Ocelot集成Consul实现api网关与服务发现

前言

没看dotnet微服务之API网关Ocelot的请先看，这篇文章接上面文章

安装consul

#自定义网络，自定义网络可以指定容器IP，这样服务器重启consul集群也可以正常运行。 docker network create --driver bridge --subnet=172.21.0.0/16 --gateway=172.21.0.16 adnc_consul  docker run -d -p 8500:8500 -p 8600:8600 -p 8301:8301 --restart=always --network=adnc_consul --ip 172.21.0.1 --privileged=true --name=consul_server_1  --name consul consul:1.15.4 agent -server -bootstrap -ui -node=consul_server_1 -client='0.0.0.0' 

在GoodApi项目中修改Program.cs

先要添加Consul包

再添加Consul注册于注销等相关代码

using Consul; using System.Linq; using System.Net; using System.Net.Sockets;  // 创建Consul客户端 var consulAddress = "http://10.75.174.43:8500";// Environment.GetEnvironmentVariable("CONSUL_ADDRESS"); //10.75.174.43 var consulUri = new Uri(consulAddress); var client = new ConsulClient(config => {     config.Address = consulUri; });  // 配置服务的健康检查 var check = new AgentServiceCheck() {     HTTP = $"http://{GetLocalIpAddress("InterNetwork").FirstOrDefault()}:8080/health", // 健康检查地址     Interval = TimeSpan.FromSeconds(10) // 检查间隔 }; var serviceId = "goodapi-1"; // 要注销的服务的ID // 注册一个服务 var registration = new AgentServiceRegistration() {     ID = serviceId,     Name = "goodapi",     Address = GetLocalIpAddress("InterNetwork").FirstOrDefault(),     Port = 8080,     Check = check };  await client.Agent.ServiceDeregister(serviceId); client.Agent.ServiceRegister(registration);  var builder = WebApplication.CreateBuilder(args);  // Add services to the container.  builder.Services.AddControllers(); // Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle builder.Services.AddEndpointsApiExplorer(); builder.Services.AddSwaggerGen();  var app = builder.Build();  // Configure the HTTP request pipeline. //if (app.Environment.IsDevelopment()) {     app.UseSwagger();     app.UseSwaggerUI(); }  app.MapControllers();  app.MapGet("/health", async context => {     context.Response.StatusCode = 200;     await context.Response.WriteAsync("health"); });  app.Run();  // 注销服务  await client.Agent.ServiceDeregister(serviceId);  List<string> GetLocalIpAddress(string netType) {     string hostName = Dns.GetHostName();     IPAddress[] addresses = Dns.GetHostAddresses(hostName);      var IPList = new List<string>();     if (netType == string.Empty)     {         for (int i = 0; i < addresses.Length; i++)         {             IPList.Add(addresses[i].ToString());         }     }     else     {         //AddressFamily.InterNetwork = IPv4,         //AddressFamily.InterNetworkV6= IPv6         for (int i = 0; i < addresses.Length; i++)         {             if (addresses[i].AddressFamily.ToString() == netType)             {                 IPList.Add(addresses[i].ToString());             }         }     }     return IPList; } 

加Dockerfile文件

#使用asp.net 6作为基础镜像，起一个别名为base FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS base #设置容器的工作目录为/app WORKDIR /app #COPY 文件 COPY . /app ENV ASPNETCORE_ENVIRONMENT Production  #设置时区为东八区 ENV TZ Asia/Shanghai #启动服务 ENTRYPOINT ["dotnet", "GoodApi.dll"] 

# 运行goodapi项目 docker stop goodapi docker rm -f goodapi docker build -t goodapi . docker run --name=goodapi -d -p 8080:8080 --network=adnc_consul goodapi 

在OcelotGA中加consul配置与代码

加包Consul，Ocelot.Provider.Consul

改ocelot.json配置

{   "Routes": [     {       "UseServiceDiscovery": true,       "UpstreamPathTemplate": "/good/{everything}",       "UpstreamHttpMethod": [ "Get" ],       "DownstreamPathTemplate": "/{everything}",       "DownstreamScheme": "http",       "ServiceName": "goodapi",       "LoadBalancerOptions": {         "Type": "LeastConnection"       }     },     {       "UseServiceDiscovery": true,       "UpstreamPathTemplate": "/order/{everything}",       "UpstreamHttpMethod": [ "Get" ],       "DownstreamPathTemplate": "/{everything}",       "DownstreamScheme": "http",       "ServiceName": "orderapi",       "LoadBalancerOptions": {         "Type": "LeastConnection"       }     }   ],   "GlobalConfiguration": {     "BaseUrl": "http://gw.wxy.ink",     "ServiceDiscoveryProvider": {       "Scheme": "http",       "Host": "10.75.174.43", // 这里是您Consul的地址       "Port": 8500, // Consul的端口       "Type": "Consul"     }   } } 

修改Program.cs

using Microsoft.AspNetCore.Builder; using Microsoft.Extensions.DependencyInjection; using Ocelot.DependencyInjection; using Ocelot.Middleware; using Ocelot.Provider.Consul; using System; using System.Collections.Generic; using System.Net;  using Consul; using OcelotGA;  // 创建Consul客户端 var consulAddress = "http://10.75.174.43:8500";// Environment.GetEnvironmentVariable("CONSUL_ADDRESS"); //10.75.174.43 var consulUri = new Uri(consulAddress); var client = new ConsulClient(config => {     config.Address = consulUri; });  // 配置服务的健康检查 var check = new AgentServiceCheck() {     HTTP = $"http://{GetLocalIpAddress("InterNetwork").FirstOrDefault()}:8080/health", // 健康检查地址     Interval = TimeSpan.FromSeconds(10) // 检查间隔 }; var serviceId = "gw-1"; // 要注销的服务的ID // 注册一个服务 var registration = new AgentServiceRegistration() {     ID = serviceId,     Name = "gw",     Address = GetLocalIpAddress("InterNetwork").FirstOrDefault(),     Port = 8080,     //Check = check };  await client.Agent.ServiceDeregister(serviceId); client.Agent.ServiceRegister(registration);  var builder = WebApplication.CreateBuilder(args);  builder.Configuration.AddJsonFile("ocelot.json", optional: false, reloadOnChange: true);  builder.Services.AddOcelot().AddConsul<MyConsulServiceBuilder>(); //这里要注意MyConsulServiceBuilder  var app = builder.Build();  app.UseOcelot().Wait();  app.UseRouting();  app.MapGet("/Health", async context => {     context.Response.StatusCode = 200;     await context.Response.WriteAsync("Health"); });  app.Run();  // 注销服务  await client.Agent.ServiceDeregister(serviceId);  List<string> GetLocalIpAddress(string netType) {     string hostName = Dns.GetHostName();     IPAddress[] addresses = Dns.GetHostAddresses(hostName);      var IPList = new List<string>();     if (netType == string.Empty)     {         for (int i = 0; i < addresses.Length; i++)         {             IPList.Add(addresses[i].ToString());         }     }     else     {         //AddressFamily.InterNetwork = IPv4,         //AddressFamily.InterNetworkV6= IPv6         for (int i = 0; i < addresses.Length; i++)         {             if (addresses[i].AddressFamily.ToString() == netType)             {                 IPList.Add(addresses[i].ToString());             }         }     }     return IPList; } 

添加MyConsulServiceBuilder.cs

using Consul; using Ocelot.Logging; using Ocelot.Provider.Consul; using Ocelot.Provider.Consul.Interfaces;  namespace OcelotGA {     public class MyConsulServiceBuilder : DefaultConsulServiceBuilder     {         public MyConsulServiceBuilder(IHttpContextAccessor contextAccessor, IConsulClientFactory clientFactory, IOcelotLoggerFactory loggerFactory)             : base(contextAccessor, clientFactory, loggerFactory) { }          // I want to use the agent service IP address as the downstream hostname         protected override string GetDownstreamHost(ServiceEntry entry, Node node)             => entry.Service.Address;     } } 

运行网关项目

我们访问gw.wxy.ink/good/health

爬坑记录

Program.cs中的

builder.Services.AddOcelot().AddConsul<MyConsulServiceBuilder>(); //这里要注意MyConsulServiceBuilder 若为 builder.Services.AddOcelot().AddConsul(); 

则会出现下面问题

服务解析出来是node的名称，而非服务的IP

解决方法：Service Discovery — Ocelot Gateway 23.4 documentation

就是说默认的DefaultConsulServiceBuilder会这样处理

protected virtual string GetDownstreamHost(ServiceEntry entry, Node node)     => node != null ? node.Name : entry.Service.Address; 

而我们需要的是

protected override string GetDownstreamHost(ServiceEntry entry, Node node)         => entry.Service.Address; 

作者

吴晓阳（手机：13736969112微信同号）