Generated reflection service code (#1659)

Motivation:

In order to develop the Reflection Service, the specific proto file should be included in the module and
the service code generated from it.

Modifications:

Created the module for the Reflection Service, added the proto file, updated the Package.swift
to include the module, updated the Makefile to inlude targets for generating the server code,
created the ReflectionProvider.

Result:

The Reflection Service can now be implemented.

Author: stefanadranca

Makefile

@@ -131,6 +131,22 @@ ${SERIALIZATION_GRPC_REFLECTION}: ${ECHO_PROTO} ${PROTOC_GEN_GRPC_SWIFT}
 .PHONY:
 generate-reflection-data: ${SERIALIZATION_GRPC_REFLECTION}
 
+REFLECTION_PROTO=Sources/GRPCReflectionService/Model/reflection.proto
+REFLECTION_PB=$(REFLECTION_PROTO:.proto=.pb.swift)
+REFLECTION_GRPC=$(REFLECTION_PROTO:.proto=.grpc.swift)
+
+# For Reflection we'll generate only the Server code.
+${REFLECTION_GRPC}: ${REFLECTION_PROTO} ${PROTOC_GEN_GRPC_SWIFT}
+	protoc $< \
+		--proto_path=$(dir $<) \
+		--plugin=${PROTOC_GEN_GRPC_SWIFT} \
+		--grpc-swift_opt=Client=false \
+		--grpc-swift_out=$(dir $<)
+
+# Generates protobufs and gRPC server for the Reflection Service
+.PHONY:
+generate-reflection: ${REFLECTION_PB} ${REFLECTION_GRPC}
+
 ### Testing ####################################################################
 
 # Normal test suite.

Package.swift

@@ -89,6 +89,7 @@ extension Target.Dependency {
   static let interopTestModels: Self = .target(name: "GRPCInteroperabilityTestModels")
   static let interopTestImplementation: Self =
     .target(name: "GRPCInteroperabilityTestsImplementation")
+  static let reflectionService: Self = .target(name: "GRPCReflectionService")
 
   // Product dependencies
   static let argumentParser: Self = .product(
@@ -428,6 +429,19 @@ extension Target {
       "README.md",
     ]
   )
+
+  static let reflectionService: Target = .target(
+    name: "GRPCReflectionService",
+    dependencies: [
+      .grpc,
+      .nio,
+      .protobuf,
+    ],
+    path: "Sources/GRPCReflectionService",
+    exclude: [
+      "Model/reflection.proto",
+    ]
+  )
 }
 
 // MARK: - Products
@@ -471,6 +485,7 @@ let package = Package(
     .cgrpcZlib,
     .protocGenGRPCSwift,
     .grpcSwiftPlugin,
+    .reflectionService,
 
     // Tests etc.
     .grpcTests,

Sources/GRPCReflectionService/Model/reflection.grpc.swift

@@ -0,0 +1,122 @@
+//
+// DO NOT EDIT.
+// swift-format-ignore-file
+//
+// Generated by the protocol buffer compiler.
+// Source: reflection.proto
+//
+import GRPC
+import NIO
+import NIOConcurrencyHelpers
+import SwiftProtobuf
+
+
+/// To build a server, implement a class that conforms to this protocol.
+internal protocol Reflection_ServerReflectionProvider: CallHandlerProvider {
+  var interceptors: Reflection_ServerReflectionServerInterceptorFactoryProtocol? { get }
+
+  /// The reflection service is structured as a bidirectional stream, ensuring
+  /// all related requests go to a single server.
+  func serverReflectionInfo(context: StreamingResponseCallContext<Reflection_ServerReflectionResponse>) -> EventLoopFuture<(StreamEvent<Reflection_ServerReflectionRequest>) -> Void>
+}
+
+extension Reflection_ServerReflectionProvider {
+  internal var serviceName: Substring {
+    return Reflection_ServerReflectionServerMetadata.serviceDescriptor.fullName[...]
+  }
+
+  /// Determines, calls and returns the appropriate request handler, depending on the request's method.
+  /// Returns nil for methods not handled by this service.
+  internal func handle(
+    method name: Substring,
+    context: CallHandlerContext
+  ) -> GRPCServerHandlerProtocol? {
+    switch name {
+    case "ServerReflectionInfo":
+      return BidirectionalStreamingServerHandler(
+        context: context,
+        requestDeserializer: ProtobufDeserializer<Reflection_ServerReflectionRequest>(),
+        responseSerializer: ProtobufSerializer<Reflection_ServerReflectionResponse>(),
+        interceptors: self.interceptors?.makeServerReflectionInfoInterceptors() ?? [],
+        observerFactory: self.serverReflectionInfo(context:)
+      )
+
+    default:
+      return nil
+    }
+  }
+}
+
+/// To implement a server, implement an object which conforms to this protocol.
+@available(macOS 10.15, iOS 13, tvOS 13, watchOS 6, *)
+internal protocol Reflection_ServerReflectionAsyncProvider: CallHandlerProvider, Sendable {
+  static var serviceDescriptor: GRPCServiceDescriptor { get }
+  var interceptors: Reflection_ServerReflectionServerInterceptorFactoryProtocol? { get }
+
+  /// The reflection service is structured as a bidirectional stream, ensuring
+  /// all related requests go to a single server.
+  func serverReflectionInfo(
+    requestStream: GRPCAsyncRequestStream<Reflection_ServerReflectionRequest>,
+    responseStream: GRPCAsyncResponseStreamWriter<Reflection_ServerReflectionResponse>,
+    context: GRPCAsyncServerCallContext
+  ) async throws
+}
+
+@available(macOS 10.15, iOS 13, tvOS 13, watchOS 6, *)
+extension Reflection_ServerReflectionAsyncProvider {
+  internal static var serviceDescriptor: GRPCServiceDescriptor {
+    return Reflection_ServerReflectionServerMetadata.serviceDescriptor
+  }
+
+  internal var serviceName: Substring {
+    return Reflection_ServerReflectionServerMetadata.serviceDescriptor.fullName[...]
+  }
+
+  internal var interceptors: Reflection_ServerReflectionServerInterceptorFactoryProtocol? {
+    return nil
+  }
+
+  internal func handle(
+    method name: Substring,
+    context: CallHandlerContext
+  ) -> GRPCServerHandlerProtocol? {
+    switch name {
+    case "ServerReflectionInfo":
+      return GRPCAsyncServerHandler(
+        context: context,
+        requestDeserializer: ProtobufDeserializer<Reflection_ServerReflectionRequest>(),
+        responseSerializer: ProtobufSerializer<Reflection_ServerReflectionResponse>(),
+        interceptors: self.interceptors?.makeServerReflectionInfoInterceptors() ?? [],
+        wrapping: { try await self.serverReflectionInfo(requestStream: $0, responseStream: $1, context: $2) }
+      )
+
+    default:
+      return nil
+    }
+  }
+}
+
+internal protocol Reflection_ServerReflectionServerInterceptorFactoryProtocol: Sendable {
+
+  /// - Returns: Interceptors to use when handling 'serverReflectionInfo'.
+  ///   Defaults to calling `self.makeInterceptors()`.
+  func makeServerReflectionInfoInterceptors() -> [ServerInterceptor<Reflection_ServerReflectionRequest, Reflection_ServerReflectionResponse>]
+}
+
+internal enum Reflection_ServerReflectionServerMetadata {
+  internal static let serviceDescriptor = GRPCServiceDescriptor(
+    name: "ServerReflection",
+    fullName: "reflection.ServerReflection",
+    methods: [
+      Reflection_ServerReflectionServerMetadata.Methods.serverReflectionInfo,
+    ]
+  )
+
+  internal enum Methods {
+    internal static let serverReflectionInfo = GRPCMethodDescriptor(
+      name: "ServerReflectionInfo",
+      path: "/reflection.ServerReflection/ServerReflectionInfo",
+      type: GRPCCallType.bidirectionalStreaming
+    )
+  }
+}