Set up Mattermost notifications using the discourse-chat-integration plugin

(David Taylor) #1

This #howto describes how to setup the Mattermost provider included in discourse-chat-integration.


If you haven’t already, install the discourse-chat-integration plugin


Set up Mattermost

Your Mattermost server needs to be accessible from your Discourse server in order to connect them. It is recommended that you use HTTPS, but HTTP should also work.

  1. In your Mattermost System Console, under Custom Integrations, check that these settings are enabled:

    • Enable Incoming Webhooks
    • Enable integrations to override usernames
    • Enable integrations to override profile picture icons
    • Enable Custom Slash Commands (if you want slash commands)
  2. Login to your team, click your name in the top left, then click Integrations

  3. Choose Incoming Webhooks, Add incoming Webhook

  4. Enter a “Display Name”, “Description”, and choose a random channel from the list (it doesn’t matter which one, Discourse will override this)

  1. Save

  2. Copy the URL provided, you’ll need it later

Setup Discourse

  1. Paste the URL you copied into the chat_integration_mattermost_webhook_url site setting

  2. Enable chat_integration_mattermost_enabled

  3. Setup some “Rules” for your channels, according to the discourse-chat-integration instructions. Channel identifiers look like #town-square or @davidtaylor.

  4. Click Test on one of the channels to check everything’s working. You should receive a message like this:

  5. :unicorn:

Slash Commands

Slash commands allow you to manage your rules from inside Mattermost. To get it working:

  1. If you didn’t already, enable Enable Custom Slash Commands in your Mattermost System Console

  2. Login to your team, click your name in the top left, then click Integrations

  3. Choose Slash Commands, Add slash command

    • Display Name: Discourse
    • Description: Manage Discourse notification rules
    • Command Trigger Word: discourse
    • Request URL: <your-discourse-url>/chat-integration/mattermost/command
    • Request Method: POST
    • Response Username: Discourse
    • Response Icon: (optionally specify an icon URL)
    • Autocomplete: :ballot_box_with_check:
    • Autocomplete Hint: Manage this channel's integration with Discourse
    • Autocomplete Description: [watch|follow|mute|delete|status|help]
  4. Save

  5. Copy the “Token” provided, and paste it into your Discourse site settings under chat_integration_mattermost_incoming_webhook_token

  6. Try sending /discourse help in your mattermost channel - you should get a message with a list of possible commands

  7. :1st_place_medal:

Mattermost: Post notifications to chat, post transcripts to forum
(Sam Saffron) #2

I recommend you also post this on the mattermost Discourse to get more feedbacks :cowboy_hat_face:

and probably a dedicated topic.

(also I wish we warned communities about hideous looking oneboxes cause they are missing images)

(Régis Hanol) #3

I think we already do in the dashboard if they use the default images for the logos.

(David Taylor) #4

Mattermost integration now supports slash commands (their implementation is built to be compatible with Slack’s) :tada:

I have also created a topic about it on the Mattermost forum, it can be found here:


Hello! I am getting a broken image link to the right of the mattermost post. I tried to see the image url and it looks like an actual post instead of an image:

Is it intended to be the post author image I wonder?

Any tips on how to fix it?

(David Taylor) #6

Hi @nommaz - sorry about that. It was indeed trying to load an image from the URL of the post, which clearly isn’t going to work :wink:

I’ve fixed it now, so if you update to the latest version of the plugin it should work as intended :slight_smile:


Hi David didnt work unfortunately

Are you sure it is not an issue with mattermost_provider.rb:68 ?



(David Taylor) #8

Oops, I made the change in the slack provider instead of mattermost :facepalm:

Just added another commit to correct the error, so please can you give it another try :slight_smile:


Thanks! All set now :slight_smile:

(Syscoin Community) #10

What’s up if I get a 422 error when trying (test) to hook to Mattermost?

(David Taylor) #11

Make sure you copied the webhook URL correctly, and that there are no spaces before/after the URL. Is your mattermost server accessible to the internet? Or just an internal network?