Fix Multiple External Type Usage in One Message (#8)

* update example/user_add_comment.proto

* make created_at and updated_at optional

* avoid message definition conflicts

* update sample output

* revert the original name of a message

* make debts order predictable

* fix test

content_builder.go

@@ -3,6 +3,7 @@ package main
 import (
 	"errors"
 	"fmt"
+	"regexp"
 	"strings"
 
 	"google.golang.org/protobuf/types/descriptorpb"
@@ -33,44 +34,77 @@ func (b *contentBuilder) build(protoFile *descriptorpb.FileDescriptorProto) (str
 }
 
 func (b *contentBuilder) buildMessage(message *descriptorpb.DescriptorProto, level int) {
-	b.output.WriteString(buildIndent(level) + "message " + message.GetName() + " {\n")
+	fmt.Fprintf(b.output, "%smessage %s {\n", buildIndent(level), message.GetName())
+	debts := []string(nil)
 	for _, field := range message.GetField() {
-		b.buildField(field, level+1)
+		debts = append(debts, b.buildField(field, level+1))
 	}
-	b.output.WriteString(buildIndent(level) + "}\n")
+	b.payDebts(debts, level+1)
+	fmt.Fprintf(b.output, "%s}\n", buildIndent(level))
 }
 
-func (b *contentBuilder) buildField(field *descriptorpb.FieldDescriptorProto, level int) {
-	fieldType := strings.ToLower(strings.TrimPrefix(field.GetType().String(), "TYPE_"))
-	if field.GetType() == descriptorpb.FieldDescriptorProto_TYPE_MESSAGE {
-		fieldType = b.buildFieldType(field.GetTypeName(), level)
-	}
-	b.output.WriteString(buildIndent(level))
-	b.buildFieldLabel(field.GetLabel())
-	fmt.Fprintf(b.output, "%s %s = %d;\n", fieldType, field.GetName(), field.GetNumber())
+func (b *contentBuilder) buildField(field *descriptorpb.FieldDescriptorProto, level int) string {
+	fieldType, debt := b.getFieldType(field)
+	fmt.Fprintf(b.output, "%s%s%s %s = %d;\n",
+		buildIndent(level),
+		b.getLabelPrefix(field.GetLabel()),
+		fieldType,
+		field.GetName(),
+		field.GetNumber(),
+	)
+	return debt
 }
 
-func (b *contentBuilder) buildFieldType(typeName string, level int) string {
-	if b.messageEncoding == "json" {
-		if typeName, ok := wktMapping[typeName]; ok {
-			return typeName
-		}
+func (b *contentBuilder) getFieldType(field *descriptorpb.FieldDescriptorProto) (string, string) {
+	if field.GetType() != descriptorpb.FieldDescriptorProto_TYPE_MESSAGE {
+		return strings.ToLower(strings.TrimPrefix(field.GetType().String(), "TYPE_")), ""
 	}
-
-	b.output.WriteString("\n")
-	b.buildMessage(b.messageTypes[typeName], level)
-	b.output.WriteString("\n")
-	return typeName[strings.LastIndexByte(typeName, '.')+1:]
+	fullMessageName := field.GetTypeName()
+	wkt := wktMapping[fullMessageName]
+	if b.messageEncoding == "json" && wkt != "" {
+		return wkt, ""
+	}
+	return getLocalName(fullMessageName), fullMessageName
 }
 
-func (b *contentBuilder) buildFieldLabel(label descriptorpb.FieldDescriptorProto_Label) {
+func (b *contentBuilder) getLabelPrefix(label descriptorpb.FieldDescriptorProto_Label) string {
 	if label == descriptorpb.FieldDescriptorProto_LABEL_REPEATED {
-		b.output.WriteString("repeated ")
-	} else if b.schemaSyntax == "proto2" {
-		b.output.WriteString(strings.ToLower(strings.TrimPrefix(label.String(), "LABEL_")) + " ")
+		return "repeated "
+	}
+	if b.schemaSyntax == "proto2" {
+		return strings.ToLower(strings.TrimPrefix(label.String(), "LABEL_")) + " "
 	}
+	return ""
+}
+
+func (b *contentBuilder) payDebts(debts []string, level int) {
+	payedDebts := make(map[string]bool)
+	for _, debt := range debts {
+		if debt != "" && !payedDebts[debt] {
+			b.payDebt(debt, level)
+			payedDebts[debt] = true
+		}
+	}
+}
+
+func (b *contentBuilder) payDebt(debt string, level int) {
+	message := b.messageTypes[debt]
+	defer func(originalName *string) { message.Name = originalName }(message.Name)
+	localName := getLocalName(debt)
+	message.Name = &localName
+	b.output.WriteString("\n")
+	b.buildMessage(message, level)
 }
 
 func buildIndent(level int) string {
 	return strings.Repeat("  ", level)
 }
+
+var localNamePattern = regexp.MustCompile(`\..`)
+
+func getLocalName(fullMessageName string) string {
+	return localNamePattern.ReplaceAllStringFunc(
+		fullMessageName,
+		func(s string) string { return strings.ToUpper(s[1:]) },
+	)
+}

example/user_add_comment.pps

@@ -1,34 +1,37 @@
 syntax = "proto2";
 
 message UserAddComment {
+  required ExampleUserAddCommentUser user = 1;
+  required string comment = 2;
+  repeated ExampleCommonLabel labels = 3;
+  required GoogleProtobufTimestamp timestamp = 101;
 
-  message User {
+  message ExampleUserAddCommentUser {
     required string first_name = 1;
     optional string last_name = 2;
     optional bytes avatar = 3;
+    optional ExampleUserAddCommentUserLocation location = 4;
+    optional GoogleProtobufTimestamp created_at = 5;
+    optional GoogleProtobufTimestamp updated_at = 6;
 
-    message Location {
+    message ExampleUserAddCommentUserLocation {
       required double longitude = 1;
       required double latitude = 2;
     }
 
-    optional Location location = 4;
+    message GoogleProtobufTimestamp {
+      optional int64 seconds = 1;
+      optional int32 nanos = 2;
+    }
   }
 
-  required User user = 1;
-  required string comment = 2;
-
-  message Label {
+  message ExampleCommonLabel {
     optional string key = 1;
     optional string value = 2;
   }
 
-  repeated Label labels = 3;
-
-  message Timestamp {
+  message GoogleProtobufTimestamp {
     optional int64 seconds = 1;
     optional int32 nanos = 2;
   }
-
-  required Timestamp timestamp = 101;
 }

example/user_add_comment.proto

@@ -6,22 +6,22 @@ import "example/common/label.proto";
 import "google/protobuf/timestamp.proto";
 
 message UserAddComment {
+  required User user = 1;
+  required string comment = 2;
+  repeated example.common.Label labels = 3;
+  required google.protobuf.Timestamp timestamp = 101;
+
   message User {
     required string first_name = 1;
     optional string last_name = 2;
     optional bytes avatar = 3;
+    optional Location location = 4;
+    optional google.protobuf.Timestamp created_at = 5;
+    optional google.protobuf.Timestamp updated_at = 6;
 
     message Location {
       required double longitude = 1;
       required double latitude = 2;
     }
-
-    optional Location location = 4;
   }
-
-  required User user = 1;
-  required string comment = 2;
-  repeated example.common.Label labels = 3;
-
-  required google.protobuf.Timestamp timestamp = 101;
 }

test/user_add_comment.out

@@ -1,35 +1,38 @@
-z�
-example/user_add_comment.ppsz�syntax = "proto2";
+z�
+example/user_add_comment.ppsz�syntax = "proto2";
 
 message UserAddComment {
+  required ExampleUserAddCommentUser user = 1;
+  required string comment = 2;
+  repeated ExampleCommonLabel labels = 3;
+  required GoogleProtobufTimestamp timestamp = 101;
 
-  message User {
+  message ExampleUserAddCommentUser {
     required string first_name = 1;
     optional string last_name = 2;
     optional bytes avatar = 3;
+    optional ExampleUserAddCommentUserLocation location = 4;
+    optional GoogleProtobufTimestamp created_at = 5;
+    optional GoogleProtobufTimestamp updated_at = 6;
 
-    message Location {
+    message ExampleUserAddCommentUserLocation {
       required double longitude = 1;
       required double latitude = 2;
     }
 
-    optional Location location = 4;
+    message GoogleProtobufTimestamp {
+      optional int64 seconds = 1;
+      optional int32 nanos = 2;
+    }
   }
 
-  required User user = 1;
-  required string comment = 2;
-
-  message Label {
+  message ExampleCommonLabel {
     optional string key = 1;
     optional string value = 2;
   }
 
-  repeated Label labels = 3;
-
-  message Timestamp {
+  message GoogleProtobufTimestamp {
     optional int64 seconds = 1;
     optional int32 nanos = 2;
   }
-
-  required Timestamp timestamp = 101;
 }