Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
End-to-End Zero Downtime: Deploying Bookstore with Blue-Green and Canary via GitHub Actions
All pieces of the series in a single GitHub Actions workflow: build the image once, a migration gate and an expand migration bundle, deploy to the idle color, a smoke test through the preview, 10% and 50% canary gates, a full switch and a manual rollback job. Run locally with act, the pipeline failed four times before succeeding: a gate scanning Down(), act's artifact v7 incompatibility, a preview pointing at the old color, and too little canary traffic.
GitHub Actions Triggers: push, pull_request, workflow_dispatch, schedule and Filters
The events and filters under on decide when a workflow runs: branches, tags, paths and ! negation for push and pull_request, activity types, workflow_dispatch inputs, timezone-aware schedules, workflow_run, repository_dispatch and merge_group. With real output we show the trap of reading booleans via github.event.inputs, the trigger mistakes actionlint catches, and why act does not evaluate filters.
What Is GitHub Actions? Your First CI with Workflows, Events, Jobs, Steps and Runners
GitHub Actions is a CI/CD platform that runs the YAML workflows under .github/workflows on runners in response to repository events. We write a first workflow that restores, builds and unit-tests the Bookstore API, try it locally with act and actionlint, and cover uses versus run, the run log, re-runs and the reasoning behind the Web API 31 workflow.