Recipients empty when sending transactional message

[keilstefan]

Version:

• listmonk: v2.4.0
• OS: Docker Image

Description of the bug and steps to reproduce:
When posting the following data to the endpoint /api/tx I would expect the recipients sent to the defined messenger endpoint to be filled.

Post to /api/tx

{
    "subscriber_ids": [75],
    "template_id": 9,
    "data": {
        "code": "my_custom_string"
    },
    "messenger": "my_messenger_endpoint",
    "content_type": "plain"
}

Returns:

{
    "data": true
}

The user with the Id "75":

{
  "data": {
    "id": 75,
    "created_at": "2023-05-03T18:27:23.693922Z",
    "updated_at": "2023-05-03T18:27:23.693922Z",
    "uuid": "722d8dcd-63c1-4a66-8f28-27d139474168",
    "email": "[email protected]",
    "name": "Anybody",
    "attribs": {
      "comm_language": "en",
      "comm_methods": [
        {
          "code": "my_code",
          "value": "4711"
        }
      ]
    },
    "status": "enabled",
    "lists": [
      {
        "subscription_status": "confirmed",
        "subscription_created_at": "2023-05-03T18:27:23.693922+00:00",
        "subscription_updated_at": "2023-05-03T18:27:23.693922+00:00",
        "id": 32,
        "uuid": "2732578a-cdcd-4abf-9962-cb33b3b9ceba",
        "name": "list",
        "type": "private",
        "optin": "single",
        "tags": null,
        "created_at": "2022-11-26T19:13:11.926538+00:00",
        "updated_at": "2022-11-26T19:13:11.926538+00:00",
        "description": ""
      }
    ]
  }
}

What I receive at the messenger endpoint is the following:

{
  "subject": "Welcome",
  "content_type": "plain",
  "body": "my template contents",
  "recipients": [
    {
      "uuid": "",
      "email": "",
      "name": "",
      "attribs": "",
      "status": ""
    }
  ],
  "campaign": "null",
  "attachments": "null}",
  "timestamp": "2023-05-03T19:31:54.742Z"
}

What I expect at the messenger endpoint to be received is the following:

{
  "subject": "Welcome",
  "content_type": "plain",
  "body": "my template contents",
  "recipients": [
    {
      "uuid": "722d8dcd-63c1-4a66-8f28-27d139474168",
      "email": "[email protected]",
      "name": "Anybody",
      "attribs": {
        "comm_language": "en",
        "comm_methods": [
          {
            "code": "my_code",
            "value": "4711"
          }
        ]
      },
      "status": "enabled"
    }
  ],
  "campaign": "null",
  "attachments": "null}",
  "timestamp": "2023-05-03T19:31:54.742Z"
}

Is listmonk working as intended? Am I doing something wrong?
Thank you!

[knadh]

Thanks for reporting this @keilstefan. This was a bug.