Asp .Net Core 系列：集成 Ocelot+Consul实现网关、服务注册、服务发现

什么是Ocelot?

Ocelot是一个开源的ASP.NET Core微服务网关，它提供了API网关所需的所有功能，如路由、认证、限流、监控等。

Ocelot是一个简单、灵活且功能强大的API网关，它可以与现有的服务集成，并帮助您保护、监控和扩展您的微服务。

以下是Ocelot的一些主要功能：

1. 路由管理：Ocelot允许您定义路由规则，将请求路由到正确的微服务。
2. 认证和授权：Ocelot支持多种认证机制，如JWT、OAuth等，并允许您定义访问控制策略，确保只有授权的用户才能访问特定的API。
3. 限流和速率限制：Ocelot提供了一些内置的限流和速率限制功能，以确保您的服务不会受到过度的请求压力。
4. 监控和日志：Ocelot可以收集和显示各种度量指标，帮助您了解您的服务的性能和行为。此外，它还可以将日志记录到各种日志源，以便您进行分析和故障排除。
5. 集成：Ocelot可以与现有的服务集成，包括Kubernetes、Consul等。
6. 易于扩展：Ocelot的设计使其易于扩展，您可以编写自己的中间件来处理特定的逻辑，例如修改请求或响应、添加自定义的认证机制等。
7. 可扩展的配置：Ocelot使用JSON配置文件进行配置，这意味着您可以轻松地根据需要进行配置更改，而无需重新编译代码。

总之，Ocelot是一个功能强大且易于使用的API网关，可以帮助您保护、监控和扩展您的微服务。

Asp .Net Core 集成 Ocelot

要在ASP.NET Core中集成Ocelot，您可以按照以下步骤进行操作：

1. 安装Ocelot NuGet包：
   在您的ASP.NET Core项目中，打开终端或NuGet包管理器控制台，并运行以下命令来安装Ocelot的NuGet包：

dotnet add package Ocelot

2. 添加Ocelot配置文件：

{  
  "Routes": [ //这里注意一下版本（旧版本用ReRoutes）
    {
      "DownstreamPathTemplate": "/api/{controller}", //下游路径模板
      "DownstreamScheme": "http", //下游方案
      //"DownstreamHostAndPorts": [
      //  {
      //    "Host": "localhost",
      //    "Port": "5014"
      //  }
      //], //下游主机和端口
      "UpstreamPathTemplate": "/api/product/{controller}", //上游路径模板
      "UpstreamHttpMethod": [], //上游请求方法,可以设置特定的 HTTP 方法列表或设置空列表以允许其中任何方法
      "ServiceName": "api-product-service", //请求服务名称
      "LoadBalancerOptions": {
        "Type": "LeastConnection" //负载均衡算法：目前 Ocelot 有RoundRobin 和LeastConnection算法
      }
    }
  ],
  "GlobalConfiguration": {
    "BaseUrl": "http://localhost:5015", //进行标头查找和替换以及某些管理配置
    "ServiceDiscoveryProvider": {
      "Scheme": "http",
      "Host": "127.0.0.1", //你的Consul的ip地址
      "Port": 8500, //你的Consul的端口
      "Type": "Consul" //类型
      //"ConfigurationKey": "Consul" //指定配置键，键入您的配置
    }
  }
}

3. 配置Ocelot服务：

builder.Services.AddOcelot();

在Configure方法中配置请求管道并添加Ocelot中间件：

app.UseOcelot().Wait();

Ocelot 集成 Consul

要将Ocelot集成到Consul中，您可以按照以下步骤进行操作：

1. 安装依赖项：
   在您的ASP.NET Core项目中，安装Ocelot和Consul的NuGet包。您可以使用以下命令来安装这些包：

dotnet add package Ocelot.Provider.Consul

1. 配置Ocelot：
   在Ocelot的配置中，您需要指定Consul作为服务发现和配置的提供者。在Ocelot的配置文件（例如appsettings.json）中，添加以下内容：

{  
  "GlobalConfiguration": {
    "BaseUrl": "http://localhost:5015", //进行标头查找和替换以及某些管理配置
    "ServiceDiscoveryProvider": {
      "Scheme": "http",
      "Host": "127.0.0.1", //你的Consul的ip地址
      "Port": 8500, //你的Consul的端口
      "Type": "Consul" //类型
      //"ConfigurationKey": "Consul" //指定配置键，键入您的配置
    }
  } 
}

确保将ConsulHost和ConsulPort设置为Consul服务器的正确地址和端口。

3. 启动Ocelot：
   在您的ASP.NET Core应用程序中启动Ocelot。您可以在Startup.cs文件中添加以下代码：

builder.Services.AddOcelot().AddConsul(); 

全部代码

Consul相关代码

namespace MCode.Common.Extensions.Consul
{
    public class ConsulOptions
    {
        /// <summary>
        /// 当前应用IP
        /// </summary>
        public string IP { get; set; }

        /// <summary>
        /// 当前应用端口
        /// </summary>
        public int Port { get; set; }

        /// <summary>
        /// 当前服务名称
        /// </summary>
        public string ServiceName { get; set; }

        /// <summary>
        /// Consul集群IP
        /// </summary>
        public string ConsulIP { get; set; }

        /// <summary>
        /// Consul集群端口
        /// </summary>
        public int ConsulPort { get; set; }

        /// <summary>
        /// 权重
        /// </summary>
        public int? Weight { get; set; }
    }
}

using Consul.AspNetCore;
using Consul;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Configuration;
using Microsoft.AspNetCore.Builder;

namespace MCode.Common.Extensions.Consul
{
    public static class ConsulServiceExtensions
    {
        /// <summary>
        /// 向容器中添加Consul必要的依赖注入
        /// </summary>
        /// <param name="services"></param>
        /// <param name="configuration"></param>
        /// <returns></returns>
        public static IServiceCollection AddMCodeConsul(this IServiceCollection services)
        {
            var configuration = services.BuildServiceProvider().GetRequiredService<IConfiguration>();
            // 配置consul服务注册信息
            var consulOptions = configuration.GetSection("Consul").Get<ConsulOptions>();
            // 通过consul提供的注入方式注册consulClient
            services.AddConsul(options => options.Address = new Uri($"http://{consulOptions.ConsulIP}:{consulOptions.ConsulPort}"));

            // 通过consul提供的注入方式进行服务注册
            var httpCheck = new AgentServiceCheck()
            {
                DeregisterCriticalServiceAfter = TimeSpan.FromSeconds(5),//服务启动多久后注册
                Interval = TimeSpan.FromSeconds(10),//健康检查时间间隔，或者称为心跳间隔
                HTTP = $"http://{consulOptions.IP}:{consulOptions.Port}/health",//健康检查地址
                Timeout = TimeSpan.FromSeconds(10)
            };

            // Register service with consul
            services.AddConsulServiceRegistration(options =>
            {
                options.Checks = new[] { httpCheck };
                options.ID = Guid.NewGuid().ToString();
                options.Name = consulOptions.ServiceName;
                options.Address = consulOptions.IP;
                options.Port = consulOptions.Port;
                options.Meta = new Dictionary<string, string>() { { "Weight", consulOptions.Weight.HasValue ? consulOptions.Weight.Value.ToString() : "1" } };
                options.Tags = new[] { $"urlprefix-/{consulOptions.ServiceName}" }; //添加
            });

            return services;
        }

        /// <summary>
        /// 配置Consul检查服务
        /// </summary>
        /// <param name="app"></param>
        /// <returns></returns>
        public static IApplicationBuilder UseConsulCheckService(this IApplicationBuilder app)
        {
            app.Map("/health", app =>
            {
                app.Run(async context =>
                {
                    await Task.Run(() => context.Response.StatusCode = 200);
                });
            });

            return app;
        }
    }
}

Cors

using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.DependencyInjection;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MCode.Common.Extensions.Cors
{
    public static class CorsServiceExtensions
    {
        private readonly static string PolicyName = "MCodeCors";

        /// <summary>
        /// 添加跨域
        /// </summary>
        /// <param name="services">服务集合</param>
        /// <returns></returns>
        public static IServiceCollection AddMCodeCors(this IServiceCollection services)
        {
            if (services == null) throw new ArgumentNullException(nameof(services));
            //origin microsoft.aspnetcore.cors      
            return services.AddCors(options =>
            {
                options.AddPolicy(PolicyName, policy =>
                {
                    policy.SetIsOriginAllowed(_ => true).AllowAnyMethod().AllowAnyHeader().AllowCredentials();
                });
            });
        }
        /// <summary>
        /// 使用跨域
        /// </summary>
        /// <param name="app">应用程序建造者</param>
        /// <returns></returns>
        public static IApplicationBuilder UseMCodeCors(this IApplicationBuilder app)
        {
            return app.UseCors(PolicyName);
        }
    }
}

Swagger

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MCode.Common.Extensions.Swagger
{
    /// <summary>
    /// 网关Swagger配置
    /// </summary>
    public class OcelotSwaggerOptions
    {
        public List<SwaggerEndPoint> SwaggerEndPoints { get; set; }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MCode.Common.Extensions.Swagger
{
    /// <summary>
    /// 网关Swagger配置
    /// </summary>
    public class OcelotSwaggerOptions
    {
        public List<SwaggerEndPoint> SwaggerEndPoints { get; set; }
    }
}

using Microsoft.OpenApi.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MCode.Common.Extensions.Swagger
{
    /// <summary>
    /// Swagger配置
    /// </summary>
    public class SwaggerOptions
    {
        /// <summary>
        /// 服务名称
        /// </summary>
        public string ServiceName { get; set; }

        /// <summary>
        /// API信息
        /// </summary>
        public OpenApiInfo ApiInfo { get; set; }

        /// <summary>
        /// Xml注释文件
        /// </summary>
        public string[] XmlCommentFiles { get; set; }

        /// <summary>
        /// 构造函数
        /// </summary>
        /// <param name="serviceName">服务名称</param>
        /// <param name="apiInfo">API信息</param>
        /// <param name="xmlCommentFiles">Xml注释文件</param>
        public SwaggerOptions(string serviceName, OpenApiInfo apiInfo, string[] xmlCommentFiles = null)
        {
            ServiceName = !string.IsNullOrWhiteSpace(serviceName) ? serviceName : throw new ArgumentException("serviceName parameter not config.");
            ApiInfo = apiInfo;
            XmlCommentFiles = xmlCommentFiles;
        }
    }
}

using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.OpenApi.Models;

namespace MCode.Common.Extensions.Swagger
{
    /// <summary>
    /// Swagger 服务扩展
    /// </summary>
    public static class SwaggerServiceExtensions
    {
        /// <summary>
        /// 添加 Swagger 服务
        /// </summary>
        /// <param name="services"></param>
        /// <param name="swaggerOptions"></param>
        /// <returns></returns>
        public static IServiceCollection AddMCodeSwagger(this IServiceCollection services, SwaggerOptions swaggerOptions)
        {
            services.AddSingleton(swaggerOptions);

            SwaggerGenServiceCollectionExtensions.AddSwaggerGen(services, c =>
            {
                c.SwaggerDoc(swaggerOptions.ServiceName, swaggerOptions.ApiInfo);

                if (swaggerOptions.XmlCommentFiles != null)
                {
                    foreach (string xmlCommentFile in swaggerOptions.XmlCommentFiles)
                    {
                        string str = Path.Combine(AppContext.BaseDirectory, xmlCommentFile);
                        if (File.Exists(str)) c.IncludeXmlComments(str, true);
                    }
                }

                SwaggerGenOptionsExtensions.CustomSchemaIds(c, x => x.FullName);

                c.AddSecurityDefinition("bearerAuth", new OpenApiSecurityScheme
                {
                    Type = SecuritySchemeType.Http,
                    Scheme = "bearer",
                    BearerFormat = "JWT",
                    Description = "请输入 bearer 认证"
                });


                c.AddSecurityRequirement(new OpenApiSecurityRequirement
                                              {
                                                  {
                                                      new OpenApiSecurityScheme
                                                      {
                                                          Reference = new OpenApiReference { Type = ReferenceType.SecurityScheme, Id = "bearerAuth" }
                                                      },
                                                      new string[] {}
                                                  }
                                              });
            });

            return services;
        }

        /// <summary>
        /// 使用 Swagger UI
        /// </summary>
        /// <param name="app"></param>
        /// <returns></returns>
        public static IApplicationBuilder UseMCodeSwagger(this IApplicationBuilder app)
        {
            string serviceName = app.ApplicationServices.GetRequiredService<SwaggerOptions>().ServiceName;

            SwaggerUIBuilderExtensions.UseSwaggerUI(SwaggerBuilderExtensions.UseSwagger(app), c =>
            {
                c.SwaggerEndpoint("/swagger/" + serviceName + "/swagger.json", serviceName);
            });
            return app;
        }


        public static IServiceCollection AddMCodeOcelotSwagger(this IServiceCollection services, OcelotSwaggerOptions ocelotSwaggerOptions)
        {
            services.AddSingleton(ocelotSwaggerOptions);
            SwaggerGenServiceCollectionExtensions.AddSwaggerGen(services);
            return services;
        }

        public static IApplicationBuilder UseMCodeOcelotSwagger(this IApplicationBuilder app)
        {
            OcelotSwaggerOptions ocelotSwaggerOptions = app.ApplicationServices.GetService<OcelotSwaggerOptions>();

            if (ocelotSwaggerOptions == null || ocelotSwaggerOptions.SwaggerEndPoints == null)
            {
                return app;
            }

            SwaggerUIBuilderExtensions.UseSwaggerUI(SwaggerBuilderExtensions.UseSwagger(app), c =>
            {
                foreach (SwaggerEndPoint swaggerEndPoint in ocelotSwaggerOptions.SwaggerEndPoints)
                {
                    c.SwaggerEndpoint(swaggerEndPoint.Url, swaggerEndPoint.Name);
                }
            });
            return app;
        }
    }
}

MCode.ApiGateway.Program

using MCode.Common.Extensions.Swagger;
using MCode.Common.Extensions.Consul;
using MCode.Common.Extensions.Cors;
using Ocelot.DependencyInjection;
using Ocelot.Middleware;
using Ocelot.Provider.Consul;
using Microsoft.AspNetCore.Hosting;

var builder = WebApplication.CreateBuilder(args);

builder.WebHost.UseUrls(builder.Configuration.GetValue<string>("Url") ?? "");

//builder.Configuration.SetBasePath(Directory.GetCurrentDirectory()).AddJsonFile("ocelot.json", false, true);

// Add services to the container.
builder.Services.AddMCodeConsul();

builder.Services.AddMCodeCors();

builder.Services.AddMCodeOcelotSwagger(new OcelotSwaggerOptions { SwaggerEndPoints = new List<SwaggerEndPoint> { new SwaggerEndPoint { Name = "api-product-service", Url= "http://localhost:5014/swagger/api-product-service/swagger.json" } } });

builder.Services.AddOcelot().AddConsul();

builder.Services.AddControllers();

var app = builder.Build();

app.UseMCodeCors();

app.UseMCodeOcelotSwagger();

app.UseConsulCheckService();

// Configure the HTTP request pipeline.

app.UseAuthorization();

app.UseOcelot().Wait();

app.Run();

appsettings.json

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  },
  "Routes": [ //这里注意一下版本（旧版本用ReRoutes）
    {
      "DownstreamPathTemplate": "/api/{controller}", //下游路径模板
      "DownstreamScheme": "http", //下游方案
      //"DownstreamHostAndPorts": [
      //  {
      //    "Host": "localhost",
      //    "Port": "5014"
      //  }
      //], //下游主机和端口
      "UpstreamPathTemplate": "/api/product/{controller}", //上游路径模板
      "UpstreamHttpMethod": [], //上游请求方法,可以设置特定的 HTTP 方法列表或设置空列表以允许其中任何方法
      "ServiceName": "api-product-service", //请求服务名称
      "LoadBalancerOptions": {
        "Type": "LeastConnection" //负载均衡算法：目前 Ocelot 有RoundRobin 和LeastConnection算法
      }
    }
  ],
  "GlobalConfiguration": {
    "BaseUrl": "http://localhost:5015", //进行标头查找和替换以及某些管理配置
    "ServiceDiscoveryProvider": {
      "Scheme": "http",
      "Host": "127.0.0.1", //你的Consul的ip地址
      "Port": 8500, //你的Consul的端口
      "Type": "Consul" //类型
      //"ConfigurationKey": "Consul" //指定配置键，键入您的配置
    }
  },
  "Url": "http://localhost:5015",
  "Consul": {
    "ConsulIP": "127.0.0.1",
    "ConsulPort": "8500",
    "ServiceName": "api-gateway",
    "Ip": "localhost",
    "Port": "5015",
    "Weight": 1
  },
  "AllowedHosts": "*"
}

MCode.Product.Api.Program

using MCode.Product.Api;
using MCode.Common.Extensions.Consul;
using MCode.Common.Extensions.Cors;
using MCode.Common.Extensions.Swagger;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.WebHost.UseUrls(builder.Configuration.GetValue<string>("Url") ?? "");

builder.Services.AddControllers();

builder.Services.AddMCodeConsul();

builder.Services.AddMCodeCors();

builder.Services.AddMCodeSwagger(new SwaggerOptions("api-product-service", new Microsoft.OpenApi.Models.OpenApiInfo { Title = "产品服务" }, new string[] { "MCode.Product.Api.xml" }));


var app = builder.Build();

app.UseAuthorization();


app.UseMCodeCors();

app.UseMCodeSwagger();

app.UseConsulCheckService();


app.MapControllers();

app.Run();

appsettings.json

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  },
  "AllowedHosts": "*",
  "Url": "http://localhost:5014",
  "Consul": {
    "ConsulIP": "127.0.0.1",
    "ConsulPort": "8500",
    "ServiceName": "api-product-service",
    "Ip": "localhost",
    "Port": "5014",
    "Weight": 1
  }
}

效果