# MagicOnion_1

**Repository Path**: avadars_admin/MagicOnion_1

## Basic Information

- **Project Name**: MagicOnion_1
- **Description**: MagicOnion Unified Realtime/API Engine for .NET Core and Unity. 
原仓库地址：https://github.com/Cysharp/MagicOnion.git

- **Primary Language**: C#
- **License**: MIT
- **Default Branch**: main
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 1
- **Created**: 2023-08-22
- **Last Updated**: 2023-08-22

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# MagicOnion
![build-debug](https://github.com/Cysharp/MagicOnion/workflows/build-debug/badge.svg) ![build-canary](https://github.com/Cysharp/MagicOnion/workflows/build-canary/badge.svg) ![build-release](https://github.com/Cysharp/MagicOnion/workflows/build-release/badge.svg) [![Releases](https://img.shields.io/github/release/Cysharp/MagicOnion.svg)](https://github.com/Cysharp/MagicOnion/releases)

Unified Realtime/API framework for .NET platform and Unity.

[📖 Table of contents](#-table-of-contents)

## About MagicOnion
MagicOnion is a modern RPC framework for .NET platform that provides bi-directional real-time communications such as [SignalR](https://github.com/aspnet/AspNetCore/tree/master/src/SignalR) and [Socket.io](https://socket.io/) and RPC mechanisms such as WCF and web-based APIs.

This framework is based on [gRPC](https://grpc.io/), which is a fast and compact binary network transport for HTTP/2. However, unlike plain gRPC, it treats C# interfaces as a protocol schema, enabling seamless code sharing between C# projects without `.proto` (Protocol Buffers IDL).

![image](https://user-images.githubusercontent.com/46207/50965239-c4fdb000-1514-11e9-8365-304c776ffd77.png)

> Interfaces are schemas and provide API services, just like the plain C# code

![image](https://user-images.githubusercontent.com/46207/50965825-7bae6000-1516-11e9-9501-dc91582f4d1b.png)

> Using the StreamingHub real-time communication service, the server can broadcast data to multiple clients

MagicOnion can be adopted or replaced in the following use cases:

- RPC services such as gRPC, used by Microservices, and WCF, commonly used by WinForms/WPF
- API services such as ASP.NET Core MVC targeting Unity, Xamarin, and Windows clients
- Bi-directional real-time communication such as Socket.io, SignalR, Photon and UNet

MagicOnion uses [MessagePack for C#](https://github.com/neuecc/MessagePack-CSharp) to serialize call arguments and return values. NET primitives and other complex types that can be serialized into MessagePack objects. See MessagePack for C# for details about serialization.

## Requirements
MagicOnion server requires NET Core 3.1 or .NET 5.0+.

MagicOnion client supports a wide range of platforms, including .NET Framework 4.6.1 to .NET 5.0 as well as Unity.

- Server-side (MagicOnion.Server)
    - .NET 6.0+
- Client-side (MagicOnion.Client)
    - .NET Standard 2.1 (.NET Core 3.x+, .NET 5.0+, Xamarin)
    - .NET Standard 2.0 (.NET Framework 4.6.1+, Universal Windows Platform, .NET Core 2.x)
    - Unity 2020.3 (LTS) or newer

## Quick Start
### Server-side project
#### Setup a project for MagicOnion
Start from minimal API(details: [Tutorial: Create a minimal web API with ASP.NET Core](https://learn.microsoft.com/en-us/aspnet/core/tutorials/min-web-api)) so create **ASP.NET Core Empty** template and Add NuGet package `Grpc.AspNetCore` and `MagicOnion.Server` to your project. If you are using the .NET CLI tools to add it, you can run the following command.

```bash
dotnet add package Grpc.AspNetCore
dotnet add package MagicOnion.Server
```

Open `Program.cs` and add some configuration to Services and App.

```csharp
using MagicOnion;
using MagicOnion.Server;

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddGrpc();       // Add this line(Grpc.AspNetCore)
builder.Services.AddMagicOnion(); // Add this line(MagicOnion.Server)

var app = builder.Build();

app.MapMagicOnionService(); // Add this line

app.Run();
```

Now you are ready to use MagicOnion on your server project.

#### Implements a service on MagicOnion
MagicOnion provides a Web API-like RPC service and a StreamingHub for real-time communication. This section implements a Web API-like RPC service.

Add an `IMyFirstService` interface to be shared between the server and the client (namespace should match the project).

```csharp
using System;
using MagicOnion;

namespace MyApp.Shared
{
    // Defines .NET interface as a Server/Client IDL.
    // The interface is shared between server and client.
    public interface IMyFirstService : IService<IMyFirstService>
    {
        // The return type must be `UnaryResult<T>` or `UnaryResult`.
        UnaryResult<int> SumAsync(int x, int y);
    }
}
```

Add a class that implements the interface `IMyFirstService`. The client calls this class.

```csharp
using System;
using MagicOnion;
using MagicOnion.Server;
using MyApp.Shared;

namespace MyApp.Services
{
    // Implements RPC service in the server project.
    // The implementation class must inherit `ServiceBase<IMyFirstService>` and `IMyFirstService`
    public class MyFirstService : ServiceBase<IMyFirstService>, IMyFirstService
    {
        // `UnaryResult<T>` allows the method to be treated as `async` method.
        public async UnaryResult<int> SumAsync(int x, int y)
        {
            Console.WriteLine($"Received:{x}, {y}");
            return x + y;
        }
    }
}
```

The service is now defined and implemented. That's it.

Now you can start MagicOnion server as you would a ASP.NET Core project using the F5 key or the `dotnet run` command.

### Client-side: Call the service on MagicOnion

> **NOTE:** If you want to use MagicOnion client with Unity clients, see also [Support for Unity client](#support-for-unity-client) section.

Create a **Console application** project and add NuGet package `MagicOnion.Client` to the project.

Share `IMyFirstService` interface with the client. Share the interface definition in some way, such as file links, shared libraries, or copy and paste.

In the client code, Create `MagicOnionClient` client proxy on the shared interface and calls the service transparently.

```csharp
using Grpc.Net.Client;
using MagicOnion.Client;
using MyApp.Shared;

// Connect to the server using gRPC channel.
var channel = GrpcChannel.ForAddress("https://localhost:5001");

// NOTE: If your project targets non-.NET Standard 2.1, use `Grpc.Core.Channel` class instead.
// var channel = new Channel("localhost", 5001, new SslCredentials());

// Create a proxy to call the server transparently.
var client = MagicOnionClient.Create<IMyFirstService>(channel);

// Call the server-side method using the proxy.
var result = await client.SumAsync(123, 456);
Console.WriteLine($"Result: {result}");
```

## Installation
MagicOnion is available in four NuGet packages. Please install any of the packages as needed.

> **NOTE:** If you want to use MagicOnion client with Unity clients, see also [Support for Unity client](#support-for-unity-client) section.

The package `MagicOnion.Server` to implement the server. You need to install this package to implement services on your server.

```bash
dotnet add package MagicOnion.Server
```

The package `MagicOnion.Client` to implement the client. To implement the client such as as WPF and Xamarin, you need to install this package.

```bash
dotnet add package MagicOnion.Client
```

The package `MagicOnion.Abstractions` provides interfaces and attributes commonly used by servers and clients. To create a class library project which is shared between the servers and the clients, you need to install this package.

```bash
dotnet add package MagicOnion.Abstractions
```

The package `MagicOnion` is meta package to implements the role of both server and client.
To implement server-to-server communication such as Microservices, that can be both a server and a client, we recommend to install this package.

```bash
dotnet add package MagicOnion
```

## 📖 Table of contents

- [About MagicOnion](#about-magiconion)
- [Quick Start](#quick-start)
- [Installation](#installation)
- Fundamentals
    - [Service](#service)
    - [StreamingHub](#streaminghub)
    - [Filter](#filter)
    - [ClientFilter](#clientfilter)
    - [ServiceContext and Lifecycle](#servicecontext-and-lifecycle)
    - [ExceptionHandling and StatusCode](#exceptionhandling-and-statuscode)
    - [Group and GroupConfiguration](#group-and-groupconfiguration)
    - [Dependency Injection](#dependency-injection)
    - [Project Structure](#project-structure)
- Client
    - [Support for Unity client](#support-for-unity-client)
        - [iOS build with gRPC](#ios-build-with-grpc)
        - [Stripping debug symbols from ios/libgrpc.a](#stripping-debug-symbols-from-ioslibgrpca)
        - [Stripping debug symbols from libgrpc_csharp_ext.so](#stripping-debug-symbols-from-libgrpccsharpextso)
        - [Workaround for il2cpp + Windows Build failure](#workaround-for-il2cpp--windows-build-failure)
    - [gRPC Keepalive](#grpc-keepalive)
- [HTTPS (TLS)](#https-tls)
- [Deployment](#deployment)
- Integrations
    - [Swagger](#swagger)
- Advanced
    - [MagicOnionOption/Logging](#magiconionoptionlogging)
    - [Raw gRPC APIs](#raw-grpc-apis)
    - [Zero deserialization mapping](#zero-deserialization-mapping)
- Experimentals
    - [OpenTelemetry](#opentelemetry)
- [License](#license)

## Fundamentals
### Service
A service is a mechanism that provides a request/response API in the style of RPC or Web-API, and is implemented as a Unary call to gRPC.
A service can be defined as a C# interface to benefit from the type. This means that it can be observed as a request over HTTP/2.

#### Service definition (Shared library)
```csharp
using System;
using MagicOnion;

namespace MyApp.Shared
{
    // Defines .NET interface as a Server/Client IDL.
    // The interface is shared between server and client.
    public interface IMyFirstService : IService<IMyFirstService>
    {
        // The return type must be `UnaryResult<T>` or `UnaryResult`.
        UnaryResult<int> SumAsync(int x, int y);
        // `UnaryResult` does not have a return value like `Task`, `ValueTask`, or `void`.
        UnaryResult DoWorkAsync();
    }
}
```

#### Service implementation (Server-side)
```csharp
using System;
using MagicOnion;
using MagicOnion.Server;
using MyApp.Shared;

namespace MyApp.Services
{
    // Implements RPC service in the server project.
    // The implementation class must inherit `ServiceBase<IMyFirstService>` and `IMyFirstService`
    public class MyFirstService : ServiceBase<IMyFirstService>, IMyFirstService
    {
        // `UnaryResult<T>` allows the method to be treated as `async` method.
        public async UnaryResult<int> SumAsync(int x, int y)
        {
            Console.WriteLine($"Received:{x}, {y}");
            return x + y;
        }

        public async UnaryResult DoWorkAsync()
        {
            // Something to do ...
        }
    }
}
```

In MagicOnion, unlike gRPC in general, the body of the request is serialized by MessagePack for sending and receiving.


### StreamingHub
StreamingHub is a fully-typed realtime server <--> client communication framework.

This sample is for Unity(use Vector3, GameObject, etc) but StreamingHub supports .NET Core, too.

```csharp
// Server -> Client definition
public interface IGamingHubReceiver
{
    // The method must have a return type of `void` and can have up to 15 parameters of any type.
    void OnJoin(Player player);
    void OnLeave(Player player);
    void OnMove(Player player);
}

// Client -> Server definition
// implements `IStreamingHub<TSelf, TReceiver>`  and share this type between server and client.
public interface IGamingHub : IStreamingHub<IGamingHub, IGamingHubReceiver>
{
    // The method must return `ValueTask`, `ValueTask<T>`, `Task` or `Task<T>` and can have up to 15 parameters of any type.
    ValueTask<Player[]> JoinAsync(string roomName, string userName, Vector3 position, Quaternion rotation);
    ValueTask LeaveAsync();
    ValueTask MoveAsync(Vector3 position, Quaternion rotation);
}

// for example, request object by MessagePack.
[MessagePackObject]
public class Player
{
    [Key(0)]
    public string Name { get; set; }
    [Key(1)]
    public Vector3 Position { get; set; }
    [Key(2)]
    public Quaternion Rotation { get; set; }
}
```

```csharp
// Server implementation
// implements : StreamingHubBase<THub, TReceiver>, THub
public class GamingHub : StreamingHubBase<IGamingHub, IGamingHubReceiver>, IGamingHub
{
    // this class is instantiated per connected so fields are cache area of connection.
    IGroup room;
    Player self;
    IInMemoryStorage<Player> storage;

    public async ValueTask<Player[]> JoinAsync(string roomName, string userName, Vector3 position, Quaternion rotation)
    {
        self = new Player() { Name = userName, Position = position, Rotation = rotation };

        // Group can bundle many connections and it has inmemory-storage so add any type per group.
        (room, storage) = await Group.AddAsync(roomName, self);

        // Typed Server->Client broadcast.
        Broadcast(room).OnJoin(self);

        return storage.AllValues.ToArray();
    }

    public async ValueTask LeaveAsync()
    {
        await room.RemoveAsync(this.Context);
        Broadcast(room).OnLeave(self);
    }

    public async ValueTask MoveAsync(Vector3 position, Quaternion rotation)
    {
        self.Position = position;
        self.Rotation = rotation;
        Broadcast(room).OnMove(self);
    }

    // You can hook OnConnecting/OnDisconnected by override.
    protected override ValueTask OnDisconnected()
    {
        // on disconnecting, if automatically removed this connection from group.
        return ValueTask.CompletedTask;
    }
}
```

You can write client like this.

```csharp
public class GamingHubClient : IGamingHubReceiver
{
    Dictionary<string, GameObject> players = new Dictionary<string, GameObject>();

    IGamingHub client;

    public async ValueTask<GameObject> ConnectAsync(ChannelBase grpcChannel, string roomName, string playerName)
    {
        this.client = await StreamingHubClient.ConnectAsync<IGamingHub, IGamingHubReceiver>(grpcChannel, this);

        var roomPlayers = await client.JoinAsync(roomName, playerName, Vector3.zero, Quaternion.identity);
        foreach (var player in roomPlayers)
        {
            (this as IGamingHubReceiver).OnJoin(player);
        }

        return players[playerName];
    }

    // methods send to server.

    public ValueTask LeaveAsync()
    {
        return client.LeaveAsync();
    }

    public ValueTask MoveAsync(Vector3 position, Quaternion rotation)
    {
        return client.MoveAsync(position, rotation);
    }

    // dispose client-connection before channel.ShutDownAsync is important!
    public Task DisposeAsync()
    {
        return client.DisposeAsync();
    }

    // You can watch connection state, use this for retry etc.
    public Task WaitForDisconnect()
    {
        return client.WaitForDisconnect();
    }

    // Receivers of message from server.

    void IGamingHubReceiver.OnJoin(Player player)
    {
        Debug.Log("Join Player:" + player.Name);

        var cube = GameObject.CreatePrimitive(PrimitiveType.Cube);
        cube.name = player.Name;
        cube.transform.SetPositionAndRotation(player.Position, player.Rotation);
        players[player.Name] = cube;
    }

    void IGamingHubReceiver.OnLeave(Player player)
    {
        Debug.Log("Leave Player:" + player.Name);

        if (players.TryGetValue(player.Name, out var cube))
        {
            GameObject.Destroy(cube);
        }
    }

    void IGamingHubReceiver.OnMove(Player player)
    {
        Debug.Log("Move Player:" + player.Name);

        if (players.TryGetValue(player.Name, out var cube))
        {
            cube.transform.SetPositionAndRotation(player.Position, player.Rotation);
        }
    }
}
```

### Filter
MagicOnion filter is powerful feature to hook before-after invoke. It is useful than gRPC server interceptor.

![image](https://user-images.githubusercontent.com/46207/50969421-cb465900-1521-11e9-8824-8a34cc52bbe4.png)

```csharp
// You can attach per class/method like [SampleFilter]
// for StreamingHub methods, implement StreamingHubFilterAttribute instead.
public class SampleFilterAttribute : MagicOnionFilterAttribute
{
    public override async ValueTask Invoke(ServiceContext context, Func<ServiceContext, ValueTask> next)
    {
        try
        {
            /* on before */
            await next(context); // next
            /* on after */
        }
        catch
        {
            /* on exception */
            throw;
        }
        finally
        {
            /* on finally */
        }
    }
}
```

Here is example of what kind of filter can be stacked.

![image](https://user-images.githubusercontent.com/46207/50969539-2bd59600-1522-11e9-84ab-15dd85e3dcac.png)

MagicOnion also provides an API for filters that is very similar to filter on ASP.NET Core MVC.
These APIs support flexible filter implementations.

- `IMagicOnionServiceFilter` interface
- `IStreamingHubFilter` interface
- `IMagicOnionFilterFactory<T>` interface
- `IMagicOnionOrderedFilter` interface

#### Ordering
Filters can be ordered and they are executed in the following order:

```
[Ordered Filters] -> [Global Filters] -> [Class Filters] -> [Method Filters]
```

Unordered filters are treated as last (`int.MaxValue`) and executed in the order in which they are added.

#### GlobalFilters
Filters that apply to the application globally can be added at `GlobalFilters` of `MagicOnionOptions`.

```csharp
services.AddMagicOnion(options =>
{
    options.GlobalFilters.Add<MyServiceFilter>();
    options.GlobalStreamingHubFilters.Add<MyHubFilter>();
});
```

#### Dependency Injections
MagicOnion filters supports [Dependency Injection](#dependency-injection). There are two ways to activate a filter by using `FromTypeFilter`, `FromServiceFitler` or by using `IMagicOnionFilterFactory`.

The following is an example of how to use `FromTypeFilter`, `FromServiceFitler`.

```csharp
public class MyServiceFilterAttribute : MagicOnionFilterAttribute
{
    private readonly ILogger _logger;

    // the `logger` parameter will be injected at instantiating.
    public MyServiceFilterAttribute(ILogger<MyServiceFilterAttribute> logger)
    {
        _logger = logger;
    }

    public override async ValueTask Invoke(ServiceContext context, Func<ServiceContext, ValueTask> next)
    {
        _logger.LogInformation($"MyServiceFilter Begin: {context.Path}");
        await next(context);
        _logger.LogInformation($"MyServiceFilter End: {context.Path}");
    }
}
```

Register filters using attributes with constructor injection(you can use `[FromTypeFilter]` and `[FromServiceFilter]`).

```csharp
[FromTypeFilter(typeof(MyFilterAttribute))]
public class MyService : ServiceBase<IMyService>, IMyService
{
    // The filter will instantiate from type.
    [FromTypeFilter(typeof(MySecondFilterAttribute))]
    public UnaryResult<int> Foo()
    {
        return UnaryResult(0);
    }

    // The filter will instantiate from type with some arguments. if the arguments are missing, it will be obtained from `IServiceProvider`
    [FromTypeFilter(typeof(MyThirdFilterAttribute), Arguments = new object[] { "foo", 987654 })]
    public UnaryResult<int> Bar()
    {
        return UnaryResult(0);
    }

    // The filter instance will be provided via `IServiceProvider`.
    [FromServiceFilter(typeof(MyFourthFilterAttribute))]
    public UnaryResult<int> Baz()
    {
        return UnaryResult(0);
    }
}
```

The following is an example of how to use `IMagicOnionFilterFactory<T>`.

This is a clean way of writing when using DI while still having parameters for the attributes.

```csharp
public class MyServiceFilterAttribute : Attribute, IMagicOnionFilterFactory<IMagicOnionServiceFilter>, IMagicOnionOrderedFilter
{
    readonly string label;

    public int Order { get; set; } = int.MaxValue;

    public MyServiceFilterAttribute(string label)
    {
        this.label = label;
    }

    public IMagicOnionServiceFilter CreateInstance(IServiceProvider serviceProvider)
        => new MyServiceFilter(serviceProvider.GetRequiredService<ILogger<MyServiceFilterAttribute>>());

    class MyServiceFilter : IMagicOnionServiceFilter
    {
        readonly string label;
        readonly ILogger logger;

        public MyServiceFilter(string label, ILogger<MyServiceFilterAttribute> logger)
        {
            this.label = label;
            this.logger = logger;
        }

        public async ValueTask Invoke(ServiceContext context, Func<ServiceContext, ValueTask> next)
        {
            logger.LogInformation($"[{label}] MyServiceFilter Begin: {context.Path}");
            await next(context);
            logger.LogInformation($"[{label}] MyServiceFilter End: {context.Path}");
        }
    }
}
```
```csharp
[MyServiceFilter("Class")]
public class MyService : ServiceBase<IMyService>, IMyService
{
    [MyServiceFilter("Method")]
    public UnaryResult<int> Foo()
    {
        return UnaryResult(0);
    }
}
```

#### Extension Interfaces
The following interfaces are provided for filter extensions. These interfaces are similar to ASP.NET Core MVC filter mechanism.

- `IMagicOnionFilterFactory<T>`
- `IMagicOnionOrderedFilter`
- `IMagicOnionServiceFilter`
- `IStreamingHubFilter`

`MagicOnionFilterAttributes` and `StreamingHubFilterAttribute` implement these interfaces for easy use. You can use these interfaces for more flexible implementation.


### ClientFilter
MagicOnion client-filter is a powerful feature to hook before-after invoke. It is useful than gRPC client interceptor.

> Currently only supports on Unary.

```csharp
// you can attach in MagicOnionClient.Create.
var client = MagicOnionClient.Create<ICalcService>(channel, new IClientFilter[]
{
    new LoggingFilter(),
    new AppendHeaderFilter(),
    new RetryFilter()
});
```

You can create custom client-filter by implements `IClientFilter.SendAsync`.

```csharp
public class IDemoFilter : IClientFilter
{
    public async ValueTask<ResponseContext> SendAsync(RequestContext context, Func<RequestContext, ValueTask<ResponseContext>> next)
    {
        try
        {
            /* Before Request, context.MethodPath/CallOptions/Items, etc */

            var response = await next(context); /* Call next filter or method body */

            /* After Request, response.GetStatus/GetTrailers/GetResponseAs<T>, etc */

            return response;
        }
        catch (RpcException ex)
        {
            /* Get gRPC Error Response */
            throw;
        }
        catch (OperationCanceledException ex)
        {
            /* If canceled */
            throw;
        }
        catch (Exception ex)
        {
            /* Other Exception */
            throw;
        }
        finally
        {
            /* Common Finalize */
        }
    }
}
```

Here is the sample filters, you can imagine what you can do.

```csharp
public class AppendHeaderFilter : IClientFilter
{
    public async ValueTask<ResponseContext> SendAsync(RequestContext context, Func<RequestContext, ValueTask<ResponseContext>> next)
    {
        // add the common header(like authentication).
        var header = context.CallOptions.Headers;
        if (!header.Any(x => x.Key == "x-foo"))
        {
            header.Add("x-foo", "abcdefg");
            header.Add("x-bar", "hijklmn");
        }

        return await next(context);
    }
}

public class LoggingFilter : IClientFilter
{
    public async ValueTask<ResponseContext> SendAsync(RequestContext context, Func<RequestContext, ValueTask<ResponseContext>> next)
    {
        Console.WriteLine("Request Begin:" + context.MethodPath); // Debug.Log in Unity.

        var sw = Stopwatch.StartNew();
        var response = await next(context);
        sw.Stop();

        Console.WriteLine("Request Completed:" + context.MethodPath + ", Elapsed:" + sw.Elapsed.TotalMilliseconds + "ms");

        return response;
    }
}

public class ResponseHandlingFilter : IClientFilter
{
    public async ValueTask<ResponseContext> SendAsync(RequestContext context, Func<RequestContext, ValueTask<ResponseContext>> next)
    {
        var response = await next(context);

        if (context.MethodPath == "ICalc/Sum")
        {
            // You can cast response type.
            var sumResult = await response.GetResponseAs<int>();
            Console.WriteLine("Called Sum, Result:" + sumResult);
        }

        return response;
    }
}

public class MockRequestFilter : IClientFilter
{
    public async ValueTask<ResponseContext> SendAsync(RequestContext context, Func<RequestContext, ValueTask<ResponseContext>> next)
    {
        if (context.MethodPath == "ICalc/Sum")
        {
            // don't call next, return mock result.
            return new ResponseContext<int>(9999);
        }

        return await next(context);
    }
}

public class RetryFilter : IClientFilter
{
    public async ValueTask<ResponseContext> SendAsync(RequestContext context, Func<RequestContext, ValueTask<ResponseContext>> next)
    {
        Exception lastException = null;
        var retryCount = 0;
        while (retryCount != 3)
        {
            try
            {
                // using same CallOptions so be careful to add duplicate headers or etc.
                return await next(context);
            }
            catch (Exception ex)
            {
                lastException = ex;
            }
            retryCount++;
        }

        throw new Exception("Retry failed", lastException);
    }
}

public class EncryptFilter : IClientFilter
{
    public async ValueTask<ResponseContext> SendAsync(RequestContext context, Func<RequestContext, ValueTask<ResponseContext>> next)
    {
        context.SetRequestMutator(bytes => Encrypt(bytes));
        context.SetResponseMutator(bytes => Decrypt(bytes));

        return await next(context);
    }
}
```

### ServiceContext and Lifecycle
Service/StreamingHub's method or `MagicOnionFilter` can access `this.Context` it is

| Property | Description |
| --- | --- |
| `ConcurrentDictionary<string, object>` Items | Object storage per request/connection. |
| `Guid` ContextId | Unique ID per request(Service)/connection(StreamingHub). |
| `DateTime` Timestamp | Timestamp that request/connection is started time. |
| `Type` ServiceType | Invoked Class. |
| `MethodInfo` MethodInfo | Invoked Method. |
| `ILookup<Type, Attribute> AttributeLookup | Cached Attributes that merged both service and method. |
| `ServerCallContext` CallContext | Raw gRPC Context. |
| `MessagePackSerializerOptions` SerializerOptions | Using MessagePack serializer options. |
| `IServiceProvider` ServiceProvider | Get the service provider. |

`Items` is useful, for example authentication filter add UserId to Items and take out from service method.

> If using StreamingHub, ServiceContext means per connected context so `Items` is not per method invoke. `StreamingHubContext.Items` supports per streaming hub method request but currently can not take from streaming hub method(only use in StreamingHubFilter). [Issue:#67](https://github.com/Cysharp/MagicOnion/issues/67), it will fix.

MagicOnion supports get current context globally like HttpContext.Current. `ServiceContext.Current` can get it but it requires `MagicOnionOptions.EnableCurrentContext = true`, default is false.

Lifecycle image of ServiceBase

```
gRPC In(
    var context = new ServiceContext();
    Filter.Invoke(context,
        var service = new ServiceImpl();
        service.ServiceContext = context;
        service.MethodInvoke(
            /* method impl */
        )
    )
)
```

Lifecycle image of StreamingHub(StreamingHub is inherited from ServiceBase)

```
gRPC In(
    var context = new ServiceContext();
    Filter.Invoke(context,
        var hub = new StreamingHubImpl();
        hub.ServiceContext = context;
        hub.Connect(
            while (connecting) {
                Streaming In(
                    var streamingHubContext = new StreamingHubContext(context);
                    StreamingHubFilter.Invoke(streamingHubContext,
                        hub.MethodInvoke(
                            /* method impl */
                        )
                    )
                )
            }
        )
    )
)
```

StreamingHub instance is shared while connecting so StreamingHub's field can use cache area of connection.

### ExceptionHandling and StatusCode
If you are return custom status code from server to client, you can use `throw new ReturnStatusException`.

```csharp
public Task SendMessageAsync(string message)
{
    if (message.Contains("foo"))
    {
        //
        throw new ReturnStatusException((Grpc.Core.StatusCode)99, "invalid");
    }

    // ....
```

Client can receive exception as gRPC's `RpcException`. If performance centric to avoid exception throw, you can use raw gRPC CallContext.Status(`ServiceContext.CallContext.Status`) and set status directly.

MagicOnion's engine catched exception(except ReturnStatusException), set `StatusCode.Unknown` and client received gRPC's `RpcException`. If `MagicOnionOption.IsReturnExceptionStackTraceInErrorDetail` is true, client can receive StackTrace of server exception, it is very useful for debugging but has critical issue about security so should only to enable debug build.

### Group and GroupConfiguration
StreamingHub's broadcast system is called Group. It can get from StreamingHub impl method, `this.Group`(this.Group type is `HubGroupRepository`, not `IGroup`).

Current connection can add to group by `this.Group.AddAsync(string groupName)`, return value(`IGroup`) is joined group broadcaster so cache to field. It is enable per connection(if disconnected, automatically leaved from group). If you want to use some restriction, you can use `TryAddAsync(string groupName, int incluciveLimitCount, bool createIfEmpty)`.

`IGroup` can pass to StreamingHub.`Broadcast`, `BroadcastExceptSelf`, `BroadcastExcept` and calls client proxy.

```csharp
public class ChatHub : StreamingHubBase<IChatHub, IMessageReceiver>, IChatHub
{
    string userName;
    IGroup room;

    public async ValueTask JoinAsync(string userName, string roomName)
    {
        this.userName = userName;
        this.room = await Group.AddAsync(roomName);
    }

    public async ValueTask SendMessageAsync(string message)
    {
        Broadcast(room).OnReceiveMessage(userName, message);
    }
}
```

> GroupRepository is created per StreamingHub type

> If you want to create ServerSide loop and broadcast out of StreamingHub, you can pass Broadcast(room) result but it is unnatural, I'll add support kit of create server-side loop

Group has in-memory storage, it can store extra data to group member. It can set `Group.AddAsync(string groupName, TStorage data)` instead of standard AddAsync.

Data is can get from `group.GetInMemoryStorage<T>` and can invoke `AllValues`, `Set(Guid connectionId, T Value)`, `Get(Guid connectionId)`.

> StreamingHub's ConnectionId is ServiceContext.ContextId

Default MagicOnion's group is inmemory and using `ImmutableArrayGroup`. This group implementation is tuned for small room, not enter/leave frequently. If large room and enter/leave frequently design, you can use `ConcurrentDictionaryGroup`. It can configure by `GroupConfigurationAttribute` or `MagicOnionOptions.DefaultGroupRepositoryFactory`.

```csharp
// use ***GroupRepositoryFactory type.
[GroupConfiguration(typeof(ConcurrentDictionaryGroupRepositoryFactory))]
public class ChatHub : StreamingHubBase<IChatHub, IMessageReceiver>, IChatHub
{
    // ...
}
```

MagicOnion has distribute system called redis-backplane for group broadcast.

![image](https://user-images.githubusercontent.com/46207/50974777-5f6aed00-152f-11e9-97f3-ba2a0c97f0eb.png)

```bash
dotnet add package MagicOnion.Server.Redis
```

```csharp
services.AddMagicOnion()
    .UseRedisGroupRepository(options =>
    {
        options.ConnectionMultiplexer = ConnectionMultiplexer.Connect("localhost:6379");
    });
    // If you want to use Redis backplane by default, you can specify `registerAsDefault: true`.
```
```csharp
// Use Redis as backplane
[GroupConfiguration(typeof(RedisGroupRepositoryFactory))]
public class ...
{
}
```

### Dependency Injection
Like Dependency Injection on ASP.NET Core MVC, MagicOnion also supports DI to services and hubs.

```csharp
public class MyFirstService : ServiceBase<IMyFirstService>, IMyFirstService
{
    IOptions<MyConfig> config;
    ILogger<MyFirstService> logger;

    public MyFirstService(IOptions<MyConfig> config, ILogger<MyFirstService> logger)
    {
        this.config = config;
        this.logger = logger;
    }

    // ...
}
```


### Project Structure
If creates Server-Client project, I recommend make three projects. `Server`, `ServerDefinition`, `Client`.

![image](https://cloud.githubusercontent.com/assets/46207/21081857/e0f6dfce-c012-11e6-850d-358c5b928a82.png)

ServerDefinition is only defined interface(`IService<>`, `IStreamingHub<,>`)(and some share request/response types).

If debugging, We recommend use [SwitchStartupProject](https://marketplace.visualstudio.com/items?itemName=vs-publisher-141975.SwitchStartupProjectforVS2017) extension of VisualStudio and launch both Server and Client.

```json
"MultiProjectConfigurations": {
    "Server + Client": {
        "Projects": {
            "FooService": {},
            "FooClient": {}
        }
    }
}
```

It can step-in/out seamlessly in server and client.

for Unity, you can't share by DLL(because can't share `IServer<>` because it is different reference both Unity and Server). It is slightly complex so we provides sample project and explanation.

see: [samples](https://github.com/Cysharp/MagicOnion/tree/master/samples) page and ReadMe.



# Clients

## Support for Unity client
MagicOnion supports from Unity version 2018.4.13f1 and above, which is available for `.NET 4.x` runtime and C# 7.3 or latest.

Using MagicOnion with Unity client requires the following four things:

- MagicOnion.Client.Unity.package (Unity asset package for MagicOnion library)
- gRPC library for Unity client (gRPC official)
- MessagePack for C#
- MagicOnion code generator (for IL2CPP)

### MagicOnion.Client.Unity.package (Unity asset package for MagicOnion library)
`MagicOnion.Client.Unity.package` is available for download from [Releases](https://github.com/cysharp/MagicOnion/releases) page of this repository.

The package contains the code to use MagicOnion with Unity. It consists of several extensions for Unity in addition to MagicOnion.Client NuGet package.

### gRPC library for Unity client (gRPC official)
gRPC library is not included in MagicOnion package. You need to download and install separately.

gRPC library can be found at [gRPC daily builds](https://packages.grpc.io/), click `Build ID`, then click `grpc_unity_package.*.*.*-dev.zip` to download the library. See [gRPC C# - experimental support for Unity](https://github.com/grpc/grpc/tree/master/src/csharp/experimental#unity) for details.

> **NOTE**: If you encounter error about `Google.Protobuf.dll`, you can remove the library. MagicOnion does not depend `Google.Protobuf.dll`. ([Issue#296](https://github.com/Cysharp/MagicOnion/issues/296))

> **NOTE**: gRPC native library for iOS has a file size of over 100MB, which may cause problems when pushing to GitHub or others. For more information on solutions, see [Stripping debug symbols from ios/libgrpc.a](#stripping-debug-symbols-from-ioslibgrpca).

### MessagePack for C#
MessagePack for C# is not included in MagicOnion package. You need to download and install separately.

See [MessagePack for C# installation for Unity](https://github.com/neuecc/MessagePack-CSharp#unity) for details.

### MagicOnion code generator (for IL2CPP)

MagicOnion's default client only supports Unity Editor or non-IL2CPP environments (e.g. Windows/macOS/Linux Standalone). If you want to use MagicOnion on IL2CPP environments, you need to generate a client and register it in your Unity project.

#### MessagePack for C#
For the same reason, MessagePack for C# code generation is also required.

See [MessagePack-CSharp AOT Code Generation (to support Unity/Xamarin)
](https://github.com/neuecc/MessagePack-CSharp#aot-code-generation-to-support-unityxamarin) section for more details about MessagePack code generation.

MagicOnion code generator also generates code for MessagePack and requires Resolver registration.

```csharp
[RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.BeforeSceneLoad)]
static void RegisterResolvers()
{
    // NOTE: Currently, CompositeResolver doesn't work on Unity IL2CPP build. Use StaticCompositeResolver instead of it.
    StaticCompositeResolver.Instance.Register(
        // This resolver is generated by MagicOnion's code generator.
        MagicOnion.Resolvers.MagicOnionResolver.Instance,
        // This resolver is generated by MessagePack's code generator.
        MessagePack.Resolvers.GeneratedResolver.Instance,
        StandardResolver.Instance
    );

    MessagePackSerializer.DefaultOptions = MessagePackSerializer.DefaultOptions
        .WithResolver(StaticCompositeResolver.Instance);
}
```

#### `moc` (MagicOnion Codegen) command line tool
`moc` is a cross-platform application. It requires [.NET Core 3.1 SDK](https://dotnet.microsoft.com/download) to run it.

You can download a binary from [Releases](https://github.com/cysharp/MagicOnion/releases) page in this repository or install the tool as .NET Core tools. We recommend installing it as a local tool for .NET Core tools because of its advantages, such as fixing version per project.

To install as a [.NET Core tools (local tool)](https://docs.microsoft.com/en-us/dotnet/core/tools/global-tools#install-a-local-tool), you can run the following command:

```bash
dotnet new tool-manifest
dotnet tool install MagicOnion.Generator
```

If `moc` is installed as a local tool, you can run it with `dotnet moc` command.

```bash
$ dotnet moc --help

Usage:  [options...]

MagicOnion Code Generator generates client codes for Ahead-of-Time compilation.

Options:
  -i, --input <String>                              The path to the project (.csproj) to generate the client. (Required)
  -o, --output <String>                             The generated file path (single file) or the directory path to generate the files (multiple files). (Required)
  -u, --no-use-unity-attr                           Do not use UnityEngine's RuntimeInitializeOnLoadMethodAttribute on MagicOnionInitializer. (Same as --disable-auto-register) (Optional)
  -d, --disable-auto-register                       Do not automatically call MagicOnionInitializer during start-up. (Automatic registration requires .NET 5+ or Unity) (Optional)
  -n, --namespace <String>                          The namespace of clients to generate. (Default: MagicOnion)
  -m, --messagepack-formatter-namespace <String>    The namespace of pre-generated MessagePackFormatters. (Default: MessagePack.Formatters)
  -c, --conditional-symbol <String>                 The conditional compiler symbols used during code analysis. The value is split by ','. (Default: null)
  -v, --verbose                                     Enable verbose logging (Optional)
  -s, --serializer <SerializerType>                 The serializer used for message serialization (Default: MessagePack)
```

```bash
dotnet moc -i ./Assembly-CSharp.csproj -o Assets/Scripts/MagicOnion.Generated.cs
```

### gRPC channel management integration for Unity
Wraps gRPC channels and provides a mechanism to manage them with Unity's lifecycle.
This prevents your application and the Unity Editor from freezing by releasing channels and StreamingHub in one place.

The editor extension also provides the ability to display the communication status of channels.

![](https://user-images.githubusercontent.com/9012/111609638-da21a800-881d-11eb-81b2-33abe80ea497.gif)

> **NOTE**: The data rate is calculated only for the message body of methods, and does not include Headers, Trailers, or Keep-alive pings.

#### New APIs
- `MagicOnion.GrpcChannelx` class
  - `GrpcChannelx.ForTarget(GrpcChannelTarget)` method
  - `GrpcChannelx.ForAddress(Uri)` method
  - `GrpcChannelx.ForAddress(string)` method
- `MagicOnion.Unity.GrpcChannelProviderHost` class
  - `GrpcChannelProviderHost.Initialize(IGrpcChannelProvider)` method
- `MagicOnion.Unity.IGrpcChannelProvider` interface
  - `DefaultGrpcChannelProvider` class
  - `LoggingGrpcChannelProvider` class

#### Usages
##### 1. Prepare to use `GrpcChannelx` in your Unity project.
Before creating a channel in your application, you need to initialize the provider host to be managed.

```csharp
[RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.BeforeSceneLoad)]
public static void OnRuntimeInitialize()
{
    // Initialize gRPC channel provider when the application is loaded.
    GrpcChannelProviderHost.Initialize(new DefaultGrpcChannelProvider(new []
    {
        // send keepalive ping every 5 second, default is 2 hours
        new ChannelOption("grpc.keepalive_time_ms", 5000),
        // keepalive ping time out after 5 seconds, default is 20 seconds
        new ChannelOption("grpc.keepalive_timeout_ms", 5 * 1000),
    }));
}
```

GrpcChannelProviderHost will be created as DontDestroyOnLoad and keeps existing while the application is running. DO NOT destory it.

![image](https://user-images.githubusercontent.com/9012/111586444-2eb82980-8804-11eb-8a4f-a898c86e5a60.png)

##### 2. Use `GrpcChannelx.ForTarget` or `GrpcChannelx.ForAddress` to create a channel.
Use `GrpcChannelx.ForTarget` or `GrpcChannelx.ForAddress` to create a channel instead of `new Channel(...)`.

```csharp
var channel = GrpcChannelx.ForTarget(new GrpcChannelTarget("localhost", 12345, ChannelCredentials.Insecure));
// or
var channel = GrpcChannelx.ForAddress("http://localhost:12345");
```

##### 3. Use the channel instead of `Grpc.Core.Channel`.
```csharp
var channel = GrpcChannelx.ForAddress("http://localhost:12345");

var serviceClient = MagicOnionClient.Create<IGreeterService>(channel);
var hubClient = StreamingHubClient.ConnectAsync<IGreeterHub, IGreeterHubReceiver>(channel, this);
```

##### Extensions for Unity Editor (Editor Window & Inspector)
![image](https://user-images.githubusercontent.com/9012/111585700-0d0a7280-8803-11eb-8ce3-3b8f9d968c13.png)


## iOS build with gRPC
gRPC iOS build require two additional operation on build.

1. Disable Bitcode
1. Add libz.tbd

We introduce OnPostProcessingBuild sample [BuildIos.cs](https://github.com/Cysharp/MagicOnion/blob/master/samples/ChatApp/ChatApp.Unity/Assets/Editor/BuildeIos.cs) for ChatApp.Unity to automate these steps.

```csharp
#if UNITY_IPHONE
using System.IO;
using UnityEngine;
using UnityEditor;
using UnityEditor.Callbacks;
using UnityEditor.iOS.Xcode;

public class BuildIos
{
    /// <summary>
    /// Handle libgrpc project settings.
    /// </summary>
    /// <param name="target"></param>
    /// <param name="path"></param>
    [PostProcessBuild(1)]
    public static void OnPostProcessBuild(BuildTarget target, string path)
    {
        var projectPath = PBXProject.GetPBXProjectPath(path);
        var project = new PBXProject();
        project.ReadFromString(File.ReadAllText(projectPath));
        var targetGuid = project.TargetGuidByName(PBXProject.GetUnityTargetName());

        // libz.tbd for grpc ios build
        project.AddFrameworkToProject(targetGuid, "libz.tbd", false);

        // libgrpc_csharp_ext missing bitcode. as BITCODE exand binary size to 250MB.
        project.SetBuildProperty(targetGuid, "ENABLE_BITCODE", "NO");

        File.WriteAllText(projectPath, project.WriteToString());
    }
}
#endif
```

## Stripping debug symbols from ios/libgrpc.a
When you download gRPC daily build and extract Native Libraries for Unity, you will find file size of Plugins/Grpc.Core/runtime/ios/libgrpc.a beyonds 100MB. GitHub will reject commit when file size is over 100MB, therefore libgrpc.a often become unwelcome for gif-low.
The reason of libgrpc.a file size is because it includes debug symbols for 3 architectures, arm64, armv7 and x86_64.

We introduce strip debug symbols and generate reduced size `libgrpc_stripped.a`, it's about 17MB.
This may useful for whom want commit `libgrpc.a` to GitHub, and understanding stripped library missing debug symbols.

**How to strip**

Download gRPC lib `grpc_unity_package.*.*.*-dev.zip` from [gRPC daily builds](https://packages.grpc.io/) and extract it, copy Plugins folder to Unity's Assets path.

Open terminal on `Plugins/Grpc.Core/runtimes/ios/` and execute following will generate `libgrpc_stripped.a` and replace original libgrpc.a with stripped version.

```shell
$ cd ${UNITY_PATH}/Plugins/Grpc.Core/runtimes/ios
$ strip -S -x libgrpc.a -o libgrpc_stripped.a
$ rm libgrpc.a && mv libgrpc_stripped.a libgrpc.a
```

Make sure you can build app with iOS and works fine.

## Stripping debug symbols from libgrpc_csharp_ext.so
Plugins/Grpc.Core/runtime/android/[arch]/libgrpc_csharp_ext.so file size is big because its includes debug symbols.

You can reduce its size using strip (this command is includes in the NDK).

```shell
$ cd ${UNITY_PATH}/Plugins/Grpc.Core/runtime/android/${TARGET_ARCH}
$ strip.exe libgrpc_csharp_ext.so
```

## Workaround for il2cpp + Windows Build failure
If you do a Windows il2cpp build with the gRPC daily build, the build may fail with following error messages.

```
20AAB1A42EE7F9CA535031CD347327DE.obj : error LNK2019: unresolved external symbol dlopen referenced in function Mono_dlopen_m7F2DE2CD0870AB15EEA4E0A0BA6C47044E74BB67
20AAB1A42EE7F9CA535031CD347327DE.obj : error LNK2019: unresolved external symbol dlerror referenced in function Mono_dlerror_m359ABCFD23D0EB5314DE2DFF8AB58CFE949BBABD
20AAB1A42EE7F9CA535031CD347327DE.obj : error LNK2019: unresolved external symbol dlsym referenced in function Mono_dlsym_m31A00C09F598C9D552A94628C2C28B3C7B04C2DD
C:\Path\To\MyProject\Library\il2cpp_cache\linkresult_C1E926E002526A4D380E4B12B6BD0522\GameAssembly.dll : fatal error LNK1120: 3 unresolved externals
```

The reason is because some native function (but not nessessary at the runtime) not found on Windows il2cpp build.
You can avoid this problem by adding the following code to `grpc_csharp_ext_dummy_stubs.c`.

```c
void* dlopen(const char* filename, int flags) {
  fprintf(stderr, "Should never reach here");
  abort();
}
char* dlerror(void) {
  fprintf(stderr, "Should never reach here");
  abort();
}
void* dlsym(void* handle, const char* symbol) {
  fprintf(stderr, "Should never reach here");
  abort();
}
```

## gRPC Keepalive
When you want detect network termination on Client or vice-versa, you can configure gRPC Keepalive.

### Applied to .NET Standard 2.1 platforms (Grpc.Net.Client)
See [keep alive pings | Performance best practices with gRPC | Microsoft Docs](https://docs.microsoft.com/en-us/aspnet/core/grpc/performance?view=aspnetcore-5.0#keep-alive-pings) for information on setting up keepalive for Grpc.Net.Client.

### Applied to .NET Standard 2.0 or Unity platforms (Grpc.Core)
Follow to the [Keepalive UserGuide for gRPC Core](https://github.com/grpc/grpc/blob/master/doc/keepalive.md) but let's see how in actual.

**ChannelOption**

ChannelOptions is primitive way to configure options.
Below uses `ChannelOption` and offer keepalive for every 10 second even RPC is not called.

```csharp
// If you want configure KEEP_ALIVE interval, then....
// * set same value for `grpc.keepalive_time_ms` and `grpc.http2.min_time_between_pings_ms`
// * keep `grpc.http2.min_ping_interval_without_data_ms < grpc.http2.min_time_between_pings_ms`
var options = new[]
{
    // send keepalive ping every 10 second, default is 2 hours
    new ChannelOption("grpc.keepalive_time_ms", 10000),
    // keepalive ping time out after 5 seconds, default is 20 seconds
    new ChannelOption("grpc.keepalive_timeout_ms", 5000),
    // allow grpc pings from client every 10 seconds
    new ChannelOption("grpc.http2.min_time_between_pings_ms", 10000),
    // allow unlimited amount of keepalive pings without data
    new ChannelOption("grpc.http2.max_pings_without_data", 0),
    // allow keepalive pings when there's no gRPC calls
    new ChannelOption("grpc.keepalive_permit_without_calls", 1),
    // allow grpc pings from client without data every 5 seconds
    new ChannelOption("grpc.http2.min_ping_interval_without_data_ms", 5000),
};
```

Pass this options to Channel on Client will configure Keepalive.

```csharp
// Client
this.channel = new Channel("localhost", 12345, ChannelCredentials.Insecure, options);
```

Now you can detect client network disconnection on serverside, let's override `OnDisconnected` and set debugger, disconnect Client network and wait for interval sec!

## HTTPS (TLS)
MagicOnion supports TLS encrypted connection.

### Server-side
In general, HTTPS encryption settings on the server follow ASP.NET Core. For more information, see [Enforce HTTPS in ASP.NET Core | Microsoft Docs](https://docs.microsoft.com/ja-jp/aspnet/core/security/enforcing-ssl).

> **NOTE**: The limitations on macOS environment and when running on Docker are also described in ASP.NET Core documentation.

### Client-side
Depending on whether the client supports .NET Standard 2.1 or .NET Standard 2.1 (including Unity), the configuration is different.

#### .NET Standard 2.1 (.NET Core 3.x, .NET 5, Xamarin)
If the client supports .NET Standard 2.1 or newer, MagicOnion uses `Grpc.Net.Client` (a pure C# implementation) for gRPC connection.

Grpc.Net.Client uses `HttpClient` internally, so it handles certificates the same way as `HttpClient`. For example, on Windows, it uses Windows's certificate store to validate certificates.

#### .NET Standard 2.0 (.NET Core 2.x, .NET Framework 4.6.1+) / Unity
If the client supports .NET Standard 2.0, MagicOnion uses `Grpc.Core` (C-library binding) for gRPC connection.

Grpc.Core has its [own certificate store built into the library](https://github.com/grpc/grpc/blob/master/etc/roots.pem) and uses it unless you specify a certificate. This certificate store contains common CAs and is rarely a problem in production environment.

However, there is a problem when connecting with a server using [ASP.NET Core development certificate](https://docs.microsoft.com/en-us/aspnet/core/security/enforcing-ssl?view=aspnetcore-5.0&tabs=visual-studio#trust-the-aspnet-core-https-development-certificate-on-windows-and-macos). For example, if you see the following exceptions when you try to connect, the server certificate validation may have failed.

```
Grpc.Core.RpcException: 'Status(StatusCode="Unavailable", Detail="failed to connect to all addresses", ...')
```

The following workarounds are suggested for such cases:

- Issue and configure a trusted certificate to the server
- Use OpenSSL commands to issue and configure self-signed certificates to servers and clients
- Unencrypted connection without TLS

### Use HTTP unencrypted connection without TLS
It is recommended to use HTTPS for server-client connection, but in some cases during development you may want to configure unencrypted connection. Also, you need to configure unencrypted connection in macOS because ALPN over TLS is not supported.

#### Server-side
To allow your server to accept unencrypted HTTP/2, you must configure an endpoint to listen to Kestrel. Endpoints can be configured either by using `appsettings.json` or directly in the source code.

See also [Unable to start ASP.NET Core gRPC app on macOS | Troubleshoot gRPC on .NET Core](https://docs.microsoft.com/en-us/aspnet/core/grpc/troubleshoot#unable-to-start-aspnet-core-grpc-app-on-macos) for details.

```json
{
    ...
    "Kestrel": {
        "Endpoints": {
            "Grpc": {
                "Url": "http://localhost:5000",
                "Protocols": "Http2"
            },
            "Https": {
                "Url": "https://localhost:5001",
                "Protocols": "Http1AndHttp2"
            },
            "Http": {
                "Url": "http://localhost:5002",
                "Protocols": "Http1"
            }
        }
    },
    ...
}
```

```csharp
webBuilder
    .UseKestrel(options =>
    {
        // WORKAROUND: Accept HTTP/2 only to allow insecure HTTP/2 connections during development.
        options.ConfigureEndpointDefaults(endpointOptions =>
        {
            endpointOptions.Protocols = HttpProtocols.Http2;
        });
    })
    .UseStartup<Startup>();
```

#### Client-side (.NET Standard 2.1; Grpc.Net.Client)
When calling `GrpcChannel.ForAddress`, change the URL scheme to HTTP and the port to an unencrypted port.

```csharp
var channel = GrpcChannel.ForAddress("http://localhost:5000");
```

Enable AppSwitch to allow HTTP/2 without encryption.

```csharp
// WORKAROUND: Use insecure HTTP/2 connections during development.
AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);
```

See also [Call insecure gRPC services with .NET Core client | Troubleshoot gRPC on .NET Core | Microsoft Docs](https://docs.microsoft.com/en-us/aspnet/core/grpc/troubleshoot#call-insecure-grpc-services-with-net-core-client) for details.

#### Client-side (.NET Standard 2.0/Unity; Grpc.Core)
When creating `Channel`, specify the unencrypted port and pass `ChannelCredentials.Insecure`.

```csharp
var channel = new Channel("localhost", 5000, ChannelCredentials.Insecure);
```

#### Limitations
If unencrypted HTTP/2 connection is accepted, HTTP/1 and HTTP/2 cannot be served on the same port.
When TLS is enabled, ALPN is used for HTTP/2 negotiation, but with non-TLS, this is not possible.

If you want HTTP/1 and HTTP/2 to work together for the convenience of hosting a web site or API, you can listen on multiple ports by configuring Kestrel.

## Deployment
MagicOnion is also supported in Docker containers and running on Kubernetes.

See [docs/articles/deployment/](docs/articles/deployment/) for information on deploying to Amazon Web Service and other cloud services.

## Integrations
### Swagger
MagicOnion has built-in HTTP/1.1 JSON Gateway and [Swagger](http://swagger.io/) integration for Unary operation. It can execute and debug RPC-API easily.

```bash
dotnet add package MagicOnion.Server.HttpGateway
```

```csharp
public class Startup
{
    public Startup(IConfiguration configuration)
    {
        Configuration = configuration;
    }

    public IConfiguration Configuration { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllersWithViews();

        services.AddGrpc(); // MagicOnion depends on ASP.NET Core gRPC service.
        services.AddMagicOnion();
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        app.UseRouting();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapMagicOnionHttpGateway("_", app.ApplicationServices.GetService<MagicOnion.Server.MagicOnionServiceDefinition>().MethodHandlers, GrpcChannel.ForAddress("https://localhost:5001"));
            endpoints.MapMagicOnionSwagger("swagger", app.ApplicationServices.GetService<MagicOnion.Server.MagicOnionServiceDefinition>().MethodHandlers, "/_/");

            endpoints.MapMagicOnionService();
        });
    }
}
```

Open `http://localhost:5000`, you can see swagger view.

![image](https://cloud.githubusercontent.com/assets/46207/21295663/6a9d3e28-c59d-11e6-8081-18d14e359567.png)

## Advanced
### MagicOnionOption

`MagicOnionOption` can pass to `MagicOnionEngine.BuildServerServiceDefinition(MagicOnionOptions option)`.

| Property | Description |
| --- | --- |
| `IList<MagicOnionFilterDescriptor>` GlobalFilters | Global MagicOnion filters. |
| `bool` EnableCurrentContext | Enable ServiceContext.Current option by AsyncLocal, default is false. |
| `IList<StreamingHubFilterDescriptor>` Global StreamingHub filters. | GlobalStreamingHubFilters |
| `IGroupRepositoryFactory` DefaultGroupRepositoryFactory | Default GroupRepository factory for StreamingHub, default is ``. |
| `bool` IsReturnExceptionStackTraceInErrorDetail | If true, MagicOnion handles exception ownself and send to message. If false, propagate to gRPC engine. Default is false. |
| `MessagePackSerializerOptions` SerializerOptions | MessagePack serialization resolver. Default is used ambient default(MessagePackSerializer.DefaultOptions). |

### Internal Logging
`IMagicOnionLogger` is structured logger of MagicOnion internal information.

 Implements your custom logging code and append it, default is `NullMagicOnionLogger`(do nothing). MagicOnion has some built in logger, `MagicOnionLogToLogger` that structured log to string log and send to `Microsoft.Extensions.Logging.ILogger`.

### Raw gRPC APIs
MagicOnion can define and use primitive gRPC APIs(ClientStreaming, ServerStreaming, DuplexStreaming). Especially DuplexStreaming is used underlying StreamingHub. If there is no reason, we recommend using StreamingHub.

```csharp
// Definitions
public interface IMyFirstService : IService<IMyFirstService>
{
    UnaryResult<string> SumAsync(int x, int y);
    Task<UnaryResult<string>> SumLegacyTaskAsync(int x, int y);
    Task<ClientStreamingResult<int, string>> ClientStreamingSampleAsync();
    Task<ServerStreamingResult<string>> ServerStreamingSampleAsync(int x, int y, int z);
    Task<DuplexStreamingResult<int, string>> DuplexStreamingSampleAsync();
}

// Server
public class MyFirstService : ServiceBase<IMyFirstService>, IMyFirstService
{
    // VisualStudio 2017(C# 7.0), Unity 2018.3+ supports return `async UnaryResult` directly
    // I recommend disable async-warning on project level. <NoWarn>1998</NoWarn>
    public async UnaryResult<string> SumAsync(int x, int y)
    {
        Logger.Debug($"Called SumAsync - x:{x} y:{y}");

        return (x + y).ToString();
    }

    // VS2015(C# 6.0), Unity 2018.2 use Task
    public async Task<UnaryResult<string>> SumLegacyTaskAsync(int x, int y)
    {
        Logger.Debug($"Called SumAsync - x:{x} y:{y}");

        // use UnaryResult method.
        return UnaryResult((x + y).ToString());
    }

    public async Task<ClientStreamingResult<int, string>> ClientStreamingSampleAsync()
    {
        Logger.Debug($"Called ClientStreamingSampleAsync");

        // If ClientStreaming, use GetClientStreamingContext.
        var stream = GetClientStreamingContext<int, string>();

        // receive from client asynchronously
        await foreach (var x in stream.ReadAllAsync())
        {
            Logger.Debug("Client Stream Received:" + x);
        }

        // StreamingContext.Result() for result value.
        return stream.Result("finished");
    }

    public async Task<ServerStreamingResult<string>> ServerStreamingSampleAsync(int x, int y, int z)
    {
        Logger.Debug($"Called ServerStreamingSampleAsync - x:{x} y:{y} z:{z}");

        var stream = GetServerStreamingContext<string>();

        var acc = 0;
        for (int i = 0; i < z; i++)
        {
            acc = acc + x + y;
            await stream.WriteAsync(acc.ToString());
        }

        return stream.Result();
    }

    public async Task<DuplexStreamingResult<int, string>> DuplexStreamingSampleAsync()
    {
        Logger.Debug($"Called DuplexStreamingSampleAsync");

        // DuplexStreamingContext represents both server and client streaming.
        var stream = GetDuplexStreamingContext<int, string>();

        var waitTask = Task.Run(async () =>
        {
            // ForEachAsync(MoveNext, Current) can receive client streaming.
            await foreach (var x in stream.ReadAllAsync())
            {
                Logger.Debug($"Duplex Streaming Received:" + x);
            }
        });

        // WriteAsync is ServerStreaming.
        await stream.WriteAsync("test1");
        await stream.WriteAsync("test2");
        await stream.WriteAsync("finish");

        await waitTask;

        return stream.Result();
    }
}
```

Client sample.

```csharp
static async Task UnaryRun(IMyFirstService client)
{
    // await(C# 7.0, Unity 2018.3+)
    var vvvvv = await client.SumAsync(10, 20);
    Console.WriteLine("SumAsync:" + vvvvv);

    // if use Task<UnaryResult>(Unity 2018.2), use await await
    var vvvv2 = await await client.SumLegacyTaskAsync(10, 20);
}

static async Task ClientStreamRun(IMyFirstService client)
{
    var stream = await client.ClientStreamingSampleAsync();

    for (int i = 0; i < 3; i++)
    {
        await stream.RequestStream.WriteAsync(i);
    }
    await stream.RequestStream.CompleteAsync();

    var response = await stream.ResponseAsync;

    Console.WriteLine("Response:" + response);
}

static async Task ServerStreamRun(IMyFirstService client)
{
    var stream = await client.ServerStreamingSampleAsync(10, 20, 3);

    await foreach (var x in stream.ResponseStream.ReadAllAsync())
    {
        Console.WriteLine("ServerStream Response:" + x);
    }
}

static async Task DuplexStreamRun(IMyFirstService client)
{
    var stream = await client.DuplexStreamingSampleAsync();

    var count = 0;
    await foreach (var x in stream.ResponseStream.ReadAllAsync())
    {
        Console.WriteLine("DuplexStream Response:" + x);

        await stream.RequestStream.WriteAsync(count++);
        if (x == "finish")
        {
            await stream.RequestStream.CompleteAsync();
        }
    }
}
```

### Zero deserialization mapping
In RPC, especially in real-time communication involving frequent transmission of data, it is often the serialization process where data is converted before being sent that limits the performance. In MagicOnion, serialization is done by my MessagePack for C#, which is the fastest binary serializer for C#, so it cannot be a limiting factor. Also, in addition to performance, it also provides flexibility regarding data in that variables of any type can be sent as long as they can be serialized by MessagePack for C#.

Also, taking advantage of the fact that both the client and the server run on C# and data stored on internal memory are expected to share the same layout, I added an option to do mapping through memory copy without serialization/deserialization in case of a value-type variable.

Especially in Unity, this is can combinate with `MessagePack.UnityShims` package of NuGet.

```csharp
// It supports standard struct-type variables that are provided by Unity, such as Vector3, and arrays containing them, as well as custom struct-type variables and their arrays.
// I recommend doing this explicitly using [StructLayout(LayoutKind.Explicit)] to accurately match the size.
public struct CustomStruct
{
    public long Id;
    public int Hp;
    public int Mp;
    public byte Status;
}

// ---- Register the following code when initializing.

// By registering it, T and T[] can be handled using zero deserialization mapping.
UnsafeDirectBlitResolver.Register<CustomStruct>();

// The struct-type above as well as Unity-provided struct-types (Vector2, Rect, etc.), and their arrays are registered as standards.
CompositeResolver.RegisterAndSetAsDefault(
    UnsafeDirectBlitResolver.Instance,
    MessagePack.Unity.Extension.UnityBlitResolver.Instance
    );

// --- Now the communication will be in the format above when they are used for transmission.
await client.SendAsync(new CustomStruct { Hp = 99 });
```

Nothing needs to be processed here, so it promises the best performance theoretically possible in terms of transmission speed. However, since these struct-type variables need to be copied, I recommend handling everything as ref as a rule when you need to define a large struct-type, or it might slow down the process.

I believe that this can be easily and effectively applied to sending a large number of Transforms, such as an array of Vector3 variables.

### Customizing message serialization
MagicOnion uses MessagePack for serialization by default, but it also provides extension points to customize serialization.

It allows for customization, such as encryption and the using of serializers other than MessagePack.

```csharp
/// <summary>
/// Provides a serializer for request/response of MagicOnion services and hub methods.
/// </summary>
public interface IMagicOnionSerializerProvider
{
    IMagicOnionSerializer Create(MethodType methodType, MethodInfo? methodInfo);
}

/// <summary>
/// Provides a processing for message serialization.
/// </summary>
public interface IMagicOnionSerializer
{
    void Serialize<T>(IBufferWriter<byte> writer, in T? value);
    T? Deserialize<T>(in ReadOnlySequence<byte> bytes);
}

public static class MagicOnionSerializerProvider
{
    /// <summary>
    /// Gets or sets the <see cref="IMagicOnionSerializerProvider"/> to be used by default.
    /// </summary>
    public static IMagicOnionSerializerProvider Default { get; set; } = MessagePackMagicOnionSerializerProvider.Default;
}
```

#### MemoryPack support
MagicOnion also supports MemoryPack as a message serializer. (preview)

```
dotnet add package MagicOnion.Serialization.MemoryPack
```

Set `MemoryPackMagicOnionSerializerProvider` to `MagicOnionSerializerProvider` on the client and server to serialize using MemoryPack.

```csharp
MagicOnionSerializerProvider.Default = MemoryPackMagicOnionSerializerProvider.Instance;

// or

await StreamingHubClient.ConnectAsync<IMyHub, IMyHubReceiver>(channel, receiver, serializerProvider: MemoryPackMagicOnionSerializerProvider.Instance);
MagicOnionClient.Create<IMyService>(channel, MemoryPackMagicOnionSerializerProvider.Instance);
```

If you want to use MagicOnion.Generator (moc), you need to specify `--serializer MemoryPack` as an option. The generated code will use MemoryPack instead of MessagePack.

The application must also call `MagicOnionMemoryPackFormatterProvider.RegisterFormatters()` on startup.

## Experimentals
### OpenTelemetry
MagicOnion.OpenTelemetry is implementation of [open\-telemetry/opentelemetry\-dotnet: OpenTelemetry \.NET SDK](https://github.com/open-telemetry/opentelemetry-dotnet), so you can use any OpenTelemetry exporter, like [Jaeger](https://www.jaegertracing.io/), [Zipkin](https://zipkin.io/), [StackDriver](https://cloud.google.com/stackdriver) and others.

See details at [MagicOnion.Server.OpenTelemetry](src/MagicOnion.Server.OpenTelemetry)

## License
This library is under the MIT License.