.net core consul 服务配置 服务发现 服务健康检测 服务变更加载

准备环境

 安装consul之后

1. 创建一个.net core webapi 举例为UsercenterService

2. nuget引用Consul组件  https://github.com/PlayFab/consuldotnet

3. 创建配置实体类 (后面涉及功能介绍时候再解释属性含义)

 1     public class AppSettings
 2     {
 3         /// <summary>
 4         /// 数据库连接字符串
 5         /// </summary>
 6         public string DbConnection { get; set; }
 7 
 8         /// <summary>
 9         /// 服务注册参数
10         /// </summary>
11         public ServiceRegisterOptions ServiceRegisterOptions { get; set; }
12     }
13 
14     public class ServiceRegisterOptions
15     {
16         /// <summary>
17         /// 是否启用
18         /// </summary>
19         public bool IsActive { get; set; }
20         /// <summary>
21         /// 服务名称
22         /// </summary>
23         public string ServiceName { get; set; }
24         /// <summary>
25         /// 服务IP或者域名
26         /// </summary>
27         public string ServiceHost { get; set; }
28         /// <summary>
29         /// 服务端口号
30         /// </summary>
31         public int ServicePort { get; set; }
32         /// <summary>
33         /// consul注册地址
34         /// </summary>
35         public string ConsulRegisterUrl { get; set; }
36         /// <summary>
37         /// 标签 例如laiwutest
38         /// </summary>
39         public string[] Tags { get; set; }
40     }
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4. appsettings配置consul服务地址和UserService配置在consul的节点key

  4.1 配置consul地址(举例是在VS调试开发环境。所以在appsettings.Development.json中配置) 

1 {
2   "ConsulForConfig": {
3     "Host": "{IP}:8500",//这里替换成自己consul服务的IP地址
4     "Prefix": "git-dev/huangqiang/usercenterRegionIIS.json"
5   }
6 }
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       4.2 在consul上创建该节点并且配置

 1 {
 2     "DbConnection": "111111111111111111111111111111111111111",
 3     "ServiceRegisterOptions":
 4     {
 5         "IsActive":true,
 6         "ServiceName":"UserCenterRegion",
 7         "ServiceHost":"{IP}",//修改{IP}为你注入的服务的ip地址
 8         "ServicePort":"{Port}",//修改{Port}为你注入的服务的端口
 9         "ConsulRegisterUrl":"{IP}:8500",//修改{IP}为你的consul服务的IP
10         "Tags":["浙江杭州"]
11     },
12 }
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获取配置  

 1   public static AppSettings AddAppSettingByConsul(this IServiceCollection sc, IConfiguration configuration)
 2         {
 3             try
 4             {
 5                 //get local consul service address configration consulclient
 6                 var consulAddress = $"http://" + configuration["ConsulForConfig:Host"];
 7                 var key = configuration["ConsulForConfig:Prefix"];
 8                 if (string.IsNullOrWhiteSpace(consulAddress) || string.IsNullOrWhiteSpace(key))
 9                 {
10                     throw new Exception("无法获取consulAddress地址或者consul key");
11                 }
12                 var consulClient = new ConsulClient(cfg => { cfg.Address = new Uri(consulAddress); });
13                 sc.AddSingleton<IConsulClient>(p => consulClient);
14                 //get app config
15                 var res = consulClient.KV.Get(key).GetAwaiter().GetResult();
16                 var resStr = Encoding.UTF8.GetString(res.Response.Value);
17                 var appSettings = JsonConvert.DeserializeObject<AppSettings>(resStr);
18                 if (appSettings == null)
19                 {
20                     throw new Exception($"appSettings 为null,consul 配置:{resStr}");
21                 }
22                 sc.AddSingleton<AppSettings>(appSettings);
23                 return appSettings;
24             }
25             catch (Exception e)
26             {
27                 _log.Main.Error($"获取consul appsettings配置异常:{e.Message}");
28                 Environment.Exit(-1);
29             }
30             return null;
31         }
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这里抽了一个扩展方法。使用的时候在Startup.cs类中的方法ConfigureServices中加入,这里弄了返回值只是偷懒下。

AddAppSettingByConsul方法逻辑:先是拿到配置的consull服务地址和Key,再通过前面nuget引用的consul组件中的consulclient获取配置,最后注入到容器

调试下 就拿到配置了。这样方便分布式服务,不用每台都配置,直接consul管理

 


 

 

配置健康检测和服务注册

 准备健康检测接口:

1     [Route("api/v1/[controller]")]
2     [ApiController]
3     public class HealthController : ControllerBase
4     {
5         [HttpGet]
6         public IActionResult Get() => Ok("ok");
7     }
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.net core 配置注册和健康检测的地址

 1  public static void UseConsul(this IApplicationBuilder app, IApplicationLifetime appLife)
 2         {
 3             try
 4             {
 5                 var appSettings = app.ApplicationServices.GetService<AppSettings>();
 6                 var consulClient = app.ApplicationServices.GetService<IConsulClient>();
 7 
 8                 //config consul health check
 9                 var healthCheck = new AgentServiceCheck
10                 {
11                     DeregisterCriticalServiceAfter = TimeSpan.FromSeconds(5),
12                     Interval = TimeSpan.FromSeconds(30),
13                     HTTP = $"{appSettings.ServiceRegisterOptions.ServiceHost}:{appSettings.ServiceRegisterOptions.ServicePort}/api/v1/Health",
14                 };
15 
16                 //service register
17                 var serviceId = $"{appSettings.ServiceRegisterOptions.ServiceName}_{appSettings.ServiceRegisterOptions.ServiceHost}:{appSettings.ServiceRegisterOptions.ServicePort}";
18                 var registration = new AgentServiceRegistration
19                 {
20                     Checks = new[] { healthCheck },
21                     Address = appSettings.ServiceRegisterOptions.ServiceHost,
22                     Port = appSettings.ServiceRegisterOptions.ServicePort,
23                     ID = serviceId,
24                     Name = appSettings.ServiceRegisterOptions.ServiceName,
25                     Tags = appSettings.ServiceRegisterOptions.Tags
26                 };
27                 consulClient.Agent.ServiceRegister(registration).GetAwaiter().GetResult();
28 
29                 //service Deregister when app stop
30                 appLife.ApplicationStopped.Register(() =>
31                 {
32                     consulClient.Agent.ServiceDeregister(serviceId).GetAwaiter().GetResult();
33                 });
34 
35 
36             }
37             catch (Exception e)
38             {
39                 _logger.Main.Error($"UseConsul error:{e.Message}");
40                 Environment.Exit(-1);
41             }
42 
43         }
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这里也是抽了个扩展方法。调用放到Startup

 

UseConsul方法解释:先是从容器中拿到前面注入的配置实体AppSettings和ConsulClient。再配置健康检测,再配置服务注册,再配置当服务关闭时候注销服务。

其中健康检测的DeregisterCriticalServiceAfter表示如果服务启动失败,多少时间内注销consul上的该服务。

服务注册的参数就不介绍了

然后跑起来之后,到consul ui瞧一瞧。是不是注册成功,心跳正常

状态为passing为正常的,刚启动时候状态会为critical。 当你的状态一直为critical时候,过了前面DeregisterCriticalServiceAfter的时间,服务将会注销,也就是注册失败。可能原因:服务地址配置有问题,consul无法访问你的health地址,也可能你的端口没打开。telnet看看

 

当都成功的时候,服务已经正常注册到consul。下面再说说服务发现和服务变更发现


 

 

服务发现和服务变更发现

服务发现调用的方法有很多,agent,catalog,health,都可以获取列表。但是agent是查询本地自己的,catalog是整个集群的,heath是查询健康的。这里用health获取举例

关键就一句话:_consulClient.Health.Service(serviceName, tag, true, queryOptions).Result。

这样就能获取到注册到consul的服务列表了,但是如果有服务变更了(新的服务注册,旧的服务停止),应该怎么办?

一般想到启动一个线程不停的去拿,是没有问题,但是有个更好的东西,“Blocking Queries”  https://www.consul.io/api/index.html

这个东西简单来说就是会记录一个版本,consul服务端通过这个版本来判断是不是已经是最新的服务列表,如果是的话,那么将会阻塞一定时间(这个时间可配置)

在c# 里面体现就是第三个参数queryOptions的WaitIndex和WaitTime,以及返回LastIndex,下面po出一部分代码。

        public void GetAllService()
        {
            _serviceIndexList.ForEach(p =>
            {
                Task.Run(() =>
                {
                    var queryOptions = new QueryOptions { WaitTime = TimeSpan.FromSeconds(_waitTime) };
                    while (true)
                    {
                        GetAgentServices(queryOptions, p.ServiceName, p.Tag);
                    }
                });
            });
        }

        public void GetAgentServices(QueryOptions queryOptions, string serviceName, string tag = null)
        {
            try
            {
                var res = _consulClient.Health.Service(serviceName, tag, true, queryOptions).Result;
                _logger.Main.Info($"GetServiceList:{serviceName} {tag} waitIndex:{res.LastIndex}");
                if (queryOptions.WaitIndex != res.LastIndex)
                {
                    queryOptions.WaitIndex = res.LastIndex;
                    var currentService = _consulServices.FirstOrDefault(p => p.ServiceName == serviceName);
                    if (currentService == null)
                    {
                        _consulServices.Add(new ConsulService
                        {
                            ServiceName = serviceName,
                            Tag = tag,
                            ServiceEntries = new ConcurrentBag<ServiceEntry>(res.Response)
                        });
                    }
                    else
                    {
                        currentService.ServiceEntries = new ConcurrentBag<ServiceEntry>(res.Response);
                    }
                }
            }
            catch (AggregateException ae)
            {
                _logger.Main.Error($"consul获取{serviceName},{tag}服务列表资源错误:{ae.Flatten()}",ae);
            }
            catch (Exception e)
            {
                _logger.Main.Error($"consul获取{serviceName},{tag}服务列表资源错误",e);
            }
        }
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注:代码中的_serviceIndexList是存着需要获取哪些服务的服务tag,_consulServices是程序维护的最新服务列表

 

posted @ 2019-03-19 13:34  TeemoHQ  阅读(1558)  评论(2编辑  收藏  举报