chore: better merging logic

Author: amirsalarsafaei

protoc-gen-openapiv3/internal/genopenapiv3/merge.go

@@ -53,14 +53,12 @@ func MergeOpenAPISpecs(specs ...*openapi3.T) (*openapi3.T, error) {
 if spec.Paths != nil {
 for path, pathItem := range spec.Paths.Map() {
 if existingPathItem, exists := merged.Paths.Map()[path]; exists {
-mergedPathItem, err := mergePathItems(existingPathItem, pathItem)
+err := mergePathItems(existingPathItem, pathItem)
 if err != nil {
 return nil, fmt.Errorf("error merging path %s from spec %d: %v", path, i, err)
 }
 
-merged.Paths.Set(path, mergedPathItem)
 } else {
-
 merged.Paths.Set(path, pathItem)
 }
 }
@@ -89,89 +87,49 @@ func MergeOpenAPISpecs(specs ...*openapi3.T) (*openapi3.T, error) {
 return merged, nil
 }
 
-// mergePathItems merges two path items, combining their operations
-func mergePathItems(existing, new *openapi3.PathItem) (*openapi3.PathItem, error) {
-merged := &openapi3.PathItem{
-Ref: existing.Ref,
-Summary: existing.Summary,
-Description: existing.Description,
-Servers: existing.Servers,
-Parameters: existing.Parameters,
-}
-
-// Copy existing operations
-if existing.Get != nil {
-merged.Get = existing.Get
-}
-if existing.Put != nil {
-merged.Put = existing.Put
-}
-if existing.Post != nil {
-merged.Post = existing.Post
-}
-if existing.Delete != nil {
-merged.Delete = existing.Delete
-}
-if existing.Options != nil {
-merged.Options = existing.Options
-}
-if existing.Head != nil {
-merged.Head = existing.Head
-}
-if existing.Patch != nil {
-merged.Patch = existing.Patch
-}
-if existing.Trace != nil {
-merged.Trace = existing.Trace
-}
-
-// Add new operations (overwrite existing operations with new ones)
+func mergePathItems(existing, new *openapi3.PathItem) error {
+// TODO: error and log warn when new one overrides existing one
 if new.Get != nil {
-merged.Get = new.Get
+existing.Get = new.Get
 }
 if new.Put != nil {
-merged.Put = new.Put
+existing.Put = new.Put
 }
 if new.Post != nil {
-merged.Post = new.Post
+existing.Post = new.Post
 }
 if new.Delete != nil {
-merged.Delete = new.Delete
+existing.Delete = new.Delete
 }
 if new.Options != nil {
-merged.Options = new.Options
+existing.Options = new.Options
 }
 if new.Head != nil {
-merged.Head = new.Head
+existing.Head = new.Head
 }
 if new.Patch != nil {
-merged.Patch = new.Patch
+existing.Patch = new.Patch
 }
 if new.Trace != nil {
-merged.Trace = new.Trace
+existing.Trace = new.Trace
 }
 
-// Merge parameters
 if new.Parameters != nil {
-merged.Parameters = append(merged.Parameters, new.Parameters...)
+existing.Parameters = mergeParameters(existing.Parameters, new.Parameters)
 }
 
-// Merge servers
 if new.Servers != nil {
-merged.Servers = append(merged.Servers, new.Servers...)
+existing.Servers = append(existing.Servers, new.Servers...)
 }
 
-return merged, nil
+return nil
 }
 
-// mergeComponents merges components from source into target
 func mergeComponents(target, source *openapi3.Components, specIndex int) error {
-// Merge schemas
 if source.Schemas != nil {
 maps.Copy(target.Schemas, source.Schemas)
 }
 
-// Merge parameters
 if source.Parameters != nil {
 for name, param := range source.Parameters {
 if _, exists := target.Parameters[name]; exists {
@@ -181,7 +139,6 @@ func mergeComponents(target, source *openapi3.Components, specIndex int) error {
 }
 }
 
-// Merge headers
 if source.Headers != nil {
 for name, header := range source.Headers {
 if _, exists := target.Headers[name]; exists {
@@ -191,7 +148,6 @@ func mergeComponents(target, source *openapi3.Components, specIndex int) error {
 }
 }
 
-// Merge request bodies
 if source.RequestBodies != nil {
 for name, requestBody := range source.RequestBodies {
 if _, exists := target.RequestBodies[name]; exists {
@@ -201,7 +157,6 @@ func mergeComponents(target, source *openapi3.Components, specIndex int) error {
 }
 }
 
-// Merge responses
 if source.Responses != nil {
 for name, response := range source.Responses {
 if _, exists := target.Responses[name]; exists {
@@ -211,7 +166,6 @@ func mergeComponents(target, source *openapi3.Components, specIndex int) error {
 }
 }
 
-// Merge security schemes
 if source.SecuritySchemes != nil {
 for name, securityScheme := range source.SecuritySchemes {
 if _, exists := target.SecuritySchemes[name]; exists {
@@ -221,7 +175,6 @@ func mergeComponents(target, source *openapi3.Components, specIndex int) error {
 }
 }
 
-// Merge examples
 if source.Examples != nil {
 for name, example := range source.Examples {
 if _, exists := target.Examples[name]; exists {
@@ -231,7 +184,6 @@ func mergeComponents(target, source *openapi3.Components, specIndex int) error {
 }
 }
 
-// Merge links
 if source.Links != nil {
 for name, link := range source.Links {
 if _, exists := target.Links[name]; exists {
@@ -241,7 +193,6 @@ func mergeComponents(target, source *openapi3.Components, specIndex int) error {
 }
 }
 
-// Merge callbacks
 if source.Callbacks != nil {
 for name, callback := range source.Callbacks {
 if _, exists := target.Callbacks[name]; exists {
@@ -253,3 +204,48 @@ func mergeComponents(target, source *openapi3.Components, specIndex int) error {
 
 return nil
 }
+
+func mergeParameters(existing, new openapi3.Parameters) openapi3.Parameters {
+if len(existing) == 0 {
+return new
+}
+if len(new) == 0 {
+return existing
+}
+
+paramMap := make(map[string]*openapi3.ParameterRef)
+var result openapi3.Parameters
+
+for _, param := range existing {
+if param != nil && param.Value != nil {
+key := getParameterKey(param.Value)
+paramMap[key] = param
+result = append(result, param)
+}
+}
+
+for _, param := range new {
+if param != nil && param.Value != nil {
+key := getParameterKey(param.Value)
+if existingParam, exists := paramMap[key]; exists {
+for i, resultParam := range result {
+if resultParam == existingParam {
+result[i] = param
+break
+}
+}
+paramMap[key] = param
+} else {
+// Add new parameter
+paramMap[key] = param
+result = append(result, param)
+}
+}
+}
+
+return result
+}
+
+func getParameterKey(param *openapi3.Parameter) string {
+return param.Name + ":" + param.In
+}