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Scaffolding

Objective: To create the initial project structure for our provider. Learn about the scaffolding tooling. NOTE: these steps are applicable to any operator you want to build.

  1. Open your favourite terminal and go to cluster-api-provider-docker directory.
  2. Run the following commands to scaffold the project
kubebuilder init --domain  cluster.x-k8s.io --repo github.com/myname/cluster-api-provider-docker --project-version 3
  1. Run the following commands to scaffold the API & controllers for the DockerCluster and DockerMachine, ensuring you answer Y to the following: a. Create Resource b. Create Controller
kubebuilder create api --group infrastructure --version v1alpha1 --kind DockerCluster
kubebuilder create api --group infrastructure --version v1alpha1 --kind DockerMachine

If you get the following error:

/usr/local/go/src/net/cgo_linux.go:12:8: no such package located

Then you should install gcc and set the CGO_ENABLED environment variable to 0 to disable cgo

  1. Run the following commands:
make generate
make manifests
make build

  1. Take a look at the generated code:

    1. api/v1alpha1 folder contains the CRD definitions for your infrastructure cluster & machine
    2. controllers contains the controllers that will reconcile instances of your infrastructure CRDs
    3. config contains the Kubernetes artifacts that will be bundled together and used when deploying our provider

  2. Make a change to main.go change the port for the health-probe-bind-address flag from 8081 to 9440:

flag.StringVar(&probeAddr, "health-probe-bind-address", ":9440", "The address the probe endpoint binds to.")

This change is required as the liveness/readiness probes get generated using port 9440 but the code uses 8081 by default. If you don't change this then when you deploy the liveness and readiness probes will fail