compiler/cpp/src/generate/t_go_generator: Embed the LegacyName in the Struct definition

Author: AlexisMontagne

compiler/cpp/src/generate/t_go_generator.cc

@@ -1232,9 +1232,19 @@ void t_go_generator::generate_go_struct_definition(ofstream& out,
   out << indent() << "}" << endl << endl;
   // Default values for optional fields
   out << indent() << "func (p *" << tstruct_name << ") StructDefinition() thrift.StructDefinition {" << endl;
-  out << indent() << " return thrift.StructDefinition{Namespace: \"" << tstruct->get_program()->get_namespace("*") << "\", Name: \"" << tstruct->get_name() << "\"}" << endl;
+  out << indent() << " return thrift.StructDefinition{Namespace: \"" << tstruct->get_current_name()->get_namespace() << "\", Name: \"" << tstruct->get_current_name()->get_name() << "\"}" << endl;
   out << indent() << "}" << endl << endl;
 
+  out << indent() << "func (p *" << tstruct_name << ") LegacyStructDefinitions() []thrift.StructDefinition {" << endl;
+  out << indent() << " return []thrift.StructDefinition{" << endl;
+  std::vector<t_name*> legacy_names = tstruct->get_legacy_names();
+  for (std::vector<t_name*>::iterator it = legacy_names.begin(); it != legacy_names.end(); ++it) {
+    out << indent() << "  {Namespace: \"" << (*it)->get_namespace() << "\", Name:\"" << (*it)->get_name() << "\"}," << endl;
+  }
+  out << indent() << " }" << endl;
+  out << indent() << "}" << endl << endl;
+
+
   for (m_iter = members.begin(); m_iter != members.end(); ++m_iter) {
     string publicized_name;
     t_const_value* def_value;
@@ -1802,6 +1812,22 @@ void t_go_generator::generate_service_interface(t_service* tservice) {
     }
   }
 
+  string singletonServiceName(privatize(tservice->get_name()).append("Singleton"));
+  f_service_ << indent() << "type " << singletonServiceName << " struct {} " << endl << endl;
+
+  f_service_ << indent() << "func (" << singletonServiceName << ") StructDefinition() thrift.StructDefinition {" << endl;
+  f_service_ << indent() << " return thrift.StructDefinition{Namespace: \"" << tservice->get_current_name()->get_namespace() << "\", Name: \"" << tservice->get_current_name()->get_name() << "\"}" << endl;
+  f_service_ << indent() << "}" << endl << endl;
+
+  f_service_ << indent() << "func (" << singletonServiceName << ") LegacyStructDefinitions() []thrift.StructDefinition {" << endl;
+  f_service_ << indent() << " return []thrift.StructDefinition{" << endl;
+  std::vector<t_name*> legacy_names = tservice->get_legacy_names();
+  for (std::vector<t_name*>::iterator it = legacy_names.begin(); it != legacy_names.end(); ++it) {
+    f_service_ << indent() << "  {Namespace: \"" << (*it)->get_namespace() << "\", Name:\"" << (*it)->get_name() << "\"}," << endl;
+  }
+  f_service_ << indent() << " }" << endl;
+  f_service_ << indent() << "}" << endl << endl;
+
   f_service_ << indent() << "type " << interfaceName << " interface {" << extends_if;
   indent_up();
   generate_go_docstring(f_service_, tservice);
@@ -1832,6 +1858,7 @@ void t_go_generator::generate_service_client(t_service* tservice) {
   string extends_client = "";
   string extends_client_new = "";
   string serviceName(publicize(tservice->get_name()));
+  string singletonServiceName(privatize(tservice->get_name()).append("Singleton"));
 
   if (tservice->get_extends() != NULL) {
     extends = type_name(tservice->get_extends());
@@ -1869,9 +1896,9 @@ void t_go_generator::generate_service_client(t_service* tservice) {
              << "Client, error) {" << endl;
 
   indent_up();
-  f_service_ << indent() << "cl, err := p.Build(\""
-             << tservice->get_program()->get_namespace("*") << "\", \""
-             << tservice->get_name() << "\")" << endl << endl;
+  f_service_ << indent() << "cl, err := thrift.BuildClient(p, "
+             << singletonServiceName << "{})" << endl << endl;
+
   f_service_ << indent() << "if err != nil {" << endl;
   indent_up();
   f_service_ << indent() << "return nil, err" << endl;
@@ -2008,10 +2035,12 @@ void t_go_generator::generate_service_server(t_service* tservice) {
   }
 
   string pServiceName(privatize(serviceName));
+  string singletonServiceName(privatize(tservice->get_name()).append("Singleton"));
 
   f_service_ << indent() << "func New" << serviceName << "ProcessorProvider(handler " << serviceName
              << ", provider thrift.TProcessorProvider) (thrift.TProcessor, error) {" << endl;
-  f_service_ << indent() << "p, err := provider.Build(\"" << tservice->get_program()->get_namespace("*") << "\", \"" << tservice->get_name() << "\")" << endl;
+  f_service_ << indent() << "p, err := thrift.BuildProcessor(provider, "
+             << singletonServiceName << "{})" << endl << endl;
   f_service_ << indent() << "if err != nil {" << endl;
   indent_up();
   f_service_ << indent() << "return nil, err" << endl;

lib/go/thrift/definition.go

@@ -53,9 +53,18 @@ func (sd StructDefinition) CanonicalName() string {
 	return fmt.Sprintf("%s.%s", sd.Namespace, sd.Name)
 }
 
+type DefinedStruct interface {
+	StructDefinition() StructDefinition
+}
+
+type FullyDefinedStruct interface {
+	DefinedStruct
+	LegacyStructDefinitions() []StructDefinition
+}
+
 type RegistrableStruct interface {
 	TStruct
-	StructDefinition() StructDefinition
+	DefinedStruct
 }
 
 func RegisterStruct(rs RegistrableStruct) {

lib/go/thrift/provider.go

@@ -1,9 +1,54 @@
 package thrift
 
+import "errors"
+
+var (
+	ErrClientNotDefined    = errors.New("client not defined")
+	ErrProcessorNotDefined = errors.New("processor not defined")
+)
+
 type TClientProvider interface {
 	Build(string, string) (TClient, error)
 }
 
+func BuildClient(cp TClientProvider, s FullyDefinedStruct) (TClient, error) {
+	defs := append(
+		[]StructDefinition{s.StructDefinition()},
+		s.LegacyStructDefinitions()...,
+	)
+
+	for _, def := range defs {
+		switch cl, err := cp.Build(def.Namespace, def.Name); {
+		case err == nil:
+			return cl, nil
+		case errors.Is(err, ErrClientNotDefined):
+		default:
+			return nil, err
+		}
+	}
+
+	return nil, ErrClientNotDefined
+}
+
 type TProcessorProvider interface {
 	Build(string, string) (TProcessor, error)
 }
+
+func BuildProcessor(pp TProcessorProvider, s FullyDefinedStruct) (TProcessor, error) {
+	defs := append(
+		[]StructDefinition{s.StructDefinition()},
+		s.LegacyStructDefinitions()...,
+	)
+
+	for _, def := range defs {
+		switch cl, err := pp.Build(def.Namespace, def.Name); {
+		case err == nil:
+			return cl, nil
+		case errors.Is(err, ErrProcessorNotDefined):
+		default:
+			return nil, err
+		}
+	}
+
+	return nil, ErrProcessorNotDefined
+}