.
_.extend( Backbone.Relation.prototype, Backbone.Events, Backbone.Semaphore, {
options: {
createModels: true,
includeInJSON: true,
isAutoRelation: false,
autoFetch: false,
parse: false
},
instance: null,
key: null,
keyContents: null,
relatedModel: null,
relatedCollection: null,
reverseRelation: null,
related: null,
/**
* Check several pre-conditions.
* @return {Boolean} True if pre-conditions are satisfied, false if they're not.
*/
checkPreconditions: function() {
var i = this.instance,
k = this.key,
m = this.model,
rm = this.relatedModel,
warn = Backbone.Relational.showWarnings && typeof console !== 'undefined';
if ( !m || !k || !rm ) {
warn && console.warn( 'Relation=%o: missing model, key or relatedModel (%o, %o, %o).', this, m, k, rm );
return false;
}
// Check if the type in 'model' inherits from Backbone.RelationalModel
if ( !( m.prototype instanceof Backbone.RelationalModel ) ) {
warn && console.warn( 'Relation=%o: model does not inherit from Backbone.RelationalModel (%o).', this, i );
return false;
}
// Check if the type in 'relatedModel' inherits from Backbone.RelationalModel
if ( !( rm.prototype instanceof Backbone.RelationalModel ) ) {
warn && console.warn( 'Relation=%o: relatedModel does not inherit from Backbone.RelationalModel (%o).', this, rm );
return false;
}
// Check if this is not a HasMany, and the reverse relation is HasMany as well
if ( this instanceof Backbone.HasMany && this.reverseRelation.type === Backbone.HasMany ) {
warn && console.warn( 'Relation=%o: relation is a HasMany, and the reverseRelation is HasMany as well.', this );
return false;
}
// Check if we're not attempting to create a relationship on a `key` that's already used.
if ( i && _.keys( i._relations ).length ) {
var existing = _.find( i._relations, function( rel ) {
return rel.key === k;
}, this );
if ( existing ) {
warn && console.warn( 'Cannot create relation=%o on %o for model=%o: already taken by relation=%o.',
this, k, i, existing );
return false;
}
}
return true;
},
/**
* Set the related model(s) for this relation
* @param {Backbone.Model|Backbone.Collection} related
*/
setRelated: function( related ) {
this.related = related;
this.instance.attributes[ this.key ] = related;
},
/**
* Determine if a relation (on a different RelationalModel) is the reverse
* relation of the current one.
* @param {Backbone.Relation} relation
* @return {Boolean}
*/
_isReverseRelation: function( relation ) {
return relation.instance instanceof this.relatedModel && this.reverseRelation.key === relation.key &&
this.key === relation.reverseRelation.key;
},
/**
* Get the reverse relations (pointing back to 'this.key' on 'this.instance') for the currently related model(s).
* @param {Backbone.RelationalModel} [model] Get the reverse relations for a specific model.
* If not specified, 'this.related' is used.
* @return {Backbone.Relation[]}
*/
getReverseRelations: function( model ) {
var reverseRelations = [];
// Iterate over 'model', 'this.related.models' (if this.related is a Backbone.Collection), or wrap 'this.related' in an array.
var models = !_.isUndefined( model ) ? [ model ] : this.related && ( this.related.models || [ this.related ] ),
relations = null,
relation = null;
for( var i = 0; i < ( models || [] ).length; i++ ) {
relations = models[ i ].getRelations() || [];
for( var j = 0; j < relations.length; j++ ) {
relation = relations[ j ];
if ( this._isReverseRelation( relation ) ) {
reverseRelations.push( relation );
}
}
}
return reverseRelations;
},
/**
* When `this.instance` is destroyed, cleanup our relations.
* Get reverse relation, call removeRelated on each.
*/
destroy: function() {
this.stopListening();
if ( this instanceof Backbone.HasOne ) {
this.setRelated( null );
}
else if ( this instanceof Backbone.HasMany ) {
this.setRelated( this._prepareCollection() );
}
_.each( this.getReverseRelations(), function( relation ) {
relation.removeRelated( this.instance );
}, this );
}
});
Backbone.HasOne = Backbone.Relation.extend({
options: {
reverseRelation: { type: 'HasMany' }
},
initialize: function( opts ) {
this.listenTo( this.instance, 'relational:change:' + this.key, this.onChange );
var related = this.findRelated( opts );
this.setRelated( related );
// Notify new 'related' object of the new relation.
_.each( this.getReverseRelations(), function( relation ) {
relation.addRelated( this.instance, opts );
}, this );
},
/**
* Find related Models.
* @param {Object} [options]
* @return {Backbone.Model}
*/
findRelated: function( options ) {
var related = null;
options = _.defaults( { parse: this.options.parse }, options );
if ( this.keyContents instanceof this.relatedModel ) {
related = this.keyContents;
}
else if ( this.keyContents || this.keyContents === 0 ) { // since 0 can be a valid `id` as well
var opts = _.defaults( { create: this.options.createModels }, options );
related = this.relatedModel.findOrCreate( this.keyContents, opts );
}
// Nullify `keyId` if we have a related model; in case it was already part of the relation
if ( related ) {
this.keyId = null;
}
return related;
},
/**
* Normalize and reduce `keyContents` to an `id`, for easier comparison
* @param {String|Number|Backbone.Model} keyContents
*/
setKeyContents: function( keyContents ) {
this.keyContents = keyContents;
this.keyId = Backbone.Relational.store.resolveIdForItem( this.relatedModel, this.keyContents );
},
/**
* Event handler for `change:<key>`.
* If the key is changed, notify old & new reverse relations and initialize the new relation.
*/
onChange: function( model, attr, options ) {
// Don't accept recursive calls to onChange (like onChange->findRelated->findOrCreate->initializeRelations->addRelated->onChange)
if ( this.isLocked() ) {
return;
}
this.acquire();
options = options ? _.clone( options ) : {};
// 'options.__related' is set by 'addRelated'/'removeRelated'. If it is set, the change
// is the result of a call from a relation. If it's not, the change is the result of
// a 'set' call on this.instance.
var changed = _.isUndefined( options.__related ),
oldRelated = changed ? this.related : options.__related;
if ( changed ) {
this.setKeyContents( attr );
var related = this.findRelated( options );
this.setRelated( related );
}
// Notify old 'related' object of the terminated relation
if ( oldRelated && this.related !== oldRelated ) {
_.each( this.getReverseRelations( oldRelated ), function( relation ) {
relation.removeRelated( this.instance, null, options );
}, this );
}
// Notify new 'related' object of the new relation. Note we do re-apply even if this.related is oldRelated;
// that can be necessary for bi-directional relations if 'this.instance' was created after 'this.related'.
// In that case, 'this.instance' will already know 'this.related', but the reverse might not exist yet.
_.each( this.getReverseRelations(), function( relation ) {
relation.addRelated( this.instance, options );
}, this );
// Fire the 'change:<key>' event if 'related' was updated
if ( !options.silent && this.related !== oldRelated ) {
var dit = this;
this.changed = true;
Backbone.Relational.eventQueue.add( function() {
dit.instance.trigger( 'change:' + dit.key, dit.instance, dit.related, options, true );
dit.changed = false;
});
}
this.release();
},
/**
* If a new 'this.relatedModel' appears in the 'store', try to match it to the last set 'keyContents'
*/
tryAddRelated: function( model, coll, options ) {
if ( ( this.keyId || this.keyId === 0 ) && model.id === this.keyId ) { // since 0 can be a valid `id` as well
this.addRelated( model, options );
this.keyId = null;
}
},
addRelated: function( model, options ) {
// Allow 'model' to set up its relations before proceeding.
// (which can result in a call to 'addRelated' from a relation of 'model')
var dit = this;
model.queue( function() {
if ( model !== dit.related ) {
var oldRelated = dit.related || null;
dit.setRelated( model );
dit.onChange( dit.instance, model, _.defaults( { __related: oldRelated }, options ) );
}
});
},
removeRelated: function( model, coll, options ) {
if ( !this.related ) {
return;
}
if ( model === this.related ) {
var oldRelated = this.related || null;
this.setRelated( null );
this.onChange( this.instance, model, _.defaults( { __related: oldRelated }, options ) );
}
}
});
Backbone.HasMany = Backbone.Relation.extend({
collectionType: null,
options: {
reverseRelation: { type: 'HasOne' },
collectionType: Backbone.Collection,
collectionKey: true,
collectionOptions: {}
},
initialize: function( opts ) {
this.listenTo( this.instance, 'relational:change:' + this.key, this.onChange );
// Handle a custom 'collectionType'
this.collectionType = this.options.collectionType;
if ( _.isFunction( this.collectionType ) && this.collectionType !== Backbone.Collection && !( this.collectionType.prototype instanceof Backbone.Collection ) ) {
this.collectionType = _.result( this, 'collectionType' );
}
if ( _.isString( this.collectionType ) ) {
this.collectionType = Backbone.Relational.store.getObjectByName( this.collectionType );
}
if ( this.collectionType !== Backbone.Collection && !( this.collectionType.prototype instanceof Backbone.Collection ) ) {
throw new Error( '`collectionType` must inherit from Backbone.Collection' );
}
var related = this.findRelated( opts );
this.setRelated( related );
},
/**
* Bind events and setup collectionKeys for a collection that is to be used as the backing store for a HasMany.
* If no 'collection' is supplied, a new collection will be created of the specified 'collectionType' option.
* @param {Backbone.Collection} [collection]
* @return {Backbone.Collection}
*/
_prepareCollection: function( collection ) {
if ( this.related ) {
this.stopListening( this.related );
}
if ( !collection || !( collection instanceof Backbone.Collection ) ) {
var options = _.isFunction( this.options.collectionOptions ) ?
this.options.collectionOptions( this.instance ) : this.options.collectionOptions;
collection = new this.collectionType( null, options );
}
collection.model = this.relatedModel;
if ( this.options.collectionKey ) {
var key = this.options.collectionKey === true ? this.options.reverseRelation.key : this.options.collectionKey;
if ( collection[ key ] && collection[ key ] !== this.instance ) {
if ( Backbone.Relational.showWarnings && typeof console !== 'undefined' ) {
console.warn( 'Relation=%o; collectionKey=%s already exists on collection=%o', this, key, this.options.collectionKey );
}
}
else if ( key ) {
collection[ key ] = this.instance;
}
}
this.listenTo( collection, 'relational:add', this.handleAddition )
.listenTo( collection, 'relational:remove', this.handleRemoval )
.listenTo( collection, 'relational:reset', this.handleReset );
return collection;
},
/**
* Find related Models.
* @param {Object} [options]
* @return {Backbone.Collection}
*/
findRelated: function( options ) {
var related = null;
options = _.defaults( { parse: this.options.parse }, options );
// Replace 'this.related' by 'this.keyContents' if it is a Backbone.Collection
if ( this.keyContents instanceof Backbone.Collection ) {
this._prepareCollection( this.keyContents );
related = this.keyContents;
}
// Otherwise, 'this.keyContents' should be an array of related object ids.
// Re-use the current 'this.related' if it is a Backbone.Collection; otherwise, create a new collection.
else {
var toAdd = [];
_.each( this.keyContents, function( attributes ) {
var model = null;
if ( attributes instanceof this.relatedModel ) {
model = attributes;
}
else {
// If `merge` is true, update models here, instead of during update.
model = ( _.isObject( attributes ) && options.parse && this.relatedModel.prototype.parse ) ?
this.relatedModel.prototype.parse( _.clone( attributes ), options ) : attributes;
}
model && toAdd.push( model );
}, this );
if ( this.related instanceof Backbone.Collection ) {
related = this.related;
}
else {
related = this._prepareCollection();
}
// By now, `parse` will already have been executed just above for models if specified.
// Disable to prevent additional calls.
related.set( toAdd, _.defaults( { parse: false }, options ) );
}
// Remove entries from `keyIds` that were already part of the relation (and are thus 'unchanged')
this.keyIds = _.difference( this.keyIds, _.pluck( related.models, 'id' ) );
return related;
},
/**
* Normalize and reduce `keyContents` to a list of `ids`, for easier comparison
* @param {String|Number|String[]|Number[]|Backbone.Collection} keyContents
*/
setKeyContents: function( keyContents ) {
this.keyContents = keyContents instanceof Backbone.Collection ? keyContents : null;
this.keyIds = [];
if ( !this.keyContents && ( keyContents || keyContents === 0 ) ) { // since 0 can be a valid `id` as well
// Handle cases the an API/user supplies just an Object/id instead of an Array
this.keyContents = _.isArray( keyContents ) ? keyContents : [ keyContents ];
_.each( this.keyContents, function( item ) {
var itemId = Backbone.Relational.store.resolveIdForItem( this.relatedModel, item );
if ( itemId || itemId === 0 ) {
this.keyIds.push( itemId );
}
}, this );
}
},
/**
* Event handler for `change:<key>`.
* If the contents of the key are changed, notify old & new reverse relations and initialize the new relation.
*/
onChange: function( model, attr, options ) {
options = options ? _.clone( options ) : {};
this.setKeyContents( attr );
this.changed = false;
var related = this.findRelated( options );
this.setRelated( related );
if ( !options.silent ) {
var dit = this;
Backbone.Relational.eventQueue.add( function() {
// The `changed` flag can be set in `handleAddition` or `handleRemoval`
if ( dit.changed ) {
dit.instance.trigger( 'change:' + dit.key, dit.instance, dit.related, options, true );
dit.changed = false;
}
});
}
},
/**
* When a model is added to a 'HasMany', trigger 'add' on 'this.instance' and notify reverse relations.
* (should be 'HasOne', must set 'this.instance' as their related).
*/
handleAddition: function( model, coll, options ) {
//console.debug('handleAddition called; args=%o', arguments);
options = options ? _.clone( options ) : {};
this.changed = true;
_.each( this.getReverseRelations( model ), function( relation ) {
relation.addRelated( this.instance, options );
}, this );
// Only trigger 'add' once the newly added model is initialized (so, has its relations set up)
var dit = this;
!options.silent && Backbone.Relational.eventQueue.add( function() {
dit.instance.trigger( 'add:' + dit.key, model, dit.related, options );
});
},
/**
* When a model is removed from a 'HasMany', trigger 'remove' on 'this.instance' and notify reverse relations.
* (should be 'HasOne', which should be nullified)
*/
handleRemoval: function( model, coll, options ) {
//console.debug('handleRemoval called; args=%o', arguments);
options = options ? _.clone( options ) : {};
this.changed = true;
_.each( this.getReverseRelations( model ), function( relation ) {
relation.removeRelated( this.instance, null, options );
}, this );
var dit = this;
!options.silent && Backbone.Relational.eventQueue.add( function() {
dit.instance.trigger( 'remove:' + dit.key, model, dit.related, options );
});
},
handleReset: function( coll, options ) {
var dit = this;
options = options ? _.clone( options ) : {};
!options.silent && Backbone.Relational.eventQueue.add( function() {
dit.instance.trigger( 'reset:' + dit.key, dit.related, options );
});
},
tryAddRelated: function( model, coll, options ) {
var item = _.contains( this.keyIds, model.id );
if ( item ) {
this.addRelated( model, options );
this.keyIds = _.without( this.keyIds, model.id );
}
},
addRelated: function( model, options ) {
// Allow 'model' to set up its relations before proceeding.
// (which can result in a call to 'addRelated' from a relation of 'model')
var dit = this;
model.queue( function() {
if ( dit.related && !dit.related.get( model ) ) {
dit.related.add( model, _.defaults( { parse: false }, options ) );
}
});
},
removeRelated: function( model, coll, options ) {
if ( this.related.get( model ) ) {
this.related.remove( model, options );
}
}
});
/**
* A type of Backbone.Model that also maintains relations to other models and collections.
* New events when compared to the original:
* - 'add:<key>' (model, related collection, options)
* - 'remove:<key>' (model, related collection, options)
* - 'change:<key>' (model, related model or collection, options)
*/
Backbone.RelationalModel = Backbone.Model.extend({
relations: null, // Relation descriptions on the prototype
_relations: null, // Relation instances
_isInitialized: false,
_deferProcessing: false,
_queue: null,
_attributeChangeFired: false, // Keeps track of `change` event firing under some conditions (like nested `set`s)
subModelTypeAttribute: 'type',
subModelTypes: null,
constructor: function( attributes, options ) {
// Nasty hack, for cases like 'model.get( <HasMany key> ).add( item )'.
// Defer 'processQueue', so that when 'Relation.createModels' is used we trigger 'HasMany'
// collection events only after the model is really fully set up.
// Example: event for "p.on( 'add:jobs' )" -> "p.get('jobs').add( { company: c.id, person: p.id } )".
if ( options && options.collection ) {
var dit = this,
collection = this.collection = options.collection;
// Prevent `collection` from cascading down to nested models; they shouldn't go into this `if` clause.
delete options.collection;
this._deferProcessing = true;
var processQueue = function( model ) {
if ( model === dit ) {
dit._deferProcessing = false;
dit.processQueue();
collection.off( 'relational:add', processQueue );
}
};
collection.on( 'relational:add', processQueue );
// So we do process the queue eventually, regardless of whether this model actually gets added to 'options.collection'.
_.defer( function() {
processQueue( dit );
});
}
Backbone.Relational.store.processOrphanRelations();
Backbone.Relational.store.listenTo( this, 'relational:unregister', Backbone.Relational.store.unregister );
this._queue = new Backbone.BlockingQueue();
this._queue.block();
Backbone.Relational.eventQueue.block();
try {
Backbone.Model.apply( this, arguments );
}
finally {
// Try to run the global queue holding external events
Backbone.Relational.eventQueue.unblock();
}
},
/**
* Override 'trigger' to queue 'change' and 'change:*' events
*/
trigger: function( eventName ) {
if ( eventName.length > 5 && eventName.indexOf( 'change' ) === 0 ) {
var dit = this,
args = arguments;
if ( !Backbone.Relational.eventQueue.isBlocked() ) {
// If we're not in a more complicated nested scenario, fire the change event right away
Backbone.Model.prototype.trigger.apply( dit, args );
}
else {
Backbone.Relational.eventQueue.add( function() {
// Determine if the `change` event is still valid, now that all relations are populated
var changed = true;
if ( eventName === 'change' ) {
// `hasChanged` may have gotten reset by nested calls to `set`.
changed = dit.hasChanged() || dit._attributeChangeFired;
dit._attributeChangeFired = false;
}
else {
var attr = eventName.slice( 7 ),
rel = dit.getRelation( attr );
if ( rel ) {
// If `attr` is a relation, `change:attr` get triggered from `Relation.onChange`.
// These take precedence over `change:attr` events triggered by `Model.set`.
// The relation sets a fourth attribute to `true`. If this attribute is present,
// continue triggering this event; otherwise, it's from `Model.set` and should be stopped.
changed = ( args[ 4 ] === true );
// If this event was triggered by a relation, set the right value in `this.changed`
// (a Collection or Model instead of raw data).
if ( changed ) {
dit.changed[ attr ] = args[ 2 ];
}
// Otherwise, this event is from `Model.set`. If the relation doesn't report a change,
// remove attr from `dit.changed` so `hasChanged` doesn't take it into account.
else if ( !rel.changed ) {
delete dit.changed[ attr ];
}
}
else if ( changed ) {
dit._attributeChangeFired = true;
}
}
changed && Backbone.Model.prototype.trigger.apply( dit, args );
});
}
}
else if ( eventName === 'destroy' ) {
Backbone.Model.prototype.trigger.apply( this, arguments );
Backbone.Relational.store.unregister( this );
}
else {
Backbone.Model.prototype.trigger.apply( this, arguments );
}
return this;
},
/**
* Initialize Relations present in this.relations; determine the type (HasOne/HasMany), then creates a new instance.
* Invoked in the first call so 'set' (which is made from the Backbone.Model constructor).
*/
initializeRelations: function( options ) {
this.acquire(); // Setting up relations often also involve calls to 'set', and we only want to enter this function once
this._relations = {};
_.each( this.relations || [], function( rel ) {
Backbone.Relational.store.initializeRelation( this, rel, options );
}, this );
this._isInitialized = true;
this.release();
this.processQueue();
},
/**
* When new values are set, notify this model's relations (also if options.silent is set).
* (called from `set`; Relation.setRelated locks this model before calling 'set' on it to prevent loops)
* @param {Object} [changedAttrs]
* @param {Object} [options]
*/
updateRelations: function( changedAttrs, options ) {
if ( this._isInitialized && !this.isLocked() ) {
_.each( this._relations, function( rel ) {
if ( !changedAttrs || ( rel.keySource in changedAttrs || rel.key in changedAttrs ) ) {
// Fetch data in `rel.keySource` if data got set in there, or `rel.key` otherwise
var value = this.attributes[ rel.keySource ] || this.attributes[ rel.key ],
attr = changedAttrs && ( changedAttrs[ rel.keySource ] || changedAttrs[ rel.key ] );
// Update a relation if its value differs from this model's attributes, or it's been explicitly nullified.
// Which can also happen before the originally intended related model has been found (`val` is null).
if ( rel.related !== value || ( value === null && attr === null ) ) {
this.trigger( 'relational:change:' + rel.key, this, value, options || {} );
}
}
// Explicitly clear 'keySource', to prevent a leaky abstraction if 'keySource' differs from 'key'.
if ( rel.keySource !== rel.key ) {
delete this.attributes[ rel.keySource ];
}
}, this );
}
},
/**
* Either add to the queue (if we're not initialized yet), or execute right away.
*/
queue: function( func ) {
this._queue.add( func );
},
/**
* Process _queue
*/
processQueue: function() {
if ( this._isInitialized && !this._deferProcessing && this._queue.isBlocked() ) {
this._queue.unblock();
}
},
/**
* Get a specific relation.
* @param {string} attr The relation key to look for.
* @return {Backbone.Relation} An instance of 'Backbone.Relation', if a relation was found for 'attr', or null.
*/
getRelation: function( attr ) {
return this._relations[ attr ];
},
/**
* Get all of the created relations.
* @return {Backbone.Relation[]}
*/
getRelations: function() {
return _.values( this._relations );
},
/**
* Get a list of ids that will be fetched on a call to `getAsync`.
* @param {string|Backbone.Relation} attr The relation key to fetch models for.
* @param [refresh=false] Add ids for models that are already in the relation, refreshing them?
* @return {Array} An array of ids that need to be fetched.
*/
getIdsToFetch: function( attr, refresh ) {
var rel = attr instanceof Backbone.Relation ? attr : this.getRelation( attr ),
ids = rel ? ( rel.keyIds && rel.keyIds.slice( 0 ) ) || ( ( rel.keyId || rel.keyId === 0 ) ? [ rel.keyId ] : [] ) : [];
// On `refresh`, add the ids for current models in the relation to `idsToFetch`
if ( refresh ) {
var models = rel.related && ( rel.related.models || [ rel.related ] );
_.each( models, function( model ) {
if ( model.id || model.id === 0 ) {
ids.push( model.id );
}
});
}
return ids;
},
/**
* Get related objects. Returns a single promise, which can either resolve immediately (if the related model[s])
* are already present locally, or after fetching the contents of the requested attribute.
* @param {string} attr The relation key to fetch models for.
* @param {Object} [options] Options for 'Backbone.Model.fetch' and 'Backbone.sync'.
* @param {Boolean} [options.refresh=false] Fetch existing models from the server as well (in order to update them).
* @return {jQuery.Deferred} A jQuery promise object. When resolved, its `done` callback will be called with
* contents of `attr`.
*/
getAsync: function( attr, options ) {
// Set default `options` for fetch
options = _.extend( { add: true, remove: false, refresh: false }, options );
var dit = this,
requests = [],
rel = this.getRelation( attr ),
idsToFetch = rel && this.getIdsToFetch( rel, options.refresh ),
coll = rel.related instanceof Backbone.Collection ? rel.related : rel.relatedCollection;
if ( idsToFetch && idsToFetch.length ) {
var models = [],
createdModels = [],
setUrl,
createModels = function() {
// Find (or create) a model for each one that is to be fetched
models = _.map( idsToFetch, function( id ) {
var model = rel.relatedModel.findModel( id );
if ( !model ) {
var attrs = {};
attrs[ rel.relatedModel.prototype.idAttribute ] = id;
model = rel.relatedModel.findOrCreate( attrs, options );
createdModels.push( model );
}
return model;
}, this );
};
// Try if the 'collection' can provide a url to fetch a set of models in one request.
// This assumes that when 'Backbone.Collection.url' is a function, it can handle building of set urls.
// To make sure it can, test if the url we got by supplying a list of models to fetch is different from
// the one supplied for the default fetch action (without args to 'url').
if ( coll instanceof Backbone.Collection && _.isFunction( coll.url ) ) {
var defaultUrl = coll.url();
setUrl = coll.url( idsToFetch );
if ( setUrl === defaultUrl ) {
createModels();
setUrl = coll.url( models );
if ( setUrl === defaultUrl ) {
setUrl = null;
}
}
}
if ( setUrl ) {
// Do a single request to fetch all models
var opts = _.defaults(
{
error: function() {
_.each( createdModels, function( model ) {
model.trigger( 'destroy', model, model.collection, options );
});
options.error && options.error.apply( models, arguments );
},
url: setUrl
},
options
);
requests = [ coll.fetch( opts ) ];
}
else {
// Make a request per model to fetch
if ( !models.length ) {
createModels();
}
requests = _.map( models, function( model ) {
var opts = _.defaults(
{
error: function() {
if ( _.contains( createdModels, model ) ) {
model.trigger( 'destroy', model, model.collection, options );
}
options.error && options.error.apply( models, arguments );
}
},
options
);
return model.fetch( opts );
}, this );
}
}
return this.deferArray(requests).then(
function() {
return Backbone.Model.prototype.get.call( dit, attr );
}
);
},
deferArray: function(deferArray) {
return Backbone.$.when.apply(null, deferArray);
},
set: function( key, value, options ) {
Backbone.Relational.eventQueue.block();
// Duplicate backbone's behavior to allow separate key/value parameters, instead of a single 'attributes' object
var attributes,
result;
if ( _.isObject( key ) || key == null ) {
attributes = key;
options = value;
}
else {
attributes = {};
attributes[ key ] = value;
}
try {
var id = this.id,
newId = attributes && this.idAttribute in attributes && attributes[ this.idAttribute ];
// Check if we're not setting a duplicate id before actually calling `set`.
Backbone.Relational.store.checkId( this, newId );
result = Backbone.Model.prototype.set.apply( this, arguments );
// Ideal place to set up relations, if this is the first time we're here for this model
if ( !this._isInitialized && !this.isLocked() ) {
this.constructor.initializeModelHierarchy();
// Only register models that have an id. A model will be registered when/if it gets an id later on.
if ( newId || newId === 0 ) {
Backbone.Relational.store.register( this );
}
this.initializeRelations( options );
}
// The store should know about an `id` update asap
else if ( newId && newId !== id ) {
Backbone.Relational.store.update( this );
}
if ( attributes ) {
this.updateRelations( attributes, options );
}
}
finally {
// Try to run the global queue holding external events
Backbone.Relational.eventQueue.unblock();
}
return result;
},
clone: function() {
var attributes = _.clone( this.attributes );
if ( !_.isUndefined( attributes[ this.idAttribute ] ) ) {
attributes[ this.idAttribute ] = null;
}
_.each( this.getRelations(), function( rel ) {
delete attributes[ rel.key ];
});
return new this.constructor( attributes );
},
/**
* Convert relations to JSON, omits them when required
*/
toJSON: function( options ) {
// If this Model has already been fully serialized in this branch once, return to avoid loops
if ( this.isLocked() ) {
return this.id;
}
this.acquire();
var json = Backbone.Model.prototype.toJSON.call( this, options );
if ( this.constructor._superModel && !( this.constructor._subModelTypeAttribute in json ) ) {
json[ this.constructor._subModelTypeAttribute ] = this.constructor._subModelTypeValue;
}
_.each( this._relations, function( rel ) {
var related = json[ rel.key ],
includeInJSON = rel.options.includeInJSON,
value = null;
if ( includeInJSON === true ) {
if ( related && _.isFunction( related.toJSON ) ) {
value = related.toJSON( options );
}
}
else if ( _.isString( includeInJSON ) ) {
if ( related instanceof Backbone.Collection ) {
value = related.pluck( includeInJSON );
}
else if ( related instanceof Backbone.Model ) {
value = related.get( includeInJSON );
}
// Add ids for 'unfound' models if includeInJSON is equal to (only) the relatedModel's `idAttribute`
if ( includeInJSON === rel.relatedModel.prototype.idAttribute ) {
if ( rel instanceof Backbone.HasMany ) {
value = value.concat( rel.keyIds );
}
else if ( rel instanceof Backbone.HasOne ) {
value = value || rel.keyId;
if ( !value && !_.isObject( rel.keyContents ) ) {
value = rel.keyContents || null;
}
}
}
}
else if ( _.isArray( includeInJSON ) ) {
if ( related instanceof Backbone.Collection ) {
value = [];
related.each( function( model ) {
var curJson = {};
_.each( includeInJSON, function( key ) {
curJson[ key ] = model.get( key );
});
value.push( curJson );
});
}
else if ( related instanceof Backbone.Model ) {
value = {};
_.each( includeInJSON, function( key ) {
value[ key ] = related.get( key );
});
}
}
else {
delete json[ rel.key ];
}
// In case of `wait: true`, Backbone will simply push whatever's passed into `save` into attributes.
// We'll want to get this information into the JSON, even if it doesn't conform to our normal
// expectations of what's contained in it (no model/collection for a relation, etc).
if ( value === null && options && options.wait ) {
value = related;
}
if ( includeInJSON ) {
json[ rel.keyDestination ] = value;
}
if ( rel.keyDestination !== rel.key ) {
delete json[ rel.key ];
}
});
this.release();
return json;
}
},
{
/**
*
* @param superModel
* @returns {Backbone.RelationalModel.constructor}
*/
setup: function( superModel ) {
// We don't want to share a relations array with a parent, as this will cause problems with reverse
// relations. Since `relations` may also be a property or function, only use slice if we have an array.
this.prototype.relations = ( this.prototype.relations || [] ).slice( 0 );
this._subModels = {};
this._superModel = null;
// If this model has 'subModelTypes' itself, remember them in the store
if ( this.prototype.hasOwnProperty( 'subModelTypes' ) ) {
Backbone.Relational.store.addSubModels( this.prototype.subModelTypes, this );
}
// The 'subModelTypes' property should not be inherited, so reset it.
else {
this.prototype.subModelTypes = null;
}
// Initialize all reverseRelations that belong to this new model.
_.each( this.prototype.relations || [], function( rel ) {
if ( !rel.model ) {
rel.model = this;
}
if ( rel.reverseRelation && rel.model === this ) {
var preInitialize = true;
if ( _.isString( rel.relatedModel ) ) {
/**
* The related model might not be defined for two reasons
* 1. it is related to itself
* 2. it never gets defined, e.g. a typo
* 3. the model hasn't been defined yet, but will be later
* In neither of these cases do we need to pre-initialize reverse relations.
* However, for 3. (which is, to us, indistinguishable from 2.), we do need to attempt
* setting up this relation again later, in case the related model is defined later.
*/
var relatedModel = Backbone.Relational.store.getObjectByName( rel.relatedModel );
preInitialize = relatedModel && ( relatedModel.prototype instanceof Backbone.RelationalModel );
}
if ( preInitialize ) {
Backbone.Relational.store.initializeRelation( null, rel );
}
else if ( _.isString( rel.relatedModel ) ) {
Backbone.Relational.store.addOrphanRelation( rel );
}
}
}, this );
return this;
},
/**
* Create a 'Backbone.Model' instance based on 'attributes'.
* @param {Object} attributes
* @param {Object} [options]
* @return {Backbone.Model}
*/
build: function( attributes, options ) {
// 'build' is a possible entrypoint; it's possible no model hierarchy has been determined yet.
this.initializeModelHierarchy();
// Determine what type of (sub)model should be built if applicable.
var model = this._findSubModelType( this, attributes ) || this;
return new model( attributes, options );
},
/**
* Determines what type of (sub)model should be built if applicable.
* Looks up the proper subModelType in 'this._subModels', recursing into
* types until a match is found. Returns the applicable 'Backbone.Model'
* or null if no match is found.
* @param {Backbone.Model} type
* @param {Object} attributes
* @return {Backbone.Model}
*/
_findSubModelType: function( type, attributes ) {
if ( type._subModels && type.prototype.subModelTypeAttribute in attributes ) {
var subModelTypeAttribute = attributes[ type.prototype.subModelTypeAttribute ];
var subModelType = type._subModels[ subModelTypeAttribute ];
if ( subModelType ) {
return subModelType;
}
else {
// Recurse into subModelTypes to find a match
for ( subModelTypeAttribute in type._subModels ) {
subModelType = this._findSubModelType( type._subModels[ subModelTypeAttribute ], attributes );
if ( subModelType ) {
return subModelType;
}
}
}
}
return null;
},
/**
*
*/
initializeModelHierarchy: function() {
// Inherit any relations that have been defined in the parent model.
this.inheritRelations();
// If we came here through 'build' for a model that has 'subModelTypes' then try to initialize the ones that
// haven't been resolved yet.
if ( this.prototype.subModelTypes ) {
var resolvedSubModels = _.keys( this._subModels );
var unresolvedSubModels = _.omit( this.prototype.subModelTypes, resolvedSubModels );
_.each( unresolvedSubModels, function( subModelTypeName ) {
var subModelType = Backbone.Relational.store.getObjectByName( subModelTypeName );
subModelType && subModelType.initializeModelHierarchy();
});
}
},
inheritRelations: function() {
// Bail out if we've been here before.
if ( !_.isUndefined( this._superModel ) && !_.isNull( this._superModel ) ) {
return;
}
// Try to initialize the _superModel.
Backbone.Relational.store.setupSuperModel( this );
// If a superModel has been found, copy relations from the _superModel if they haven't been inherited automatically
// (due to a redefinition of 'relations').
if ( this._superModel ) {
// The _superModel needs a chance to initialize its own inherited relations before we attempt to inherit relations
// from the _superModel. You don't want to call 'initializeModelHierarchy' because that could cause sub-models of
// this class to inherit their relations before this class has had chance to inherit it's relations.
this._superModel.inheritRelations();
if ( this._superModel.prototype.relations ) {
// Find relations that exist on the '_superModel', but not yet on this model.
var inheritedRelations = _.filter( this._superModel.prototype.relations || [], function( superRel ) {
return !_.any( this.prototype.relations || [], function( rel ) {
return superRel.relatedModel === rel.relatedModel && superRel.key === rel.key;
}, this );
}, this );
this.prototype.relations = inheritedRelations.concat( this.prototype.relations );
}
}
// Otherwise, make sure we don't get here again for this type by making '_superModel' false so we fail the
// isUndefined/isNull check next time.
else {
this._superModel = false;
}
},
/**
* Find an instance of `this` type in 'Backbone.Relational.store'.
* A new model is created if no matching model is found, `attributes` is an object, and `options.create` is true.
* - If `attributes` is a string or a number, `findOrCreate` will query the `store` and return a model if found.
* - If `attributes` is an object and is found in the store, the model will be updated with `attributes` unless `options.merge` is `false`.
* @param {Object|String|Number} attributes Either a model's id, or the attributes used to create or update a model.
* @param {Object} [options]
* @param {Boolean} [options.create=true]
* @param {Boolean} [options.merge=true]
* @param {Boolean} [options.parse=false]
* @return {Backbone.RelationalModel}
*/
findOrCreate: function( attributes, options ) {
options || ( options = {} );
var parsedAttributes = ( _.isObject( attributes ) && options.parse && this.prototype.parse ) ?
this.prototype.parse( _.clone( attributes ), options ) : attributes;
// If specified, use a custom `find` function to match up existing models to the given attributes.
// Otherwise, try to find an instance of 'this' model type in the store
var model = this.findModel( parsedAttributes );
// If we found an instance, update it with the data in 'item' (unless 'options.merge' is false).
// If not, create an instance (unless 'options.create' is false).
if ( _.isObject( attributes ) ) {
if ( model && options.merge !== false ) {
// Make sure `options.collection` and `options.url` doesn't cascade to nested models
delete options.collection;
delete options.url;
model.set( parsedAttributes, options );
}
else if ( !model && options.create !== false ) {
model = this.build( parsedAttributes, _.defaults( { parse: false }, options ) );
}
}
return model;
},
/**
* Find an instance of `this` type in 'Backbone.Relational.store'.
* - If `attributes` is a string or a number, `find` will query the `store` and return a model if found.
* - If `attributes` is an object and is found in the store, the model will be updated with `attributes` unless `options.merge` is `false`.
* @param {Object|String|Number} attributes Either a model's id, or the attributes used to create or update a model.
* @param {Object} [options]
* @param {Boolean} [options.merge=true]
* @param {Boolean} [options.parse=false]
* @return {Backbone.RelationalModel}
*/
find: function( attributes, options ) {
options || ( options = {} );
options.create = false;
return this.findOrCreate( attributes, options );
},
/**
* A hook to override the matching when updating (or creating) a model.
* The default implementation is to look up the model by id in the store.
* @param {Object} attributes
* @returns {Backbone.RelationalModel}
*/
findModel: function( attributes ) {
return Backbone.Relational.store.find( this, attributes );
}
});
_.extend( Backbone.RelationalModel.prototype, Backbone.Semaphore );
/**
* Override Backbone.Collection._prepareModel, so objects will be built using the correct type
* if the collection.model has subModels.
* Attempts to find a model for `attrs` in Backbone.store through `findOrCreate`
* (which sets the new properties on it if found), or instantiates a new model.
*/
Backbone.Collection.prototype.__prepareModel = Backbone.Collection.prototype._prepareModel;
Backbone.Collection.prototype._prepareModel = function( attrs, options ) {
var model;
if ( attrs instanceof Backbone.Model ) {
if ( !attrs.collection ) {
attrs.collection = this;
}
model = attrs;
}
else {
options = options ? _.clone( options ) : {};
options.collection = this;
if ( typeof this.model.findOrCreate !== 'undefined' ) {
model = this.model.findOrCreate( attrs, options );
}
else {
model = new this.model( attrs, options );
}
if ( model && model.validationError ) {
this.trigger( 'invalid', this, attrs, options );
model = false;
}
}
return model;
};
/**
* Override Backbone.Collection.set, so we'll create objects from attributes where required,
* and update the existing models. Also, trigger 'relational:add'.
*/
var set = Backbone.Collection.prototype.__set = Backbone.Collection.prototype.set;
Backbone.Collection.prototype.set = function( models, options ) {
// Short-circuit if this Collection doesn't hold RelationalModels
if ( !( this.model.prototype instanceof Backbone.RelationalModel ) ) {
return set.call( this, models, options );
}
if ( options && options.parse ) {
models = this.parse( models, options );
}
var singular = !_.isArray( models ),
newModels = [],
toAdd = [],
model = null;
models = singular ? ( models ? [ models ] : [] ) : _.clone( models );
//console.debug( 'calling add on coll=%o; model=%o, options=%o', this, models, options );
for ( var i = 0; i < models.length; i++ ) {
model = models[i];
if ( !( model instanceof Backbone.Model ) ) {
model = Backbone.Collection.prototype._prepareModel.call( this, model, options );
}
if ( model ) {
toAdd.push( model );
if ( !( this.get( model ) || this.get( model.cid ) ) ) {
newModels.push( model );
}
// If we arrive in `add` while performing a `set` (after a create, so the model gains an `id`),
// we may get here before `_onModelEvent` has had the chance to update `_byId`.
else if ( model.id !== null && model.id !== undefined ) {
this._byId[ model.id ] = model;
}
}
}
// Add 'models' in a single batch, so the original add will only be called once (and thus 'sort', etc).
// If `parse` was specified, the collection and contained models have been parsed now.
toAdd = singular ? ( toAdd.length ? toAdd[ 0 ] : null ) : toAdd;
var result = set.call( this, toAdd, _.defaults( { merge: false, parse: false }, options ) );
for ( i = 0; i < newModels.length; i++ ) {
model = newModels[i];
// Fire a `relational:add` event for any model in `newModels` that has actually been added to the collection.
if ( this.get( model ) || this.get( model.cid ) ) {
this.trigger( 'relational:add', model, this, options );
}
}
return result;
};
/**
* Override 'Backbone.Collection._removeModels' to trigger 'relational:remove'.
*/
var _removeModels = Backbone.Collection.prototype.___removeModels = Backbone.Collection.prototype._removeModels;
Backbone.Collection.prototype._removeModels = function( models, options ) {
// Short-circuit if this Collection doesn't hold RelationalModels
if ( !( this.model.prototype instanceof Backbone.RelationalModel ) ) {
return _removeModels.call( this, models, options );
}
var toRemove = [];
//console.debug('calling remove on coll=%o; models=%o, options=%o', this, models, options );
_.each( models, function( model ) {
model = this.get( model ) || ( model && this.get( model.cid ) );
model && toRemove.push( model );
}, this );
var result = _removeModels.call( this, toRemove, options );
_.each( toRemove, function( model ) {
this.trigger( 'relational:remove', model, this, options );
}, this );
return result;
};
/**
* Override 'Backbone.Collection.reset' to trigger 'relational:reset'.
*/
var reset = Backbone.Collection.prototype.__reset = Backbone.Collection.prototype.reset;
Backbone.Collection.prototype.reset = function( models, options ) {
options = _.extend( { merge: true }, options );
var result = reset.call( this, models, options );
if ( this.model.prototype instanceof Backbone.RelationalModel ) {
this.trigger( 'relational:reset', this, options );
}
return result;
};
/**
* Override 'Backbone.Collection.sort' to trigger 'relational:reset'.
*/
var sort = Backbone.Collection.prototype.__sort = Backbone.Collection.prototype.sort;
Backbone.Collection.prototype.sort = function( options ) {
var result = sort.call( this, options );
if ( this.model.prototype instanceof Backbone.RelationalModel ) {
this.trigger( 'relational:reset', this, options );
}
return result;
};
/**
* Override 'Backbone.Collection.trigger' so 'add', 'remove' and 'reset' events are queued until relations
* are ready.
*/
var trigger = Backbone.Collection.prototype.__trigger = Backbone.Collection.prototype.trigger;
Backbone.Collection.prototype.trigger = function( eventName ) {
// Short-circuit if this Collection doesn't hold RelationalModels
if ( !( this.model.prototype instanceof Backbone.RelationalModel ) ) {
return trigger.apply( this, arguments );
}
if ( eventName === 'add' || eventName === 'remove' || eventName === 'reset' || eventName === 'sort' ) {
var dit = this,
args = arguments;
if ( _.isObject( args[ 3 ] ) ) {
args = _.toArray( args );
// the fourth argument is the option object.
// we need to clone it, as it could be modified while we wait on the eventQueue to be unblocked
args[ 3 ] = _.clone( args[ 3 ] );
}
Backbone.Relational.eventQueue.add( function() {
trigger.apply( dit, args );
});
}
else {
trigger.apply( this, arguments );
}
return this;
};
// Override .extend() to automatically call .setup()
Backbone.RelationalModel.extend = function( protoProps, classProps ) {
var child = Backbone.Model.extend.call( this, protoProps, classProps );
child.setup( this );
return child;
};
}));