feat: added user gRPC service

Contracts/Proto/user.proto

@@ -0,0 +1,15 @@
+syntax = "proto3";
+option csharp_namespace = "JOBot.Proto";
+
+service User {
+	rpc Register (RegisterRequest) returns (RegisterResponse);
+}
+
+message RegisterRequest{
+	int64 user_id = 1;
+	string username = 2;
+}
+
+message RegisterResponse{
+	int64 user_id = 1;
+}

JOBot.Backend/JOBot.Backend.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk.Web">
+<Project Sdk="Microsoft.NET.Sdk.Web">
 
 	<PropertyGroup>
 		<TargetFramework>net9.0</TargetFramework>
@@ -15,4 +15,8 @@
 		</PackageReference>
 	</ItemGroup>
 
+	<ItemGroup>
+		<Protobuf Include="..\Contracts\Proto\*" GrpcServices="Server"></Protobuf>
+	</ItemGroup>
+
 </Project>

JOBot.Backend/Program.cs

@@ -1,6 +1,9 @@
 var builder = WebApplication.CreateBuilder(args);
+
+builder.Services.AddGrpc();
+
 var app = builder.Build();
 
-app.MapGet("/", () => "Hello World!");
+app.MapGrpcService<UserService>();
 
 app.Run();

JOBot.Backend/Services/gRPC/UserService.cs

@@ -0,0 +1,16 @@
+using Grpc.Core;
+using JOBot.Proto;
+
+class UserService : User.UserBase
+{
+    public override Task<RegisterResponse> Register(
+        RegisterRequest request,
+        ServerCallContext context)
+
+    {
+        return Task.FromResult(new RegisterResponse
+        {
+            UserId = request.UserId
+        });
+    }
+}