前言
前文介绍了一些基本思路,那么这里介绍一下,服务如何与配置文件配合。
正文
服务:
public interface ISelfService { void ShowLog(); } public class SelfService : ISelfService { public ILogger<SelfService> _Logger; public SelfService(ILogger<SelfService> logger) { _Logger = logger; } public void ShowLog() { _Logger.LogInformation("I am a log."); } }
配置:
{ "Logging": { "LogLevel": { "Default": "Debug", "Microsoft": "Warning", "Microsoft.Hosting.Lifetime": "Information" }, "Console": { "LogLevel": { "Default": "Information", "Program": "Trace", "loggerObj": "Debug" } } } }
测试代码:
static void Main(string[] args) { IConfigurationBuilder configurationBuilder = new ConfigurationBuilder(); configurationBuilder.AddJsonFile("appsettings.json",optional:false,reloadOnChange:true); var config = configurationBuilder.Build(); IServiceCollection serviceCollection = new ServiceCollection(); serviceCollection.AddSingleton<IConfiguration>(p=>config); serviceCollection.AddSingleton<ISelfService,SelfService>(); serviceCollection.AddLogging(builder => { builder.AddConfiguration(config.GetSection("Logging")); builder.AddConsole(); }); IServiceProvider service = serviceCollection.BuildServiceProvider(); var selfService = service.GetService<ISelfService>(); selfService.ShowLog(); Console.ReadKey(); }
结果:
那么如何要配置单个服务的Logger级别呢?
{ "Logging": { "LogLevel": { "Default": "Debug", "Microsoft": "Warning", "Microsoft.Hosting.Lifetime": "Information" }, "Console": { "LogLevel": { "Default": "Information", "Program": "Trace", "loggerObj": "Debug", "ConfigureDemo.SelfService": "Error" } } } }
设置这个ConfigureDemo.SelfService的值就可以。为什么这样呢?
看ILogger 的实现类Logger:
public Logger(ILoggerFactory factory) { if (factory == null) { throw new ArgumentNullException(nameof(factory)); } _logger = factory.CreateLogger(TypeNameHelper.GetTypeDisplayName(typeof(T), includeGenericParameters: false, nestedTypeDelimiter: '.')); }
这里会创建一个默认的TypeNameHelper.GetTypeDisplayName(typeof(T))的logger实例名字。
这个会获取到全名,故而设置好全名,那么会去使用这个配置。
我们一般打印log的时候,要去输出时间,建议这样写:
public class SelfService : ISelfService { public ILogger<SelfService> _Logger; public SelfService(ILogger<SelfService> logger) { _Logger = logger; } public void ShowLog() { _Logger.LogInformation("I am a log.",DateTime.Now); } }
效果如下:
_Logger.LogInformation("I am a log.",DateTime.Now);
这样写的好处因为我们的log有过滤机制,如果我们过滤不输出,那么"I am a log."和DateTime.Now就不会去做拼接执行。
这也是一种延迟思想的表现。
结
以上只是个人整理,如有错误,望请指点。
下一节日志作用域