Add a library.PinnipedCLIPath() test helper, with caching.

Caching saves us a little bit of time now that we're using the CLI in more and more tests.

Signed-off-by: Matt Moyer <moyerm@vmware.com>

test/integration/cli_test.go

@@ -42,7 +42,7 @@ func TestCLIGetKubeconfigStaticToken(t *testing.T) {
 	authenticator := library.CreateTestWebhookAuthenticator(ctx, t)
 
 	// Build pinniped CLI.
-	pinnipedExe := buildPinnipedCLI(t)
+	pinnipedExe := library.PinnipedCLIPath(t)
 
 	for _, tt := range []struct {
 		name         string
@@ -109,25 +109,6 @@ func TestCLIGetKubeconfigStaticToken(t *testing.T) {
 	}
 }
 
-func buildPinnipedCLI(t *testing.T) string {
-	t.Helper()
-
-	pinnipedExeDir, err := ioutil.TempDir("", "pinniped-cli-test-*")
-	require.NoError(t, err)
-	t.Cleanup(func() { require.NoError(t, os.RemoveAll(pinnipedExeDir)) })
-
-	pinnipedExe := filepath.Join(pinnipedExeDir, "pinniped")
-	output, err := exec.Command(
-		"go",
-		"build",
-		"-o",
-		pinnipedExe,
-		"go.pinniped.dev/cmd/pinniped",
-	).CombinedOutput()
-	require.NoError(t, err, string(output))
-	return pinnipedExe
-}
-
 func runPinnipedCLI(t *testing.T, pinnipedExe string, args ...string) (string, string) {
 	t.Helper()
 	var stdout, stderr bytes.Buffer
@@ -145,8 +126,7 @@ func TestCLILoginOIDC(t *testing.T) {
 	defer cancel()
 
 	// Build pinniped CLI.
-	t.Logf("building CLI binary")
-	pinnipedExe := buildPinnipedCLI(t)
+	pinnipedExe := library.PinnipedCLIPath(t)
 
 	// Run "pinniped login oidc" to get an ExecCredential struct with an OIDC ID token.
 	credOutput, sessionCachePath := runPinniedLoginOIDC(ctx, t, pinnipedExe)

test/integration/concierge_credentialrequest_test.go

@@ -65,7 +65,7 @@ func TestSuccessfulCredentialRequest(t *testing.T) {
 				return library.CreateTestJWTAuthenticator(ctx, t)
 			},
 			token: func(t *testing.T) (string, string, []string) {
-				pinnipedExe := buildPinnipedCLI(t)
+				pinnipedExe := library.PinnipedCLIPath(t)
 				credOutput, _ := runPinniedLoginOIDC(ctx, t, pinnipedExe)
 				token := credOutput.Status.Token
 

test/library/cli.go

@@ -0,0 +1,45 @@
+// Copyright 2020 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package library
+
+import (
+	"io/ioutil"
+	"os/exec"
+	"path/filepath"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"go.pinniped.dev/internal/testutil"
+)
+
+//nolint: gochecknoglobals
+var pinnipedCLIBinaryCache struct {
+	buf   []byte
+	mutex sync.Mutex
+}
+
+// PinnipedCLIPath returns the path to the Pinniped CLI binary, built on demand and cached between tests.
+func PinnipedCLIPath(t *testing.T) string {
+	t.Helper()
+	pinnipedCLIBinaryCache.mutex.Lock()
+	defer pinnipedCLIBinaryCache.mutex.Unlock()
+	path := filepath.Join(testutil.TempDir(t), "pinniped")
+	if pinnipedCLIBinaryCache.buf != nil {
+		t.Log("using previously built pinniped CLI binary")
+		require.NoError(t, ioutil.WriteFile(path, pinnipedCLIBinaryCache.buf, 0500))
+		return path
+	}
+
+	t.Log("building pinniped CLI binary")
+	output, err := exec.Command("go", "build", "-o", path, "go.pinniped.dev/cmd/pinniped").CombinedOutput()
+	require.NoError(t, err, string(output))
+
+	// Fill our cache so we don't have to do this again.
+	pinnipedCLIBinaryCache.buf, err = ioutil.ReadFile(path)
+	require.NoError(t, err, string(output))
+
+	return path
+}