Add operationId uniqueness check

parser.go

@@ -141,7 +141,7 @@ func (parser *Parser) ParseAPI(searchDir string, mainAPIFile string) error {
 		Printf("warning: failed to get package name in dir: %s, error: %s", searchDir, err.Error())
 	}
 
-	if err := parser.getAllGoFileInfo(packageDir, searchDir); err != nil {
+	if err = parser.getAllGoFileInfo(packageDir, searchDir); err != nil {
 		return err
 	}
 
@@ -168,7 +168,7 @@ func (parser *Parser) ParseAPI(searchDir string, mainAPIFile string) error {
 		}
 	}
 
-	if err := parser.ParseGeneralAPIInfo(absMainAPIFilePath); err != nil {
+	if err = parser.ParseGeneralAPIInfo(absMainAPIFilePath); err != nil {
 		return err
 	}
 
@@ -177,7 +177,11 @@ func (parser *Parser) ParseAPI(searchDir string, mainAPIFile string) error {
 		return err
 	}
 
-	return parser.packages.RangeFiles(parser.ParseRouterAPIInfo)
+	if err = parser.packages.RangeFiles(parser.ParseRouterAPIInfo); err != nil {
+		return err
+	}
+
+  return parser.checkOperationIDUniqueness()
 }
 
 func getPkgName(searchDir string) (string, error) {
@@ -1262,6 +1266,69 @@ func (parser *Parser) parseFile(packageDir, path string, src interface{}) error
 	return nil
 }
 
+func (parser *Parser) checkOperationIDUniqueness() error {
+	// operationsIds contains all operationId annotations to check it's unique
+	operationsIds := make(map[string]string)
+	saveOperationID := func(operationID, currentPath string) error {
+		if operationID == "" {
+			return nil
+		}
+		if previousPath, ok := operationsIds[operationID]; ok {
+			return fmt.Errorf(
+				"duplicated @id annotation '%s' found in '%s', previously declared in: '%s'",
+				operationID, currentPath, previousPath)
+		}
+		operationsIds[operationID] = currentPath
+		return nil
+	}
+
+	for path, itm := range parser.swagger.Paths.Paths {
+		if itm.Get != nil {
+			currentPath := fmt.Sprintf("%s %s", "GET", path)
+			if err := saveOperationID(itm.Get.ID, currentPath); err != nil {
+				return err
+			}
+		}
+		if itm.Put != nil {
+			currentPath := fmt.Sprintf("%s %s", "PUT", path)
+			if err := saveOperationID(itm.Put.ID, currentPath); err != nil {
+				return err
+			}
+		}
+		if itm.Post != nil {
+			currentPath := fmt.Sprintf("%s %s", "POST", path)
+			if err := saveOperationID(itm.Post.ID, currentPath); err != nil {
+				return err
+			}
+		}
+		if itm.Delete != nil {
+			currentPath := fmt.Sprintf("%s %s", "DELETE", path)
+			if err := saveOperationID(itm.Delete.ID, currentPath); err != nil {
+				return err
+			}
+		}
+		if itm.Options != nil {
+			currentPath := fmt.Sprintf("%s %s", "OPTIONS", path)
+			if err := saveOperationID(itm.Options.ID, currentPath); err != nil {
+				return err
+			}
+		}
+		if itm.Head != nil {
+			currentPath := fmt.Sprintf("%s %s", "HEAD", path)
+			if err := saveOperationID(itm.Head.ID, currentPath); err != nil {
+				return err
+			}
+		}
+		if itm.Patch != nil {
+			currentPath := fmt.Sprintf("%s %s", "PATCH", path)
+			if err := saveOperationID(itm.Patch.ID, currentPath); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
 // Skip returns filepath.SkipDir error if match vendor and hidden folder
 func (parser *Parser) Skip(path string, f os.FileInfo) error {
 	if f.IsDir() {

parser_test.go

@@ -1540,6 +1540,15 @@ func TestParseNested(t *testing.T) {
 	assert.Equal(t, string(expected), string(b))
 }
 
+func TestParseDuplicated(t *testing.T) {
+	searchDir := "testdata/duplicated"
+	mainAPIFile := "main.go"
+	p := New()
+	p.ParseDependency = true
+	err := p.ParseAPI(searchDir, mainAPIFile)
+	assert.Errorf(t, err, "duplicated @id declarations successfully found")
+}
+
 func TestParser_ParseStructArrayObject(t *testing.T) {
 	src := `
 package api

testdata/duplicated/api/api.go

@@ -0,0 +1,17 @@
+package api
+
+import (
+	"github.com/gin-gonic/gin"
+)
+
+// @Description get Foo
+// @ID get-foo
+// @Success 200 {string} string
+// @Router /testapi/get-foo [get]
+func GetFoo(c *gin.Context) {}
+
+// @Description post Bar
+// @ID get-foo
+// @Success 200 {string} string
+// @Router /testapi/post-bar [post]
+func PostBar(c *gin.Context) {}

testdata/duplicated/main.go

@@ -0,0 +1,22 @@
+package composition
+
+import (
+	"github.com/gin-gonic/gin"
+
+	"github.com/swaggo/swag/testdata/duplicated/api"
+)
+
+// @title Swagger Example API
+// @version 1.0
+// @description This is a sample server
+// @termsOfService http://swagger.io/terms/
+
+// @host petstore.swagger.io
+// @BasePath /v2
+
+func main() {
+	r := gin.New()
+	r.GET("/testapi/get-foo", api.GetFoo)
+	r.POST("/testapi/post-bar", api.PostBar)
+	r.Run()
+}