Fix grpc example (#3549)

* Fix linter issues

* Use Printf for log with no KV argument

* Fix non-deterministic test

Author: raphael

codegen/service/templates/endpoint.go.tpl

@@ -24,6 +24,6 @@ func (s *{{ .ServiceVarName }}srvc) {{ .VarName }}(ctx context.Context{{ if .Pay
 		{{- end }}
 	{{- end }}
 {{- end }}
-	log.Print(ctx, "{{ .ServiceVarName }}.{{ .Name }}")
+	log.Printf(ctx, "{{ .ServiceVarName }}.{{ .Name }}")
 	return
 }

grpc/codegen/client-no-server-pkgpath.golden

@@ -8,8 +8,8 @@ import (
 	"google.golang.org/grpc/credentials/insecure"
 )
 
-func doGRPC(scheme, host string, timeout int, debug bool) (goa.Endpoint, any, error) {
-	conn, err := grpc.Dial(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
+func doGRPC(_, host string, _ int, _ bool) (goa.Endpoint, any, error) {
+	conn, err := grpc.NewClient(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "could not connect to gRPC server at %s: %v\n", host, err)
 	}

grpc/codegen/client-no-server.golden

@@ -8,8 +8,8 @@ import (
 	"google.golang.org/grpc/credentials/insecure"
 )
 
-func doGRPC(scheme, host string, timeout int, debug bool) (goa.Endpoint, any, error) {
-	conn, err := grpc.Dial(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
+func doGRPC(_, host string, _ int, _ bool) (goa.Endpoint, any, error) {
+	conn, err := grpc.NewClient(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "could not connect to gRPC server at %s: %v\n", host, err)
 	}

grpc/codegen/client-server-hosting-multiple-services-pkgpath.golden

@@ -8,8 +8,8 @@ import (
 	"google.golang.org/grpc/credentials/insecure"
 )
 
-func doGRPC(scheme, host string, timeout int, debug bool) (goa.Endpoint, any, error) {
-	conn, err := grpc.Dial(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
+func doGRPC(_, host string, _ int, _ bool) (goa.Endpoint, any, error) {
+	conn, err := grpc.NewClient(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "could not connect to gRPC server at %s: %v\n", host, err)
 	}

grpc/codegen/client-server-hosting-multiple-services.golden

@@ -8,8 +8,8 @@ import (
 	"google.golang.org/grpc/credentials/insecure"
 )
 
-func doGRPC(scheme, host string, timeout int, debug bool) (goa.Endpoint, any, error) {
-	conn, err := grpc.Dial(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
+func doGRPC(_, host string, _ int, _ bool) (goa.Endpoint, any, error) {
+	conn, err := grpc.NewClient(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "could not connect to gRPC server at %s: %v\n", host, err)
 	}

grpc/codegen/client-server-hosting-service-subset-pkgpath.golden

@@ -8,8 +8,8 @@ import (
 	"google.golang.org/grpc/credentials/insecure"
 )
 
-func doGRPC(scheme, host string, timeout int, debug bool) (goa.Endpoint, any, error) {
-	conn, err := grpc.Dial(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
+func doGRPC(_, host string, _ int, _ bool) (goa.Endpoint, any, error) {
+	conn, err := grpc.NewClient(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "could not connect to gRPC server at %s: %v\n", host, err)
 	}

grpc/codegen/client-server-hosting-service-subset.golden

@@ -8,8 +8,8 @@ import (
 	"google.golang.org/grpc/credentials/insecure"
 )
 
-func doGRPC(scheme, host string, timeout int, debug bool) (goa.Endpoint, any, error) {
-	conn, err := grpc.Dial(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
+func doGRPC(_, host string, _ int, _ bool) (goa.Endpoint, any, error) {
+	conn, err := grpc.NewClient(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "could not connect to gRPC server at %s: %v\n", host, err)
 	}

grpc/codegen/templates/do_grpc_cli.go.tpl

@@ -1,5 +1,5 @@
-func doGRPC(scheme, host string, timeout int, debug bool) (goa.Endpoint, any, error) {
-	conn, err := grpc.Dial(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
+func doGRPC(_, host string, _ int, _ bool) (goa.Endpoint, any, error) {
+	conn, err := grpc.NewClient(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
 	if err != nil {
     fmt.Fprintf(os.Stderr, "could not connect to gRPC server at %s: %v\n", host, err)
   }

grpc/middleware/canceler_test.go

@@ -4,8 +4,10 @@ import (
 	"context"
 	"testing"
 
-	grpcm "goa.design/goa/v3/grpc/middleware"
+	"github.com/stretchr/testify/assert"
 	"google.golang.org/grpc"
+
+	grpcm "goa.design/goa/v3/grpc/middleware"
 )
 
 type (
@@ -46,15 +48,11 @@ func TestStreamCanceler(t *testing.T) {
 	for _, c := range cases {
 		t.Run(c.name, func(t *testing.T) {
 			ctx, cancel := context.WithCancel(context.Background())
-
-			go func() {
-				cancel()
-			}()
-
-			if err := grpcm.StreamCanceler(ctx)(nil, c.stream, stream, c.handler); err != nil {
-				if err.Error() != "server is stopping" {
-					t.Errorf("StreamCanceler error: %v", err)
-				}
+			interceptor := grpcm.StreamCanceler(ctx)
+			cancel()
+			err := interceptor(nil, c.stream, stream, c.handler)
+			if err != nil {
+				assert.ErrorContains(t, err, "server is stopping")
 			}
 		})
 	}