Masto Feed Bot

Masto Feed Bot is a GitHub Action that posts RSS/ATOM feeds to Mastodon via GitHub Actions workflows.

Usage

1. Go to https://${YOUR_INSTANCE}/settings/applications/new and add a new application.

   • Name it whatever you want.
   • The redirect URI is not important, so you can use urn:ietf:wg:oauth:2.0:oob.
   • The only permission required is write:statuses.
   • Save it, click on the application link, and grab the access token.

2. Create a new GitHub repository.

3. Go to your repository settings at https://github.com/${YOUR_REPO}/settings/secrets/actions/new, and add a new secret with the value of the access token.

4. Add a file named .github/workflows/mastofeedbot.yml with the following content:

   name: FeedBot
   on:
     schedule:
       # This will run every five minutes. Alter it using https://crontab.guru/.
       - cron: '*/5 * * * *'
   jobs:
     rss-to-mastodon:
       runs-on: ubuntu-latest
       steps:
         - name: Generate cache key
           uses: actions/github-script@v7
           id: generate-key
           with:
             script: |
               core.setOutput('cache-key', new Date().valueOf())
         - name: Retrieve cache
           uses: actions/cache@v4
           with:
             path: ${{ github.workspace }}/mastofeedbot
             key: feed-cache-${{ steps.generate-key.outputs.cache-key }}
             restore-keys: feed-cache-
         - name: GitHub
           uses: 'joschi/mastofeedbot@v1'
           with:
             # This is the RSS feed you want to publish
             rss-feed: https://www.githubstatus.com/history.rss
             # Template of status posted to Mastodon (Handlebars)
             template: |
               {{item.title}}
               
               {{item.link}}
             # Visibility of the posted status (public | unlisted | private | direct)
             status-visibility: public
             # Mark Mastodon status as sensitive content
             sensitive: false
             # This is your instance address
             api-endpoint: https://mastodon.social
             # This is the secret you created earlier
             api-token: ${{ secrets.MASTODON_ACCESS_TOKEN }}
             # This is a path to the cache file, using the above cache path
             cache-file: ${{ github.workspace }}/mastofeedbot/cache.json
             # The maximum number of posts created on the first run
             initial-post-limit: 10

5. Commit and publish your changes.

Inputs

Input	Required	Default	Description
rss-feed	✅		RSS/ATOM feed URL
api-endpoint	✅		Mastodon instance URL (e.g. https://mastodon.social)
api-token	✅		Mastodon access token
cache-file	✅		Path to the cache file
template		{{item.title}} {{item.link}}	Handlebars template for the posted status
status-visibility		public	Visibility of the posted status (public | unlisted | private | direct)
sensitive		false	Mark Mastodon status as sensitive content
dry-run		false	Fetch feed and update cache but skip posting to Mastodon
cache-limit		100	Maximum number of items to keep in the cache
initial-post-limit		unlimited	Maximum number of posts created on the first run (when no cache file exists)
post-limit		unlimited	Maximum number of posts created per run
xml-entity-expansion-limit		10000	Maximum number of entity expansions allowed when parsing the RSS feed XML. Set to 0 to disable entity expansion processing entirely.

Status template

The status template (template) is using Handlebars as template engine.

The action passes the feed metadata as feedData (type FeedData) and the current entry as item (type FeedEntry) into the template:

export interface FeedEntry {
  id: string;
  link?: string;
  title?: string;
  description?: string;
  published?: string; // ISO 8601 date string
}

export interface FeedData {
  link?: string;
  title?: string;
  description?: string;
  generator?: string;
  language?: string;
  published?: string; // ISO 8601 date string
  entries?: Array<FeedEntry>;
}