Adds Enum Supports

examples/query.proto

@@ -45,15 +45,15 @@ message Author {
   string author_password = 3;
   string author_email = 4;
   string author_bio = 5;
-  string author_favourite_section = 6;
+  Section author_favourite_section = 6;
 }
 
 message Post {
   uint32 post_id = 1;
   uint32 post_blog_id = 2;
   uint32 post_author_id = 3;
   google.protobuf.Timestamp post_created_on = 4;
-  string post_section = 5;
+  Section post_section = 5;
   string post_subject = 6;
   string draft = 7;
   string post_body = 8;
@@ -73,6 +73,13 @@ message Tag {
   string tag_name = 2;
 }
 
+enum Section {
+  cooking = 0;
+  painting = 1;
+  woodworking = 2;
+  snowboarding = 3;
+}
+
 message InsertAuthorRequest{
   uint32 id = 1;
   string username = 2;

mapper/mapper.go

@@ -15,9 +15,11 @@ var _ = fmt.Errorf
 var _ = log.Fatal
 var _ = reflect.Append
 
-type mapName string    // Map name corresponds to the proto message name
-type columnName string // Name of the column returned by executing SQL
-type mapType int
+type (
+	mapName    string // Map name corresponds to the proto message name
+	columnName string // Name of the column returned by executing SQL
+	mapType    int
+)
 
 // Map can either be, a top level element (proto response)
 // Association, (nested field) or
@@ -28,6 +30,10 @@ const (
 	Collection
 )
 
+var (
+	EnumVals map[string]map[string]int32
+)
+
 // Representation of SQL response mapping to a proto response message
 // protoc-gen-map generates service server methods which implement interfaces generated by protoc-gen-go
 // each RPC and therefore SQL has corresponding  Mapper
@@ -201,15 +207,17 @@ func generateSqlMap(sqlMap *SqlMap, protoMsg interface{}, columns []string) {
 					strings.ToLower(field.Name):  true,
 				}
 				if _, found := possibleFieldNames[c]; found {
-					sqlMapColumns[columnName(c)] = &ProtoField{
+					protoField := ProtoField{
 						field: &field,
 						index: i,
 					}
+					sqlMapColumns[columnName(c)] = &protoField
 					// remove claimed column
 					columns[j] = columns[len(columns)-1]
 					columns = columns[:len(columns)-1]
 					break
 				}
+
 			}
 		} else if subMapType, isSubMap, err := isSubMap(field); isSubMap == true {
 			if err != nil {
@@ -287,11 +295,20 @@ func isAlowedType(field reflect.StructField) bool {
 		return true
 	} else if kind == reflect.Ptr && allowedTypes[field.Type] {
 		return true
+	} else if isEnum(field) {
+		return true
 	} else {
 		return false
 	}
 }
 
+func isEnum(field reflect.StructField) bool {
+	if field.Type.Kind() == reflect.Int32 && field.Type.Name() != "int32" {
+		return true
+	}
+	return false
+}
+
 // Tests if the struct field is a submap, this is true for nester and repeated fields
 // Repeated fields of primitive types or Timestamp/Empty types are not allowed
 func isSubMap(field reflect.StructField) (string, bool, error) {
@@ -487,6 +504,16 @@ func newSubMapVals(sqlMap *SqlMap, sqlMapVals *SqlMapVals) {
 	}
 }
 
+func RegisterEnums(enums map[string]map[string]int32) {
+	if EnumVals == nil {
+		EnumVals = enums
+	} else {
+		for enumMapName, enumMapVals := range enums {
+			EnumVals[enumMapName] = enumMapVals
+		}
+	}
+}
+
 //If non-breaking issues are found, this function prints them
 func (m *Mapper) Log() {
 	if len(m.Logs) != 0 {

mapper/mapper_test.go

@@ -251,6 +251,21 @@ func TestMappingService(t *testing.T) {
 	if isVerbose {
 		printResp(resp)
 	}
+	resp, err = testMappingClient.SimpleEnum(ctx, &td.EmptyRequest{})
+	if err != nil {
+		log.Printf("stream error: %s\n", err)
+	}
+	if isVerbose {
+		printResp(resp)
+	}
+	resp, err = testMappingClient.NestedEnum(ctx, &td.EmptyRequest{})
+	if err != nil {
+		log.Printf("stream error: %s\n", err)
+	}
+	if isVerbose {
+		log.Printf("  asdasdasdsa: %s\n", err)
+		printResp(resp)
+	}
 	posts, err = testMappingClient.NullResoultsForSubmaps(ctx, &td.EmptyRequest{})
 	if err != nil {
 		log.Fatalf("stream error: %s", err)