Grpc: Fix parsing null value for google.protobuf.Timestamp (#1293)

* Add another example for Grpc client + mapping

* <PackageReference Include="ProtoBufJsonConverter" Version="0.9.0" />

examples/WireMock.Net.Console.GrpcClient/Program.cs

@@ -2,22 +2,42 @@
 
 using Greet;
 using Grpc.Net.Client;
+using Policy2;
 
-namespace WireMock.Net.Console.GrpcClient;
+await TestPolicyAsync();
+// await TestGreeterAsync();
+return;
 
-internal class Program
+async Task TestGreeterAsync()
 {
-    static async Task Main(string[] args)
+    var channel = GrpcChannel.ForAddress("http://localhost:9093/grpc3", new GrpcChannelOptions
     {
-        var channel = GrpcChannel.ForAddress("http://localhost:9093/grpc3", new GrpcChannelOptions
+        Credentials = Grpc.Core.ChannelCredentials.Insecure
+    });
+
+    var client = new Greeter.GreeterClient(channel);
+
+    var reply = await client.SayHelloAsync(new HelloRequest { Name = "stef" });
+
+    Console.WriteLine("Greeting: " + reply.Message);
+}
+
+async Task TestPolicyAsync()
+{
+    var channel = GrpcChannel.ForAddress("http://localhost:9093/grpc-policy", new GrpcChannelOptions
+    {
+        Credentials = Grpc.Core.ChannelCredentials.Insecure
+    });
+
+    var client = new PolicyService2.PolicyService2Client(channel);
+
+    var reply = await client.GetCancellationDetailAsync(new GetCancellationDetailRequest
+    {
+        Client = new Client
         {
-            Credentials = Grpc.Core.ChannelCredentials.Insecure
-        });
+            CorrelationId = "abc"
+        }
+    });
 
-        var client = new Greeter.GreeterClient(channel);
-
-        var reply = await client.SayHelloAsync(new HelloRequest { Name = "stef" });
-
-        System.Console.WriteLine("Greeting: " + reply.Message);
-    }
+    Console.WriteLine("PolicyService2:reply.CancellationName " + reply.CancellationName);
 }

examples/WireMock.Net.Console.GrpcClient/WireMock.Net.Console.GrpcClient.csproj

@@ -5,6 +5,7 @@
         <TargetFramework>net8.0</TargetFramework>
         <ImplicitUsings>enable</ImplicitUsings>
         <Nullable>enable</Nullable>
+        <LangVersion>latest</LangVersion>
     </PropertyGroup>
 
     <ItemGroup>
@@ -18,6 +19,7 @@
 
     <ItemGroup>
         <Protobuf Include="greet.proto" GrpcServices="Client" />
+        <Protobuf Include="policy.proto" GrpcServices="Client" />
     </ItemGroup>
 
-</Project>
+</Project>

examples/WireMock.Net.Console.GrpcClient/policy.proto

@@ -0,0 +1,64 @@
+
+syntax = "proto3";
+
+import "google/protobuf/timestamp.proto";
+
+// option csharp_namespace = "NarrowIntegrationTest.Lookup";
+
+package Policy2;
+
+service PolicyService2 {	
+	rpc GetCancellationDetail (GetCancellationDetailRequest) returns (GetCancellationDetailResponse);
+}
+
+message GetCancellationDetailRequest {
+	Client Client = 1;
+	LegacyPolicyKey LegacyPolicyKey = 2;
+}
+
+message GetCancellationDetailResponse {
+	ResponseStatus Status = 1;
+	string CancellationCode = 2;
+	string CancellationName = 3;
+	string CancellationDescription = 4;
+	google.protobuf.Timestamp CancellationEffDate = 5;
+	string NonRenewalCode = 6;
+	string NonRenewalName = 7;
+	string NonRenewalDescription = 8;
+	google.protobuf.Timestamp NonRenewalEffDate = 9;
+	google.protobuf.Timestamp LastReinstatementDate = 10;
+}
+
+message LegacyPolicyKey {
+	string Group = 1;
+	int32 UnitNumber = 2;
+	int32 Year = 3;
+	string Suffix = 4;
+}
+
+message ResponseStatus {
+	bool HasErrors = 1;
+	bool HasWarnings = 2;
+	repeated string Errors = 3;
+	repeated string Warnings = 4;
+	string CorrelationId = 5;
+}
+
+message Client {
+	string CorrelationId = 1;
+	enum Clients {
+		Unknown = 0;
+        QMS = 1;
+        BillingCenter = 2;
+        PAS = 3;
+        Payroll = 4;
+        Portal = 5;
+        SFO = 6;
+        QuoteAndBind = 7;
+        LegacyConversion = 8;
+        BindNow = 9;
+		PaymentPortal = 10 ;
+		PricingEngine = 11;
+	}
+	Clients ClientName = 2;
+}