This directory includes a sub directory for every Prow component and is where all binary and container images are built. You can find the main packages here in addition to the BUILD.bazel files that contain Bazel rules for building binary and container images. For details about building the binaries and images see build_test_update.md.
Prow has a microservice architecture implemented as a collection of container images that run as Kubernetes deployments. A brief description of each service component is provided here.
hookis the most important piece. It is a stateless server that listens for GitHub webhooks and dispatches them to the appropriate plugins. Hook's plugins are used to trigger jobs, implement 'slash' commands, post to Slack, and more. See theprow/pluginsdirectory for more information on plugins.plankis the controller that manages the job execution and lifecycle for jobs that run in k8s pods. It is deployed as part of the prow-controller-manager.deckpresents a nice view of recent jobs, command and plugin help information, the current status and history of merge automation, and a dashboard for PR authors.horologiumtriggers periodic jobs when necessary.sinkercleans up old jobs and pods.
tidemanages retesting and merging PRs once they meet the configured merge criteria. See its README for more information.
Hopefully you won't need any of these components...
jenkins-operatoris the controller that manages jobs that run on Jenkins. We moved away from using this component in favor of running all jobs on Kubernetes.totvends sequential build numbers. Tot is only necessary for integration with automation that expects sequential build numbers. If Tot is not used, Prow automatically generates build numbers that are monotonically increasing, but not sequential.sublisten to Cloud Pub/Sub notification to trigger Prow Jobs.
checkconfigloads and verifies the configuration, useful as a pre-submit.mkpjcreatesProwJobsusing Prow configuration.mkpodcreatesPodsfromProwJobs.phonysends fake webhooks for testing hook and plugins.
These are small tools that are automatically added to ProwJob pods for jobs that request pod decoration. They are used to transparently provide source code cloning and upload of metadata, logs, and job artifacts to persistent storage. See their README for more information.
The container images in images are used as base images for Prow components.