An extension which provides a RESTful XHR sync implementation that can be mixed into a Model or ModelList subclass.
This makes it trivial for your Model or ModelList subclasses communicate and
transmit their data via RESTful XHRs. In most cases you'll only need to provide
a value for root
when sub-classing Y.Model
.
Y.User = Y.Base.create('user', Y.Model, [Y.ModelSync.REST], {
root: '/users'
});
Y.Users = Y.Base.create('users', Y.ModelList, [Y.ModelSync.REST], {
// By convention Y.User
's root
will be used for the lists' URL.
model: Y.User
});
var users = new Y.Users();
// GET users list from: "/users"
users.load(function () {
var firstUser = users.item(0);
firstUser.get('id'); // => "1"
// PUT updated user data at: "/users/1"
firstUser.set('name', 'Eric').save();
});
_joinURL
url
Joins the root
URL to the specified url
, normalizing leading/trailing
"/" characters.
url
String
URL to append to the root
URL.
Joined URL.
model.root = '/foo'
model._joinURL('bar'); // => '/foo/bar'
model._joinURL('/bar'); // => '/foo/bar'
model.root = '/foo/'
model._joinURL('bar'); // => '/foo/bar/'
model._joinURL('/bar'); // => '/foo/bar/'
_onSyncIOEnd
txId
details
Called when the Y.io
request has finished, after "success" or "failure"
has been determined.
This is a no-op by default, but provides a hook for overriding.
_onSyncIOFailure
txId
res
details
Called when the Y.io
request has finished unsuccessfully.
By default this calls the details.callback
function passing it the HTTP
status code and message as an error object along with the response body.
_onSyncIOStart
txId
details
Called when the Y.io
request is made.
This is a no-op by default, but provides a hook for overriding.
_onSyncIOSuccess
txId
res
details
Called when the Y.io
request has finished successfully.
By default this calls the details.callback
function passing it the
response body.
_parse
response
Calls both public, overrideable methods: parseIOResponse()
, then parse()
and returns the result.
This will call into parseIOResponse()
, if it's defined as a method,
passing it the full response object from the XHR and using its return value
to pass along to the parse()
. This enables developers to easily parse data
out of the response headers which should be used by the parse()
method.
response
Object
Response object from Y.io()
.
_sendSyncIORequest
config
Performs the XHR and returns the resulting Y.io()
request object.
This method is called by sync()
.
config
Object
An object with the following properties:
action
String
The sync()
action being performed.
[callback]
Function
optional
Called when the sync operation finishes.
[entity]
String
optional
The HTTP request entity body.
headers
Object
The HTTP request headers.
method
String
The HTTP request method.
[timeout]
Number
optional
Time until the HTTP request is aborted.
url
String
The URL of the HTTP resource.
The resulting Y.io()
request object.
_substituteURL
url
data
Utility which takes a tokenized url
string and substitutes its
placeholders using a specified data
object.
This method will property URL-encode any values before substituting them. Also, only expect it to work with String and Number values.
Substituted URL.
var url = this._substituteURL('/users/{name}', {id: 'Eric F'});
// => "/users/Eric%20F"
getURL
[action]
[options]
Returns the URL for this model or model list for the given action
and
options
, if specified.
This method correctly handles the variations of root
and url
values and
is called by the sync()
method to get the URLs used to make the XHRs.
You can override this method if you need to provide a specific implementation for how the URLs of your Model and ModelList subclasses need to be generated.
this model's or model list's URL for the the given
action
and options
.
parseIOResponse
response
Called to parse the response object returned from Y.io()
. This method
receives the full response object and is expected to "prep" a response which
is suitable to pass to the parse()
method.
By default the response body is returned (responseText
), because it
usually represents the entire entity of this model on the server.
If you need to parse data out of the response's headers you should do so by
overriding this method. If you'd like the entire response object from the
XHR to be passed to your parse()
method, you can simply assign this
property to false
.
response
Object
Response object from Y.io()
.
The modified response to pass along to the parse()
method.
serialize
[action]
Serializes this
model to be used as the HTTP request entity body.
By default this model will be serialized to a JSON string via its toJSON()
method.
You can override this method when the HTTP server expects a different
representation of this model's data that is different from the default JSON
serialization. If you're sending and receive content other than JSON, be
sure change the Accept
and Content-Type
HTTP_HEADERS
as well.
Note: A model's toJSON()
method can also be overridden. If you only
need to modify which attributes are serialized to JSON, that's a better
place to start.
[action]
String
optional
Optional sync()
action for which to generate the
the serialized representation of this model.
serialized HTTP request entity body.
sync
action
[options]
[callback]
Communicates with a RESTful HTTP server by sending and receiving data via XHRs. This method is called internally by load(), save(), and destroy().
The URL used for each XHR will be retrieved by calling the getURL()
method
and passing it the specified action
and options
.
This method relies heavily on standard RESTful HTTP conventions
action
String
Sync action to perform. May be one of the following:
create
: Store a newly-created model for the first time.delete
: Delete an existing model.read
: Load an existing model.update
: Update an existing model.[options]
Object
optional
Sync options:
[csrfToken]
String
optional
The authenticity token used by the
server to verify the validity of this request and protected against CSRF
attacks. This overrides the default value provided by the static
CSRF_TOKEN
property.
[headers]
Object
optional
The HTTP headers to mix with the default
headers specified by the static HTTP_HEADERS
property.
[timeout]
Number
optional
The number of milliseconds before the
request will timeout and be aborted. This overrides the default provided
by the static HTTP_TIMEOUT
property.
[callback]
Function
optional
Called when the sync operation finishes.
err
Error | Null
If an error occurred, this parameter will contain the error. If the sync operation succeeded, err will be falsy.
[response]
Any
optional
The server's response.
_NON_ATTRS_CFG
Properties that shouldn't be turned into ad-hoc attributes when passed to a Model or ModelList constructor.
Default: ["root", "url"]
CSRF_TOKEN
A request authenticity token to validate HTTP requests made by this extension with the server when the request results in changing persistent state. This allows you to protect your server from Cross-Site Request Forgery attacks.
A CSRF token provided by the server can be embedded in the HTML document and
assigned to YUI.Env.CSRF_TOKEN
like this:
<script>
YUI.Env.CSRF_TOKEN = {{session.authenticityToken}};
</script>
The above should come after YUI seed file so that YUI.Env
will be defined.
Note: This can be overridden on a per-request basis. See sync()
method.
When a value for the CSRF token is provided, either statically or via options
passed to the save()
and destroy()
methods, the applicable HTTP requests
will have a X-CSRF-Token
header added with the token value.
Default: YUI.Env.CSRF_TOKEN
EMULATE_HTTP
Static flag to use the HTTP POST method instead of PUT or DELETE.
If the server-side HTTP framework isn't RESTful, setting this flag to true
will cause all PUT and DELETE requests to instead use the POST HTTP method, and
add a X-HTTP-Method-Override
HTTP header with the value of the method type
which was overridden.
Default: false
HTTP_HEADERS
Default headers used with all XHRs.
By default the Accept
and Content-Type
headers are set to
"application/json", this signals to the HTTP server to process the request
bodies as JSON and send JSON responses. If you're sending and receiving content
other than JSON, you can override these headers and the parse()
and
serialize()
methods.
Note: These headers will be merged with any request-specific headers, and the request-specific headers will take precedence.
Default: { "Accept" : "application/json", "Content-Type": "application/json" }
HTTP_METHODS
Static mapping of RESTful HTTP methods corresponding to CRUD actions.
Default: { "create": "POST", "read" : "GET", "update": "PUT", "delete": "DELETE" }
HTTP_TIMEOUT
The number of milliseconds before the XHRs will timeout/abort. This defaults to 30 seconds.
Note: This can be overridden on a per-request basis. See sync()
method.
Default: 30000
root
A string which represents the root or collection part of the URL which relates to a Model or ModelList. Usually this value should be same for all instances of a specific Model/ModelList subclass.
When sub-classing Y.Model
, usually you'll only need to override this
property, which lets the URLs for the XHRs be generated by convention. If
the root
string ends with a trailing-slash, XHR URLs will also end with a
"/", and if the root
does not end with a slash, neither will the XHR URLs.
Default: ""
Y.User = Y.Base.create('user', Y.Model, [Y.ModelSync.REST], {
root: '/users'
});
var currentUser, newUser;
// GET the user data from: "/users/123"
currentUser = new Y.User({id: '123'}).load();
// POST the new user data to: "/users"
newUser = new Y.User({name: 'Eric Ferraiuolo'}).save();
When sub-classing Y.ModelList
, usually you'll want to ignore configuring
the root
and simply rely on the build-in convention of the list's
generated URLs defaulting to the root
specified by the list's model
.
url
A string which specifies the URL to use when making XHRs, if not value is provided, the URLs used to make XHRs will be generated by convention.
While a url
can be provided for each Model/ModelList instance, usually
you'll want to either rely on the default convention or provide a tokenized
string on the prototype which can be used for all instances.
When sub-classing Y.Model
, you will probably be able to rely on the
default convention of generating URLs in conjunction with the root
property and whether the model is new or not (i.e. has an id
). If the
root
property ends with a trailing-slash, the generated URL for the
specific model will also end with a trailing-slash.
Default: ""
Y.User = Y.Base.create('user', Y.Model, [Y.ModelSync.REST], {
root: '/users/'
});
var currentUser, newUser;
// GET the user data from: "/users/123/"
currentUser = new Y.User({id: '123'}).load();
// POST the new user data to: "/users/"
newUser = new Y.User({name: 'Eric Ferraiuolo'}).save();
If a url
is specified, it will be processed by Y.Lang.sub()
, which is
useful when the URLs for a Model/ModelList subclass match a specific pattern
and can use simple replacement tokens; e.g.:
Y.User = Y.Base.create('user', Y.Model, [Y.ModelSync.REST], {
root: '/users',
url : '/users/{username}'
});
Note: String subsitituion of the url
only use string an number values
provided by this object's attribute and/or the options
passed to the
getURL()
method. Do not expect something fancy to happen with Object,
Array, or Boolean values, they will simply be ignored.
If your URLs have plural roots or collection URLs, while the specific item
resources are under a singular name, e.g. "/users" (plural) and "/user/123"
(singular), you'll probably want to configure the root
and url
properties like this:
Y.User = Y.Base.create('user', Y.Model, [Y.ModelSync.REST], {
root: '/users',
url : '/user/{id}'
});
var currentUser, newUser;
// GET the user data from: "/user/123"
currentUser = new Y.User({id: '123'}).load();
// POST the new user data to: "/users"
newUser = new Y.User({name: 'Eric Ferraiuolo'}).save();
When sub-classing Y.ModelList
, usually you'll be able to rely on the
associated model
to supply its root
to be used as the model list's URL.
If this needs to be customized, you can provide a simple string for the
url
property.
Y.Users = Y.Base.create('users', Y.ModelList, [Y.ModelSync.REST], {
// Leverages Y.User
's root
, which is "/users".
model: Y.User
});
// Or specified explicitly...
Y.Users = Y.Base.create('users', Y.ModelList, [Y.ModelSync.REST], {
model: Y.User,
url : '/users'
});