JSONP Policy

Description

This policy turns a standard REST endpoint into a JSONP compatible endpoint. For example, a REST endpoint may typically return the following JSON data:

{
  "foo" : "bar",
  "baz" : 17
}

If the JSONP policy is applied to this API, then the caller must provide a JSONP callback function name via the URL (for details on this, see the Configuration section below). When this is done, the API might respond with this instead:

callbackFunction({
  "foo" : "bar",
  "baz" : 17
})
If the API client does not send the JSONP callback function name in the URL (via the configured query parameter name), this policy will do nothing. This allows managed endpoints to support both standard REST and JSONP at the same time.

Plugin

{
    "groupId": "io.apiman.plugins",
    "artifactId": "apiman-plugins-jsonp-policy",
    "version": "3.1.0-SNAPSHOT"
}

Configuration

The JSONP policy has a single configuration property, which can be used to specify the name of the HTTP query parameter that the caller must use to pass the name of the JSONP callback function.

  • callbackParamName (string) : Name of the HTTP query parameter that should contain the JSONP callback function name.

Sample Configuration

{
   "callbackParamName" : "callback"
}

If the above configuration were to be used, the API client (caller) must send the JSONP callback function name in the URL of the request as a query parameter named callback. For example:

GET /path/to/resource?callback=myCallbackFunction HTTP/1.1
Host: www.example.org
Accept: application/json

In this example, the response might look like this:

myCallbackFunction({
  "property1" : "value1",
  "property2" : "value2"
})