Class DS.RESTAdapter

The REST adapter allows your store to communicate with an HTTP server by transmitting JSON via XHR. Most Ember.js apps that consume a JSON API should use the REST adapter.

This adapter is designed around the idea that the JSON exchanged with the server should be conventional.

Success and failure

The REST adapter will consider a success any response with a status code of the 2xx family ("Success"), as well as 304 ("Not Modified"). Any other status code will be considered a failure.

On success, the request promise will be resolved with the full response payload.

Failed responses with status code 422 ("Unprocessable Entity") will be considered "invalid". The response will be discarded, except for the errors key. The request promise will be rejected with a DS.InvalidError. This error object will encapsulate the saved errors value.

Any other status codes will be treated as an "adapter error". The request promise will be rejected, similarly to the "invalid" case, but with an instance of DS.AdapterError instead.

JSON Structure

The REST adapter expects the JSON returned from your server to follow these conventions.

Object Root

The JSON payload should be an object that contains the record inside a root property. For example, in response to a GET request for /posts/1, the JSON should look like this:

{
  "posts": {
    "id": 1,
    "title": "I'm Running to Reform the W3C's Tag",
    "author": "Yehuda Katz"
  }
}

Similarly, in response to a GET request for /posts, the JSON should look like this:

{
  "posts": [
    {
      "id": 1,
      "title": "I'm Running to Reform the W3C's Tag",
      "author": "Yehuda Katz"
    },
    {
      "id": 2,
      "title": "Rails is omakase",
      "author": "D2H"
    }
  ]
}

Note that the object root can be pluralized for both a single-object response and an array response: the REST adapter is not strict on this. Further, if the HTTP server responds to a GET request to /posts/1 (e.g. the response to a findRecord query) with more than one object in the array, Ember Data will only display the object with the matching ID.

Conventional Names

Attribute names in your JSON payload should be the camelCased versions of the attributes in your Ember.js models.

For example, if you have a Person model:

app/models/person.js
import DS from 'ember-data';

export default DS.Model.extend({
  firstName: DS.attr('string'),
  lastName: DS.attr('string'),
  occupation: DS.attr('string')
});

The JSON returned should look like this:

{
  "people": {
    "id": 5,
    "firstName": "Zaphod",
    "lastName": "Beeblebrox",
    "occupation": "President"
  }
}

Relationships

Relationships are usually represented by ids to the record in the relationship. The related records can then be sideloaded in the response under a key for the type.

{
  "posts": {
    "id": 5,
    "title": "I'm Running to Reform the W3C's Tag",
    "author": "Yehuda Katz",
    "comments": [1, 2]
  },
  "comments": [{
    "id": 1,
    "author": "User 1",
    "message": "First!",
  }, {
    "id": 2,
    "author": "User 2",
    "message": "Good Luck!",
  }]
}

If the records in the relationship are not known when the response is serialized its also possible to represent the relationship as a url using the links key in the response. Ember Data will fetch this url to resolve the relationship when it is accessed for the first time.

{
  "posts": {
    "id": 5,
    "title": "I'm Running to Reform the W3C's Tag",
    "author": "Yehuda Katz",
    "links": {
      "comments": "/posts/5/comments"
    }
  }
}

Errors

If a response is considered a failure, the JSON payload is expected to include a top-level key errors, detailing any specific issues. For example:

{
  "errors": {
    "msg": "Something went wrong"
  }
}

This adapter does not make any assumptions as to the format of the errors object. It will simply be passed along as is, wrapped in an instance of DS.InvalidError or DS.AdapterError. The serializer can interpret it afterwards.

Customization

Endpoint path customization

Endpoint paths can be prefixed with a namespace by setting the namespace property on the adapter:

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  namespace: 'api/1'
});

Requests for the Person model would now target /api/1/people/1.

Host customization

An adapter can target other hosts by setting the host property.

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  host: 'https://api.example.com'
});

Headers customization

Some APIs require HTTP headers, e.g. to provide an API key. Arbitrary headers can be set as key/value pairs on the RESTAdapter's headers object and Ember Data will send them along with each ajax request.

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  headers: {
    'API_KEY': 'secret key',
    'ANOTHER_HEADER': 'Some header value'
  }
});

headers can also be used as a computed property to support dynamic headers. In the example below, the session object has been injected into an adapter by Ember's container.

app/adapters/application.js
import DS from 'ember-data';
import { computed } from '@ember/object';

export default DS.RESTAdapter.extend({
  headers: computed('session.authToken', function() {
    return {
      'API_KEY': this.get('session.authToken'),
      'ANOTHER_HEADER': 'Some header value'
    };
  })
});

In some cases, your dynamic headers may require data from some object outside of Ember's observer system (for example document.cookie). You can use the volatile function to set the property into a non-cached mode causing the headers to be recomputed with every request.

app/adapters/application.js
import DS from 'ember-data';
import { get } from '@ember/object';
import { computed } from '@ember/object';

export default DS.RESTAdapter.extend({
  headers: computed(function() {
    return {
      'API_KEY': get(document.cookie.match(/apiKey\=([^;]*)/), '1'),
      'ANOTHER_HEADER': 'Some header value'
    };
  }).volatile()
});

Show:

Module: ember-data
modelName
String
id
(String|Array|Object)

single id or array of ids or query

snapshot
(DS.Snapshot|Array)

single snapshot or array of snapshots

requestType
String
query
Object

object of query parameters to send for query requests.

returns
String

url

Builds a URL for a given type and optional ID.

By default, it pluralizes the type's name (for example, 'post' becomes 'posts' and 'person' becomes 'people'). To override the pluralization see pathForType.

If an ID is specified, it adds the ID to the path generated for the type, separated by a /.

When called by RESTAdapter.findMany() the id and snapshot parameters will be arrays of ids and snapshots.

Module: ember-data
store
DS.Store
type
DS.Model
snapshot
DS.Snapshot
returns
Promise

promise

Called by the store when a newly created record is saved via the save method on a model record instance.

The createRecord method serializes the record and makes an Ajax (HTTP POST) request to a URL computed by buildURL.

See serialize for information on how to customize the serialized form of a record.

Module: ember-data
store
DS.Store
type
DS.Model
snapshot
DS.Snapshot
returns
Promise

promise

Called by the store when a record is deleted.

The deleteRecord method makes an Ajax (HTTP DELETE) request to a URL computed by buildURL.

Module: ember-data
store
DS.Store
type
DS.Model
sinceToken
String
snapshotRecordArray
DS.SnapshotRecordArray
returns
Promise

promise

Called by the store in order to fetch a JSON array for all of the records for a given type.

The findAll method makes an Ajax (HTTP GET) request to a URL computed by buildURL, and returns a promise for the resulting payload.

Module: ember-data
store
DS.Store
snapshot
DS.Snapshot
url
String
relationship
Object

meta object describing the relationship

returns
Promise

promise

Called by the store in order to fetch the JSON for the unloaded record in a belongs-to relationship that was originally specified as a URL (inside of links).

For example, if your original payload looks like this:

{
  "person": {
    "id": 1,
    "name": "Tom Dale",
    "links": { "group": "/people/1/group" }
  }
}

This method will be called with the parent record and /people/1/group.

The findBelongsTo method will make an Ajax (HTTP GET) request to the originally specified URL.

The format of your links value will influence the final request URL via the urlPrefix method:

  • Links beginning with //, http://, https://, will be used as is, with no further manipulation.

  • Links beginning with a single / will have the current adapter's host value prepended to it.

  • Links with no beginning / will have a parentURL prepended to it, via the current adapter's buildURL.

Module: ember-data
store
DS.Store
snapshot
DS.Snapshot
url
String
relationship
Object

meta object describing the relationship

returns
Promise

promise

Called by the store in order to fetch a JSON array for the unloaded records in a has-many relationship that were originally specified as a URL (inside of links).

For example, if your original payload looks like this:

{
  "post": {
    "id": 1,
    "title": "Rails is omakase",
    "links": { "comments": "/posts/1/comments" }
  }
}

This method will be called with the parent record and /posts/1/comments.

The findHasMany method will make an Ajax (HTTP GET) request to the originally specified URL.

The format of your links value will influence the final request URL via the urlPrefix method:

  • Links beginning with //, http://, https://, will be used as is, with no further manipulation.

  • Links beginning with a single / will have the current adapter's host value prepended to it.

  • Links with no beginning / will have a parentURL prepended to it, via the current adapter's buildURL.

Module: ember-data
store
DS.Store
type
DS.Model
ids
Array
snapshots
Array
returns
Promise

promise

Called by the store in order to fetch several records together if coalesceFindRequests is true

For example, if the original payload looks like:

{
  "id": 1,
  "title": "Rails is omakase",
  "comments": [ 1, 2, 3 ]
}

The IDs will be passed as a URL-encoded Array of IDs, in this form:

ids[]=1&ids[]=2&ids[]=3

Many servers, such as Rails and PHP, will automatically convert this URL-encoded array into an Array for you on the server-side. If you want to encode the IDs, differently, just override this (one-line) method.

The findMany method makes an Ajax (HTTP GET) request to a URL computed by buildURL, and returns a promise for the resulting payload.

Module: ember-data

Available since v1.13.0

store
DS.Store
type
DS.Model
id
String
snapshot
DS.Snapshot
returns
Promise

promise

Called by the store in order to fetch the JSON for a given type and ID.

The findRecord method makes an Ajax request to a URL computed by buildURL, and returns a promise for the resulting payload.

This method performs an HTTP GET request with the id provided as part of the query string.

Module: ember-data
store
DS.Store
type
DS.Model

the DS.Model class of the record

inputProperties
Object

a hash of properties to set on the newly created record.

returns
(String|Number)

id

If the globally unique IDs for your records should be generated on the client, implement the generateIdForRecord() method. This method will be invoked each time you create a new record, and the value returned from it will be assigned to the record's primaryKey.

Most traditional REST-like HTTP APIs will not use this method. Instead, the ID of the record will be set by the server, and your adapter will update the store with the new ID when it calls didCreateRecord(). Only implement this method if you intend to generate record IDs on the client-side.

The generateIdForRecord() method will be invoked with the requesting store as the first parameter and the newly created record as the second parameter:

import DS from 'ember-data';
import { v4 } from 'uuid';

export default DS.Adapter.extend({
  generateIdForRecord(store, inputProperties) {
    return v4();
  }
});
Module: ember-data
store
DS.Store
snapshots
Array
returns
Array

an array of arrays of records, each of which is to be loaded separately by findMany.

Organize records into groups, each of which is to be passed to separate calls to findMany.

This implementation groups together records that have the same base URL but differing ids. For example /comments/1 and /comments/2 will be grouped together because we know findMany can coalesce them together as /comments?ids[]=1&ids[]=2

It also supports urls where ids are passed as a query param, such as /comments?id=1 but not those where there is more than 1 query param such as /comments?id=2&name=David Currently only the query param of id is supported. If you need to support others, please override this or the _stripIDFromURL method.

It does not group records that have differing base urls, such as for example: /posts/1/comments/2 and /posts/2/comments/3

Module: ember-data

Available since v1.13.0

status
Number
headers
Object
payload
Object
requestData
Object
  • the original request information
returns
Object | DS.AdapterError

response

Takes an ajax response, and returns the json payload or an error.

By default this hook just returns the json payload passed to it. You might want to override it in two cases:

  1. Your API might return useful results in the response headers. Response headers are passed in as the second argument.

  2. Your API might return errors as successful responses with status code 200 and an Errors text or object. You can return a DS.InvalidError or a DS.AdapterError (or a sub class) from this hook and it will automatically reject the promise and put your record into the invalid or error state.

Returning a DS.InvalidError from this method will cause the record to transition into the invalid state and make the errors object available on the record. When returning an DS.InvalidError the store will attempt to normalize the error data returned from the server using the serializer's extractErrors method.

Module: ember-data

Available since v1.13.0

status
Number
headers
Object
payload
Object
returns
Boolean

Default handleResponse implementation uses this hook to decide if the response is an invalid error.

Module: ember-data

Available since v1.13.0

status
Number
headers
Object
payload
Object
returns
Boolean

Default handleResponse implementation uses this hook to decide if the response is a success.

Module: ember-data
modelName
String
returns
String

path

Determines the pathname for a given type.

By default, it pluralizes the type's name (for example, 'post' becomes 'posts' and 'person' becomes 'people').

Pathname customization

For example if you have an object LineItem with an endpoint of "/line_items/".

app/adapters/application.js
import DS from 'ember-data';
import { decamelize } from '@ember/string';
import { pluralize } from 'ember-inflector';

export default DS.RESTAdapter.extend({
  pathForType: function(modelName) {
    var decamelized = decamelize(modelName);
    return pluralize(decamelized);
  }
});
Module: ember-data
store
DS.Store
type
DS.Model
query
Object
returns
Promise

promise

Called by the store in order to fetch a JSON array for the records that match a particular query.

The query method makes an Ajax (HTTP GET) request to a URL computed by buildURL, and returns a promise for the resulting payload.

The query argument is a simple JavaScript object that will be passed directly to the server as parameters.

Module: ember-data

Available since v1.13.0

store
DS.Store
type
DS.Model
query
Object
returns
Promise

promise

Called by the store in order to fetch a JSON object for the record that matches a particular query.

The queryRecord method makes an Ajax (HTTP GET) request to a URL computed by buildURL, and returns a promise for the resulting payload.

The query argument is a simple JavaScript object that will be passed directly to the server as parameters.

Module: ember-data
snapshot
DS.Snapshot
options
Object
returns
Object

serialized snapshot

Proxies to the serializer's serialize method.

Example

app/adapters/application.js
import DS from 'ember-data';

export default DS.Adapter.extend({
  createRecord(store, type, snapshot) {
    let data = this.serialize(snapshot, { includeId: true });
    let url = `/${type.modelName}`;

    // ...
  }
});
Module: ember-data

Available since v1.13.0

store
DS.Store
snapshotRecordArray
DS.SnapshotRecordArray
returns
Boolean

This method is used by the store to determine if the store should reload a record array after the store.findAll method resolves with a cached record array.

This method is only checked by the store when the store is returning a cached record array.

If this method returns true the store will re-fetch all records from the adapter.

For example, if you do not want to fetch complex data over a mobile connection, or if the network is down, you can implement shouldBackgroundReloadAll as follows:

shouldBackgroundReloadAll(store, snapshotArray) {
  let connection = window.navigator.connection;

  if (connection === 'cellular' || connection === 'none') {
    return false;
  } else {
    return true;
  }
}

By default this method returns true, indicating that a background reload should always be triggered.

Module: ember-data

Available since v1.13.0

store
DS.Store
snapshot
DS.Snapshot
returns
Boolean

This method is used by the store to determine if the store should reload a record after the store.findRecord method resolves a cached record.

This method is only checked by the store when the store is returning a cached record.

If this method returns true the store will re-fetch a record from the adapter.

For example, if you do not want to fetch complex data over a mobile connection, or if the network is down, you can implement shouldBackgroundReloadRecord as follows:

shouldBackgroundReloadRecord(store, snapshot) {
  let connection = window.navigator.connection;

  if (connection === 'cellular' || connection === 'none') {
    return false;
  } else {
    return true;
  }
}

By default this hook returns true so the data for the record is updated in the background.

Module: ember-data

Available since v1.13.0

store
DS.Store
snapshotRecordArray
DS.SnapshotRecordArray
returns
Boolean

This method is used by the store to determine if the store should reload all records from the adapter when records are requested by store.findAll.

If this method returns true, the store will re-fetch all records from the adapter. If this method returns false, the store will resolve immediately using the cached records.

For example, if you are building an events ticketing system, in which users can only reserve tickets for 20 minutes at a time, and want to ensure that in each route you have data that is no more than 20 minutes old you could write:

shouldReloadAll(store, snapshotArray) {
  let snapshots = snapshotArray.snapshots();

  return snapshots.any((ticketSnapshot) => {
    let lastAccessedAt = ticketSnapshot.attr('lastAccessedAt');
    let timeDiff = moment().diff(lastAccessedAt, 'minutes');

    if (timeDiff > 20) {
      return true;
    } else {
      return false;
    }
  });
}

This method would ensure that whenever you do store.findAll('ticket') you will always get a list of tickets that are no more than 20 minutes old. In case a cached version is more than 20 minutes old, findAll will not resolve until you fetched the latest versions.

By default this methods returns true if the passed snapshotRecordArray is empty (meaning that there are no records locally available yet), otherwise it returns false.

Note that, with default settings, shouldBackgroundReloadAll will always re-fetch all the records in the background even if shouldReloadAll returns false. You can override shouldBackgroundReloadAll if this does not suit your use case.

Module: ember-data

Available since v1.13.0

store
DS.Store
snapshot
DS.Snapshot
returns
Boolean

This method is used by the store to determine if the store should reload a record from the adapter when a record is requested by store.findRecord.

If this method returns true, the store will re-fetch a record from the adapter. If this method returns false, the store will resolve immediately using the cached record.

For example, if you are building an events ticketing system, in which users can only reserve tickets for 20 minutes at a time, and want to ensure that in each route you have data that is no more than 20 minutes old you could write:

shouldReloadRecord(store, ticketSnapshot) {
  let lastAccessedAt = ticketSnapshot.attr('lastAccessedAt');
  let timeDiff = moment().diff(lastAccessedAt, 'minutes');

  if (timeDiff > 20) {
    return true;
  } else {
    return false;
  }
}

This method would ensure that whenever you do store.findRecord('ticket', id) you will always get a ticket that is no more than 20 minutes old. In case the cached version is more than 20 minutes old, findRecord will not resolve until you fetched the latest version.

By default this hook returns false, as most UIs should not block user interactions while waiting on data update.

Note that, with default settings, shouldBackgroundReloadRecord will always re-fetch the records in the background even if shouldReloadRecord returns false. You can override shouldBackgroundReloadRecord if this does not suit your use case.

Module: ember-data
obj
Object
returns
Object

By default, the RESTAdapter will send the query params sorted alphabetically to the server.

For example:

store.query('posts', { sort: 'price', category: 'pets' });

will generate a requests like this /posts?category=pets&sort=price, even if the parameters were specified in a different order.

That way the generated URL will be deterministic and that simplifies caching mechanisms in the backend.

Setting sortQueryParams to a falsey value will respect the original order.

In case you want to sort the query parameters with a different criteria, set sortQueryParams to your custom sort function.

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  sortQueryParams(params) {
    let sortedKeys = Object.keys(params).sort().reverse();
    let len = sortedKeys.length, newParams = {};

    for (let i = 0; i < len; i++) {
      newParams[sortedKeys[i]] = params[sortedKeys[i]];
    }

    return newParams;
  }
});
Module: ember-data
store
DS.Store
type
DS.Model
snapshot
DS.Snapshot
returns
Promise

promise

Called by the store when an existing record is saved via the save method on a model record instance.

The updateRecord method serializes the record and makes an Ajax (HTTP PUT) request to a URL computed by buildURL.

See serialize for information on how to customize the serialized form of a record.

Module: ember-data
modelName
String
snapshot
DS.Snapshot
returns
String

url

Builds a URL for a record.save() call when the record was created locally using store.createRecord().

Example:

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  urlForCreateRecord(modelName, snapshot) {
    return this._super(...arguments) + '/new';
  }
});
Module: ember-data
id
String
modelName
String
snapshot
DS.Snapshot
returns
String

url

Builds a URL for a record.save() call when the record has been deleted locally.

Example:

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  urlForDeleteRecord(id, modelName, snapshot) {
    return this._super(...arguments) + '/destroy';
  }
});
Module: ember-data
modelName
String
snapshot
DS.SnapshotRecordArray
returns
String

url

Builds a URL for a store.findAll(type) call.

Example:

app/adapters/comment.js
import DS from 'ember-data';

export default DS.JSONAPIAdapter.extend({
  urlForFindAll(modelName, snapshot) {
    return 'data/comments.json';
  }
});
Module: ember-data
id
String
modelName
String
snapshot
DS.Snapshot
returns
String

url

Builds a URL for fetching a async belongsTo relationship when a url is not provided by the server.

Example:

app/adapters/application.js
import DS from 'ember-data';

export default DS.JSONAPIAdapter.extend({
  urlForFindBelongsTo(id, modelName, snapshot) {
    let baseUrl = this.buildURL(id, modelName);
    return `${baseUrl}/relationships`;
  }
});
Module: ember-data
id
String
modelName
String
snapshot
DS.Snapshot
returns
String

url

Builds a URL for fetching a async hasMany relationship when a url is not provided by the server.

Example:

app/adapters/application.js
import DS from 'ember-data';

export default DS.JSONAPIAdapter.extend({
  urlForFindHasMany(id, modelName, snapshot) {
    let baseUrl = this.buildURL(id, modelName);
    return `${baseUrl}/relationships`;
  }
});
Module: ember-data
ids
Array
modelName
String
snapshots
Array
returns
String

url

Builds a URL for coalesceing multiple store.findRecord(type, id) records into 1 request when the adapter's coalesceFindRequests property is true.

Example:

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  urlForFindMany(ids, modelName) {
    let baseUrl = this.buildURL();
    return `${baseUrl}/coalesce`;
  }
});
Module: ember-data
id
String
modelName
String
snapshot
DS.Snapshot
returns
String

url

Builds a URL for a store.findRecord(type, id) call.

Example:

app/adapters/user.js
import DS from 'ember-data';

export default DS.JSONAPIAdapter.extend({
  urlForFindRecord(id, modelName, snapshot) {
    let baseUrl = this.buildURL(modelName, id, snapshot);
    return `${baseUrl}/users/${snapshot.adapterOptions.user_id}/playlists/${id}`;
  }
});
Module: ember-data
query
Object
modelName
String
returns
String

url

Builds a URL for a store.query(type, query) call.

Example:

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  host: 'https://api.github.com',
  urlForQuery (query, modelName) {
    switch(modelName) {
      case 'repo':
        return `https://api.github.com/orgs/${query.orgId}/repos`;
      default:
        return this._super(...arguments);
    }
  }
});
Module: ember-data
query
Object
modelName
String
returns
String

url

Builds a URL for a store.queryRecord(type, query) call.

Example:

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  urlForQueryRecord({ slug }, modelName) {
    let baseUrl = this.buildURL();
    return `${baseUrl}/${encodeURIComponent(slug)}`;
  }
});
Module: ember-data
id
String
modelName
String
snapshot
DS.Snapshot
returns
String

url

Builds a URL for a record.save() call when the record has been update locally.

Example:

app/adapters/application.js
import DS from 'ember-data';

export default DS.RESTAdapter.extend({
  urlForUpdateRecord(id, modelName, snapshot) {
    return `/${id}/feed?access_token=${snapshot.adapterOptions.token}`;
  }
});