How to run fastlane screenshots in CI on a Mac

Screenshot capture needs a Mac: iOS screenshots come from simulators, and Xcode runs only on macOS. kinhin provides that Mac as a runner, and the workflow runs the screenshots lane on it. The VM is deleted when the job ends, so the workflow also uploads the PNGs as an artifact. Without that step the screenshots disappear with the VM.

Steps

1. Set up the fleet. Install kinhin and start the runner as in How to run GitHub Actions on a self-hosted Mac.
2. Add the screenshot settings. Set the repository variables under Settings, then Secrets and variables, then Variables. SNAPSHOT_LANGUAGES sets the iOS languages and defaults to en-US.
3. Run the lane by hand. Start the mobile workflow and choose screenshots as the lane.
4. Download the screenshots. When the run finishes, open its page and download the ios-screenshots artifact. It is kept for 14 days.

The artifact is visible to everyone who can read the workflow run. Use test accounts and fake data on the screens the lane captures.

What has been verified

The iOS lane has been run locally on a simulator. The Android job needs an Android emulator on the runner, and the runner image has to provide it. That setup has not been verified on a runner yet.

The Store screenshots page has every workflow variable and the artifact details.

Next steps

• Quick start: From zero to a working fleet
• Install: Pinned versions, updates and uninstall
• Forge support: What has been run against a real server
• Why kinhin: Why most runners do one job at a time