Prefer go_grpc_library

This allows for easier compiler upgrades via rules_go upgrades

Author: mering

language/go/config.go

@@ -147,8 +147,8 @@ const (
 )
 
 var (
-	defaultGoProtoCompilers = []string{"@io_bazel_rules_go//proto:go_proto"}
-	defaultGoGrpcCompilers  = []string{"@io_bazel_rules_go//proto:go_grpc"}
+	defaultGoProtoCompilers = []string{}
+	defaultGoGrpcCompilers  = []string{}
 )
 
 func (m testMode) String() string {

language/go/constants.go

@@ -31,9 +31,9 @@ const (
 	// mode for libraries that contained .pb.go files and .proto files.
 	legacyProtoFilegroupName = "go_default_library_protos"
 
-	// grpcCompilerLabel is the label for the gRPC compiler plugin, used in the
-	// "compilers" attribute of go_proto_library rules.
-	grpcCompilerLabel = "@io_bazel_rules_go//proto:go_grpc"
+	// oldGrpcCompilerLabel is the label for the old gRPC compiler plugin, used
+	// in the "compilers" attribute of go_proto_library rules.
+	oldGrpcCompilerLabel = "@io_bazel_rules_go//proto:go_grpc"
 
 	// goProtoSuffix is the suffix applied to the labels of all generated
 	// go_proto_library targets.

language/go/fix.go

@@ -171,15 +171,15 @@ func migrateLibraryEmbed(c *config.Config, f *rule.File) {
 	}
 }
 
-// migrateGrpcCompilers converts "go_grpc_library" rules into "go_proto_library"
-// rules with a "compilers" attribute.
+// migrateGrpcCompilers converts "go_proto_library" rules with a "compilers"
+// attribute containing exactly oldGrpcCompilerLabel into "go_grpc_library" rules.
 func migrateGrpcCompilers(c *config.Config, f *rule.File) {
 	for _, r := range f.Rules {
-		if r.Kind() != "go_grpc_library" || r.ShouldKeep() || r.Attr("compilers") != nil {
+		if r.Kind() != "go_proto_library" || r.ShouldKeep() || r.Attr("compilers") == nil || len(r.AttrStrings("compilers")) != 1 || strListAttrContains(r, "compilers", oldGrpcCompilerLabel) {
 			continue
 		}
-		r.SetKind("go_proto_library")
-		r.SetAttr("compilers", []string{grpcCompilerLabel})
+		r.SetKind("go_grpc_library")
+		r.SetAttr("compilers", []string{})
 	}
 }
 

language/go/generate.go

@@ -454,14 +454,19 @@ func (g *generator) generateProto(mode proto.Mode, target protoTarget, importPat
 		}
 	}
 
-	goProtoLibrary := rule.NewRule("go_proto_library", goProtoName)
+	var goProtoLibrary *rule.Rule
+	if target.hasServices && !gc.goGrpcCompilersSet {
+		goProtoLibrary = rule.NewRule("go_grpc_library", goProtoName)
+	} else {
+		goProtoLibrary = rule.NewRule("go_proto_library", goProtoName)
+		if gc.goProtoCompilersSet {
+			goProtoLibrary.SetAttr("compilers", gc.goProtoCompilers)
+		} else if gc.goGrpcCompilersSet {
+			goProtoLibrary.SetAttr("compilers", gc.goGrpcCompilers)
+		}
+	}
 	goProtoLibrary.SetAttr("proto", ":"+protoName)
 	g.setImportAttrs(goProtoLibrary, importPath)
-	if target.hasServices {
-		goProtoLibrary.SetAttr("compilers", gc.goGrpcCompilers)
-	} else if gc.goProtoCompilersSet {
-		goProtoLibrary.SetAttr("compilers", gc.goProtoCompilers)
-	}
 	if g.shouldSetVisibility {
 		goProtoLibrary.SetAttr("visibility", visibility)
 	}