Introduce oc-cli for e2e tests

Most of e2e tests for CVO use `oc` cmds that are not trivial
to implement or import. See the introduced `oc/api/api.go`.

This pull introduces the implementation by spawning processes
to execute `oc` cmd.

The advantages are:

- We are ready to add more e2e tests that need `oc` cmds.
- We do not need to vendor any new pkgs into CVO, e.g.,
  `k8s.io/kubernetes/test/e2e/framework` which might give us
  headaches when bumping its version.
- The implementation can be easily replaced when needed in
  the future with a better one without oc-cli because the
  `test/oc/cli` pkg stays only in the `test/oc` pkg, and
  the tests in a pkg such as `/test/cvo` does not know
  the existence of `cli`.

Author: hongkailiu

.openshift-tests-extension/openshift_payload_cluster-version-operator.json

@@ -8,5 +8,15 @@
     "source": "openshift:payload:cluster-version-operator",
     "lifecycle": "blocking",
     "environmentSelector": {}
+  },
+  {
+    "name": "[Jira:\"Cluster Version Operator\"] cluster-version-operator-tests can use oc to get the client version",
+    "labels": {},
+    "resources": {
+      "isolation": {}
+    },
+    "source": "openshift:payload:cluster-version-operator",
+    "lifecycle": "blocking",
+    "environmentSelector": {}
   }
 ]

go.mod

@@ -5,6 +5,7 @@ go 1.24.0
 require (
 	github.com/blang/semver/v4 v4.0.0
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc
+	github.com/go-logr/logr v1.4.2
 	github.com/google/go-cmp v0.7.0
 	github.com/google/uuid v1.6.0
 	github.com/onsi/ginkgo/v2 v2.21.0
@@ -40,7 +41,6 @@ require (
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/emicklei/go-restful/v3 v3.12.2 // indirect
 	github.com/fxamacker/cbor/v2 v2.9.0 // indirect
-	github.com/go-logr/logr v1.4.2 // indirect
 	github.com/go-openapi/jsonpointer v0.21.0 // indirect
 	github.com/go-openapi/jsonreference v0.20.2 // indirect
 	github.com/go-openapi/swag v0.23.0 // indirect

test/cvo/cvo.go

@@ -3,10 +3,25 @@ package cvo
 import (
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
+
+	"github.com/openshift/cluster-version-operator/test/oc"
+	ocapi "github.com/openshift/cluster-version-operator/test/oc/api"
 )
 
+var logger = GinkgoLogr.WithName("cluster-version-operator-tests")
+
 var _ = Describe(`[Jira:"Cluster Version Operator"] cluster-version-operator-tests`, func() {
 	It("should support passing tests", func() {
 		Expect(true).To(BeTrue())
 	})
+
+	It("can use oc to get the client version", func() {
+		ocClient, err := oc.NewOC(logger)
+		Expect(err).NotTo(HaveOccurred())
+		Expect(ocClient).NotTo(BeNil())
+
+		output, err := ocClient.Version(ocapi.VersionOptions{Client: true})
+		Expect(err).NotTo(HaveOccurred())
+		Expect(output).To(ContainSubstring("Client Version:"))
+	})
 })

test/oc/api/api.go

@@ -0,0 +1,14 @@
+package api
+
+type ReleaseExtractOptions struct {
+	To string
+}
+
+type VersionOptions struct {
+	Client bool
+}
+
+type OC interface {
+	AdmReleaseExtract(o ReleaseExtractOptions) error
+	Version(o VersionOptions) (string, error)
+}

test/oc/cli/cli.go

@@ -0,0 +1,98 @@
+package cli
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os/exec"
+	"strings"
+	"time"
+
+	"github.com/go-logr/logr"
+
+	"github.com/openshift/cluster-version-operator/test/oc/api"
+)
+
+type client struct {
+	logger   logr.Logger
+	executor executor
+}
+
+type executor interface {
+	Run(args ...string) ([]byte, error)
+}
+
+type ocExecutor struct {
+	// logger is used to log oc commands
+	logger logr.Logger
+	// oc is the path to the oc binary
+	oc string
+	// execute executes a command
+	execute func(dir, command string, args ...string) ([]byte, error)
+}
+
+func (e *ocExecutor) Run(args ...string) ([]byte, error) {
+	logger := e.logger.WithValues("cmd", e.oc, "args", strings.Join(args, " "))
+	b, err := e.execute("", e.oc, args...)
+	if err != nil {
+		logger.Error(err, "Running command failed", "output", string(b))
+	} else {
+		logger.Info("Running command succeeded.")
+	}
+	return b, err
+}
+
+func newOCExecutor(oc string, timeout time.Duration, logger logr.Logger) (executor, error) {
+	return &ocExecutor{
+		logger: logger,
+		oc:     oc,
+		execute: func(dir, command string, args ...string) ([]byte, error) {
+			ctx, cancel := context.WithTimeout(context.Background(), timeout)
+			defer cancel()
+			c := exec.CommandContext(ctx, command, args...)
+			c.Dir = dir
+			o, err := c.CombinedOutput()
+			if errors.Is(ctx.Err(), context.DeadlineExceeded) {
+				return nil, fmt.Errorf("execution was terminated due to timeout")
+			}
+
+			return o, err
+		},
+	}, nil
+}
+
+// NewOCCli return a client for oc-cli.
+func NewOCCli(logger logr.Logger) (api.OC, error) {
+	oc, err := exec.LookPath("oc")
+	if err != nil {
+		return nil, err
+	}
+
+	executor, err := newOCExecutor(oc, 1*time.Second, logger)
+	if err != nil {
+		return nil, err
+	}
+	ret := client{
+		logger:   logger,
+		executor: executor,
+	}
+	return &ret, nil
+}
+
+func (c *client) AdmReleaseExtract(o api.ReleaseExtractOptions) error {
+	args := []string{"adm", "release", "extract", fmt.Sprintf("--to=%s", o.To)}
+	_, err := c.executor.Run(args...)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (c *client) Version(o api.VersionOptions) (string, error) {
+	args := []string{"version", fmt.Sprintf("--client=%t", o.Client)}
+	output, err := c.executor.Run(args...)
+	if err != nil {
+		return "", err
+	}
+	return string(output), nil
+}

test/oc/oc.go

@@ -0,0 +1,13 @@
+package oc
+
+import (
+	"github.com/go-logr/logr"
+
+	"github.com/openshift/cluster-version-operator/test/oc/api"
+	"github.com/openshift/cluster-version-operator/test/oc/cli"
+)
+
+// NewOC returns OC that provides utility functions used by the e2e tests
+func NewOC(logger logr.Logger) (api.OC, error) {
+	return cli.NewOCCli(logger)
+}