chore: refactor and add test

Author: ericzzzzzzz

pkg/skaffold/gcp/auth.go

@@ -71,6 +71,7 @@ type tokenSource struct {
 }
 
 func (ts tokenSource) Token() (*oauth2.Token, error) {
+	// the command return a json object containing id_token, access_token, token_expiry
 	cmd := exec.Command("gcloud", "auth", "print-identity-token", "--format=json")
 	var body bytes.Buffer
 	cmd.Stdout = &body
@@ -85,20 +86,27 @@ func (ts tokenSource) Token() (*oauth2.Token, error) {
 	return &oauth2.Token{AccessToken: t.AccessToken, Expiry: t.TokenExpiry}, nil
 }
 
-func activeUserCredentials(ctx context.Context) (*google.Credentials, error) {
+func activeUserCredentialsOnce() (*google.Credentials, error) {
 	credsOnce.Do(func() {
-		var ts tokenSource
-		t, err := ts.Token()
+		c, err := activeUserCredentials()
 		if err != nil {
 			log.Entry(context.TODO()).Infof("unable to retrieve gcloud access token: %v", err)
 			log.Entry(context.TODO()).Info("falling back to application default credentials")
 			credsErr = fmt.Errorf("retrieving gcloud access token: %w", err)
 			return
 		}
-
-		c := &google.Credentials{TokenSource: oauth2.ReuseTokenSource(t, ts)}
 		creds = c
 	})
 
 	return creds, credsErr
 }
+
+func activeUserCredentials() (*google.Credentials, error) {
+	var ts tokenSource
+	t, err := ts.Token()
+	if err != nil {
+		return nil, err
+	}
+	c := &google.Credentials{TokenSource: oauth2.ReuseTokenSource(t, ts)}
+	return c, nil
+}

pkg/skaffold/gcp/auth_test.go

@@ -20,12 +20,12 @@ limitations under the License.
 package gcp
 
 import (
-	"context"
 	"fmt"
 	"testing"
 
 	"github.com/docker/cli/cli/config/configfile"
 
+	"github.com/GoogleContainerTools/skaffold/v2/pkg/skaffold/util"
 	"github.com/GoogleContainerTools/skaffold/v2/testutil"
 )
 
@@ -114,11 +114,45 @@ func TestAutoConfigureGCRCredentialHelper(t *testing.T) {
 	}
 }
 
-func TestTesting(t *testing.T) {
-	credentials, err := activeUserCredentials(context.TODO())
-	if err != nil {
-		fmt.Println(err)
-		fmt.Println("err")
+func TestActiveUserCredentials(t *testing.T) {
+	output := `{
+		"access_token": "access_token_value",
+		"id_token": "id_token_value",
+		"token_expiry": "2023-03-23T23:10:40Z"
+	}`
+
+	tests := []struct {
+		name        string
+		mockCommand util.Command
+		shouldErr   bool
+		expected    string
+	}{
+		{
+			name: "get credential succeed",
+			mockCommand: testutil.CmdRunWithOutput("gcloud auth print-identity-token --format=json", output).
+				AndRunWithOutput("gcloud auth print-identity-token --format=json", output),
+			expected: "access_token_value",
+		},
+		{
+			name:        "command error, get error",
+			mockCommand: testutil.CmdRunErr("gcloud auth print-identity-token --format=json", fmt.Errorf("command exited with non-zero code")),
+			shouldErr:   true,
+		},
+		{
+			name:        "invalid json, get error",
+			mockCommand: testutil.CmdRunWithOutput("gcloud auth print-identity-token --format=json", "{{{"),
+			shouldErr:   true,
+		},
+	}
+	for _, test := range tests {
+		testutil.Run(t, test.name, func(t *testutil.T) {
+			t.Override(&util.DefaultExecCommand, test.mockCommand)
+			out, err := activeUserCredentials()
+			t.CheckError(test.shouldErr, err)
+			if err == nil {
+				token, _ := out.TokenSource.Token()
+				t.CheckDeepEqual(test.expected, token.AccessToken)
+			}
+		})
 	}
-	fmt.Println(credentials.TokenSource.Token())
 }

pkg/skaffold/gcp/client.go

@@ -31,7 +31,7 @@ func ClientOptions(ctx context.Context) []option.ClientOption {
 		option.WithUserAgent(version.UserAgent()),
 	}
 
-	creds, cErr := activeUserCredentials(ctx)
+	creds, cErr := activeUserCredentialsOnce()
 	if cErr == nil && creds != nil {
 		options = append(options, option.WithCredentials(creds))
 	}