Add java_generate_proto directive (#181)

Addresses part 1 of #180

java/gazelle/configure.go

@@ -56,6 +56,7 @@ func (jc *Configurer) KnownDirectives() []string {
 		javaconfig.JavaModuleGranularityDirective,
 		javaconfig.JavaTestFileSuffixes,
 		javaconfig.JavaTestMode,
+		javaconfig.JavaGenerateProto,
 	}
 }
 
@@ -107,6 +108,17 @@ func (jc *Configurer) Configure(c *config.Config, rel string, f *rule.File) {
 
 			case javaconfig.JavaTestMode:
 				cfg.SetTestMode(d.Value)
+
+			case javaconfig.JavaGenerateProto:
+				switch d.Value {
+				case "true":
+					cfg.SetGenerateProto(true)
+				case "false":
+					cfg.SetGenerateProto(false)
+				default:
+					jc.lang.logger.Fatal().Msgf("invalid value for directive %q: %s: possible values are true/false",
+						javaconfig.JavaGenerateProto, d.Value)
+				}
 			}
 		}
 	}

java/gazelle/generate.go

@@ -50,58 +50,10 @@ func (l javaLang) GenerateRules(args language.GenerateArgs) language.GenerateRes
 		return res
 	}
 
-	var protoRuleNames []string
-	protoPackages := make(map[string]proto.Package)
-	protoFileInfo := make(map[string]proto.FileInfo)
-	for _, r := range args.OtherGen {
-		if r.Kind() != "proto_library" {
-			continue
-		}
-		pkg := r.PrivateAttr(proto.PackageKey).(proto.Package)
-		protoPackages[r.Name()] = pkg
-		for name, info := range pkg.Files {
-			protoFileInfo[name] = info
-		}
-		protoRuleNames = append(protoRuleNames, r.Name())
-	}
-	sort.Strings(protoRuleNames)
-
 	isModule := cfg.ModuleGranularity() == "module"
 
-	for _, protoRuleName := range protoRuleNames {
-		protoPackage := protoPackages[protoRuleName]
-
-		jplName := strings.TrimSuffix(protoRuleName, "_proto") + "_java_proto"
-		jglName := strings.TrimSuffix(protoRuleName, "_proto") + "_java_grpc"
-		jlName := strings.TrimSuffix(protoRuleName, "_proto") + "_java_library"
-
-		rjpl := rule.NewRule("java_proto_library", jplName)
-		rjpl.SetAttr("deps", []string{":" + protoRuleName})
-		res.Gen = append(res.Gen, rjpl)
-		res.Imports = append(res.Imports, types.ResolveInput{})
-
-		if protoPackage.HasServices {
-			r := rule.NewRule("java_grpc_library", jglName)
-			r.SetAttr("srcs", []string{":" + protoRuleName})
-			r.SetAttr("deps", []string{":" + jplName})
-			res.Gen = append(res.Gen, r)
-			res.Imports = append(res.Imports, types.ResolveInput{})
-		}
-
-		rjl := rule.NewRule("java_library", jlName)
-		rjl.SetAttr("visibility", []string{"//:__subpackages__"})
-		var exports []string
-		if protoPackage.HasServices {
-			exports = append(exports, ":"+jglName)
-		}
-		rjl.SetAttr("exports", append(exports, ":"+jplName))
-		packageName := types.NewPackageName(protoPackage.Options["java_package"])
-		log.Debug().Str("pkg", packageName.Name).Msg("adding the proto import statement")
-		rjl.SetPrivateAttr(packagesKey, []types.ResolvableJavaPackage{*types.NewResolvableJavaPackage(packageName, false, false)})
-		res.Gen = append(res.Gen, rjl)
-		res.Imports = append(res.Imports, types.ResolveInput{
-			PackageNames: sorted_set.NewSortedSetFn([]types.PackageName{packageName}, types.PackageNameLess),
-		})
+	if cfg.GenerateProto() {
+		generateProtoLibraries(args, log, &res)
 	}
 
 	javaFilenamesRelativeToPackage := filterStrSlice(args.RegularFiles, func(f string) bool { return filepath.Ext(f) == ".java" })
@@ -351,6 +303,60 @@ func (l javaLang) collectRuntimeDeps(kind, name string, file *rule.File) *sorted
 	return runtimeDeps
 }
 
+func generateProtoLibraries(args language.GenerateArgs, log zerolog.Logger, res *language.GenerateResult) {
+	var protoRuleNames []string
+	protoPackages := make(map[string]proto.Package)
+	protoFileInfo := make(map[string]proto.FileInfo)
+	for _, r := range args.OtherGen {
+		if r.Kind() != "proto_library" {
+			continue
+		}
+		pkg := r.PrivateAttr(proto.PackageKey).(proto.Package)
+		protoPackages[r.Name()] = pkg
+		for name, info := range pkg.Files {
+			protoFileInfo[name] = info
+		}
+		protoRuleNames = append(protoRuleNames, r.Name())
+	}
+	sort.Strings(protoRuleNames)
+
+	for _, protoRuleName := range protoRuleNames {
+		protoPackage := protoPackages[protoRuleName]
+
+		jplName := strings.TrimSuffix(protoRuleName, "_proto") + "_java_proto"
+		jglName := strings.TrimSuffix(protoRuleName, "_proto") + "_java_grpc"
+		jlName := strings.TrimSuffix(protoRuleName, "_proto") + "_java_library"
+
+		rjpl := rule.NewRule("java_proto_library", jplName)
+		rjpl.SetAttr("deps", []string{":" + protoRuleName})
+		res.Gen = append(res.Gen, rjpl)
+		res.Imports = append(res.Imports, types.ResolveInput{})
+
+		if protoPackage.HasServices {
+			r := rule.NewRule("java_grpc_library", jglName)
+			r.SetAttr("srcs", []string{":" + protoRuleName})
+			r.SetAttr("deps", []string{":" + jplName})
+			res.Gen = append(res.Gen, r)
+			res.Imports = append(res.Imports, types.ResolveInput{})
+		}
+
+		rjl := rule.NewRule("java_library", jlName)
+		rjl.SetAttr("visibility", []string{"//:__subpackages__"})
+		var exports []string
+		if protoPackage.HasServices {
+			exports = append(exports, ":"+jglName)
+		}
+		rjl.SetAttr("exports", append(exports, ":"+jplName))
+		packageName := types.NewPackageName(protoPackage.Options["java_package"])
+		log.Debug().Str("pkg", packageName.Name).Msg("adding the proto import statement")
+		rjl.SetPrivateAttr(packagesKey, []types.ResolvableJavaPackage{*types.NewResolvableJavaPackage(packageName, false, false)})
+		res.Gen = append(res.Gen, rjl)
+		res.Imports = append(res.Imports, types.ResolveInput{
+			PackageNames: sorted_set.NewSortedSetFn([]types.PackageName{packageName}, types.PackageNameLess),
+		})
+	}
+}
+
 // We exclude intra-target imports because otherwise we'd get self-dependencies come resolve time.
 // toExports is optional and may be nil. All other parameters are required and must be non-nil.
 func addNonLocalImportsAndExports(toImports *sorted_set.SortedSet[types.PackageName], toExports *sorted_set.SortedSet[types.PackageName], fromImportedClasses *sorted_set.SortedSet[types.ClassName], fromPackages *sorted_set.SortedSet[types.PackageName], fromExportedClasses *sorted_set.SortedSet[types.ClassName], pkg types.PackageName, localClasses *sorted_set.SortedSet[string]) {

java/gazelle/javaconfig/config.go

@@ -37,6 +37,11 @@ const (
 
 	// JavaTestMode allows user to choose from per file test or per directory test suite.
 	JavaTestMode = "java_test_mode"
+
+	// JavaGenerateProto tells the code generator whether to generate `java_proto_library` (and `java_library`)
+	// rules when a `proto_library` rule is present.
+	// Can be either "true" or "false". Defaults to "true".
+	JavaGenerateProto = "java_generate_proto"
 )
 
 // Configs is an extension of map[string]*Config. It provides finding methods
@@ -50,6 +55,7 @@ func (c *Config) NewChild() *Config {
 		parent:                 c,
 		extensionEnabled:       c.extensionEnabled,
 		isModuleRoot:           false,
+		generateProto:          true,
 		mavenInstallFile:       c.mavenInstallFile,
 		moduleGranularity:      c.moduleGranularity,
 		repoRoot:               c.repoRoot,
@@ -75,6 +81,7 @@ type Config struct {
 
 	extensionEnabled       bool
 	isModuleRoot           bool
+	generateProto          bool
 	mavenInstallFile       string
 	moduleGranularity      string
 	repoRoot               string
@@ -94,6 +101,7 @@ func New(repoRoot string) *Config {
 	return &Config{
 		extensionEnabled:       true,
 		isModuleRoot:           false,
+		generateProto:          true,
 		mavenInstallFile:       "maven_install.json",
 		moduleGranularity:      "package",
 		repoRoot:               repoRoot,
@@ -118,6 +126,14 @@ func (c Config) IsModuleRoot() bool {
 	return c.isModuleRoot
 }
 
+func (c *Config) GenerateProto() bool {
+	return c.generateProto
+}
+
+func (c *Config) SetGenerateProto(generate bool) {
+	c.generateProto = generate
+}
+
 func (c Config) MavenInstallFile() string {
 	return filepath.Join(c.repoRoot, c.mavenInstallFile)
 }

java/gazelle/testdata/proto/generate_false/src/main/proto/example/hello/BUILD.in

@@ -0,0 +1 @@
+# gazelle:java_generate_proto false

java/gazelle/testdata/proto/generate_false/src/main/proto/example/hello/BUILD.out

@@ -0,0 +1,13 @@
+load("@rules_proto//proto:defs.bzl", "proto_library")
+
+# gazelle:java_generate_proto false
+
+proto_library(
+    name = "example_hello_proto",
+    srcs = [
+        "book.proto",
+        "hello.proto",
+    ],
+    visibility = ["//visibility:public"],
+    deps = ["//example/hello:hello_proto"],
+)

java/gazelle/testdata/proto/generate_false/src/main/proto/example/hello/book.proto

@@ -0,0 +1,12 @@
+syntax = "proto3";
+
+package example.hello;
+
+option java_outer_classname = "HelloProto";
+option java_multiple_files = true;
+option java_package = "com.example.hello";
+
+message Book {
+  string title = 1;
+  string author = 2;
+}

java/gazelle/testdata/proto/generate_false/src/main/proto/example/hello/hello.proto

@@ -0,0 +1,16 @@
+syntax = "proto3";
+
+package example.hello;
+
+import "example/hello/book.proto";
+
+option java_outer_classname = "HelloProto";
+option java_multiple_files = true;
+option java_package = "com.example.hello";
+
+message BarRequest {
+  string name = 1;
+  Book book = 2;
+}
+
+message BarResponse { string message = 1; }

java/gazelle/testdata/proto/generate_true/src/main/proto/example/hello/BUILD.in

@@ -0,0 +1 @@
+# gazelle:java_generate_proto true

java/gazelle/testdata/proto/generate_true/src/main/proto/example/hello/BUILD.out

@@ -0,0 +1,25 @@
+load("@rules_proto//proto:defs.bzl", "proto_library")
+load("@rules_java//java:defs.bzl", "java_library", "java_proto_library")
+
+# gazelle:java_generate_proto true
+
+proto_library(
+    name = "example_hello_proto",
+    srcs = [
+        "book.proto",
+        "hello.proto",
+    ],
+    visibility = ["//visibility:public"],
+    deps = ["//example/hello:hello_proto"],
+)
+
+java_proto_library(
+    name = "example_hello_java_proto",
+    deps = [":example_hello_proto"],
+)
+
+java_library(
+    name = "example_hello_java_library",
+    visibility = ["//:__subpackages__"],
+    exports = [":example_hello_java_proto"],
+)

java/gazelle/testdata/proto/generate_true/src/main/proto/example/hello/book.proto

@@ -0,0 +1,12 @@
+syntax = "proto3";
+
+package example.hello;
+
+option java_outer_classname = "HelloProto";
+option java_multiple_files = true;
+option java_package = "com.example.hello";
+
+message Book {
+  string title = 1;
+  string author = 2;
+}

java/gazelle/testdata/proto/generate_true/src/main/proto/example/hello/hello.proto

@@ -0,0 +1,16 @@
+syntax = "proto3";
+
+package example.hello;
+
+import "example/hello/book.proto";
+
+option java_outer_classname = "HelloProto";
+option java_multiple_files = true;
+option java_package = "com.example.hello";
+
+message BarRequest {
+  string name = 1;
+  Book book = 2;
+}
+
+message BarResponse { string message = 1; }