Problem Definition

When there are datetime fields as a result from a REST API GET request, time is shown on the timezone configured on the Jira backend server.
For example GET /rest/api/latest/index/summary:

{
    "nodeId": "mycluster1",
    "reportTime": "2024-08-28T11:12:50.619+0000",
    "issueIndex": {
        "indexReadable": true,
        "countInDatabase": 23,
        "countInIndex": 23,
        "countInArchive": 0,
        "lastUpdatedInDatabase": "2024-08-27T11:19:12.904+0000",
        "lastUpdatedInIndex": "2024-08-27T11:19:12.000+0000"
    }
}

The timezone configured on the user profile doesn't make a difference to this output.

On the GET /rest/api/latest/issue/<key>, the output from the fields list uses the Jira backend timezone as well.
There's a possibility to use GET /rest/api/latest/issue/<key>?expand=renderedFields which will show time on the timezone chosen on the user profile within the renderedFields list.

Suggested Solution

It would be great having this type of details on the Jira Server platform REST API reference.