From 1e52c243a95ffc51f032d458cfc33720c7c367b0 Mon Sep 17 00:00:00 2001
From: Andres Correa Casablanca <andreu.casablanca@join.com>
Date: Fri, 16 Apr 2021 08:08:11 +0200
Subject: [PATCH] feat: extract final client interface

---
 internal/generator/runer_generate_service.go | 58 +++++++++++++++++++-
 tests/__tests__/v2/generated/Test.ts         | 27 ++++++++-
 2 files changed, 83 insertions(+), 2 deletions(-)

diff --git a/internal/generator/runer_generate_service.go b/internal/generator/runer_generate_service.go
index 016a483..7bfa6db 100644
--- a/internal/generator/runer_generate_service.go
+++ b/internal/generator/runer_generate_service.go
@@ -12,6 +12,7 @@ func (r *Runner) generateTypescriptServiceDefinitions(generatedFileStream *proto
 	for _, serviceSpec := range protoFile.Proto.GetService() {
 		r.generateTypescriptServiceImplementationInterface(generatedFileStream, serviceSpec)
 		r.generateTypescriptServiceDefinition(generatedFileStream, serviceSpec)
+		r.generateTypescriptClientInterface(generatedFileStream, serviceSpec)
 		r.generateTypescriptClient(generatedFileStream, serviceSpec)
 	}
 }
@@ -87,12 +88,67 @@ func (r *Runner) generateTypescriptServiceDefinitionMethod(generatedFileStream *
 	r.P(generatedFileStream, "},")
 }
 
+func (r *Runner) generateTypescriptClientInterface(generatedFileStream *protogen.GeneratedFile, serviceSpec *descriptorpb.ServiceDescriptorProto) {
+	r.P(
+		generatedFileStream,
+		"export interface I"+strcase.ToCamel(serviceSpec.GetName())+"Client",
+		"extends joinGRPC.IClient<grpc.ServiceDefinition<I"+strcase.ToCamel(serviceSpec.GetName())+"ServiceImplementation>> ",
+		", joinGRPC.IExtendedClient<I"+strcase.ToCamel(serviceSpec.GetName())+"ServiceImplementation> {",
+	)
+	r.indentLevel += 2
+
+	for _, methodSpec := range serviceSpec.GetMethod() {
+		r.generateTypescriptClientInterfaceMethod(generatedFileStream, serviceSpec, methodSpec)
+	}
+
+	r.indentLevel -= 2
+	r.P(generatedFileStream, "}\n")
+}
+
+func (r *Runner) generateTypescriptClientInterfaceMethod(generatedFileStream *protogen.GeneratedFile, serviceSpec *descriptorpb.ServiceDescriptorProto, methodSpec *descriptorpb.MethodDescriptorProto) {
+	// Function's Signature
+	methodName := strcase.ToCamel(methodSpec.GetName())
+	r.P(generatedFileStream, methodName+"(")
+	r.indentLevel += 2
+
+	inputTypeName := methodSpec.GetInputType()
+	inputInterface := r.getEnumOrMessageTypeName(inputTypeName, true)
+	outputTypeName := methodSpec.GetOutputType()
+	outputInterface := r.getEnumOrMessageTypeName(outputTypeName, true)
+
+	clientStream := methodSpec.GetClientStreaming()
+	serverStrean := methodSpec.GetServerStreaming()
+
+	if !clientStream {
+		r.P(generatedFileStream, "request: "+inputInterface+",")
+	}
+
+	r.P(generatedFileStream,
+		"metadata?: Record<string, string>,",
+		"options?: grpc.CallOptions,",
+	)
+
+	var returnType string
+	if clientStream && serverStrean {
+		returnType = "grpc.ClientDuplexStream<" + inputInterface + ", " + outputInterface + ">"
+	} else if !clientStream && !serverStrean {
+		returnType = "joinGRPC.IUnaryRequest<" + outputInterface + ">"
+	} else if clientStream {
+		returnType = "joinGRPC.IClientStreamRequest<" + inputInterface + ", " + outputInterface + ">"
+	} else { // if serverStream
+		returnType = "grpc.ClientReadableStream<" + outputInterface + ">"
+	}
+
+	r.indentLevel -= 2
+	r.P(generatedFileStream, "): "+returnType)
+}
+
 func (r *Runner) generateTypescriptClient(generatedFileStream *protogen.GeneratedFile, serviceSpec *descriptorpb.ServiceDescriptorProto) {
 	r.P(
 		generatedFileStream,
 		"export class "+strcase.ToCamel(serviceSpec.GetName())+"Client",
 		"extends joinGRPC.Client<grpc.ServiceDefinition<I"+strcase.ToCamel(serviceSpec.GetName())+"ServiceImplementation>> ",
-		"implements joinGRPC.IExtendedClient<I"+strcase.ToCamel(serviceSpec.GetName())+"ServiceImplementation> {",
+		"implements I"+strcase.ToCamel(serviceSpec.GetName())+"Client {",
 	)
 	r.indentLevel += 2
 
diff --git a/tests/__tests__/v2/generated/Test.ts b/tests/__tests__/v2/generated/Test.ts
index 64994ad..57e52f3 100644
--- a/tests/__tests__/v2/generated/Test.ts
+++ b/tests/__tests__/v2/generated/Test.ts
@@ -485,9 +485,34 @@ export namespace Foo {
     },
   }
 
+  export interface IUsersClient
+    extends joinGRPC.IClient<
+        grpc.ServiceDefinition<IUsersServiceImplementation>
+      >,
+      joinGRPC.IExtendedClient<IUsersServiceImplementation> {
+    Find(
+      request: IRequest,
+      metadata?: Record<string, string>,
+      options?: grpc.CallOptions
+    ): joinGRPC.IUnaryRequest<Common_Common.IOtherPkgMessage>
+    FindClientStream(
+      metadata?: Record<string, string>,
+      options?: grpc.CallOptions
+    ): joinGRPC.IClientStreamRequest<IRequest, Common_Common.IOtherPkgMessage>
+    FindServerStream(
+      request: IRequest,
+      metadata?: Record<string, string>,
+      options?: grpc.CallOptions
+    ): grpc.ClientReadableStream<Common_Common.IOtherPkgMessage>
+    FindBidiStream(
+      metadata?: Record<string, string>,
+      options?: grpc.CallOptions
+    ): grpc.ClientDuplexStream<IRequest, Common_Common.IOtherPkgMessage>
+  }
+
   export class UsersClient
     extends joinGRPC.Client<grpc.ServiceDefinition<IUsersServiceImplementation>>
-    implements joinGRPC.IExtendedClient<IUsersServiceImplementation> {
+    implements IUsersClient {
     public Find(
       request: IRequest,
       metadata?: Record<string, string>,