Dapr 运用
- 前置条件
- Docker
- Win10
Dapr 部署
本文将采用本地部署的方式。
安装 Dapr CLI
打开 Windows PowerShell 或 cmd ,运行以下命令以安装 Dapr CLI
,并添加安装路径到系统环境变量中。
powershell -Command "iwr -useb https://raw.githubusercontent.com/dapr/cli/master/install/install.ps1 | iex"
这里安装可能会失败。如果失败可以手动安装。
- 打开 Dapr 发布页面下载
dapr_windows_amd64.zip
- 解压文件 zip 文件
- 把解压后的文件拷贝到
C:\dapr
中
安装 MySql
Docker 启动 Mysql
docker run --name mysqltest -e MYSQL_ROOT_PASSWORD=123456 -d mysql
使用 Dapr CLI 安装 Darp runtime
在 Windows PowerShell 或 cmd 中使用命令 dapr init
以安装 Dapr。
同时可以在 Docker 中查看 Dapr 容器。
至此,一个本地 Dapr 服务搭建完成。
使用 Asp.Net Core
搭建 ProductService 服务
ProductService 提供两个服务
- 获取所有产品集合
- 添加产品
使用
ASP.Net Core
创建 ProductService ,具体参考源码Dapr 启动 ProductService
dapr run --app-id productService --app-port 5000 dotnet run
获取所有产品集合,使用 curl 命令
curl -X GET http://localhost:5000/getlist
或者
curl -X GET http://localhost:54680/v1.0/invoke/productService/method/getlist
添加一个产品
curl -X POST https://localhost:5001/product -H "Content-Type: application/json" -d "{ \"id\": \"14a3611d-1561-455f-9c72-381eed2f6ee3\" }"
重点,通过 Dapr 添加一个产品,先看添加产品的代码
///
/// 创建产品 /// /// 产品创建模型 ///[Topic("product")] [HttpPost("product")] public async Task CreateProduct(ProductCreate productCreate) { _productContext.Products.Add(new Product { ProductID = productCreate.ID }); return await _productContext.SaveChangesAsync() == 1; } 使用 Dapr cli 发布事件
dapr invoke -a productService -m product -p "{\"id\":\"b1ccf14a-408a-428e-b0f0-06b97cbe4135\"}"
输出为:
true App invoked successfully
使用 curl 命令直接请求 ProductService 地址
curl -X POST http://localhost:5000/product -H "Content-Type: application/json" -d "{ \"id\": \"14a3611d-1561-455f-9c72-381eed2f64e3\" }"
输出为:
true
使用 curl 命令通过 Dapr runtime
curl -X POST http://localhost:54680/v1.0/invoke/productService/method/product -H "Content-Type: application/json" -d "{ \"id\": \"14a3611d-1561-455f-9c72-381eed2f54e3\" }"
输出为:
true
注意:
- Dapr 使用 App 端口号应与服务端口号相同,例如:
ASP.Net Core
服务端口号为5000,则在使用 Dapr 托管应用程序时的端口号也应使用 5000
至此, ProductService 创建完成。
使用 Golang 创建 gRPC Server
创建 Server
package main import ( "context" "fmt" "log" "net" "github.com/golang/protobuf/ptypes/any" "github.com/golang/protobuf/ptypes/empty" pb "github.com/dapr/go-sdk/daprclient" "google.golang.org/grpc" ) // server is our user app type server struct { } func main() { // create listiner lis, err := net.Listen("tcp", ":4000") if err != nil { log.Fatalf("failed to listen: %v", err) } // create grpc server s := grpc.NewServer() pb.RegisterDaprClientServer(s, &server{}) fmt.Println("Client starting...") // and start... if err := s.Serve(lis); err != nil { log.Fatalf("failed to serve: %v", err) } } // Sample method to invoke func (s *server) MyMethod() string { return "Hi there!" } // This method gets invoked when a remote service has called the app through Dapr // The payload carries a Method to identify the method, a set of metadata properties and an optional payload func (s *server) OnInvoke(ctx context.Context, in *pb.InvokeEnvelope) (*any.Any, error) { var response string fmt.Println(fmt.Sprintf("Got invoked with: %s", string(in.Data.Value))) switch in.Method { case "MyMethod": response = s.MyMethod() } return &any.Any{ Value: []byte(response), }, nil } // Dapr will call this method to get the list of topics the app wants to subscribe to. In this example, we are telling Dapr // To subscribe to a topic named TopicA func (s *server) GetTopicSubscriptions(ctx context.Context, in *empty.Empty) (*pb.GetTopicSubscriptionsEnvelope, error) { return &pb.GetTopicSubscriptionsEnvelope{ Topics: []string{"TopicA"}, }, nil } // Dapper will call this method to get the list of bindings the app will get invoked by. In this example, we are telling Dapr // To invoke our app with a binding named storage func (s *server) GetBindingsSubscriptions(ctx context.Context, in *empty.Empty) (*pb.GetBindingsSubscriptionsEnvelope, error) { return &pb.GetBindingsSubscriptionsEnvelope{ Bindings: []string{"storage"}, }, nil } // This method gets invoked every time a new event is fired from a registerd binding. The message carries the binding name, a payload and optional metadata func (s *server) OnBindingEvent(ctx context.Context, in *pb.BindingEventEnvelope) (*pb.BindingResponseEnvelope, error) { fmt.Println("Invoked from binding") return &pb.BindingResponseEnvelope{}, nil } // This method is fired whenever a message has been published to a topic that has been subscribed. Dapr sends published messages in a CloudEvents 0.3 envelope. func (s *server) OnTopicEvent(ctx context.Context, in *pb.CloudEventEnvelope) (*empty.Empty, error) { fmt.Println("Topic message arrived") return &empty.Empty{}, nil }
使用 Dapr 命令启动 StorageService
dapr run --app-id client --protocol grpc --app-port 4000 go run main.go
注意:
- Dapr 使用 App 端口号应与服务端口号相同,使用 --protocal grpc 指定通讯协议为 grpc 。此外,OnInvoke 中的 switch 方法用于调用者路由。
使用 ASP.NET Core
创建 StorageService
- 使用 NuGet 获取程序管理包控制台安装以下包
- Dapr.AspNetCore
- Dapr.Client.Grpc
- Grpc.AspNetCore
- Grpc.Net.Client
- Grpc.Tools
Startup.cs
文件中修改代码如下:///
/// This method gets called by the runtime. Use this method to add services to the container. /// /// Services. public void ConfigureServices(IServiceCollection services) { services.AddControllers().AddDapr(); services.AddDbContextPool(options => { options.UseMySql(Configuration.GetConnectionString("MysqlConnection")); }); } ///
/// This method gets called by the runtime. Use this method to configure the HTTP request pipeline. /// /// app. /// env. public void Configure(IApplicationBuilder app, IWebHostEnvironment env) { if (env.IsDevelopment()) { app.UseDeveloperExceptionPage(); } app.UseRouting(); app.UseCloudEvents(); app.UseAuthorization(); app.UseEndpoints(endpoints => { endpoints.MapSubscribeHandler(); endpoints.MapControllers(); }); }添加
StorageController.cs
文件,内容如下using System; using System.Linq; using System.Threading.Tasks; using Dapr.Client.Grpc; using Google.Protobuf; using Grpc.Net.Client; using Microsoft.AspNetCore.Mvc; using StorageService.Api.Entities; namespace StorageService.Api.Controllers { [ApiController] public class StorageController : ControllerBase { private readonly StorageContext _storageContext; public StorageController(StorageContext storageContext) { _storageContext = storageContext; } ///
/// 初始化仓库. /// ///是否成功. [HttpGet("InitialStorage")] public async TaskInitialStorage() { string defaultPort = Environment.GetEnvironmentVariable("DAPR_GRPC_PORT") ?? "54681"; // Set correct switch to make insecure gRPC service calls. This switch must be set before creating the GrpcChannel. AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true); // Create Client string daprUri = $"http://127.0.0.1:{defaultPort}"; GrpcChannel channel = GrpcChannel.ForAddress(daprUri); var client = new Dapr.Client.Grpc.Dapr.DaprClient(channel); Console.WriteLine(daprUri); InvokeServiceResponseEnvelope result = await client.InvokeServiceAsync(new InvokeServiceEnvelope { Method = "MyMethod", Id = "client", Data = new Google.Protobuf.WellKnownTypes.Any { Value = ByteString.CopyFromUtf8("Hello ProductService") } }); Console.WriteLine("this is call result:" + result.Data.Value.ToStringUtf8()); //var productResult = result.Data.Unpack (); //Console.WriteLine("this is call result:" + productResult.Results.FirstOrDefault()); return true; } /// /// 修改库存 /// /// ///[HttpPut("Reduce")] public bool Reduce(Storage storage) { Storage storageFromDb = _storageContext.Storage.FirstOrDefault(q => q.ProductID.Equals(storage.ProductID)); if (storageFromDb == null) { return false; } if (storageFromDb.Amount <= storage.Amount) { return false; } storageFromDb.Amount -= storage.Amount; return true; } } } 使用 Dapr cli 启用 StorageService 服务
dapr run --app-id storageService --app-port 5003 dotnet run
使用 curl 命令访问 StorageService InitialStorage 方法
curl -X GET http://localhost:56349/v1.0/invoke/storageService/method/InitialStorage
输入
true
其中打印信息为:
this is call result:Hi there!
注意:
- Dapr 使用 App 端口号应与服务端口号相同,例如:
ASP.Net Core
服务端口号为5003,则在使用 Dapr 托管应用程序时的端口号也应使用 5003,在 Client.InvokeServiceAsync 中的 Id 指被调用方的 App-Id ,Method 指被调用方方法名称。参考 Go Server 中 OnInvoke 方法的 Switch 。
源码地址