How do I configure the button in my Interactive Message to make a request to a third party REST API?

Troubleshooting
1 
{
  "attachments": [
    {
      "pretext": "This is the attachment pretext.",
      "text": "This is the attachment text.",
      "actions": [
        {
          "id": "message",
          "name": "Ephemeral Message",
          "integration": {
            "url": "http://127.0.0.1:7357",
            "context": {
              "action": "do_something_ephemeral"
            }
          }
        }, {
          "id": "update",
          "name": "Update",
          "integration": {
            "url": "http://127.0.0.1:7357",
            "context": {
              "action": "do_something_update"
            }
          }
        }
      ]
    }
  ]
}

In the documentation for Message Button of Interactive Message for Mattermost, it was stated that the value in action of context is to do something, but I don’t understand how to replace that part to trigger the call to the URL I provided for the button.

However, my use case is to make the button make a request to a third party API. But I do not know how to configure that. Need some advices on this matter…

If possible, can share some of the existing integration (source code) of Interactive Message in your services/projects?