Merge pull request etcd-io#12274 from ptabor/20200907-fix-cov-e2e-tests

tests/e2e,etcdctl,etcdmain: Fix go test --tags cov -v ./tests/e2e

etcdctl/ctlv2/ctl.go

@@ -26,7 +26,7 @@ import (
 	"github.com/urfave/cli"
 )
 
-func Start() {
+func Start() error {
 	app := cli.NewApp()
 	app.Name = "etcdctl"
 	app.Version = version.Version
@@ -72,8 +72,11 @@ func Start() {
 		command.NewRoleCommands(),
 		command.NewAuthCommands(),
 	}
+	return app.Run(os.Args)
+}
 
-	err := runCtlV2(app)
+func MustStart() {
+	err := Start()
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)

etcdctl/ctlv3/ctl.go

@@ -95,6 +95,19 @@ func init() {
 	)
 }
 
+func Start() error {
+	rootCmd.SetUsageFunc(usageFunc)
+	// Make help just show the usage
+	rootCmd.SetHelpTemplate(`{{.UsageString}}`)
+	return rootCmd.Execute()
+}
+
+func MustStart() {
+	if err := Start(); err != nil {
+		command.ExitWithError(command.ExitError, err)
+	}
+}
+
 func init() {
 	cobra.EnablePrefixMatching = true
 }

etcdctl/main.go

@@ -27,20 +27,44 @@ const (
 	apiEnv = "ETCDCTL_API"
 )
 
+/**
+mainWithError is fully analogous to main, but instead of signaling errors
+by os.Exit, it exposes the error explicitly, such that test-logic can intercept
+control to e.g. dump coverage data (even for test-for-failure scenarios).
+*/
+func mainWithError() error {
+	apiv := os.Getenv(apiEnv)
+
+	// unset apiEnv to avoid side-effect for future env and flag parsing.
+	os.Unsetenv(apiEnv)
+
+	if len(apiv) == 0 || apiv == "3" {
+		return ctlv3.Start()
+	}
+
+	if apiv == "2" {
+		return ctlv2.Start()
+	}
+
+	fmt.Fprintf(os.Stderr, "unsupported API version: %s\n", apiv)
+	return fmt.Errorf("unsupported API version: %s", apiv)
+}
+
 func main() {
 	apiv := os.Getenv(apiEnv)
+
 	// unset apiEnv to avoid side-effect for future env and flag parsing.
 	os.Unsetenv(apiEnv)
 	if len(apiv) == 0 || apiv == "3" {
-		ctlv3.Start()
+		ctlv3.MustStart()
 		return
 	}
 
 	if apiv == "2" {
-		ctlv2.Start()
+		ctlv2.MustStart()
 		return
 	}
 
-	fmt.Fprintln(os.Stderr, "unsupported API version", apiv)
+	fmt.Fprintf(os.Stderr, "unsupported API version: %v\n", apiv)
 	os.Exit(1)
 }

etcdctl/main_test.go

@@ -15,15 +15,52 @@
 package main
 
 import (
+	"log"
 	"os"
 	"strings"
 	"testing"
 )
 
-func TestMain(t *testing.T) {
+func SplitTestArgs(args []string) (testArgs, appArgs []string) {
+	for i, arg := range os.Args {
+		switch {
+		case strings.HasPrefix(arg, "-test."):
+			testArgs = append(testArgs, arg)
+		case i == 0:
+			appArgs = append(appArgs, arg)
+			testArgs = append(testArgs, arg)
+		default:
+			appArgs = append(appArgs, arg)
+		}
+	}
+	return
+}
+
+// Empty test to avoid no-tests warning.
+func TestEmpty(t *testing.T) {}
+
+/**
+ * The purpose of this "test" is to run etcdctl with code-coverage
+ * collection turned on. The technique is documented here:
+ *
+ * https://www.cyphar.com/blog/post/20170412-golang-integration-coverage
+ */
+func TestMain(m *testing.M) {
 	// don't launch etcdctl when invoked via go test
 	if strings.HasSuffix(os.Args[0], "etcdctl.test") {
 		return
 	}
-	main()
+
+	testArgs, appArgs := SplitTestArgs(os.Args)
+
+	os.Args = appArgs
+
+	err := mainWithError()
+	if err != nil {
+		log.Fatalf("etcdctl failed with: %v", err)
+	}
+
+	// This will generate coverage files:
+	os.Args = testArgs
+	m.Run()
 }

etcdmain/etcd.go

@@ -49,13 +49,13 @@ var (
 	dirEmpty  = dirType("empty")
 )
 
-func startEtcdOrProxyV2() {
+func startEtcdOrProxyV2(args []string) {
 	grpc.EnableTracing = false
 
 	cfg := newConfig()
 	defaultInitialCluster := cfg.ec.InitialCluster
 
-	err := cfg.parse(os.Args[1:])
+	err := cfg.parse(args[1:])
 	lg := cfg.ec.GetLogger()
 	if lg == nil {
 		var zapError error
@@ -66,6 +66,7 @@ func startEtcdOrProxyV2() {
 			os.Exit(1)
 		}
 	}
+	lg.Info("Running: ", zap.Strings("args", args))
 	if err != nil {
 		lg.Warn("failed to verify flags", zap.Error(err))
 		switch err {

etcdmain/gateway.go

@@ -99,6 +99,9 @@ func startGateway(cmd *cobra.Command, args []string) {
 		os.Exit(1)
 	}
 
+	// We use os.Args to show all the arguments (not only passed-through Cobra).
+	lg.Info("Running: ", zap.Strings("args", os.Args))
+
 	srvs := discoverEndpoints(lg, gatewayDNSCluster, gatewayCA, gatewayInsecureDiscovery, gatewayDNSClusterServiceName)
 	if len(srvs.Endpoints) == 0 {
 		// no endpoints discovered, fall back to provided endpoints

etcdmain/main.go

@@ -17,22 +17,16 @@ package etcdmain
 import (
 	"fmt"
 	"os"
-	"strings"
 
 	"github.com/coreos/go-systemd/v22/daemon"
 	"go.uber.org/zap"
 )
 
-func Main() {
+func Main(args []string) {
 	checkSupportArch()
 
-	if len(os.Args) > 1 {
-		cmd := os.Args[1]
-		if covArgs := os.Getenv("ETCDCOV_ARGS"); len(covArgs) > 0 {
-			args := strings.Split(os.Getenv("ETCDCOV_ARGS"), "\xe7\xcd")[1:]
-			rootCmd.SetArgs(args)
-			cmd = "grpc-proxy"
-		}
+	if len(args) > 1 {
+		cmd := args[1]
 		switch cmd {
 		case "gateway", "grpc-proxy":
 			if err := rootCmd.Execute(); err != nil {
@@ -43,7 +37,7 @@ func Main() {
 		}
 	}
 
-	startEtcdOrProxyV2()
+	startEtcdOrProxyV2(args)
 }
 
 func notifySystemd(lg *zap.Logger) {

main.go

@@ -22,8 +22,12 @@
 //
 package main
 
-import "go.etcd.io/etcd/v3/etcdmain"
+import (
+	"os"
+
+	"go.etcd.io/etcd/v3/etcdmain"
+)
 
 func main() {
-	etcdmain.Main()
+	etcdmain.Main(os.Args)
 }