How to change mediaType of attachment with REST API?

[Nick Irvine]

Here's what I'm trying:

curl -n -Ss -X PUT -H 'X-Atlassian-Token: nocheck' '-d{"metadata": {"mediaType": "image/svg+xml" }' https://xxx.atlassian.net/wiki/rest/api/content/26509481/child/attachment/att26869829

This yields: HTTP Status 415 - Unsupported Media Type

Both the PUT /rest/api/content/{id}/child/attachment/{attachmentId} (after uploading) and POST /rest/api/content/{id}/child/attachment/{attachmentId}/data (while uploading) endpoints claim to be able to update the media type (although it confusingly switches between the media-type and content-type terminology), but neither give any indication of how to do so.

Another method I've tried is setting the Content-Type HTTP header to "image/svg+xml", but this is rejected with an "invalid media type" error.

I can update using the UI just fine.

I also tried the REST API Browser, but like all useful parts of Confluence, it's not available on a cloud install >:[

[Neil Russell · Accepted solution]

The error message you are getting is because you are not setting the Content Type header for the PUT request to application/json. You need to add -H 'Content-Type: application/json' to your curl request. I've included an example below. 

curl -n -u admin:admin -X PUT -H 'Content-Type: application/json' -H 'X-Atlassian-Token: nocheck' -d '{"id":"att917507", "version":{"number":1}, "metadata": {"mediaType": "image/svg+xml" }}' http://localhost:1990/confluence/rest/api/content/98310/child/attachment/att917507

[Nick Irvine]

That's probably it. I can't test any more, but have a checkmark.

[LostInMadness Forever]

here is my code to upload an image.. i got 415 status, meaning bad content-type

of course, i longon first using "auth/1/session"

here to upload..

file = "C:\Users\User\Documents\file.jpg"

oRequest.Open("POST", jiraURL)
oRequest.SetRequestHeader("X-Atlassian-Token", "no-check")

oRequest.SetRequestHeader("Content-Disposition", "form-data; name=""file""; filename=""file.jpg""")
oRequest.SetRequestHeader("Content-Type", "image/jpeg; boundary=WebKitFormBoundaryE19zNvXGzXaLvS5C")

oRequest.Send(file)