How-to

Publish a slowapp

Let CI check every push, then tag a release to publish your app's image for every hub platform.

A slowapp lives in its own Git repository, named slowapp-<id> by convention, and is published as a container image on GitHub’s registry. The template repository has everything below set up already.

Repository layout

slowapp.toml               the manifest
Dockerfile                 FROM a pinned base image; the manifest goes to /app/slowapp.toml
<module>/                  your code
fixtures/<name>/           test data for each [[example]]
tests/                     unit tests, run inside the base image
.github/workflows/app.yml  calls the shared workflow

The workflow

.github/workflows/app.yml is a few lines that call the shared workflow from slowapp-base:

name: app

on:
  push:
    branches: [main]
    tags: ["v[0-9]+.[0-9]+.[0-9]+"]
  pull_request:
  workflow_dispatch:

jobs:
  app:
    uses: mike-anderson/slowapp-base/.github/workflows/app.yml@v1.0.0
    permissions:
      contents: write
      packages: write

On every push and pull request it:

1. takes the SDK out of the base image your Dockerfile pins, so your app is checked by the tools that match it;
2. checks the manifest and runs your unit tests inside the base image;
3. builds the image and renders every example twice, requiring identical pictures;
4. uploads the previews, and shows the cards and their ids in the run summary;
5. builds the image for 32-bit ARM, the Slowboard 1085’s platform.

Publish a release

Tag a version and push the tag:

git tag v0.1.0 && git push origin v0.1.0

The workflow pushes the image to ghcr.io for linux/arm/v7, linux/arm64 and linux/amd64, and writes the line to pin into the release notes:

image = "ghcr.io/<owner>/slowapp-<id>@sha256:…"

A hub runs an app by digest, never by tag, so a published version can’t change under anyone. To put the release on a hub, see Install a slowapp.

Keep the base image current

The base images release a patch every month with Debian’s security updates. Dependabot opens a pull request in your repository when a new one is out; merge it and tag a new release. Base images explains the versions.