How to update issue status edit api?

[sbmaggarwal]

I am using 'https://domain.atlassian.net/rest/api/2/issue/{issueIdOrKey}' to edit an issue. I want to use the same API to change the status as well. While following works in edit with PUT method,

{
    "fields":
    {
        "assignee":{"name":"assigneeKey"},
        "priority":{"name":"Highest"},
        "issuetype" : {"name" : "Bug"},
		"summary": "Summary"
    },
    "update": {
			"description": [{
				"set": "Hello description"
			}]
    }
}

'transition' key doesn't work for me. I used it like this 

"transition": {
            "id": "1"}

directly inside the root JSONObject. Server returned with 204 status code but no change was done in Issue.

[Nic Brough -Adaptavist-]

Is transition 1 representing a transition that exists in the workflow?  Is the issue in the right status?  (i.e. the transition is the one that takes it out of that status/step to the desired one?).  Does the workflow have any validators or conditions on it that might be blocking the transtion? (Although I'd expect an error there, rather than a simple 204)

Edit: sorry, that was far too short!  I've tried to improve it.

[sbmaggarwal]

I tried values from 1 to 20 randomly.. None works. I mean I get a 204 No Content response but status doesn't change. To answer your question, 1 is valid.

[Nic Brough -Adaptavist-]

Random numbers really aren't going to do anything!  Could you look at the text view of the workflow?  Especially for the step the issue is currently in?

[Steven F Behnke]

Just a tidbit to add to Nic's great answer, you can use the API to get all transitions and ID's valid for your current state for a specific issue – http://jira.example.com/rest/api/2/issue/TST-123/transitions

The documentation for this REST endpoint is avaliable here – https://docs.atlassian.com/jira/REST/latest/#api/2/issue-getTransitions

Otherwise Nic is right, the correct id value is in the Workflow Editor.