Mastodon

Lets users post to Mastodon. The adapter’s setup registers the app on a Mastodon server, so there’s no console to visit.

Last checked against the Mastodon API: 2026-10-22.

Requirements

A Mastodon server running 4.4 or newer: see version at https://<SERVER>/api/v2/instance
An HTTPS redirect URI

The adapter serves one Mastodon server: only accounts on that server can link.

Configure the adapter

sudo ./publisher.sh platforms add \
  https://github.com/smswithoutborders/mastodon-oauth2-adapter
sudo ./publisher.sh platforms setup mastodon \
  --input client_name=RelaySMS \
  --input redirect_uris=https://example.com/callback \
  --input website=https://example.com \
  --input base_url=https://mastodon.social

Input	Required	Description
`client_name`	Yes	App name on the server’s consent page
`redirect_uris`	Yes	Comma-separated redirect URIs your apps send, the default first
`website`	No	Home page on the consent page
`base_url`	No	The server. Default: `https://mastodon.social`

setup registers the app with the scopes profile, write:statuses and write:media, and saves its client ID and secret. Run it again to change the redirect URIs or the server; it registers a new app and replaces every setting. After changing the server, users must link again.

Check it

sudo ./publisher.sh platforms config show mastodon

You should see client_secret as (secret, set).

Troubleshooting

A user can’t link

Their account is on another server than base_url.

Linking fails after authorizing

The server runs Mastodon older than 4.4.

“The redirect URI included is not valid”

The app sent a URI the app registration doesn’t have. Run setup again with it.

RelaySMS Publisher