DigitalGuards shared GitHub tooling

Release announcements for Discord

actions/release-discord posts a published GitHub release to a Discord channel as one message: a heading with the project name and tag, the release notes, and a link to the release page for downloads. The message is plain Markdown content, so it can be forwarded to another server or copied as text.

Setup in a repository

1. Store the channel's Discord webhook URL as the repository secret DISCORD_RELEASE_WEBHOOK. A webhook URL that ends in /github (the form GitHub repository webhooks use) works as is.
2. Copy examples/release-announcement.yml to .github/workflows/release-announcement.yml, set project, and replace <commit-sha> with the full commit SHA of the tag release-discord-v1 (git rev-parse release-discord-v1^{commit}).

The action runs with the webhook secret in its environment, so callers pin it to a commit SHA. A later push to this repository changes nothing until a caller moves its pin.

For a release event GitHub reads the workflow from the tagged commit, so the file has to be on the branch releases are tagged from. Releases created with the workflow GITHUB_TOKEN trigger no workflows at all; releases cut by hand or with a personal token do.

Writing the notes

• The whole release body is posted when it has no markers.
• A block between <!-- discord --> and <!-- /discord --> is posted in place of the body. Use it for a community announcement next to technical notes such as checksums and validation logs.
• Discord caps a message at 2000 characters. The heading and the link take about 150, and longer notes are cut at a paragraph with a pointer to the release page.
• Headings move below the message title, images and HTML are dropped, #123 and GitHub pull request URLs become links, and code is kept as written.
• Mentions never ping: @everyone and user or role mentions are posted as plain text.

Running it by hand

Run the workflow from the Actions tab with a tag to announce an existing release again. Tick dry-run to print the message in the job log instead of posting it. Prereleases are announced from a manual run, and from the release event only with prereleases: true.

Tests

cd actions/release-discord && python3 -m unittest -v test_announce