Add aws-s3-csi-controller component (#299)

This is part of
#279.

This new component, `aws-s3-csi-controller`, will be the entry point for
our controller component. It's using
[controller-runtime](https://github.com/kubernetes-sigs/controller-runtime),
specifically, it implements
[`Reconciler`](https://pkg.go.dev/sigs.k8s.io/controller-runtime/pkg#hdr-Reconciler)
interface to reconcile Pods in the cluster. It schedules Mountpoint Pods
in turn to cluster events such as a new workload Pod using a PV backed
by S3 CSI Driver getting scheduled into the cluster. It'd then schedule
a Mountpoint Pod for that workload Pod in the same node to provide
volume for that Pod.

#279 is still
WIP and this component contains some TODOs and it's not in use anywhere
except in tests at the moment.

---

By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice.

---------

Signed-off-by: Burak Varlı <[email protected]>

.github/workflows/e2e-tests.yaml

@@ -135,6 +135,13 @@ jobs:
         run: |
           export ACTION=install_tools
           tests/e2e-kubernetes/scripts/run.sh
+      - name: Run Controller Tests
+        run: |
+          # envtest doesn't support all versions, here K8S_VERSION is a full version like 1.28.13,
+          # and in order to get latest supported version by envtest we convert it to 1.28.
+          export K8S_VERSION=${{ matrix.kubernetes-version }}
+          export ENVTEST_K8S_VERSION="${K8S_VERSION%.*}"
+          make e2e-controller
       - name: Create cluster
         run: |
           export ACTION=create_cluster

.gitignore

@@ -1,5 +1,6 @@
 **/credentials
 bin/
+tests/bin
 go.work
 go.work.sum
 .github/artifacts/benchmark-data.json

Makefile

@@ -52,6 +52,9 @@ E2E_REGION?=us-east-1
 E2E_COMMIT_ID?=local
 E2E_KUBECONFIG?=""
 
+# Kubernetes version to use in envtest for controller tests.
+ENVTEST_K8S_VERSION ?= 1.30.x
+
 # split words on hyphen, access by 1-index
 word-hyphen = $(word $2,$(subst -, ,$1))
 
@@ -143,8 +146,13 @@ cover:
 fmt:
 	go fmt ./...
 
+# Run controller tests with envtest.
+.PHONY: e2e-controller
+e2e-controller: envtest
+	KUBEBUILDER_ASSETS="$(shell $(ENVTEST) use $(ENVTEST_K8S_VERSION) --bin-dir $(TESTBIN) -p path)" go test ./tests/controller/... -ginkgo.v -test.v
+
 .PHONY: e2e
-e2e:
+e2e: e2e-controller
 	pushd tests/e2e-kubernetes; \
 	KUBECONFIG=${E2E_KUBECONFIG} go test -timeout 30m -ginkgo.vv --bucket-region=${E2E_REGION} --commit-id=${E2E_COMMIT_ID}; \
 	EXIT_CODE=$$?; \
@@ -158,3 +166,34 @@ check_style:
 .PHONY: clean
 clean:
 	rm -rf bin/ && docker system prune
+
+## Binaries used in tests.
+
+TESTBIN ?= $(shell pwd)/tests/bin
+$(TESTBIN):
+	mkdir -p $(TESTBIN)
+
+ENVTEST ?= $(TESTBIN)/setup-envtest
+ENVTEST_VERSION ?= release-0.19
+
+.PHONY: envtest
+envtest: $(ENVTEST)
+$(ENVTEST): $(TESTBIN)
+	$(call go-install-tool,$(ENVTEST),sigs.k8s.io/controller-runtime/tools/setup-envtest,$(ENVTEST_VERSION))
+
+# Copied from https://github.com/kubernetes-sigs/kubebuilder/blob/c32f9714456f7e5e7cc6c790bb87c7e5956e710b/pkg/plugins/golang/v4/scaffolds/internal/templates/makefile.go#L275-L289.
+# go-install-tool will 'go install' any package with custom target and name of binary, if it doesn't exist
+# $1 - target path with name of binary
+# $2 - package url which can be installed
+# $3 - specific version of package
+define go-install-tool
+@[ -f "$(1)-$(3)" ] || { \
+set -e; \
+package=$(2)@$(3) ;\
+echo "Downloading $${package}" ;\
+rm -f $(1) || true ;\
+GOBIN=$(TESTBIN) go install $${package} ;\
+mv $(1) $(1)-$(3) ;\
+} ;\
+ln -sf $(1)-$(3) $(1)
+endef

cmd/aws-s3-csi-controller/csicontroller/controller.go

@@ -0,0 +1,4 @@
+package csicontroller
+
+// Name of this component, this needs to be unique as its used as an identifier in logs and metrics.
+const Name = "aws-s3-csi-controller"