promised-models2
v1.1.4
Published
promise based, typed attributes, nested models and collections
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Readme
Promised Models 2
Key features
- promise based
- typed attributes
- nested models and collections
- async calculations and validation
Install
$npm install --save promised-models2
Usage
var Model = require('promises-models'),
FashionModel = new Model.inherit({
attributes: {
name: Model.attributeTypes.String
}
}),
model = new FashionModel({
name: 'Kate'
});
model.get('name'); // 'Kate'
Api reference (in progress)
Model sync methods
inherit Model.inherit(properties, [classPorperties])
Creates you own model class by extending Model
. You can define attributes, instance/class method and properties. Inheritance is built over inherit.
var CountedModels = Model.inherit({
__constructor: function () {
this.__base.apply(this, arguments); //super
this.attributes.index.set(this.__self._count); //static properties
this.__self._count ++;
},
getIndex: function () {
return this.get('index');
}
}, {
_count: 0,
getCount: function () {
return this._count;
}
});
attributeTypes Model.attributeTypes
Namespace for predefined types of attributes. Supported types:
Id
- for entity idString
Number
Boolean
List
— for storing arraysModel
— for nested modelsModelsList
— for nested collectionsCollection
- another implementation of collectionsObject
— serializable objects
You can extend default attribute types or create your own
var DateAttribute = Model.attributeTypes.Number.inherit({
//..
}),
FashionModel = Model.inherit({
attributes: {
name: Model.attributeTypes.String,
birthDate: DateAttribute
}
});
Note: models.attributes
will be replaced in constructor with attribute instances.
var model = new FashionModel();
model.attributes.birthDate instanceof DateAttribute; //true
set model.set(attributeName, value)
Set current value of attribute.
var model = new FashionModel();
model.set('name', 'Kate');
model.attributes.name.set('Kate');
model.set({
name: 'Kate',
birthDate: new Date(1974, 1, 16)
});
Note: setting null
is equivalent to call .unset()
get model.get(attributeName)
Get current value of attribute.
var model = new FashionModel({
name: 'Kate',
birthDate: new Date(1974, 1, 16)
})
model.get('name'); //Kate
model.attributes.name.get(); //Kate
model.get('some'); //throws error as unknown attribute
toJSON model.toJSON()
Return shallow copy of model data.
Note: You can create internal attributes, which wouldn't be included to returned object.
var FashionModel = Model.inherit({
attributes: {
name: Model.attributeTypes.String.inherit({
internal: true;
}),
sename: Model.attributeTypes.String.inherit({
internal: true;
}),
fullName: Model.attributeTypes.String
}
}),
model = new FashionModel({
name: 'Kate',
surname: 'Moss',
fullName: 'Kate Moss'
});
model.toJSON(); // {fullName: 'Kate Moss'}
model.get('name'); // Kate
Note: Returned object supposed to be serializable via JSON.parse()
. Due to this reason NaN
and Infinity
are serialized in this way:
NaN -> null
Infinity -> 'Infinity'
getId model.getId()
Returns entity id. You can declare special id attribute, which will be interpreted as entity id. If id attribute is not declared, getId returns null
var FashionModel = Model.inherit({
attributes: {
myId: Model.attributeTypes.Id,
name: Model.attributeTypes.String
}
});
var model = new FashionModel({
myId: 1,
name: 'Kate'
});
model.getId() // 1
FashionModel = Model.inherit({
attributes: {
id: Model.attributeTypes.Id.inherit({
dataType: String
}),
name: Model.attributeTypes.String
}
});
model = new FashionModel({
id: 1,
name: 'Kate'
});
model.getId() // '1'
isChanged model.isChanged([branch])
Has model changed since init or last commit/save/fetch.
var FashionModel = Model.inherit({
attributes: {
name: Model.attributeTypes.String,
weight: Model.attributeTypes.Number.inherit({
default: 50
})
}
}),
model = new FashionModel({
name: 'Kate',
weight: 55
});
model.isChanged(); //false
model.set('weight', 56);
model.isChanged(); //true
commit model.commit([branch])
Cache current model state
var model = new FashionModel();
model.set({
name: 'Kate',
weight: 55
});
model.isChanged();//true
model.commit();
model.isChanged();//false
revert model.revert([branch])
Revert model state to last cashed one
var model = new FashionModel({
name: 'Kate',
weight: 55
});
model.set('weight', 56);
model.revert();
model.get('weight'); //55
model.isChanged(); //false
Note: You can create your own cache by passing branch param.
var RENDERED = 'RENDERED';
model.on('change', function () {
if (model.isChanged(RENDERED)) {
View.render();
model.commit(RENDERED);
}
});
getLastCommitted model.getLastCommitted([branch])
Returns model last cached state.
previous model.previous([attr])
Returns attribute attr
previous value or model previous state if called without arguments.
on model.on([attributes], events, cb, [ctx])
Add event handler for one or multiple model events.
List of events:
change
– some of attributes have been changedchange:attributeName
–attributeName
have been changedcommit
- some of attributes have been committed to default branchbranch:commit
- some of attributes have been committed to branchbranch
commit:attributeName
-attributeName
have been committed to default branchbranch:commit:attributeName
-attributeName
have been committed to branchbranch
destruct
– model was destructedcalculate
– async calculations started
model.on('change', this.changeHandler, this)
.on('change:weight change:name', this.changeHandler, this);
on model.once([attributes], events, cb, [ctx])
Same as model.on
but event handler will be called only once.
un model.un([attributes], events, cb, [ctx])
Unsubscribe event handler from events.
//subscribe
model.on('weight name', 'change', this.changeHandler, this);
//unsubscribe
model.un('change:weight change:name', this.changeHandler, this);
destruct model.destruct()
Remove all events handlers from model and removes model from collections
isSet model.isSet(attributeName)
Returns true
if attribute was set via constructor or set
var model = new FashionModel();
model.isSet('name'); //false
model.set('name', 'Kate');
model.isSet('name'); //true
unset model.unset(attributeName)
Set attribute to default value and model.isSet() === 'false'
var model = new FashionModel();
model.set('name', 'Kate');
model.unset('name');
model.isSet('name'); //false
model.get('name'); //empty string (default value)
Model async methods
validate model.validate()
Validate model attributes.
var FashionModel = Model.inherit({
attributes: {
name: Model.attributeTypes.String.inherit({
validate: function () {
return $.get('/validateName', {
name: this.get()
}).then(function () {
Vow.reject('Value is Invalid!');
});
}
})
}
}),
model = new FashionModel();
model.validate().fail(function (err) {
if (err instanceof Model.ValidationError) {
console.log('Invalid attributes:');
err.attributes.forEach(function (attrErr) {
console.log('Attribute "' + attrErr.attribute.name + '" error:', attrError);
});
} else {
return err;
}
}).done();
Fulfilled attribute validation promise means that attribute is valid, otherwise it's not. Model.ValidationError#attributes
is array of attributes errors (Attribute.ValidationError
).
Note: For Model
and Collection
attributes validation
method is already defined. It validates nested entity and if it's not returns promise rejected with specific error contains nested errors.
If validate
returns promise rejected with String
this string will be used as message for Attribute.ValidationError
. If with something else (besides Boolean
) - rejected value will be available in Attribute.ValidationError#data
.
If attribute can be validated synchronously, you can define getValidationError
method. If it returns non-falsy value, validation promise will be rejected with returned value.
var FashionModel = Model.inherit({
attributes: {
name: Model.attributeTypes.String.inherit({
getValidationError: function () {
if (this.get() !== 'validValue') {
return 'Value is Invalid!';
}
}
})
}
}),
model = new FashionModel();
model.validate().fail(function (err) {
console.log(err.attributes[0]);
});
ready model.ready()
Fulfils when all calculations over model finished.
var FashionModel = Model.inherit({
attributes: {
name: Model.attributeTypes.String,
ratingIndex: Model.attributeTypes.Number.inherit({
calculate: function () {
return $.get('/rating', {
annualFee: this.model.get('annualFee')
});
}
}),
annualFee: Model.attributeTypes.Number
}
}),
model = new FashionModel();
model.set('annualFee', 1000000);
model.ready().then(function () {
model.get('ratingIndex');
}).done();
fetch model.fetch()
Fetch data associated with model from storage.
var FashionModel = Model.inherit({
attributes: {
name: Model.attributeTypes.String
},
storage: Model.Storage.inherit({
find: function (model) {
return $.get('/models', {
id: model.getId()
});
}
})
}),
model = new FashionModel({id: id});
model.fetch().then(function () {
model.get('name');
}).done();
save model.save()
var FashionModel = Model.inherit({
attributes: {
id: Model.attributeTypes.Id,
name: Model.attributeTypes.String,
weight: Model.attributeTypes.Number
},
storage: Model.Storage.inherit({
insert: function (model) {
return $.post('/models', model.toJSON()).then(function (result) {
return result.id;
});
},
update: function (model) {
return $.put('/models', model.toJSON());
}
})
}),
model = new FashionModel();
model.set({
name: 'Kate',
weight: 55
});
model.save().then(function () { //create
model.getId(); //storage id
model.set('weight', 56);
return model.save(); //update
}).done()
remove model.remove()
Removes model from storage.
Model additional methods and properties
model.isNew()
model.isReady()
model.trigger(event)
model.calculate()
model.CHANGE_BRANCH
model.CALCULATIONS_BRANCH
These methods provided for advanced model extending. Consult source for details.
Model static methods and properties
Storage Model.Storage
Abstract class for model storage
var FashionModel = Model.inherit({
attributes: {
//..
},
storage: Model.Storage.inherit({
//..
})
});
Class storage Model.storage
Storage class
var SuperModel = FashionModel.inherit({
storage: FashionModel.storage.inherit({ //extend storage from FashionModel
//..
})
});
Attribute Model.Attribute
Base class for model attribute
var CustomAttribute = Model.attribute.inherit({
//..
})
Class attributes Model.attributes
Model class attributes
var SuperModel = FashionModel.inherit({
attributes: {
name: FashionModel.attributes.name,
weight: FashionModel.attributes.weight.inherit({
default: 50
})
}
});
Model.on([attributes], events, cb, [ctx])
Bind event on all models of class
FashionModel.on('change', this.changeHandler, this);
Model.un([attributes], events, cb, [ctx])
Unbind event on all models of class
List
Array like object returned for fields types List
and ModelsList
var Podium = Model.inherit({
attributes: {
models: Model.attributeTypes.ModelsList(FashionModel)
}
}),
podium = new Podium(data),
list = podium.get('models'), //instanceof List
model = list.get(0); //instanceof Model
Mutating methods
List inerits Array mutating methods: pop
, push
, reverse
, shift
, sort
, splice
, unshift
podium.get('models').push(new FashionModel());
list.get(index)
Get list item by index
podium.get('models').get(0);// instanceof Model
list.length()
Returns length of list
list.toArray()
Returns shallow copy of Array, wich stores List items
podium.get('models').forEach(function (model) {
model; // instanceof Model
});
ValidationError Model.ValidationError
Error class for validation fail report
Collection
inherit Collection.inherit(properties, [classPorperties])
Creates you own collection class by extending Collection. You should define modelType
property - constructor which will be used for new models.
var MyCollection = Collection.inherit({
modelType: MyModel
});
length collection.length
Number of models in collection.
at collection.at(index)
Returns model by index.
get collection.get(id)
Returns model by id.
where collection.where(conditions)
Returns models that match the conditions.
var collection = new MyCollection([{
name: 'John',
age: 40
}, {
name: 'Bob',
age: 40
},{
name: 'Jane'
age: 42
}]);
collection.where({age: 40}) // -> [Model.<{name: 'John', age: 40}>, Model.<{name: 'Bob', age: 40}>]
findWhere collection.findWhere(conditions)
Same as where
but returns first match.
pluck collection.pluck(attr)
Picks one attribute from each model in collection and return array of these attributes.
var collection = new MyCollection([{
name: 'John',
age: 40
}, {
name: 'Bob',
age: 40
},{
name: 'Jane'
age: 42
}]);
collection.pluck('name') // -> ['John', 'Bob', 'Jane']
add collection.add(models, [options])
Adds new model(s) to collection. models
can be an object or instance of Model
or array of objects or models. Triggers add
event.
options
options.at
- position where model(s) should be inserted. By default model adds to end of colleciton
remove collection.remove(models)
Removes models from collection. models
can be an instance of Model
or array of models. Triggers remove
event.
Note: When model removes via model.remove()
it will be removed from collection
set collection.set(models)
Removes all models in collection and adds new models
Other methods
Collection implements some array methods: forEach
, some
, every
, filter
, map
, reduce
, find
.
Also collection proxies methods to models: isChanged
, commit
, revert
, toJSON
.
Model events
All model events such as change
, change:attribute
, calculate
, commit
, commit:attribute
also wil be triggered on collection
run tests
$ npm test