Slack bot fails to send message to restricted general channel via chat.postMessage

Question

This is my first time trying to create a slack bot and I am following this template code to the word, I have not made any changes, and just remixed on glitch, copy-pasted the auth tokens correctly, things worked just fine. That is until I made the #general channel restricted for Full Member users.

This is the error I see in the logs at glitch.

PostMessage Error: restricted_action

Is there an additional scope that I need to set, other than bot ?

Here is the workspace user permissions, I am the owner for this workspace.

Here is the code:

const postAnnouncementToChannel = (user, announcement) => {
  const { title, details, channel } = announcement;

  let announcementData = {
    token: process.env.SLACK_ACCESS_TOKEN,
    channel: channel,
    text: `:loudspeaker: Announcement from: <@${user}>`,
    attachments: JSON.stringify([
      {
        title: title,
        text: details,
        footer: 'DM me to make announcements.'
      }
    ])
  };
  send(announcementData, user);
}


const send = async(data) => { 
  data.as_user = true; // send DM as a bot, not Slackbot
  const result = await axios.post(`${apiUrl}/chat.postMessage`, qs.stringify(data))
  try {
    if(result.data.error) console.log(`PostMessage Error: ${result.data.error}`);
  } catch(err) {
    console.log(err);
  }
}

Testing it via

https://api.slack.com/methods/chat.postMessage/test using bot-token says

{
    "ok": false,
    "error": "restricted_action"
}

Testing this using xoxp-token gives this:-

{
    "ok": false,
    "error": "missing_scope",
    "needed": "chat:write:user",
    "provided": "identify,bot"
}

Answer 1

No. You are not missing any scopes. Its just that the user you used to auth your app can not post into the general channel. Apparently admins have restricted who can post messages in that channel, e.g. to admins only.

Either use a user that has posting rights for that channel to auth your app or switch to a different channel for your testing.