Error connecting to Zapier

Summary

Adding an OAuth2 connection to zapier produces “invalid_request: Supplied redirect_uri did not match registered callback_url

Steps to reproduce

  1. On a Mattermost Team docker installation, from the Mattermost System Console enable incoming webhooks, outgoing webhooks, custom slash commands, OAuth 2.0 service provider,

  2. Then from the Integrations menu for my team, create a new OAuth 2.0 application for Zapier, following the directions at https://docs.mattermost.com/integrations/zapier.html#register-zapier-as-an-oauth-2-0-application, using callback URL https://zapier.com/dashboard/auth/oauth/return/MattermostDevAPI/

  3. Next, at Zapier, create a new connected account for Mattermost, providing my Mattermost server URL with no trailing slash, the client ID and client secret copied from the Mattermost integration.

  4. Click “Yes, continue,”

Expected behavior

Successful registration of the connected account.

Observed behavior

Error message from my mattermost server: “invalid_request: Supplied redirect_uri did not match registered callback_url

The log (on debug setting) shows

{"level":"debug","ts":1545597347.7134793,"caller":"web/handlers.go:50","msg":"GET - /oauth/authorize"}
{"level":"debug","ts":1545597347.8739557,"caller":"web/handlers.go:50","msg":"GET - /error"}
{"level":"debug","ts":1545597348.4264553,"caller":"web/handlers.go:50","msg":"GET - /api/v4/config/client"}
{"level":"debug","ts":1545597348.426538,"caller":"web/handlers.go:50","msg":"GET - /api/v4/license/client"}
{"level":"debug","ts":1545597348.4576566,"caller":"web/handlers.go:50","msg":"GET - /api/v4/users/me"}
{"level":"debug","ts":1545597348.4589357,"caller":"web/handlers.go:50","msg":"GET - /api/v4/users/me/preferences"}
{"level":"debug","ts":1545597348.5027037,"caller":"web/handlers.go:50","msg":"GET - /api/v4/users/me/teams"}
{"level":"debug","ts":1545597348.5081077,"caller":"web/handlers.go:50","msg":"GET - /api/v4/users/me/teams/members"}
{"level":"debug","ts":1545597348.5148346,"caller":"web/handlers.go:50","msg":"GET - /api/v4/users/me/teams/unread"}
{"level":"debug","ts":1545597348.5615678,"caller":"web/handlers.go:50","msg":"GET - /api/v4/plugins/webapp"}
{"level":"debug","ts":1545597350.0335193,"caller":"web/handlers.go:50","msg":"GET - /api/v4/logs"}

Thank you @jonathan-g for the report! I’ve reproduced the error and created a ticket for our engineers.

I’m not yet sure if this is an issue related to our Zapier app, or something on the Mattermost server that’s causing it.

https://mattermost.atlassian.net/browse/MM-13596

1 Like

Hey @jonathan-g - this doesn’t appear to be reproducing anymore, so it might have been a temporary error on Zapier’s side.

Would you be open to trying again if it still occurs for you?

This works now. Thanks for looking into it.