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Building the memcached-operator with podman and OCP

On this exercise we will go through the issues that I found while trying the example mem-cached operator.

I used the steps from Operator-SDK page and hit issues caused by myself. 🙂 This post is not a step by step from the Tutorial, but how I fixed the issues that I hit.

Pre-requisites

Original instructions for installations => here. But from my testing, at this time of writing were:

  • Binaries 

    $ go version
go version go1.21.10 linux/amd64

$ operator-sdk version
operator-sdk version: "v1.34.2", commit: "81dd3cb24b8744de03d312c1ba23bfc617044005", kubernetes version: "1.28.0", go version: "go1.21.10", GOOS: "linux", GOARCH: "amd64"

$ oc version
Client Version: 4.13.18

$ podman version
Client:       Podman Engine
Version:      4.9.4
API Version:  4.9.4
Go Version:   go1.21.8
Built:        Tue Mar 26 10:41:56 2024
OS/Arch:      linux/amd64

  • Environment 

    OpenShift 4.14.X
Fedora 38

Issue: "Working with personal/private registries"

  • Do podman login to docker.io 
    podman login -u $USER -p "$PASSW" docker.io
  • Update secret from the cluster with the docker.io credentials 
    oc get secret/pull-secret -n openshift-config --template='{{index .data ".dockerconfigjson" | base64decode}}' > ocp-pullsecret.json
oc registry login --registry=docker.io --auth-basic="$USER:$PASSW" --to=ocp-pullsecret.json
oc set data secret/pull-secret -n openshift-config --from-file=.dockerconfigjson=ocp-pullsecret.json

Issue: Back-off pulling image "controller:latest"

Hit back-off pulling image issues, because I mistakenly skipped the step to Setup the Operator Registry 

pod/memcached-operator-controller-manager-6d57548c9f-fdh67    Back-off pulling image "controller:latest"
Failed to pull image "controller:latest": rpc error: code = Unknown desc = reading manifest latest in docker.io/library/controller: requested access to the resource is denied
- Solution: In the file Makefile, set your own registry so the image can be built and pushed automatically to your registry, and then pulled inside the cluster. Eg: 
IMG = docker.io/songbird159/controller:latest

Issue: docker: command not found

Podman have all the equivalent functions as docker, simply use podman to run :) 

make podman-build podman-push

Issue: No rule to make target 'podman-build'

This happens because in the Makefile it is still pointing to be used docker commands, not podman. 

make podman-build podman-push Makefile
make: *** No rule to make target 'podman-build'.  Stop.
- Solution: Replace all docker references to podman. There are about 11 references. 
CONTAINER_TOOL ?= podman
.PHONY: podman-build
podman-build: ## Build docker image with the manager.

.PHONY: podman-push
podman-push: ## Push docker image with the manager.

.PHONY: podman-buildx
podman-buildx:

.PHONY: bundle-build
bundle-build: ## Build the bundle image.
    podman build -f bundle.Dockerfile -t $(BUNDLE_IMG) .

.PHONY: bundle-push
bundle-push: ## Push the bundle image.
    $(MAKE) podman-push IMG=$(BUNDLE_IMG)

catalog-build: opm ## Build a catalog image.
    $(OPM) index add --container-tool podman --mode semver --tag $(CATALOG_IMG) --bundles $(BUNDLE_IMGS) $(FROM_INDEX_OPT)

.PHONY: catalog-push
catalog-push: ## Push a catalog image.
    $(MAKE) podman-push IMG=$(CATALOG_IMG)

Voila!

❯ oc get events --sort-by='{.lastTimestamp}'
Successfully pulled image "docker.io/songbird159/controller:latest" in 3.862300324s (3.86231446s including waiting)

❯ oc get pods -n memcached-operator-system
NAME                                                     READY   STATUS    RESTARTS   AGE
memcached-operator-controller-manager-6d889bb7dd-j4d8q   2/2     Running   0          30m

❯ podman images
REPOSITORY                                      TAG         IMAGE ID      CREATED         SIZE
docker.io/songbird159/controller                latest      4676737e0f28  51 minutes ago  55.4 MB