Confluence API: How do I get the author of a comment?

Hey @ClaudioCicali, sorry for bumping an old thread but I ended up here after also trying to get comment authors from the Confluence API.

It’s possible to retrieve the comment author by including the history parameter to expand. The resulting payload contains a history object in each comment which looks like this:

"history": {
    "createdBy": {
        "type": "known",
        "accountId": "<accountId>",
        "accountType": "atlassian",
        "email": "<email>",
        "displayName": "<display name>",
        "isExternalCollaborator": false,
    },
    "createdDate": "2021-11-14T12:26:46.248Z",
}

I believe the issue with your query is that the expand parameter should contain a comma-separated list of items to expand, so instead of ?expand=body.export_view&history.contributors it should be ?expand=body.export_view,history.contributors

(or in this case ?expand=body.export_view,history should suffice)