/**
* Backbone-relational.js 0.6.0
* (c) 2011 Paul Uithol
*
* 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.
*/
( function( undefined ) {
"use strict";
/**
* CommonJS shim
**/
var _, Backbone, exports;
if ( typeof window === 'undefined' ) {
_ = require( 'underscore' );
Backbone = require( 'backbone' );
exports = module.exports = Backbone;
}
else {
_ = window._;
Backbone = window.Backbone;
exports = window;
}
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();
}
},
process: function() {
while ( this._queue && this._queue.length ) {
this._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 'update:<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._subModels = [];
this._modelScopes = [ exports ];
};
_.extend( Backbone.Store.prototype, Backbone.Events, {
addModelScope: function( scope ) {
this._modelScopes.push( 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 _.find( 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 );
}, 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 );
var addRelation = function( model, relation ) {
if ( !model.prototype.relations ) {
model.prototype.relations = [];
}
model.prototype.relations.push( relation );
_.each( model._subModels, function( subModel ) {
addRelation( subModel, relation );
}, this );
};
addRelation( relation.model, relation );
this.retroFitRelation( relation );
}
},
/**
* 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 );
coll.each( function( model ) {
if ( !( model instanceof relation.model ) ) {
return;
}
new relation.type( model, relation );
}, this);
},
/**
* Find the Store's collection for a certain type of model.
* @param {Backbone.RelationalModel} model
* @return {Backbone.Collection} A collection if found (or applicable for 'model'), or null
*/
getCollection: function( model ) {
if ( model instanceof Backbone.RelationalModel ) {
model = model.constructor;
}
var rootModel = model;
while ( rootModel._superModel ) {
rootModel = rootModel._superModel;
}
var coll = _.detect( this._collections, function( c ) {
return c.model === rootModel;
});
if ( !coll ) {
coll = this._createCollection( rootModel );
}
return coll;
},
/**
* Find a type on the global object by name. Splits name 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[ val ];
}, 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;
},
/**
*
* @param type
* @param {String|Number|Object|Backbone.RelationalModel} item
*/
find: function( type, item ) {
var id = this.resolveIdForItem( type, item );
var 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 it's appropriate collection. Retain the original contents of 'model.collection'.
* @param {Backbone.RelationalModel} model
*/
register: function( model ) {
var coll = this.getCollection( model );
if ( coll ) {
if ( coll.get( model ) ) {
throw new Error( "Cannot instantiate more than one Backbone.RelationalModel with the same id per type!" );
}
var modelColl = model.collection;
coll.add( model );
model.bind( 'destroy', this.unregister, this );
model.collection = modelColl;
}
},
/**
* Explicitly update a model's id in it's store collection
* @param {Backbone.RelationalModel} model
*/
update: function( model ) {
var coll = this.getCollection( model );
coll._onModelEvent( 'change:' + model.idAttribute, model, coll );
},
/**
* Remove a 'model' from the store.
* @param {Backbone.RelationalModel} model
*/
unregister: function( model ) {
model.unbind( 'destroy', this.unregister );
var coll = this.getCollection( model );
coll && coll.remove( model );
}
});
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
* @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').
*/
Backbone.Relation = function( instance, options ) {
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.reverseRelation.type = !_.isString( this.reverseRelation.type ) ? this.reverseRelation.type :
Backbone[ this.reverseRelation.type ] || Backbone.Relational.store.getObjectByName( this.reverseRelation.type );
this.model = options.model || this.instance.constructor;
this.options = _.defaults( options, this.options, Backbone.Relation.prototype.options );
this.key = this.options.key;
this.keySource = this.options.keySource || this.key;
this.keyDestination = this.options.keyDestination || this.keySource || this.key;
// 'exports' should be the global object where 'relatedModel' can be found on if given as a string.
this.relatedModel = this.options.relatedModel;
if ( _.isString( this.relatedModel ) ) {
this.relatedModel = Backbone.Relational.store.getObjectByName( this.relatedModel );
}
if ( !this.checkPreconditions() ) {
return false;
}
if ( instance ) {
this.keyContents = this.instance.get( this.keySource );
// Explicitly clear 'keySource', to prevent a leaky abstraction if 'keySource' differs from 'key'.
if ( this.key !== this.keySource ) {
this.instance.unset( this.keySource, { silent: true } );
}
// Add this Relation to instance._relations
this.instance._relations.push( this );
}
// 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 it's own reverseRelation
},
this.reverseRelation // Take further properties from this.reverseRelation (type, key, etc.)
) );
}
_.bindAll( this, '_modelRemovedFromCollection', '_relatedModelAdded', '_relatedModelRemoved' );
if ( instance ) {
this.initialize();
// When a model in the store is destroyed, check if it is 'this.instance'.
Backbone.Relational.store.getCollection( this.instance )
.bind( 'relational:remove', this._modelRemovedFromCollection );
// When 'relatedModel' are created or destroyed, check if it affects this relation.
Backbone.Relational.store.getCollection( this.relatedModel )
.bind( 'relational:add', this._relatedModelAdded )
.bind( 'relational:remove', this._relatedModelRemoved );
}
};
// 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
},
instance: null,
key: null,
keyContents: null,
relatedModel: null,
reverseRelation: null,
related: null,
_relatedModelAdded: function( model, coll, options ) {
// Allow 'model' to set up it's relations, before calling 'tryAddRelated'
// (which can result in a call to 'addRelated' on a relation of 'model')
var dit = this;
model.queue( function() {
dit.tryAddRelated( model, options );
});
},
_relatedModelRemoved: function( model, coll, options ) {
this.removeRelated( model, options );
},
_modelRemovedFromCollection: function( model ) {
if ( model === this.instance ) {
this.destroy();
}
},
/**
* 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; no 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 duplicate relationship
if ( i && i._relations.length ) {
var exists = _.any( i._relations, function( rel ) {
var hasReverseRelation = this.reverseRelation.key && rel.reverseRelation.key;
return rel.relatedModel === rm && rel.key === k &&
( !hasReverseRelation || this.reverseRelation.key === rel.reverseRelation.key );
}, this );
if ( exists ) {
warn && console.warn( 'Relation=%o between instance=%o.%s and relatedModel=%o.%s already exists',
this, i, k, rm, this.reverseRelation.key );
return false;
}
}
return true;
},
/**
* Set the related model(s) for this relation
* @param {Backbone.Mode|Backbone.Collection} related
* @param {Object} [options]
*/
setRelated: function( related, options ) {
this.related = related;
this.instance.acquire();
this.instance.set( this.key, related, _.defaults( options || {}, { silent: true } ) );
this.instance.release();
},
/**
* 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 ) {
if ( relation.instance instanceof this.relatedModel && this.reverseRelation.key === relation.key &&
this.key === relation.reverseRelation.key ) {
return true;
}
return false;
},
/**
* 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 ] );
_.each( models , function( related ) {
_.each( related.getRelations(), function( relation ) {
if ( this._isReverseRelation( relation ) ) {
reverseRelations.push( relation );
}
}, this );
}, this );
return reverseRelations;
},
/**
* Rename options.silent to options.silentChange, so events propagate properly.
* (for example in HasMany, from 'addRelated'->'handleAddition')
* @param {Object} [options]
* @return {Object}
*/
sanitizeOptions: function( options ) {
options = options ? _.clone( options ) : {};
if ( options.silent ) {
options.silentChange = true;
delete options.silent;
}
return options;
},
/**
* Rename options.silentChange to options.silent, so events are silenced as intended in Backbone's
* original functions.
* @param {Object} [options]
* @return {Object}
*/
unsanitizeOptions: function( options ) {
options = options ? _.clone( options ) : {};
if ( options.silentChange ) {
options.silent = true;
delete options.silentChange;
}
return options;
},
// Cleanup. Get reverse relation, call removeRelated on each.
destroy: function() {
Backbone.Relational.store.getCollection( this.instance )
.unbind( 'relational:remove', this._modelRemovedFromCollection );
Backbone.Relational.store.getCollection( this.relatedModel )
.unbind( 'relational:add', this._relatedModelAdded )
.unbind( 'relational:remove', this._relatedModelRemoved );
_.each( this.getReverseRelations(), function( relation ) {
relation.removeRelated( this.instance );
}, this );
}
});
Backbone.HasOne = Backbone.Relation.extend({
options: {
reverseRelation: { type: 'HasMany' }
},
initialize: function() {
_.bindAll( this, 'onChange' );
this.instance.bind( 'relational:change:' + this.key, this.onChange );
var model = this.findRelated( { silent: true } );
this.setRelated( model );
// Notify new 'related' object of the new relation.
_.each( this.getReverseRelations(), function( relation ) {
relation.addRelated( this.instance );
}, this );
},
findRelated: function( options ) {
var item = this.keyContents;
var model = null;
if ( item instanceof this.relatedModel ) {
model = item;
}
else if ( item || item === 0 ) { // since 0 can be a valid `id` as well
model = this.relatedModel.findOrCreate( item, { create: this.options.createModels } );
}
return model;
},
/**
* 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 = this.sanitizeOptions( 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 );
var oldRelated = changed ? this.related : options._related;
if ( changed ) {
this.keyContents = attr;
// Set new 'related'
if ( attr instanceof this.relatedModel ) {
this.related = attr;
}
else if ( attr ) {
var related = this.findRelated( options );
this.setRelated( related );
}
else {
this.setRelated( null );
}
}
// Notify old 'related' object of the terminated relation
if ( oldRelated && this.related !== oldRelated ) {
_.each( this.getReverseRelations( oldRelated ), function( relation ) {
relation.removeRelated( this.instance, 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 'update:<key>' event if 'related' was updated
if ( !options.silentChange && this.related !== oldRelated ) {
var dit = this;
Backbone.Relational.eventQueue.add( function() {
dit.instance.trigger( 'update:' + dit.key, dit.instance, dit.related, options );
});
}
this.release();
},
/**
* If a new 'this.relatedModel' appears in the 'store', try to match it to the last set 'keyContents'
*/
tryAddRelated: function( model, options ) {
if ( this.related ) {
return;
}
options = this.sanitizeOptions( options );
var item = this.keyContents;
if ( item || item === 0 ) { // since 0 can be a valid `id` as well
var id = Backbone.Relational.store.resolveIdForItem( this.relatedModel, item );
if ( !_.isNull( id ) && model.id === id ) {
this.addRelated( model, options );
}
}
},
addRelated: function( model, options ) {
if ( model !== this.related ) {
var oldRelated = this.related || null;
this.setRelated( model );
this.onChange( this.instance, model, { _related: oldRelated } );
}
},
removeRelated: function( model, options ) {
if ( !this.related ) {
return;
}
if ( model === this.related ) {
var oldRelated = this.related || null;
this.setRelated( null );
this.onChange( this.instance, model, { _related: oldRelated } );
}
}
});
Backbone.HasMany = Backbone.Relation.extend({
collectionType: null,
options: {
reverseRelation: { type: 'HasOne' },
collectionType: Backbone.Collection,
collectionKey: true,
collectionOptions: {}
},
initialize: function() {
_.bindAll( this, 'onChange', 'handleAddition', 'handleRemoval', 'handleReset' );
this.instance.bind( 'relational:change:' + this.key, this.onChange );
// Handle a custom 'collectionType'
this.collectionType = this.options.collectionType;
if ( _.isString( this.collectionType ) ) {
this.collectionType = Backbone.Relational.store.getObjectByName( this.collectionType );
}
if ( !this.collectionType.prototype instanceof Backbone.Collection ){
throw new Error( 'collectionType must inherit from Backbone.Collection' );
}
// Handle cases where a model/relation is created with a collection passed straight into 'attributes'
if ( this.keyContents instanceof Backbone.Collection ) {
this.setRelated( this._prepareCollection( this.keyContents ) );
}
else {
this.setRelated( this._prepareCollection() );
}
this.findRelated( { silent: true } );
},
_getCollectionOptions: function() {
return _.isFunction( this.options.collectionOptions ) ?
this.options.collectionOptions( this.instance ) :
this.options.collectionOptions;
},
/**
* 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]
*/
_prepareCollection: function( collection ) {
if ( this.related ) {
this.related
.unbind( 'relational:add', this.handleAddition )
.unbind( 'relational:remove', this.handleRemoval )
.unbind( 'relational:reset', this.handleReset )
}
if ( !collection || !( collection instanceof Backbone.Collection ) ) {
collection = new this.collectionType( [], this._getCollectionOptions() );
}
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;
}
}
collection
.bind( 'relational:add', this.handleAddition )
.bind( 'relational:remove', this.handleRemoval )
.bind( 'relational:reset', this.handleReset );
return collection;
},
findRelated: function( options ) {
if ( this.keyContents ) {
var models = [];
if ( this.keyContents instanceof Backbone.Collection ) {
models = this.keyContents.models;
}
else {
// Handle cases the an API/user supplies just an Object/id instead of an Array
this.keyContents = _.isArray( this.keyContents ) ? this.keyContents : [ this.keyContents ];
// Try to find instances of the appropriate 'relatedModel' in the store
_.each( this.keyContents, function( item ) {
var model = null;
if ( item instanceof this.relatedModel ) {
model = item;
}
else if ( item || item === 0 ) { // since 0 can be a valid `id` as well
model = this.relatedModel.findOrCreate( item, { create: this.options.createModels } );
}
if ( model && !this.related.getByCid( model ) && !this.related.get( model ) ) {
models.push( model );
}
}, this );
}
// Add all found 'models' in on go, so 'add' will only be called once (and thus 'sort', etc.)
if ( models.length ) {
options = this.unsanitizeOptions( options );
this.related.add( models, options );
}
}
},
/**
* If the key is changed, notify old & new reverse relations and initialize the new relation
*/
onChange: function( model, attr, options ) {
options = this.sanitizeOptions( options );
this.keyContents = attr;
// Notify old 'related' object of the terminated relation
_.each( this.getReverseRelations(), function( relation ) {
relation.removeRelated( this.instance, options );
}, this );
// Replace 'this.related' by 'attr' if it is a Backbone.Collection
if ( attr instanceof Backbone.Collection ) {
this._prepareCollection( attr );
this.related = attr;
}
// Otherwise, 'attr' should be an array of related object ids.
// Re-use the current 'this.related' if it is a Backbone.Collection, and remove any current entries.
// Otherwise, create a new collection.
else {
var coll;
if ( this.related instanceof Backbone.Collection ) {
coll = this.related;
coll.remove( coll.models );
}
else {
coll = this._prepareCollection();
}
this.setRelated( coll );
this.findRelated( options );
}
// Notify new 'related' object of the new relation
_.each( this.getReverseRelations(), function( relation ) {
relation.addRelated( this.instance, options );
}, this );
var dit = this;
Backbone.Relational.eventQueue.add( function() {
!options.silentChange && dit.instance.trigger( 'update:' + dit.key, dit.instance, dit.related, options );
});
},
tryAddRelated: function( model, options ) {
options = this.sanitizeOptions( options );
if ( !this.related.getByCid( model ) && !this.related.get( model ) ) {
// Check if this new model was specified in 'this.keyContents'
var item = _.any( this.keyContents, function( item ) {
var id = Backbone.Relational.store.resolveIdForItem( this.relatedModel, item );
return !_.isNull( id ) && id === model.id;
}, this );
if ( item ) {
this.related.add( model, options );
}
}
},
/**
* 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);
// Make sure the model is in fact a valid model before continuing.
// (it can be invalid as a result of failing validation in Backbone.Collection._prepareModel)
if ( !( model instanceof Backbone.Model ) ) {
return;
}
options = this.sanitizeOptions( options );
_.each( this.getReverseRelations( model ), function( relation ) {
relation.addRelated( this.instance, options );
}, this );
// Only trigger 'add' once the newly added model is initialized (so, has it's relations set up)
var dit = this;
Backbone.Relational.eventQueue.add( function() {
!options.silentChange && 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);
if ( !( model instanceof Backbone.Model ) ) {
return;
}
options = this.sanitizeOptions( options );
_.each( this.getReverseRelations( model ), function( relation ) {
relation.removeRelated( this.instance, options );
}, this );
var dit = this;
Backbone.Relational.eventQueue.add( function() {
!options.silentChange && dit.instance.trigger( 'remove:' + dit.key, model, dit.related, options );
});
},
handleReset: function( coll, options ) {
options = this.sanitizeOptions( options );
var dit = this;
Backbone.Relational.eventQueue.add( function() {
!options.silentChange && dit.instance.trigger( 'reset:' + dit.key, dit.related, options );
});
},
addRelated: function( model, options ) {
var dit = this;
options = this.unsanitizeOptions( options );
model.queue( function() { // Queued to avoid errors for adding 'model' to the 'this.related' set twice
if ( dit.related && !dit.related.getByCid( model ) && !dit.related.get( model ) ) {
dit.related.add( model, options );
}
});
},
removeRelated: function( model, options ) {
options = this.unsanitizeOptions( options );
if ( this.related.getByCid( model ) || 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)
* - 'update:<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,
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:
// a) Survive 'Backbone.Collection.add'; this takes care we won't error on "can't add model to a set twice"
// (by creating a model from properties, having the model add itself to the collection via one of
// it's relations, then trying to add it to the collection).
// b) Trigger 'HasMany' collection events only after the model is really fully set up.
// Example that triggers both a and b: "p.get('jobs').add( { company: c, person: p } )".
var dit = this;
if ( options && options.collection ) {
this._deferProcessing = true;
var processQueue = function( model ) {
if ( model === dit ) {
dit._deferProcessing = false;
dit.processQueue();
options.collection.unbind( 'relational:add', processQueue );
}
};
options.collection.bind( 'relational:add', processQueue );
// So we do process the queue eventually, regardless of whether this model really gets added to 'options.collection'.
_.defer( function() {
processQueue( dit );
});
}
this._queue = new Backbone.BlockingQueue();
this._queue.block();
Backbone.Relational.eventQueue.block();
Backbone.Model.apply( this, arguments );
// 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 && 'change' === eventName.substr( 0, 6 ) ) {
var dit = this, args = arguments;
Backbone.Relational.eventQueue.add( function() {
Backbone.Model.prototype.trigger.apply( dit, args );
});
}
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() {
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 ) {
var type = !_.isString( rel.type ) ? rel.type : Backbone[ rel.type ] || Backbone.Relational.store.getObjectByName( rel.type );
if ( type && type.prototype instanceof Backbone.Relation ) {
new type( this, rel ); // Also pushes the new Relation into _relations
}
else {
Backbone.Relational.showWarnings && typeof console !== 'undefined' && console.warn( 'Relation=%o; missing or invalid type!', rel );
}
}, this );
this._isInitialized = true;
this.release();
this.processQueue();
},
/**
* When new values are set, notify this model's relations (also if options.silent is set).
* (Relation.setRelated locks this model before calling 'set' on it to prevent loops)
*/
updateRelations: function( options ) {
if ( this._isInitialized && !this.isLocked() ) {
_.each( this._relations, function( rel ) {
// Update from data in `rel.keySource` if set, or `rel.key` otherwise
var val = this.attributes[ rel.keySource ] || this.attributes[ rel.key ];
if ( rel.related !== val ) {
this.trigger( 'relational:change:' + rel.key, this, val, options || {} );
}
}, 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 key {string} The relation key to look for.
* @return {Backbone.Relation} An instance of 'Backbone.Relation', if a relation was found for 'key', or null.
*/
getRelation: function( key ) {
return _.detect( this._relations, function( rel ) {
if ( rel.key === key ) {
return true;
}
}, this );
},
/**
* Get all of the created relations.
* @return {Backbone.Relation[]}
*/
getRelations: function() {
return this._relations;
},
/**
* Retrieve related objects.
* @param key {string} The relation key to fetch models for.
* @param [options] {Object} Options for 'Backbone.Model.fetch' and 'Backbone.sync'.
* @param [update=false] {boolean} Whether to force a fetch from the server (updating existing models).
* @return {jQuery.when[]} An array of request objects
*/
fetchRelated: function( key, options, update ) {
options || ( options = {} );
var setUrl,
requests = [],
rel = this.getRelation( key ),
keyContents = rel && rel.keyContents,
toFetch = keyContents && _.select( _.isArray( keyContents ) ? keyContents : [ keyContents ], function( item ) {
var id = Backbone.Relational.store.resolveIdForItem( rel.relatedModel, item );
return !_.isNull( id ) && ( update || !Backbone.Relational.store.find( rel.relatedModel, id ) );
}, this );
if ( toFetch && toFetch.length ) {
// Create a model for each entry in 'keyContents' that is to be fetched
var models = _.map( toFetch, function( item ) {
var model;
if ( _.isObject( item ) ) {
model = rel.relatedModel.build( item );
}
else {
var attrs = {};
attrs[ rel.relatedModel.prototype.idAttribute ] = item;
model = rel.relatedModel.build( attrs );
}
return model;
}, this );
// Try if the 'collection' can provide a url to fetch a set of models in one request.
if ( rel.related instanceof Backbone.Collection && _.isFunction( rel.related.url ) ) {
setUrl = rel.related.url( models );
}
// An assumption is 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 ( setUrl && setUrl !== rel.related.url() ) {
var opts = _.defaults(
{
error: function() {
var args = arguments;
_.each( models, function( model ) {
model.trigger( 'destroy', model, model.collection, options );
options.error && options.error.apply( model, args );
});
},
url: setUrl
},
options,
{ add: true }
);
requests = [ rel.related.fetch( opts ) ];
}
else {
requests = _.map( models, function( model ) {
var opts = _.defaults(
{
error: function() {
model.trigger( 'destroy', model, model.collection, options );
options.error && options.error.apply( model, arguments );
}
},
options
);
return model.fetch( opts );
}, this );
}
}
return requests;
},
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;
if ( _.isObject( key ) || key == null ) {
attributes = key;
options = value;
}
else {
attributes = {};
attributes[ key ] = value;
}
var result = Backbone.Model.prototype.set.apply( this, arguments );
// Ideal place to set up relations :)
if ( !this._isInitialized && !this.isLocked() ) {
this.constructor.initializeModelHierarchy();
Backbone.Relational.store.register( this );
this.initializeRelations();
}
// Update the 'idAttribute' in Backbone.store if; we don't want it to miss an 'id' update due to {silent:true}
else if ( attributes && this.idAttribute in attributes ) {
Backbone.Relational.store.update( this );
}
if ( attributes ) {
this.updateRelations( options );
}
// Try to run the global queue holding external events
Backbone.Relational.eventQueue.unblock();
return result;
},
unset: function( attribute, options ) {
Backbone.Relational.eventQueue.block();
var result = Backbone.Model.prototype.unset.apply( this, arguments );
this.updateRelations( options );
// Try to run the global queue holding external events
Backbone.Relational.eventQueue.unblock();
return result;
},
clear: function( options ) {
Backbone.Relational.eventQueue.block();
var result = Backbone.Model.prototype.clear.apply( this, arguments );
this.updateRelations( options );
// Try to run the global queue holding external events
Backbone.Relational.eventQueue.unblock();
return result;
},
/**
* Override 'change', so the change will only execute after 'set' has finised (relations are updated),
* and 'previousAttributes' will be available when the event is fired.
*/
change: function( options ) {
var dit = this, args = arguments;
Backbone.Relational.eventQueue.add( function() {
Backbone.Model.prototype.change.apply( dit, args );
});
},
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() {
// 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 );
if ( this.constructor._superModel && !( this.constructor._subModelTypeAttribute in json ) ) {
json[ this.constructor._subModelTypeAttribute ] = this.constructor._subModelTypeValue;
}
_.each( this._relations, function( rel ) {
var value = json[ rel.key ];
if ( rel.options.includeInJSON === true) {
if ( value && _.isFunction( value.toJSON ) ) {
json[ rel.keyDestination ] = value.toJSON();
}
else {
json[ rel.keyDestination ] = null;
}
}
else if ( _.isString( rel.options.includeInJSON ) ) {
if ( value instanceof Backbone.Collection ) {
json[ rel.keyDestination ] = value.pluck( rel.options.includeInJSON );
}
else if ( value instanceof Backbone.Model ) {
json[ rel.keyDestination ] = value.get( rel.options.includeInJSON );
}
else {
json[ rel.keyDestination ] = null;
}
}
else if ( _.isArray( rel.options.includeInJSON ) ) {
if ( value instanceof Backbone.Collection ) {
var valueSub = [];
value.each( function( model ) {
var curJson = {};
_.each( rel.options.includeInJSON, function( key ) {
curJson[ key ] = model.get( key );
});
valueSub.push( curJson );
});
json[ rel.keyDestination ] = valueSub;
}
else if ( value instanceof Backbone.Model ) {
var valueSub = {};
_.each( rel.options.includeInJSON, function( key ) {
valueSub[ key ] = value.get( key );
});
json[ rel.keyDestination ] = valueSub;
}
else {
json[ rel.keyDestination ] = null;
}
}
else {
delete json[ rel.key ];
}
if ( rel.keyDestination !== rel.key ) {
delete json[ rel.key ];
}
});
this.release();
return json;
}
},
{
setup: function( superModel ) {
// We don't want to share a relations array with a parent, as this will cause problems with
// reverse relations.
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 never gets defined, e.g. a typo
* 2. it is related to itself
* In neither of these cases do we need to pre-initialize reverse relations.
*/
var relatedModel = Backbone.Relational.store.getObjectByName( rel.relatedModel );
preInitialize = relatedModel && ( relatedModel.prototype instanceof Backbone.RelationalModel );
}
var type = !_.isString( rel.type ) ? rel.type : Backbone[ rel.type ] || Backbone.Relational.store.getObjectByName( rel.type );
if ( preInitialize && type && type.prototype instanceof Backbone.Relation ) {
new type( null, 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 ) {
var model = this;
// '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.
// Lookup the proper subModelType in 'this._subModels'.
if ( this._subModels && this.prototype.subModelTypeAttribute in attributes ) {
var subModelTypeAttribute = attributes[ this.prototype.subModelTypeAttribute ];
var subModelType = this._subModels[ subModelTypeAttribute ];
if ( subModelType ) {
model = subModelType;
}
}
return new model( attributes, options );
},
initializeModelHierarchy: function() {
// If we're here for the first time, try to determine if this modelType has a 'superModel'.
if ( _.isUndefined( this._superModel ) || _.isNull( this._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').
// 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.
if ( this._superModel ) {
//
if ( this._superModel.prototype.relations ) {
var supermodelRelationsExist = _.any( this.prototype.relations, function( rel ) {
return rel.model && rel.model !== this;
}, this );
if ( !supermodelRelationsExist ) {
this.prototype.relations = this._superModel.prototype.relations.concat( this.prototype.relations );
}
}
}
else {
this._superModel = false;
}
}
// If we came here through 'build' for a model that has 'subModelTypes', and not all of them have been resolved yet, try to resolve each.
if ( this.prototype.subModelTypes && _.keys( this.prototype.subModelTypes ).length !== _.keys( this._subModels ).length ) {
_.each( this.prototype.subModelTypes, function( subModelTypeName ) {
var subModelType = Backbone.Relational.store.getObjectByName( subModelTypeName );
subModelType && subModelType.initializeModelHierarchy();
});
}
},
/**
* Find an instance of `this` type in 'Backbone.Relational.store'.
* - If `attributes` is a string or a number, `findOrCreate` will just query the `store` and return a model if found.
* - If `attributes` is an object, the model will be updated with `attributes` if found.
* Otherwise, a new model is created with `attributes` (unless `options.create` is explicitly set to `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]
* @return {Backbone.RelationalModel}
*/
findOrCreate: function( attributes, options ) {
// Try to find an instance of 'this' model type in the store
var model = Backbone.Relational.store.find( this, attributes );
// If we found an instance, update it with the data in 'item'; if not, create an instance
// (unless 'options.create' is false).
if ( _.isObject( attributes ) ) {
if ( model ) {
model.set( model.parse ? model.parse( attributes ) : attributes, options );
}
else if ( !options || ( options && options.create !== false ) ) {
model = this.build( attributes, options );
}
}
return model;
}
});
_.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.
*/
Backbone.Collection.prototype.__prepareModel = Backbone.Collection.prototype._prepareModel;
Backbone.Collection.prototype._prepareModel = function ( model, options ) {
options || (options = {});
if ( !( model instanceof Backbone.Model ) ) {
var attrs = model;
options.collection = this;
if ( typeof this.model.findOrCreate !== 'undefined' ) {
model = this.model.findOrCreate( attrs, options );
}
else {
model = new this.model( attrs, options );
}
if ( !model._validate( model.attributes, options ) ) {
model = false;
}
}
else if ( !model.collection ) {
model.collection = this;
}
return model;
}
/**
* Override Backbone.Collection.add, so objects fetched from the server multiple times will
* update the existing Model. Also, trigger 'relational:add'.
*/
var add = Backbone.Collection.prototype.__add = Backbone.Collection.prototype.add;
Backbone.Collection.prototype.add = function( models, options ) {
options || (options = {});
if ( !_.isArray( models ) ) {
models = [ models ];
}
var modelsToAdd = [];
//console.debug( 'calling add on coll=%o; model=%o, options=%o', this, models, options );
_.each( models, function( model ) {
if ( !( model instanceof Backbone.Model ) ) {
// `_prepareModel` attempts to find `model` in Backbone.store through `findOrCreate`,
// and sets the new properties on it if is found. Otherwise, a new model is instantiated.
model = Backbone.Collection.prototype._prepareModel.call( this, model, options );
}
if ( model instanceof Backbone.Model && !this.get( model ) && !this.getByCid( model ) ) {
modelsToAdd.push( model );
}
}, this );
// Add 'models' in a single batch, so the original add will only be called once (and thus 'sort', etc).
if ( modelsToAdd.length ) {
add.call( this, modelsToAdd, options );
_.each( modelsToAdd, function( model ) {
this.trigger( 'relational:add', model, this, options );
}, this );
}
return this;
};
/**
* Override 'Backbone.Collection.remove' to trigger 'relational:remove'.
*/
var remove = Backbone.Collection.prototype.__remove = Backbone.Collection.prototype.remove;
Backbone.Collection.prototype.remove = function( models, options ) {
options || (options = {});
if ( !_.isArray( models ) ) {
models = [ models ];
}
else {
models = models.slice( 0 );
}
//console.debug('calling remove on coll=%o; models=%o, options=%o', this, models, options );
_.each( models, function( model ) {
model = this.getByCid( model ) || this.get( model );
if ( model instanceof Backbone.Model ) {
remove.call( this, model, options );
this.trigger('relational:remove', model, this, options);
}
}, this );
return this;
};
/**
* 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 ) {
reset.call( this, models, options );
this.trigger( 'relational:reset', this, options );
return this;
};
/**
* Override 'Backbone.Collection.sort' to trigger 'relational:reset'.
*/
var sort = Backbone.Collection.prototype.__sort = Backbone.Collection.prototype.sort;
Backbone.Collection.prototype.sort = function( options ) {
sort.call( this, options );
this.trigger( 'relational:reset', this, options );
return this;
};
/**
* 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 ) {
if ( eventName === 'add' || eventName === 'remove' || eventName === 'reset' ) {
var dit = this, args = arguments;
if (eventName === 'add') {
args = _.toArray(args);
// the fourth argument in case of a regular add is the option object.
// we need to clone it, as it could be modified while we wait on the eventQueue to be unblocked
if (_.isObject(args[3])) {
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.apply( this, arguments );
child.setup( this );
return child;
};
})();