Class DS
Defined in: | addon/-private/core.js:8 |
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Module: | ember-data |
attr (type, options) Attribute
Module: | ember-data |
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Defined in addon/attr.js:38
- type
- String|Object
- the attribute type
- options
- Object
- a hash of options
- returns
- Attribute
DS.attr
defines an attribute on a DS.Model. By default, attributes are passed through as-is, however you can specify an optional type to have the value automatically transformed. Ember Data ships with four basic transform types: string
, number
, boolean
and date
. You can define your own transforms by subclassing DS.Transform.
Note that you cannot use attr
to define an attribute of id
.
DS.attr
takes an optional hash as a second parameter, currently supported options are:
-
defaultValue
: Pass a string or a function to be called to set the attributeto a default value if none is supplied.
Example
app/models/user.js
import DS from 'ember-data'; export default DS.Model.extend({ username: DS.attr('string'), email: DS.attr('string'), verified: DS.attr('boolean', { defaultValue: false }) });
Default value can also be a function. This is useful it you want to return a new object for each attribute.
app/models/user.js
import DS from 'ember-data'; export default DS.Model.extend({ username: DS.attr('string'), email: DS.attr('string'), settings: DS.attr({ defaultValue() { return {}; } }) });
The options
hash is passed as second argument to a transforms' serialize
and deserialize
method. This allows to configure a transformation and adapt the corresponding value, based on the config:
app/models/post.js
import DS from 'ember-data'; export default DS.Model.extend({ text: DS.attr('text', { uppercase: true }) });
app/transforms/text.js
import DS from 'ember-data'; export default DS.Transform.extend({ serialize(value, options) { if (options.uppercase) { return value.toUpperCase(); } return value; }, deserialize(value) { return value; } })
belongsTo (modelName, options) Ember.computed
Module: | ember-data |
---|
Defined in addon/-private/system/relationships/belongs-to.js:5
- modelName
- String
- (optional) type of the relationship
- options
- Object
- (optional) a hash of options
- returns
- Ember.computed
- relationship
DS.belongsTo
is used to define One-To-One and One-To-Many relationships on a DS.Model.
DS.belongsTo
takes an optional hash as a second parameter, currently supported options are:
-
async
: A boolean value used to explicitly declare this to be an async relationship. -
inverse
: A string used to identify the inverse property on a related model in a One-To-Many relationship. See Explicit Inverses
One-To-One
To declare a one-to-one relationship between two models, use DS.belongsTo
:
app/models/user.js
import DS from 'ember-data'; export default DS.Model.extend({ profile: DS.belongsTo('profile') });
app/models/profile.js
import DS from 'ember-data'; export default DS.Model.extend({ user: DS.belongsTo('user') });
One-To-Many
To declare a one-to-many relationship between two models, use DS.belongsTo
in combination with DS.hasMany
, like this:
app/models/post.js
import DS from 'ember-data'; export default DS.Model.extend({ comments: DS.hasMany('comment') });
app/models/comment.js
import DS from 'ember-data'; export default DS.Model.extend({ post: DS.belongsTo('post') });
You can avoid passing a string as the first parameter. In that case Ember Data will infer the type from the key name.
app/models/comment.js
import DS from 'ember-data'; export default DS.Model.extend({ post: DS.belongsTo() });
will lookup for a Post type.
errorsArrayToHash (errors) Object public
Module: | ember-data |
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Defined in addon/-private/adapters/errors.js:398
- errors
- Array
- array of errors in JSON-API format
- returns
- Object
Convert an array of errors in JSON-API format into an object.
import DS from 'ember-data'; const { errorsArrayToHash } = DS; let errorsArray = [ { title: 'Invalid Attribute', detail: 'Must be present', source: { pointer: '/data/attributes/name' } }, { title: 'Invalid Attribute', detail: 'Must be present', source: { pointer: '/data/attributes/age' } }, { title: 'Invalid Attribute', detail: 'Must be a number', source: { pointer: '/data/attributes/age' } } ]; let errors = errorsArrayToHash(errorsArray); // { // "name": ["Must be present"], // "age": ["Must be present", "must be a number"] // }
errorsHashToArray (errors) Array public
Module: | ember-data |
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Defined in addon/-private/adapters/errors.js:325
- errors
- Object
- hash with errors as properties
- returns
- Array
- array of errors in JSON-API format
Convert an hash of errors into an array with errors in JSON-API format.
import DS from 'ember-data'; const { errorsHashToArray } = DS; let errors = { base: 'Invalid attributes on saving this record', name: 'Must be present', age: ['Must be present', 'Must be a number'] }; let errorsArray = errorsHashToArray(errors); // [ // { // title: "Invalid Document", // detail: "Invalid attributes on saving this record", // source: { pointer: "/data" } // }, // { // title: "Invalid Attribute", // detail: "Must be present", // source: { pointer: "/data/attributes/name" } // }, // { // title: "Invalid Attribute", // detail: "Must be present", // source: { pointer: "/data/attributes/age" } // }, // { // title: "Invalid Attribute", // detail: "Must be a number", // source: { pointer: "/data/attributes/age" } // } // ]
hasMany (type, options) Ember.computed
Module: | ember-data |
---|
Defined in addon/-private/system/relationships/has-many.js:12
- type
- String
- (optional) type of the relationship
- options
- Object
- (optional) a hash of options
- returns
- Ember.computed
- relationship
DS.hasMany
is used to define One-To-Many and Many-To-Many relationships on a DS.Model.
DS.hasMany
takes an optional hash as a second parameter, currently supported options are:
-
async
: A boolean value used to explicitly declare this to be an async relationship. -
inverse
: A string used to identify the inverse property on a related model.
One-To-Many
To declare a one-to-many relationship between two models, use DS.belongsTo
in combination with DS.hasMany
, like this:
app/models/post.js
import DS from 'ember-data'; export default DS.Model.extend({ comments: DS.hasMany('comment') });
app/models/comment.js
import DS from 'ember-data'; export default DS.Model.extend({ post: DS.belongsTo('post') });
Many-To-Many
To declare a many-to-many relationship between two models, use DS.hasMany
:
app/models/post.js
import DS from 'ember-data'; export default DS.Model.extend({ tags: DS.hasMany('tag') });
app/models/tag.js
import DS from 'ember-data'; export default DS.Model.extend({ posts: DS.hasMany('post') });
You can avoid passing a string as the first parameter. In that case Ember Data will infer the type from the singularized key name.
app/models/post.js
import DS from 'ember-data'; export default DS.Model.extend({ tags: DS.hasMany() });
will lookup for a Tag type.
Explicit Inverses
Ember Data will do its best to discover which relationships map to one another. In the one-to-many code above, for example, Ember Data can figure out that changing the comments
relationship should update the post
relationship on the inverse because post is the only relationship to that model.
However, sometimes you may have multiple belongsTo
/hasMany
for the same type. You can specify which property on the related model is the inverse using DS.hasMany
's inverse
option:
app/models/comment.js
import DS from 'ember-data'; export default DS.Model.extend({ onePost: DS.belongsTo('post'), twoPost: DS.belongsTo('post'), redPost: DS.belongsTo('post'), bluePost: DS.belongsTo('post') });
app/models/post.js
import DS from 'ember-data'; export default DS.Model.extend({ comments: DS.hasMany('comment', { inverse: 'redPost' }) });
You can also specify an inverse on a belongsTo
, which works how you'd expect.
normalizeModelName (modelName) String public
Module: | ember-data |
---|
Defined in addon/-private/system/normalize-model-name.js:6
- modelName
- String
- returns
- String
- normalizedModelName
This method normalizes a modelName into the format Ember Data uses internally.
© 2020 Yehuda Katz, Tom Dale and Ember.js contributors
Licensed under the MIT License.
https://api.emberjs.com/ember-data/2.18/classes/DS/methods