mod_slack_webhooks

Introduction

This module provides a Slack-compatible “web hook” interface to Prosody MUCs. Both “incoming” web hooks, which allow Slack integrations to post messages to Prosody MUCs, and “outgoing” web hooks, which copy messages from Prosody MUCs to Slack-style integrations by HTTP, are supported. This can also be used, in conjunction with various Slack inter-namespace bridging tools, to provide a bidirectional bridge between a Prosody-hosted XMPP MUC and a Slack channel.

Usage

First copy the module to the prosody plugins directory.

Then add “slack_webhooks” to your modules_enabled list:

Component "conference.example.org" "muc"
modules_enabled = {
  "slack_webhooks",
}

Configuration

The normal use for this module is to provide an incoming webhook to allow integrations to post to prosody MUCs:

incoming_webhook_path = "/msg/DFSDF56587658765NBDSA"
incoming_webhook_default_nick = "Bot" -- Unless otherwise specified, posts as "Bot"

This allows Slack-style JSON messages posted to http://conference.example.org/msg/DFSDF56587658765NBDSA/chat to appear in the MUC chat@conference.example.org. A username field in the message is honored as the nick attached to the message; if no username is specified, the message will use the value of default_from_nick. Specifying a string of random gibberish in the URL is important to prevent spam.

In addition, there is a second operating mode equivalent to Slack’s outgoing webhooks. This allows all messages from a set of specified chat rooms to be routed to an external server over HTTP in the format used by Slack’s outgoing webhooks.

outgoing_webhook_routing = {
    -- Send all messages from chat@conference.example.org to
    -- a web server.
    ["chat"] = "http://example.org/cgi-bin/messagedest",
}

Known Issues

The users from whom messages delivered from integrations are apparently delivered are not, in general, members of the MUC. Other prosody modules that try to look up information about the users who most messages, mostly logging modules, may become confused and fail (clients all work fine because replayed history also can come from non-present users). In at least some cases, such as with mod_muc_mam, this can be fixed by hiding the JIDs of the participants in the room configuration.

There are a few smaller UI issues:

• If an integration posts with the same username as a room member, there is no indication (like Slack’s [bot] suffix) that the message is not from that room member.
• It is not currently possible to prevent posting to some MUCs (this is also true of Slack).
• It should be possible to set the webhook configuration for a room in the room configuration rather than statically in Prosody’s configuration file.

Compatibility

sudo prosodyctl install --server=https://modules.prosody.im/rocks/ mod_slack_webhooks