ember install ember-changeset
We have released v3.0.0
. See the CHANGELOG here. This requires Ember >= 3.13 as the use of @tracked
will help us monitor and propagate changes to the UI layer. If your app is < 3.13 or you need to support IE11, then you can install the 2.0 series ember install [email protected]
.
Support for IE11 was dropped with the v3.0.0
release given our ubiquitous use of Proxy.
The base library for this addon is validated-changeset. As a result, this functionality is available outside of Ember as well!
The idea behind a changeset is simple: it represents a set of valid changes to be applied onto any Object (Ember.Object
, DS.Model
, POJOs, etc). Each change is tested against an optional validation, and if valid, the change is stored and applied when executed.
Given Ember's Data Down, Actions Up (DDAU) approach, a changeset is more appropriate compared to implicit 2 way bindings. Other validation libraries only validate a property after it is set on an Object, which means that your Object can enter an invalid state.
ember-changeset
only allows valid changes to be set, so your Objects will never become invalid (assuming you have 100% validation coverage). Additionally, this addon is designed to be un-opinionated about your choice of form and/or validation library, so you can easily integrate it into an existing solution.
The simplest way to incorporate validations is to use ember-changeset-validations
, a companion addon to this one. It has a simple mental model, and there are no Observers or CPs involved – just pure functions.
See also the plugins section for addons that extend ember-changeset
.
import { Changeset } from 'ember-changeset';
let changeset = Changeset(user, validatorFn);
user.get('firstName'); // "Michael"
user.get('lastName'); // "Bolton"
changeset.set('firstName', 'Jim');
changeset.set('lastName', 'B');
changeset.get('isInvalid'); // true
changeset.get('errors'); // [{ key: 'lastName', validation: 'too short', value: 'B' }]
changeset.set('lastName', 'Bob');
changeset.get('isValid'); // true
user.get('firstName'); // "Michael"
user.get('lastName'); // "Bolton"
changeset.save(); // sets and saves valid changes on the user
user.get('firstName'); // "Jim"
user.get('lastName'); // "Bob"
First, create a new Changeset
using the changeset
helper or through JavaScript via a factory function:
import Component from '@ember/component';
import { Changeset } from 'ember-changeset';
export default FormComponent extends Component {
init(...args) {
super.init(...args)
let validator = this.validate;
this.changeset = Changeset(this.model, validator);
}
}
The helper receives any Object (including DS.Model
, Ember.Object
, or even POJOs) and an optional validator
action. If a validator
is passed into the helper, the changeset will attempt to call that function when a value changes.
// application/controller.js
import Controller from '@ember/controller';
import { action } from '@ember/object';
export default class FormController extends Controller {
@action
submit(changeset) {
return changeset.save();
}
@action
rollback(changeset) {
return changeset.rollback();
}
@action
validate({ key, newValue, oldValue, changes, content }) {
// lookup a validator function on your favorite validation library
// and return a Boolean
}
}
Then, in your favorite form library, simply pass in the changeset
in place of the original model.
In the above example, when the input changes, only the changeset's internal values are updated. When the submit button is clicked, the changes are only executed if all changes are valid.
On rollback, all changes are dropped and the underlying Object is left untouched.
import { BufferedChangeset, Changeset } from 'ember-changeset';
const MyChangeset extends BufferedChangeset {
save() {
super.save(...arguments);
// my other stuff
}
}
let changeset = Changeset(user, validatorFn, { changeset: MyChangeset });
ember-changeset
overrides set
and get
in order to handle deeply nested setters. mut
is simply an alias for Ember.set(changeset, ...)
, thus we provide a changeset-set
template helper if you are dealing with nested setters.
changeset-get
is necessary for nested getters to easily retrieve leaf keys without error. Ember's templating layer will ask us for the first key it comes across as it traverses down the object (user.firstName
). We keep track of the changes, but to also keep track of unchanged values and properly merge them in the changeset is difficult. If you are only accessing keys in an object that is only one level deep, you do not need this helper.
In order to limit the changes made to your changeset and it's associated isDirty
state, you can pass in a list of changesetKeys
.
let changeset = Changeset(model, validatorFn, validationMap, { changesetKeys: ['name'] });
The default behavior of Changeset
is to automatically validate a field when it is set. Automatic validation can be disabled by passing skipValidate
as an option when creating a changeset.
let changeset = Changeset(model, validatorFn, validationMap, { skipValidate: true });
Be sure to call validate()
on the changeset
before saving or committing changes.
import Component from '@glimmer/component';
import { BufferedChangeset } from 'ember-changeset/types';
import { Changeset } from 'ember-changeset';
interface Args {
user: {
name: string;
age: number;
}
}
export default class Foo extends Component<Args> {
changeset: BufferedChangeset;
constructor(owner, args) {
super(owner, args);
this.changeset = Changeset(args.user);
}
}
Other available types include the following. Please put in a PR if you need more types or access directly in validated-changeset
!
import {
ValidationResult,
ValidatorMapFunc,
ValidatorAction
} from 'ember-changeset/types';
- Properties
- Methods
- Events
Returns the error object.
{
firstName: {
value: 'Jim',
validation: 'First name must be greater than 7 characters'
}
}
Note that keys can be arbitrarily nested:
{
address: {
zipCode: {
value: '123',
validation: 'Zip code must have 5 digits'
}
}
}
You can use this property to locate a single error:
Returns the change object.
{
firstName: 'Jim'
}
Note that keys can be arbitrarily nested:
{
address: {
zipCode: '10001'
}
}
You can use this property to locate a single change:
Returns an array of errors. If your validate
function returns a non-boolean value, it is added here as the validation
property.
[
{
key: 'firstName',
value: 'Jim',
validation: 'First name must be greater than 7 characters'
},
{
key: 'address.zipCode',
value: '123',
validation: 'Zip code must have 5 digits'
}
]
You can use this property to render a list of errors:
Returns an array of changes to be executed. Only valid changes will be stored on this property.
[
{
key: 'firstName',
value: 'Jim'
},
{
key: 'address.zipCode',
value: 10001
}
]
You can use this property to render a list of changes:
Returns the Object that was wrapped in the changeset.
let user = { name: 'Bobby', age: 21, address: { zipCode: '10001' } };
let changeset = Changeset(user);
changeset.get('data'); // user
Returns a Boolean value of the changeset's validity.
changeset.get('isValid'); // true
You can use this property in the template:
Returns a Boolean value of the changeset's (in)validity.
changeset.get('isInvalid'); // true
You can use this property in the template:
Returns a Boolean value of the changeset's state. A pristine changeset is one with no changes.
changeset.get('isPristine'); // true
If changes present on the changeset are equal to the content's, this will return true
. However, note that key/value pairs in the list of changes must all be present and equal on the content, but not necessarily vice versa:
let user = { name: 'Bobby', age: 21, address: { zipCode: '10001' } };
changeset.set('name', 'Bobby');
changeset.get('isPristine'); // true
changeset.set('address.zipCode', '10001');
changeset.get('isPristine'); // true
changeset.set('foo', 'bar');
changeset.get('isPristine'); // false
Returns a Boolean value of the changeset's state. A dirty changeset is one with changes.
changeset.get('isDirty'); // true
Exactly the same semantics as Ember.get
. This proxies first to the error value, the changed value, and finally to the underlying Object.
changeset.get('firstName'); // "Jim"
changeset.set('firstName', 'Billy'); // "Billy"
changeset.get('firstName'); // "Billy"
changeset.get('address.zipCode'); // "10001"
changeset.set('address.zipCode', '94016'); // "94016"
changeset.get('address.zipCode'); // "94016"
You can use and bind this property in the template:
Note that using Ember.get
will not necessarily work if you're expecting an Object. On the other hand, using changeset.get
will work just fine:
get(changeset, 'momentObj').format('dddd'); // will error, format is undefined
changeset.get('momentObj').format('dddd'); // => "Friday"
This is because Changeset
wraps an Object with Ember.ObjectProxy
internally, and overrides Ember.Object.get
to hide this implementation detail.
Because an Object is wrapped with Ember.ObjectProxy
, the following (although more verbose) will also work:
get(changeset, 'momentObj.content').format('dddd'); // => "Friday"
Exactly the same semantics as Ember.set
. This stores the change on the changeset. It is recommended to use changeset.set(...)
instead of Ember.set(changeset, ...)
. Ember.set
will set the property for nested keys on the underlying model.
changeset.set('firstName', 'Milton'); // "Milton"
changeset.set('address.zipCode', '10001'); // "10001"
You can use and bind this property in the template:
Any updates on this value will only store the change on the changeset, even with 2 way binding.
Provides a function to run before emitting changes to the model. The callback function must return a hash in the same shape:
changeset.prepare((changes) => {
// changes = { firstName: "Jim", lastName: "Bob", 'address.zipCode': "07030" };
let modified = {};
for (let key in changes) {
let newKey = key.split('.').map(underscore).join('.')
modified[newKey] = changes[key];
}
// don't forget to return, the original changes object is not mutated
// modified = { first_name: "Jim", last_name: "Bob", 'address.zip_code': "07030" };
return modified;
}); // returns changeset
The callback function is not validated – if you modify a value, it is your responsibility to ensure that it is valid.
Returns the changeset.
Applies the valid changes to the underlying Object.
changeset.execute(); // returns changeset
Note that executing the changeset will not remove the internal list of changes - instead, you should do so explicitly with rollback
or save
if that is desired.
Executes changes, then proxies to the underlying Object's save
method, if one exists. If it does, the method can either return a Promise
or a non-Promise
value. Either way, the changeset's save
method will return
a promise.
changeset.save(); // returns Promise
The save
method will also remove the internal list of changes if the save
is successful.
Merges 2 changesets and returns a new changeset with the same underlying content and validator as the origin. Both changesets must point to the same underlying object. For example:
let changesetA = Changeset(user, validatorFn);
let changesetB = Changeset(user, validatorFn);
changesetA.set('firstName', 'Jim');
changesetA.set('address.zipCode', '94016');
changesetB.set('firstName', 'Jimmy');
changesetB.set('lastName', 'Fallon');
changesetB.set('address.zipCode', '10112');
let changesetC = changesetA.merge(changesetB);
changesetC.execute();
user.get('firstName'); // "Jimmy"
user.get('lastName'); // "Fallon"
user.get('address.zipCode'); // "10112"
Note that both changesets A
and B
are not destroyed by the merge, so you might want to call destroy()
on them to avoid memory leaks.
Rolls back all unsaved changes and resets all errors.
changeset.rollback(); // returns changeset
Rolls back all invalid unsaved changes and resets all errors. Valid changes will be kept on the changeset.
changeset.rollbackInvalid(); // returns changeset
Rolls back unsaved changes for the specified property only. All other changes will be kept on the changeset.
// user = { firstName: "Jim", lastName: "Bob" };
let changeset = Changeset(user);
changeset.set('firstName', 'Jimmy');
changeset.set('lastName', 'Fallon');
changeset.rollbackProperty('lastName'); // returns changeset
changeset.execute();
user.get('firstName'); // "Jimmy"
user.get('lastName'); // "Bob"
Validates all, single or multiple fields on the changeset. This will also validate the property on the underlying object, and is a useful method if you require the changeset to validate immediately on render.
Note: This method requires a validation map to be passed in when the changeset is first instantiated.
user.set('lastName', 'B');
user.set('address.zipCode', '123');
let validationMap = {
lastName: validateLength({ min: 8 }),
// specify nested keys with pojo's
address: {
zipCode: : validateLength({ is: 5 })
}
};
let changeset = Changeset(user, validatorFn, validationMap);
changeset.get('isValid'); // true
// validate single field; returns Promise
changeset.validate('lastName');
changeset.validate('address.zipCode');
// multiple keys
changeset.validate('lastName', 'address.zipCode');
// validate all fields; returns Promise
changeset.validate().then(() => {
changeset.get('isInvalid'); // true
// [{ key: 'lastName', validation: 'too short', value: 'B' },
// { key: 'address.zipCode', validation: 'too short', value: '123' }]
changeset.get('errors');
});
Manually add an error to the changeset.
changeset.addError('email', {
value: '[email protected]',
validation: 'Email already taken'
});
changeset.addError('address.zip', {
value: '123',
validation: 'Must be 5 digits'
});
// shortcut
changeset.addError('email', 'Email already taken');
changeset.addError('address.zip', 'Must be 5 digits');
Adding an error manually does not require any special setup. The error will be cleared if the value for the key
is subsequently set to a valid value. Adding an error will overwrite any existing error or change for key
.
If using the shortcut method, the value in the changeset will be used as the value for the error.
Manually push errors to the changeset.
changeset.pushErrors('age', 'Too short', 'Not a valid number', 'Must be greater than 18');
changeset.pushErrors('dogYears.age', 'Too short', 'Not a valid number', 'Must be greater than 2.5');
This is compatible with ember-changeset-validations
, and allows you to either add a new error with multiple validation messages or push to an existing array of validation messages.
Creates a snapshot of the changeset's errors and changes. This can be used to restore
the changeset at a later time.
let snapshot = changeset.snapshot(); // snapshot
Restores a snapshot of changes and errors to the changeset. This overrides existing changes and errors.
let user = { name: 'Adam', address: { country: 'United States' } };
let changeset = Changeset(user, validatorFn);
changeset.set('name', 'Jim Bob');
changeset.set('address.country', 'North Korea');
let snapshot = changeset.snapshot();
changeset.set('name', 'Poteto');
changeset.set('address.country', 'Australia')
changeset.restore(snapshot);
changeset.get('name'); // "Jim Bob"
changeset.get('address.country'); // "North Korea"
Unlike Ecto.Changeset.cast
, cast
will take an array of allowed keys and remove unwanted keys off of the changeset.
let allowed = ['name', 'password', 'address.country'];
let changeset = Changeset(user, validatorFn);
changeset.set('name', 'Jim Bob');
changeset.set('address.country', 'United States');
changeset.set('unwantedProp', 'foo');
changeset.set('address.unwantedProp', 123);
changeset.get('unwantedProp'); // "foo"
changeset.get('address.unwantedProp'); // 123
changeset.cast(allowed); // returns changeset
changeset.get('unwantedProp'); // undefined
changeset.get('address.country'); // "United States"
changeset.get('another.unwantedProp'); // undefined
For example, this method can be used to only allow specified changes through prior to saving. This is especially useful if you also setup a schema
object for your model (using Ember Data), which can then be exported and used as a list of allowed keys:
// models/user.js
export const schema = {
name: attr('string'),
password: attr('string')
};
export default Model.extend(schema);
// controllers/foo.js
import { schema } from '../models/user';
const { keys } = Object;
export default Controller.extend({
// ...
actions: {
save(changeset) {
return changeset
.cast(keys(schema))
.save();
}
}
});
Checks to see if async validator for a given key has not resolved. If no key is provided it will check to see if any async validator is running.
changeset.set('lastName', 'Appleseed');
changeset.set('firstName', 'Johnny');
changeset.set('address.city', 'Anchorage');
changeset.validate();
changeset.isValidating(); // true if any async validation is still running
changeset.isValidating('lastName'); // true if lastName validation is async and still running
changeset.isValidating('address.city'); // true if address.city validation is async and still running
changeset.validate().then(() => {
changeset.isValidating(); // false since validations are complete
});
This event is triggered after isValidating is set to true for a key, but before the validation is complete.
changeset.on('beforeValidation', key => {
console.log(`${key} is validating...`);
});
changeset.validate();
changeset.isValidating(); // true
// console output: lastName is validating...
// console output: address.city is validating...
This event is triggered after async validations are complete and isValidating is set to false for a key.
changeset.on('afterValidation', key => {
console.log(`${key} has completed validating`);
});
changeset.validate().then(() => {
changeset.isValidating(); // false
// console output: lastName has completed validating
// console output: address.city has completed validating
});
This event is triggered after a rollback of the changeset. This can be used for some advanced use cases where it is necessary to separately track all changes that are made to the changeset.
changeset.on('afterRollback', () => {
console.log("changeset has rolled back");
});
changeset.rollback();
// console output: changeset has rolled back
To use with your favorite validation library, you should create a custom validator
action to be passed into the changeset:
// application/controller.js
import Controller from '@ember/controller';
import { action } from '@ember/object';
export default class FormController extends Controller {
@action
validate({ key, newValue, oldValue, changes, content }) {
// lookup a validator function on your favorite validation library
// should return a Boolean
}
}
Your action will receive a single POJO containing the key
, newValue
, oldValue
, a one way reference to changes
, and the original object content
.
When you run changeset.save()
, under the hood this executes the changeset, and then runs the save method on your original content object, passing its return value back to you. You are then free to use this result to add additional errors to the changeset via the addError
method, if applicable.
For example, if you are using an Ember Data model in your route, saving the changeset will save the model. If the save rejects, Ember Data will add errors to the model for you. To copy the model errors over to your changeset, add a handler like this:
changeset.save()
.then(() => { /* ... */ })
.catch(() => {
get(this, 'model.errors').forEach(({ attribute, message }) => {
changeset.pushErrors(attribute, message);
});
});
If you're uncertain whether or not you're dealing with a Changeset
, you can use the isChangeset
util.
import { isChangeset } from 'validated-changeset';
if (isChangeset(model)) {
model.execute();
// other changeset-specific code...
}
ember-changeset-validations
- Pure, functional validations without CPs or Observersember-changeset-cp-validations
- Work withember-cp-validations
ember-changeset-hofs
- Higher-order validation functionsember-bootstrap-changeset-validations
- Adds support for changeset validations toember-bootstrap
- General Input Helper with ember-concurrency
export default Component.extend({
classNameBindings: ['hasError:validated-input--error'],
_checkValidity: task(function* (changeset, valuePath, value) {
yield timeout(150);
let snapshot = changeset.snapshot();
// valuePath is the property on the changeset, e.g. firstName
changeset.set(valuePath, value);
if (!changeset.get(`error.${valuePath}`)) {
set(this, 'hasError', false);
} else {
// if error, restore changeset so don't show error in template immediately'
// i.e. wait for onblur action to validate and show error in template
changeset.restore(snapshot);
}
}).restartable(),
actions: {
/**
* @method validateProperty
* @param {Object} changeset
* @param {String} valuePath
* @param {Object} e
*/
validateProperty(changeset, valuePath, e) {
changeset.set(valuePath, e.target.value);
if (changeset.get(`error.${valuePath}`)) {
set(this, 'hasError', true);
} else {
set(this, 'hasError', false);
}
},
/**
* @method checkValidity
* @param {Object} changeset
* @param {String|Integer} value
*/
checkValidity(changeset, value) {
get(this, '_checkValidity').perform(changeset, this.valuePath, value);
}
}
});
We're grateful to these wonderful contributors who've contributed to ember-changeset
:
git clone
this repositorynpm install
ember serve
- Visit your app at http://localhost:4200.
npm test
(Runsember try:testall
to test your addon against multiple Ember versions)ember test
ember test --serve
ember build
For more information on using ember-cli, visit http://ember-cli.com/.