Protobuf 該如何處理不定型別

之前筆記 Protobuf 時間屬性該如何表示？ 紀錄了 C# DateTime 屬性在 Protobuf 的 message 表示方式，當時在找資料時發現 any.proto 特別查了資料看可以應用在什麼地方，就個人理解應該就像是 C# 的 object，筆記一下用法，待日後驗證囉

基本環境說明

  1. macOS Mojave 10.14.3
  2. Grpc 1.19.0
  3. Grpc.Tools 1.19.0
  4. Google.Protobuf 3.7.0
  5. Google.Protobuf.Tools 3.7.0
  6. Bogus 26.0.1
  7. Newtonsoft.Json 12.0.1

  8. 資料夾結構

    -- gRPC.Any
    -- gRPC.Any.sln
    -- proto
        -- message.proto
    -- src
        -- gRPC.Message (netstandard2.0)
        -- gRPC.Client (netcoreapp2.2)
        -- gRPC.Server (netcoreapp2.2)

  9. gRPC.Message projcet

    • 安裝套件

      • gRPC

        • Package Manager

          Install-Package Grpc

        • .NET CLI

          dotnet add package Grpc

    • Google.Protobuf

      • Package Manager

        Install-Package Google.Protobuf

      • .NET CLI

        dotnet add package Google.Protobuf

    • 加入 model

      public class UserModel
{
    public Guid Id { get; set; }
    public string Name { get; set; }
    public int Age { get; set; }
}

  10. gRPC.Client 與 gRPC.Server 皆參考 gRPC.Message

  11. gRPC.Client

    var host = "127.0.0.1";
var port = "9999";


var channel = new Channel($"{host}:{port}", ChannelCredentials.Insecure);

var serviceClient = new gRPCService.gRPCServiceClient(channel);

  12. gRPC.Server 實作 gRPCService 並啟動 gRPC

    • 實作

      public class gRPCServiceImplfor : gRPCService.gRPCServiceBase
{
    public override Task<Response> AddUser(AddUserRequest request, ServerCallContext context)
    {
        return base.AddUser(request, context);
    }

    public override Task<Response> GetUsers(GetUsersRequest request, ServerCallContext context)
    {
        return base.GetUsers(request, context);
    }

    public override Task<Response> DeleteUser(DeleteUserRequest request, ServerCallContext context)
    {
        return base.DeleteUser(request, context);
    }
}

    • 啟動

      static async Task Main(string[] args)
{
    var host = "127.0.0.1";
    var port = 9999;

    var serverInstance = new Grpc.Core.Server
    {
        Ports =
        {
            new ServerPort(host, port, ServerCredentials.Insecure)
        }
    };

    Console.WriteLine($"Demo server listening on host:{host} and port:{port}");

    serverInstance.Services.Add(
        Message.gRPCService.BindService(
            new gRPCServiceImpl()));

    serverInstance.Start();

    Console.ReadKey();

    await serverInstance.ShutdownAsync();
}

方法一：使用 string

  1. message 定義

    syntax = "proto3";

package gRPC.Message;
option csharp_namespace = "gRPC.Message";
    
message AddUserRequest{
    string Name=1;
    int32 Age=2;
}
message GetUsersRequest{
}

message DeleteUserRequest{
    string Name=1;
}

message Response{
    bool IsSuccess=1;
    string ResultMsg=2;
    epeated string ResultMsgs=3;
}


service gRPCService {
    rpc AddUser(AddUserRequest) returns (Response);
    rpc GetUsers(GetUsersRequest) returns (Response);
    rpc DeleteUser(DeleteUserRequest) returns (Response);
}

  2. 實際使用

    • client 端

      static void Main(string[] args)
{
    var host = "127.0.0.1";
    var port = "9999";


    var channel = new Channel($"{host}:{port}", ChannelCredentials.Insecure);

    var serviceClient = new gRPCService.gRPCServiceClient(channel);

    var result = serviceClient.AddUser(new AddUserRequest
    {
        Name = "Yowko",
        Age = 35
    });

    var addResult = JsonConvert.DeserializeObject<UserModel>(result.ResultMsg);
    Console.WriteLine($"Id:{addResult.Id};Name:{addResult.Name};Age:{addResult.Age}");

    var usersResult = serviceClient.GetUsers(new GetUsersRequest());

    var users = usersResult.ResultMsgs.Select(a => JsonConvert.DeserializeObject<UserModel>(a));


    foreach (var user in users)
    {
        Console.WriteLine($"Id:{user.Id};Name:{user.Name};Age:{user.Age}");
    }


    var deleteResult = serviceClient.DeleteUser(new DeleteUserRequest()
    {
        Name = "Yowko"
    });

    var delResult = deleteResult.ResultMsg;
    Console.WriteLine($"Msg:{delResult}");
}

    • server 端

      public class gRPCServiceImpl : gRPCService.gRPCServiceBase
{
    public override Task<Response> AddUser(AddUserRequest request, ServerCallContext context)
    {
        var user = FakeUserRule().Generate();

        user.Age = request.Age;
        user.Name = request.Name;
        var response = new Response
        {
            IsSuccess = true,
            ResultMsg = JsonConvert.SerializeObject(user)
        };

        return Task.FromResult(response);
    }

    public override Task<Response> DeleteUser(DeleteUserRequest request, ServerCallContext context)
    {
        var response = new Response
        {
            IsSuccess = true,
            ResultMsg = "User has deleted !!"
        };

        return Task.FromResult(response);
    }

    public override Task<Response> GetUsers(GetUsersRequest request, ServerCallContext context)
    {
        var response = new Response
        {
            IsSuccess = true
        };
        var users = FakeUserRule().Generate(3);
        response.ResultMsgs.AddRange(users.Select(a => JsonConvert.SerializeObject(a))
        );

        return Task.FromResult(response);
    }

    private static Faker<UserModel> FakeUserRule()
    {
        return new Faker<UserModel>()
            .RuleFor(a => a.Id, b => Guid.NewGuid())
            .RuleFor(a => a.Name, (f, u) => f.Name.FirstName())
            .RuleFor(a => a.Age, f => f.Random.Number(1, 10));
    }
}

方法二：使用 any

  1. message 定義

    any 是 google 額外提供的型別，使用時需要 import

    syntax = "proto3";

package gRPC.Message;
option csharp_namespace = "gRPC.Message";
import "google/protobuf/any.proto";

message AddUserRequest{
    string Name=1;
    int32 Age=2;
}
message GetUsersRequest{
}

message DeleteUserRequest{
    string Name=1;
}

message Response{
    bool IsSuccess=1;
    google.protobuf.Any ResultMsg=2;
    repeated google.protobuf.Any ResultMsgs=3;
}


service gRPCService {
    rpc AddUser(AddUserRequest) returns (Response);
    rpc GetUsers(GetUsersRequest) returns (Response);
    rpc DeleteUser(DeleteUserRequest) returns (Response);
}

  2. 將 UserModel 加上 Serializable

    [Serializable]
public class UserModel
{
    public Guid Id { get; set; }
    public string Name { get; set; }
    public int Age { get; set; }
}

  3. 在 gRPC.Message 中加入 ByteStringUtility

    Any 型別使用 ByteString 來傳遞資料，加入 ByteStringUtility 來處理轉型

    public static class ByteStringUtility
{
    public static byte[] ToByteArray<T>(T obj)
    {
        if(obj == null)
            return null;
        BinaryFormatter bf = new BinaryFormatter();
        using(MemoryStream ms = new MemoryStream())
        {
            bf.Serialize(ms, obj);
            return ms.ToArray();
        }
    }

    public static T FromByteArray<T>(byte[] data)
    {
        if(data == null)
            return default(T);
        BinaryFormatter bf = new BinaryFormatter();
        using(MemoryStream ms = new MemoryStream(data))
        {
            object obj = bf.Deserialize(ms);
            return (T)obj;
        }
    }
}

  4. 編譯需額外引用參考 any.proto

    any.proto 位於 /Users/whoami/.nuget/packages/google.protobuf.tools/3.7.0/tools/google/protobuf/any.proto

    /Users/`whoami`/.nuget/packages/grpc.tools/1.19.0/tools/macosx_x64/protoc -I /Users/`whoami`/.nuget/packages/google.protobuf.tools/3.7.0/tools/ -I proto/  --csharp_out src/gRPC.Message --grpc_out src/gRPC.Message proto/*.proto --plugin=protoc-gen-grpc=/Users/`whoami`/.nuget/packages/grpc.tools/1.19.0/tools/macosx_x64/grpc_csharp_plugin

  5. 實際使用

    • client 端

      var result = serviceClient.AddUser(new AddUserRequest
{
    Name = "Yowko",
    Age = 35
});

var addResult =
    ByteStringUtility.FromByteArray<UserModel>(result.ResultMsg.Value
        .ToByteArray());
Console.WriteLine($"Id:{addResult.Id};Name:{addResult.Name};Age:{addResult.Age}");

var usersResult = serviceClient.GetUsers(new GetUsersRequest());

var users = usersResult.ResultMsgs.Select(a =>
    ByteStringUtility.FromByteArray<UserModel>(a.Value.ToByteArray()));


foreach (var user in users)
{
    Console.WriteLine($"Id:{user.Id};Name:{user.Name};Age:{user.Age}");
}
        

var deleteResult = serviceClient.DeleteUser(new DeleteUserRequest()
{
    Name = "Yowko"
});

var delResult = ByteStringUtility.FromByteArray<string>(deleteResult.ResultMsg.Value
    .ToByteArray());
Console.WriteLine($"Msg:{delResult}");

    • server 端

      public class gRPCServiceImpl : gRPCService.gRPCServiceBase
{
    public override Task<Response> AddUser(AddUserRequest request, ServerCallContext context)
    {
        var user = FakeUserRule().Generate();

        user.Age = request.Age;
        user.Name = request.Name;
        var response = new Response
        {
            IsSuccess = true,
            ResultMsg = new Any
            {
                Value = Google.Protobuf.ByteString.CopyFrom(ByteStringUtility.ToByteArray(user))
            }
        };
                
        return Task.FromResult(response);
    }

    public override Task<Response> DeleteUser(DeleteUserRequest request, ServerCallContext context)
    {
        var response = new Response
        {
            IsSuccess = true,
            ResultMsg = new Any
            {
                Value = Google.Protobuf.ByteString.CopyFrom(ByteStringUtility.ToByteArray("User has deleted !!"))
            }
        };

        return Task.FromResult(response);
    }

    public override Task<Response> GetUsers(GetUsersRequest request, ServerCallContext context)
    {
        var response = new Response
        {
            IsSuccess = true
        };
        var users = FakeUserRule().Generate(3);
        response.ResultMsgs.AddRange(users.Select(a => new Any()
        {
            Value = Google.Protobuf.ByteString.CopyFrom(ByteStringUtility.ToByteArray(a))
        }));

        return Task.FromResult(response);
    }

    private static Faker<UserModel> FakeUserRule()
    {
        return new Faker<UserModel>()
            .RuleFor(a => a.Id, b => Guid.NewGuid())
            .RuleFor(a => a.Name, (f, u) => f.Name.FirstName())
            .RuleFor(a => a.Age, f => f.Random.Number(1, 10));
    }
}

心得

以結果來看 string 省事不少，但直覺上應該是 any 效率比較好，不過口說無憑，改天有時間再來效能評測一下

回到 any 的使用情境，原本想試試可不可以達成 C# Generic 用途，但看來應該就是 object 而已，不過也是試過才知道，至少知道哪些可以做到哪些不行

程式碼可以參考 yowko/gRPC-Any-CSharp-Sample

參考資訊

  1. gRPC development on .NET Core - Basic
  2. How to convert byte array to any type
  3. yowko/gRPC-Any-CSharp-Sample