实现效果 通过consul服务，可以找找任意服务(包括自己)。 现在已实现的负载均衡器有
1.随机负载均衡器
2.轮回负载均衡器
3.单例服务负载均衡器（直接返回第一个）
4.其他方式 陆续添加
使用方式
Nuget安装GreenWhale.Extensions.Consuls 依次添加Consul，并配置Consul。
在这里你需要指定Consul服务器的地址，本机的地址，ID，名称等。
然后UseConsulBuilder().UseConsul();
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
services.AddConsul().Configure((s)=>
{
s.Id = Guid.NewGuid().ToString();
s.Name = this.GetType().Name;
s.ServerAddress = "http://localhost:8500";
s.HealthCheckPath = "/health";
s.LocalServer = new GreenWhale.Extensions.Consuls.LocalServer//要想使用环境注入的URLS，则不可使用iisexpress；
{
UseEnvironment = true,
};
});
services.AddPolly().Configure(s=>
{
s.TimeOutTimeSpan = TimeSpan.FromSeconds(5);
s.RetryCount = 2;
s.FallBackRespond = new FallBackRespondMessage
{
Content = "服务已经降级",
StatusCode = System.Net.HttpStatusCode.NotFound
};
s.CircuitBreaker = new CircuitBreakerRespondMessage
{
Content = "服务发生熔断",
RecoveryTimeSpan = TimeSpan.FromSeconds(20),
ToCloseCount = 2
};
});
services.AddControllers();
services.AddHealthChecks();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseHttpsRedirection();
app.UseRouting();
app.UseAuthorization();
app.UseConsulBuilder().UseConsul();
app.UsePollyBuilder().UsePollyDefault();
app.UseHealthChecks(new Microsoft.AspNetCore.Http.PathString("/health"));
app.UseEndpoints(endpoints =>
{
endpoints.MapControllers();
});
}
}在要发现的控制器中直接IConsulDiscoveryService注入。如果觉得默认方法不够用，扩展IConsulDiscoveryService 即可。
[ApiController]
[Route("[controller]")]
public class WeatherForecastController : ControllerBase
{
private readonly IConsulDiscoveryService consulDiscoveryService;
public WeatherForecastController(IConsulDiscoveryService consulDiscoveryService)
{
this.consulDiscoveryService = consulDiscoveryService;
}
[HttpGet]
public async Task<Uri> Get()
{
var services= await consulDiscoveryService.Find("Startup");
_logger.LogInformation("服务的URI已查找到");
return services.BaseAddress;
}
}如果你使用IIS或者IISExpress则你必须手动指定本机地址和端口，如果你使用非IIS方式，则直接指定UseEnviroment为True即可。
如果要用配置文件，则在对应的配置文件中编写一样的名称的键值对就可以了。
/// <summary>
/// Consul节点信息
/// </summary>
public class NodeInfo
{
/// <summary>
/// 服务ID
/// </summary>
public string Id { get; set; }
/// <summary>
/// 服务名称
/// </summary>
public string Name { get; set; }
/// <summary>
/// 附加信息
/// </summary>
public string[] Tags { get; set; }
/// <summary>
/// 本机服务器
/// </summary>
public LocalServer LocalServer { get; set; }
/// <summary>
/// Consul服务器地址
/// </summary>
public string ServerAddress { get; set; }
/// <summary>
/// 健康检查地址,默认 "/health"
/// </summary>
public string HealthCheckPath { get; set; } = "/health";
}当UseEnvironment==true 时将自动用 aspnetcore监听的地址和端口，当为false时，你需要手动指定本机的地址和端口
/// <summary>
/// 本机服务器
/// </summary>
public class LocalServer
{
/// <summary>
/// 是否自动生成
/// </summary>
public bool UseEnvironment { get; set; }
/// <summary>
/// 本机服务地址
/// </summary>
public string? LocalAddress { get; set; }
/// <summary>
/// 本机服务端口
/// </summary>
public int? LocalPort { get; set; }
}单元测试代码如下，由于git无法签入cosnul（太大）故而没有编写自动测试的测试用例
public class Tests
{
ApplicationBuilder application;
TestApplicationLifetime lifeTime = new TestApplicationLifetime();
/// <summary>
/// 测试前请先打开Consul服务端
/// </summary>
[SetUp]
public void Setup()
{
ServiceCollection services = new ServiceCollection();
var feature = new ServerAddressesFeature();
feature.Addresses.Add("http://127.0.0.1:1003");
services.AddConsul().Configure(s=>
{
var url = application.HostUrls().FirstOrDefault();
s.Id = Guid.NewGuid().ToString();
s.ServerAddress = "http://127.0.0.1:8500";
s.LocalServer = new LocalServer
{
LocalAddress =$"{url.Scheme}://{url.Host}",
LocalPort = url.Port
};
s.Name = "Test";
});
services.AddSingleton<IHostApplicationLifetime, TestApplicationLifetime>();
application = new ApplicationBuilder(services.BuildServiceProvider());
IFeatureCollection featureCollection = new FeatureCollection();
featureCollection.Set<IServerAddressesFeature>(feature);
application.Properties.Add("server.Features", featureCollection);
var fea= application.ServerFeatures.Get<IServerAddressesFeature>();
lifeTime.Start();
}
[Test]
public void Test1()
{
application.UseConsulBuilder().UseConsul();
lifeTime.StopApplication();
}
}