Consul配置中心

利用Consul的Key-Value进行做配置中心，进行统一管理及实时更新配置，项目中有时候会用到单例模式，如Redis、ES等，这个时候就需要进行一个通知变化单例模式进行调整

1、首先建立对接Consul配置中心，引入Winton.Extensions.Configuration.Consul，在Program中配置

 public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseStartup<Startup>();
                }).ConfigureAppConfiguration(
                    builder =>
                    {
                        builder
                            .AddConsul(
                                "appsettings.json",
                                options =>
                                {
                                    options.ConsulConfigurationOptions =
                                        cco => { cco.Address = new Uri("http://127.0.0.1:8500"); };
                                    options.ReloadOnChange = true;
                                }).AddConsul("XXXXX.json", o =>
                                {
                                    o.ConsulConfigurationOptions =
                                        cco => { cco.Address = new Uri("http://127.0.0.1:8500"); };
                                    o.ReloadOnChange = true;
                                })
                            .AddEnvironmentVariables();
                    }).UseSerilog((context, configuration) =>
                {
                    configuration
                        .ReadFrom.Configuration(context.Configuration)
                        .Enrich.FromLogContext()
                        .WriteTo.Console();

                });

2、对IConfiguration进行监听变化，利用ChangeToken进行封装成一个类进行统一处理

public sealed class ConfigHelper
    {
        private static IConfiguration _configuration;
        public static void SetConfiguration(IConfiguration configuration)
        {
            _configuration = configuration;
        }
        /// <summary>
        /// 获取配置，可直接获取子级，形式PersonInfo:name"
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="key"></param>
        /// <returns></returns>
        public static T GetAppsetting<T>(string key)
        {
            if (_configuration != null)
            {
                if (!string.IsNullOrEmpty(key))
                {
                    return _configuration.GetSection(key).Get<T>();
                }
                throw new Exception("键不能为空");
            }
            else
                throw new Exception("Configuration未初始化");
        }
        /// <summary>
        /// 监听IConfiguration变化
        /// </summary>
        /// <param name="action"></param>
        public static void ConfigHasChangeSetFunc(Action action)
        {
            if (_configuration != null)
            {
                ChangeToken.OnChange(() => _configuration.GetReloadToken(), action);
            }
            else
                throw new Exception("Configuration未初始化");
        }
    }