HTTP Status 202 (Accepted)

HTTP Status 202 indicates that request has been accepted for processing, but the processing has not been completed. This status code is useful when actual operation is asynchronous in nature.

Its purpose is to allow a server to accept a request for some other process (perhaps a batch-oriented process that is only run once per day) without requiring that the user agent’s connection to the server persist until the process is completed.

The entity returned with this response SHOULD describe the request’s current status and point to (or embed) a status monitor that can provide the user with (or without) an estimate of when the request will be fulfilled.

HTTP Status 202 (Accepted) – Example

If you submitted a long running asynchronous job to an REST API then API can return the result like this:

HTTP STATUS 202 (Accepted)

{
	"task": {
		"href": "/api/company/job-management/jobs/2130040",
		"id": "2130040"
	}
}

Now user agent can send HTTP GET request to URI /api/company/job-management/jobs/2130040 periodically for completion status of the job. The response of above API will inform the current status of actual scheduled operation.

Job Not Started

{
   "job" : {
     "@uri" : "/api/company/job-management/jobs/2130040" ,
     "id" : "2130040",
     "name" : "Update Resource",
     "job-state" : "SCHEDULED",
     "job-status" : "UNDETERMINED",
     "percent-complete" : "0",
     "scheduled-start-time" : "01-01-2013 10:50:45 PM GMT",
     "start-time" : "",
     "end-time" : "",
     "owner" : "Admin",
     "summary" : "random text" 
   }
}

Job Started

{
   "job" : {
     "@uri" : "/api/company/job-management/jobs/2130040" ,
     "id" : "2130040",
     "name" : "Update Resource",
     "job-state" : "STARTED",
     "job-status" : "INPROGRESS",
     "percent-complete" : "30",
     "scheduled-start-time" : "01-01-2013 10:50:45 PM GMT",
     "start-time" : "01-01-2013 10:50:55 PM GMT",
     "end-time" : "",
     "owner" : "Admin",
     "summary" : "random text" 
   }
}

Job Completed

{
   "job" : {
     "@uri" : "/api/company/job-management/jobs/2130040" ,
     "id" : "2130040",
     "name" : "Update Resource",
     "job-state" : "COMPLETED",
     "job-status" : "SUCCESS",
     "percent-complete" : "100",
     "scheduled-start-time" : "01-01-2013 10:50:45 PM GMT",
     "start-time" : "01-01-2013 10:50:55 PM GMT",
     "end-time" : ""01-01-2013 10:52:18 PM GMT",
     "owner" : "Admin",
     "summary" : "random text" 
   }
}

Above example is for reference only.

Reference: HTTP Status 202 (Accepted)