Support primitive type with format in response

operation.go

@@ -978,7 +978,15 @@ func (operation *Operation) parseAPIObjectSchema(commentLine, schemaType, refTyp
 
 		return spec.ArrayProperty(schema), nil
 	default:
-		return PrimitiveSchema(schemaType), nil
+		schema := PrimitiveSchema(schemaType)
+		if refType != schemaType {
+			//refer to https://swagger.io/specification/v2/#dataTypeFormat
+			if !validPrimitiveFormat[schemaType][refType] {
+				return nil, fmt.Errorf("invalid format %s of type %s", refType, schemaType)
+			}
+			schema.Format = refType
+		}
+		return schema, nil
 	}
 }
 

operation_test.go

@@ -234,7 +234,7 @@ func TestOperation_ParseResponseWithDefault(t *testing.T) {
 
 	assert.Equal(t, "An empty response", operation.Responses.Default.Description)
 
-	comment = `@Success 200,default {string} Response "A response"`
+	comment = `@Success 200,default {string} string "A response"`
 	operation = NewOperation(nil)
 
 	err = operation.ParseComment(comment, nil)
@@ -244,6 +244,33 @@ func TestOperation_ParseResponseWithDefault(t *testing.T) {
 	assert.Equal(t, "A response", operation.Responses.StatusCodeResponses[200].Description)
 }
 
+func TestParseResponsePrimitiveTypeWithFormat(t *testing.T) {
+	t.Parallel()
+
+	comment := `@Success 200 {integer} int16 "response with format"`
+	operation := NewOperation(nil)
+	err := operation.ParseComment(comment, nil)
+	assert.Error(t, err)
+
+	comment = `@Success 200 {integer} int32 "response with format"`
+	operation = NewOperation(nil)
+	err = operation.ParseComment(comment, nil)
+	assert.NoError(t, err)
+	b, _ := json.MarshalIndent(operation, "", "    ")
+	expected := `{
+    "responses": {
+        "200": {
+            "description": "response with format",
+            "schema": {
+                "type": "integer",
+                "format": "int32"
+            }
+        }
+    }
+}`
+	assert.Equal(t, expected, string(b))
+}
+
 func TestParseResponseSuccessCommentWithEmptyResponse(t *testing.T) {
 	t.Parallel()
 

schema.go

@@ -36,6 +36,12 @@ const (
 	IgnoreNameOverridePrefix = '$'
 )
 
+var validPrimitiveFormat = map[string]map[string]bool{
+	INTEGER: {"int32": true, "int64": true},
+	NUMBER:  {"float": true, "double": true},
+	STRING:  {"byte": true, "binary": true, "date": true, "date-time": true, "password": true},
+}
+
 // CheckSchemaType checks if typeName is not a name of primitive type.
 func CheckSchemaType(typeName string) error {
 	if !IsPrimitiveType(typeName) {

testdata/struct_comment/api/api.go

@@ -7,7 +7,7 @@ import "net/http"
 // @Accept  json
 // @Produce  json
 // @Param   post_id      path   int     true  "Some ID" Format(int64)
-// @Success 200 {string} web.Post
+// @Success 200 {string} string ""
 // @Failure 400 {object} web.APIError "We need ID!!"
 // @Failure 404 {object} web.APIError "Can not find ID"
 // @Router /posts/{post_id} [get]