DS.RESTAdapter
DS.RESTAdapter Class
Extends: DS.Adapter
Uses: DS.BuildURLMixin
Defined in: addon/adapters/rest.js:31
Module: ember-data
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'; export default DS.RESTAdapter.extend({ headers: Ember.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'; export default DS.RESTAdapter.extend({ headers: Ember.computed(function() { return { 'API_KEY': Ember.get(document.cookie.match(/apiKey\=([^;]*)/), '1'), 'ANOTHER_HEADER': 'Some header value' }; }).volatile() });
_ajaxRequest (options) private
Parameters:
-
options
Object
- jQuery ajax options to be used for the ajax request
_makeRequest (request) Promise
private
Make a request using jQuery.ajax
.
Parameters:
-
request
Object
Returns:
-
Promise
- promise
_requestFor (params) Object
private
Get an object which contains all properties for a request which should be made.
Parameters:
-
params
Object
Returns:
-
Object
- request object
_requestToJQueryAjaxHash (request) Object
private
Convert a request object into a hash which can be passed to jQuery.ajax
.
Parameters:
-
request
Object
Returns:
-
Object
- jQuery ajax hash
ajax (url, type, options) Promise
private
Takes a URL, an HTTP method and a hash of data, and makes an HTTP request.
When the server responds with a payload, Ember Data will call into extractSingle
or extractArray
(depending on whether the original query was for one record or many records).
By default, ajax
method has the following behavior:
- It sets the response
dataType
to"json"
- If the HTTP method is not
"GET"
, it sets theContent-Type
to beapplication/json; charset=utf-8
- If the HTTP method is not
"GET"
, it stringifies the data passed in. The data is the serialized record in the case of a save. - Registers success and failure handlers.
Parameters:
-
url
String
-
type
String
- The request type GET, POST, PUT, DELETE etc.
-
options
Object
Returns:
-
Promise
- promise
ajaxOptions (url, type, options) Object
private
Parameters:
-
url
String
-
type
String
- The request type GET, POST, PUT, DELETE etc.
-
options
Object
Returns:
-
Object
createRecord (store, type, snapshot) 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.
Parameters:
-
store
DS.Store
-
type
DS.Model
-
snapshot
DS.Snapshot
Returns:
-
Promise
- promise
dataForRequest (params) Object
public
Get the data (body or query params) for a request.
Parameters:
-
params
Object
Returns:
-
Object
- data
deleteRecord (store, type, snapshot) 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
.
Parameters:
-
store
DS.Store
-
type
DS.Model
-
snapshot
DS.Snapshot
Returns:
-
Promise
- promise
findAll (store, type, sinceToken, snapshotRecordArray) 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.
Parameters:
-
store
DS.Store
-
type
DS.Model
-
sinceToken
String
-
snapshotRecordArray
DS.SnapshotRecordArray
Returns:
-
Promise
- promise
findBelongsTo (store, snapshot, url) 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'shost
value prepended to it.Links with no beginning
/
will have a parentURL prepended to it, via the current adapter'sbuildURL
.
Parameters:
-
store
DS.Store
-
snapshot
DS.Snapshot
-
url
String
Returns:
-
Promise
- promise
findHasMany (store, snapshot, relationship, url) 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'shost
value prepended to it.Links with no beginning
/
will have a parentURL prepended to it, via the current adapter'sbuildURL
.
Parameters:
-
store
DS.Store
-
snapshot
DS.Snapshot
-
relationship
Object
- meta object describing the relationship
-
url
String
Returns:
-
Promise
- promise
findMany (store, type, ids, snapshots) 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.
Returns:
-
Promise
- promise
findRecord (store, type, id, snapshot) 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.
Parameters:
-
store
DS.Store
-
type
DS.Model
-
id
String
-
snapshot
DS.Snapshot
Returns:
-
Promise
- promise
generatedDetailedMessage (status, headers, payload, requestData) String
private
Generates a detailed ("friendly") error message, with plenty of information for debugging (good luck!)
Parameters:
-
status
Number
-
headers
Object
-
payload
Object
-
requestData
Object
Returns:
-
String
- detailed error message
groupRecordsForFindMany (store, snapshots) Array
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
Parameters:
-
store
DS.Store
-
snapshots
Array
Returns:
-
Array
- an array of arrays of records, each of which is to be loaded separately by `findMany`.
handleResponse (status, headers, payload, requestData) Object | DS.AdapterError
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:
Your API might return useful results in the response headers. Response headers are passed in as the second argument.
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 aDS.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.
Parameters:
-
status
Number
-
headers
Object
-
payload
Object
-
requestData
Object
- - the original request information
Returns:
-
Object | DS.AdapterError
- response
headersForRequest (params) Object
public
Get the headers for a request.
By default the value of the headers
property of the adapter is returned.
Parameters:
-
params
Object
Returns:
-
Object
- headers
isInvalid (status, headers, payload) Boolean
Default handleResponse
implementation uses this hook to decide if the response is an invalid error.
Parameters:
-
status
Number
-
headers
Object
-
payload
Object
Returns:
-
Boolean
isSuccess (status, headers, payload) Boolean
Default handleResponse
implementation uses this hook to decide if the response is a success.
Parameters:
-
status
Number
-
headers
Object
-
payload
Object
Returns:
-
Boolean
methodForRequest (params) String
public
Get the HTTP method for a request.
Parameters:
-
params
Object
Returns:
-
String
- HTTP method
normalizeErrorResponse (status, headers, payload) Array
private
Parameters:
-
status
Number
-
headers
Object
-
payload
Object
Returns:
-
Array
- errors payload
parseErrorResponse (responseText) Object
private
Parameters:
-
responseText
String
Returns:
-
Object
query (store, type, query) 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.
Returns:
-
Promise
- promise
queryRecord (store, type, query) 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.
Returns:
-
Promise
- promise
sortQueryParams (obj) 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; } });
Parameters:
-
obj
Object
Returns:
-
Object
updateRecord (store, type, snapshot) 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.
Parameters:
-
store
DS.Store
-
type
DS.Model
-
snapshot
DS.Snapshot
Returns:
-
Promise
- promise
urlForRequest (params) String
public
Get the URL for a request.
Parameters:
-
params
Object
Returns:
-
String
- URL
coalesceFindRequests{boolean}
By default the RESTAdapter will send each find request coming from a store.find
or from accessing a relationship separately to the server. If your server supports passing ids as a query string, you can set coalesceFindRequests to true to coalesce all find requests within a single runloop.
For example, if you have an initial payload of:
{ post: { id: 1, comments: [1, 2] } }
By default calling post.get('comments')
will trigger the following requests(assuming the comments haven't been loaded before):
GET /comments/1 GET /comments/2
If you set coalesceFindRequests to true
it will instead trigger the following request:
GET /comments?ids[]=1&ids[]=2
Setting coalesceFindRequests to true
also works for store.find
requests and belongsTo
relationships accessed within the same runloop. If you set coalesceFindRequests: true
store.findRecord('comment', 1); store.findRecord('comment', 2);
will also send a request to: GET /comments?ids[]=1&ids[]=2
Note: Requests coalescing rely on URL building strategy. So if you override buildURL
in your app groupRecordsForFindMany
more likely should be overridden as well in order for coalescing to work.
headers{Object}
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. For dynamic headers see headers customization.
app/adapters/application.js
import DS from 'ember-data'; export default DS.RESTAdapter.extend({ headers: { 'API_KEY': 'secret key', 'ANOTHER_HEADER': 'Some header value' } });
host{String}
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' });
Requests for the Post
model would now target https://api.example.com/post/
.
namespace{String}
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 Post
model would now target /api/1/post/
.
© 2017 Yehuda Katz, Tom Dale and Ember.js contributors
Licensed under the MIT License.
https://emberjs.com/api/data/classes/DS.RESTAdapter.html