.NET7 gRPC JSON转码+OpenAPI _生活百科

gRPC JSON转码gRPC JSON 转码允许浏览器应用调用 gRPC 服务，就像它们是使用 JSON 的 RESTful API 一样。

浏览器应用不需要生成 gRPC 客户端或了解 gRPC 的任何信息。
通过使用 HTTP 元数据注释 .proto 文件，可从 gRPC 服务自动创建 RESTful API 。
使应用可以同时支持 gRPC 和 JSON Web API ，而无需重复为两者生成单独的服务。

OpenAPI与gRPC ServerOpenAPI（以前称为 Swagger）是一个与语言无关的规范，用于描述 API 。gRPC JSON 转码支持从转码 REST ful的 API 生成 OpenAPI 。
实现Server端通过VS新增GRPC Server ，新增nuget包
<ItemGroup><PackageReference Include="Grpc.AspNetCore" Version="2.49.0" /><PackageReference Include="Microsoft.AspNetCore.Grpc.JsonTranscoding" Version="7.0.0" /><PackageReference Include="Microsoft.AspNetCore.Grpc.Swagger" Version="0.3.0" /></ItemGroup>为api生成用于OpenAPI的注释XML文件，在Server.csproj文件中新增以下配置
<GenerateDocumentationFile>true</GenerateDocumentationFile>Server的Program.cs中，开启JSON转码与Swagger
var builder = WebApplication.CreateBuilder(args);// 开启JSON转码builder.Services.AddGrpc().AddJsonTranscoding();// 配置Swaggerbuilder.Services.AddGrpcSwagger();builder.Services.AddSwaggerGen(c =>{c.SwaggerDoc("v1", new OpenApiInfo { Title = "gRPC transcoding", Version = "v1" });var filePath = Path.Combine(System.AppContext.BaseDirectory, "GrpcService4.xml");c.IncludeXmlComments(filePath);c.IncludeGrpcXmlComments(filePath, includeControllerXmlComments: true);});var app = builder.Build();//开启Swaggerapp.UseSwagger();app.UseSwaggerUI(c =>{c.SwaggerEndpoint("/swagger/v1/swagger.json", "My API V1");});app.MapGrpcService<GreeterService>();app.MapGet("/", () => "Communication with gRPC endpoints must be made through a gRPC client. To learn how to create a client, visit: https://go.microsoft.com/fwlink/?linkid=2086909");app.Run();下载GRPC JSON转码依赖的proto文件
https://github.com/dotnet/aspnetcore/blob/main/src/Grpc/JsonTranscoding/test/testassets/Sandbox/google/api/http.proto
https://github.com/dotnet/aspnetcore/blob/main/src/Grpc/JsonTranscoding/test/testassets/Sandbox/google/api/annotations.proto
并将文件放到项目的google/api/文件夹中。
修改greet.proto文件，通过option开启http选项，以一个get方法和一个post方法举例
syntax = "proto3";import "google/api/annotations.proto";option csharp_namespace = "GrpcService4";package greet;// The greeting service definition.service Greeter {// Sends a greetingrpc SayHello (HelloRequest) returns (HelloReply){option (google.api.http) = {get: "/v1/greeter/{name}"};};// Sends a greetingrpc SayHelloPost (HelloRequestPost) returns (HelloReply){option (google.api.http) = {post: "/v1/greeter/post",body:"data"};};}// The request message containing the user's name.message HelloRequest {string name = 1;}// The request message containing the user's name.message HelloRequestPost {HelloRequestPostData data = https://www.huyubaike.com/biancheng/1;}message HelloRequestPostData{string name = 1;string gender = 2;}// The response message containing the greetings.message HelloReply {string message = 1;}然后实现Server
using Grpc.Core;using GrpcService4;namespace GrpcService4.Services{public class GreeterService : Greeter.GreeterBase{private readonly ILogger<GreeterService> _logger;public GreeterService(ILogger<GreeterService> logger){_logger = logger;}public override Task<HelloReply> SayHello(HelloRequest request, ServerCallContext context){return Task.FromResult(new HelloReply{Message = "Hello " + request.Name});}public override Task<HelloReply> SayHelloPost(HelloRequestPost request, ServerCallContext context){return Task.FromResult(new HelloReply{Message = "Hello " + request.Data.Name});}}}至此server的json转码开启完成，运行服务，访问swagger，即可尝试http方式请求

文章插图
在支持http方式的请求的情况下，同时支持grpc请求。
实现Client端新增控制台项目，添加以下nuget
<ItemGroup><PackageReference Include="Google.Protobuf" Version="3.21.9" /><PackageReference Include="Grpc.Net.Client" Version="2.49.0" /><PackageReference Include="Microsoft.AspNetCore.Grpc.JsonTranscoding" Version="7.0.0" /><PackageReference Include="Grpc.Tools" Version="2.50.0"><PrivateAssets>all</PrivateAssets><IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets></PackageReference></ItemGroup>包含与server端相同的proto文件
<ItemGroup><Protobuf Include="Protos\greet.proto" GrpcServices="Client" /></ItemGroup>尝试请求Server
static async Task Main(string[] args){using var channel = GrpcChannel.ForAddress("https://localhost:7167");var client = new Greeter.GreeterClient(channel);var reply = await client.SayHelloAsync(new HelloRequest { Name = "GreeterClient" });Console.WriteLine("Greeting: " + reply.Message);var replyPost = await client.SayHelloPostAsync(new HelloRequestPost { Data = https://www.huyubaike.com/biancheng/new HelloRequestPostData { Name ="111" } });Console.WriteLine("Greeting: " + replyPost.Message);Console.WriteLine("Press any key to exit...");Console.ReadKey();}