Purpose

Install Docker and optionally start/enable the daemon on Linux runners.

Location

setup/runner/install-docker.sh

Preconditions

• Required tools: bash, package manager, optional sudo, optional systemctl
• Required permissions: package install privileges; service management for daemon actions
• Required environment variables: none

Arguments

Scenarios

• Happy path: Docker installed and daemon started (Linux).
• Common operational path: install binary only in immutable environments.
• Failure path: missing package manager or insufficient privileges.
• Recovery/rollback path: fix package/service permissions and rerun.

Usage

setup/runner/install-docker.sh --yes --update-cache
setup/runner/install-docker.sh --manager apt --no-start-service
setup/runner/install-docker.sh --add-user-to-docker-group

Behavior

• Main execution flow: detect manager, install package if needed, manage service/group options.
• Idempotency notes: skip install when docker already exists.
• Side effects: package install, daemon state changes, optional group membership changes.

Output

• Standard output format: timestamped progress logs.
• Exit codes:
• 0 success
• 1 install/runtime failure
• 2 invalid arguments

Failure Modes

• Common errors and likely causes:
• unsupported manager selection
• package not found in repositories
• no permission for service/group updates
• Recovery and rollback steps:
• verify repositories and package availability
• rerun with elevated privileges where required

Security Notes

• Secret handling: none.
• Least-privilege requirements: avoid unnecessary root usage outside install/service steps.
• Audit/logging expectations: record daemon/group changes for compliance.

Testing

• Unit tests:
• manager detection and option validation
• Integration tests:
• install/start behavior on Linux/macOS test images
• Manual verification:
• docker --version and docker info