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項目地址

• 教程作者：
• 教程地址：

• 代碼倉庫地址：

• 所用到的框架和插件：

dbt 
airflow

一、異常處理

1.1 自定異常

• BadRequestException
• InternalServerException
• NotFoundException

1.2 自定義異常處理中間件

• 異常處理中間件

public class CustomExceptionHandler(ILogger<CustomExceptionHandler> logger): IExceptionHandler
{public async ValueTask<bool> TryHandleAsync(HttpContext context, Exception exception, CancellationToken cancellationToken){logger.LogError("Error Message: {exceptionMessage}, Time of occurrence {time}",exception.Message, DateTime.UtcNow);(string Detail, string Title, int StatusCode) details = exception switch{InternalServerException =>(exception.Message,exception.GetType().Name,context.Response.StatusCode = StatusCodes.Status500InternalServerError),ValidationException =>(exception.Message,exception.GetType().Name,context.Response.StatusCode = StatusCodes.Status400BadRequest),BadRequestException =>(exception.Message,exception.GetType().Name,context.Response.StatusCode = StatusCodes.Status400BadRequest),NotFoundException =>(exception.Message,exception.GetType().Name,context.Response.StatusCode = StatusCodes.Status404NotFound),_ =>(exception.Message,exception.GetType().Name,context.Response.StatusCode = StatusCodes.Status500InternalServerError)};var problemDetails = new ProblemDetails{Title = details.Title,Detail = details.Detail,Status = details.StatusCode,Instance = context.Request.Path};problemDetails.Extensions.Add("traceId", context.TraceIdentifier);if (exception is ValidationException validationException){problemDetails.Extensions.Add("ValidationErrors", validationException.Errors);}await context.Response.WriteAsJsonAsync(problemDetails, cancellationToken: cancellationToken);return true;}
}

• 返回例

{"title": "ValidationException","detail": "參數驗證失敗","status": 400,"instance": "/api/products","traceId": "00-9d4a78437e-abc123def456-01","ValidationErrors": [{"PropertyName": "Name","ErrorMessage": "Name 不能為空"},{"PropertyName": "Age","ErrorMessage": "Age 必須大于 0"}]
}

1.3 注冊中間件

• 給所有微服務注冊
  

二、grpc服務

土耳其146

• 這里主要實現了discount模塊的grpc，我們可以通過api進行增刪改查

2.1 創建protos

1. 打折的protos

• 定義請求和返回值

syntax = "proto3";option csharp_namespace = "Discount.Grpc";package discount;// The discount service definition.
service DiscountProtoService {// Discount CRUD Operationsrpc GetDiscount (GetDiscountRequest) returns (CouponModel);rpc CreateDiscount (CreateDiscountRequest) returns (CouponModel);rpc UpdateDiscount (UpdateDiscountRequest) returns (CouponModel);rpc DeleteDiscount (DeleteDiscountRequest) returns (DeleteDiscountResponse);
}message GetDiscountRequest {string productName = 1;
}message CouponModel {int32 id = 1;string productName = 2;string description = 3;int32 amount = 4;
}message CreateDiscountRequest {CouponModel coupon = 1;
}message UpdateDiscountRequest {CouponModel coupon = 1;
}message DeleteDiscountRequest {string productName = 1;
}message DeleteDiscountResponse {bool success = 1;
}

2. 設置grpc server

• 設置grpc服務
  
• 設置成功后，可以在模塊的包管理器看到

3. program配置服務

4. docker-compose

2.2 CRUD

1. 查詢

2.3 測試

1. 發起查詢請求

三、grpc服務消費

土167

• Basket.Api 服務調用Discount.Grpc服務

3.1 創建client

• Basket服務要去調用Discount服務，所以Basket是 Client， Discount是 service

1. 添加服務

2. 選擇需要添加的服務類型

3. 選擇服務路徑

4. 添加成功后

• 添加成功后，basket模塊會有Protos文件夾
  

5. Program里添加Client服務

• 在Basket模塊的Program里添加
  

6. appSettings里添加grpc服務地址

• 添加Grpc的服務地址
  

3.2 grpc通訊

1. 在StoreBasketCommandHandler使用

• 在StoreBasketCommandHandler里進行折扣服務的扣減