可以用if语句优雅地配置Serilog？

我的Serilog配置代码如下所示：

Log.Logger = new LoggerConfiguration()
    .Enrich.WithExceptionDetails()
    .Enrich.FromLogContext()
    .MinimumLevel.Warning()
//  .MinimumLevel.Override("Microsoft", LogEventLevel.Verbose)
//  .MinimumLevel.Override("System", LogEventLevel.Verbose)
//  .MinimumLevel.Override("Microsoft.AspNetCore.Authentication", LogEventLevel.Verbose)
    .WriteTo.Console( outputTemplate: "[{Timestamp:HH:mm:ss} {Level}] {SourceContext}{NewLine}{Message:lj}{NewLine}{Exception}{NewLine}", theme: AnsiConsoleTheme.Literate )
//  .WriteTo.File()
    .CreateLogger();

我想在运行时更改此配置,不幸的是,因为Serilog使用“流利的”样式的API,这使它有些混乱.例如,如果我想在运行时启用或禁用控制台和文件记录：

Boolean enableConsoleLogging = ...
Boolean enableFileLogging = ...

LoggerConfiguration builder = new LoggerConfiguration()
    .Enrich.WithExceptionDetails()
    .Enrich.FromLogContext()
    .MinimumLevel.Warning();

if( enableConsoleLogging )
{
    builder = builder
        .WriteTo.Console( outputTemplate: "[{Timestamp:HH:mm:ss} {Level}] {SourceContext}{NewLine}{Message:lj}{NewLine}{Exception}{NewLine}", theme: AnsiConsoleTheme.Literate )
}

if( enableFileLogging )
{
    builder = builder
        .WriteTo.File( ... )
}
Log.Logger = builder.CreateLogger();

…并不十分优雅.

我知道我可以添加自己的If扩展方法(但我不希望扩展这样的现有API设计,即使看起来确实更漂亮)：

Log.Logger = new LoggerConfiguration()
    .Enrich.WithExceptionDetails()
    .Enrich.FromLogContext()
    .MinimumLevel.Warning()
    .If( enableConsoleLogging, b => b.WriteTo.Console( outputTemplate: "[{Timestamp:HH:mm:ss} {Level}] {SourceContext}{NewLine}{Message:lj}{NewLine}{Exception}{NewLine}", theme: AnsiConsoleTheme.Literate ) )
    .If( enableFileLogging, b => b.WriteTo.File( ... ) )
    .CreateLogger();


public static LoggerConfiguration If( this LoggerConfiguration cfg, Boolean test, Func<LoggerConfiguration,LoggerConfiguration> action )
{
    if( test ) return action( cfg );
    else       return cfg;
}

有哪些替代方案可以在运行时切换不同的Serilog选项？是否可以与其他“ Fluent” API一起使用？

解决方法:

我认为,要使其优雅并仍在代码中进行,就必须扩展API并创建自己的扩展方法,以封装条件检查并使用正确的接收器和参数更新构建器.

就像是

Log.Logger = new LoggerConfiguration()
    .Enrich.WithExceptionDetails()
    .Enrich.FromLogContext()
    .MinimumLevel.Warning()
    .WriteToConsoleIfEnabled()  // <---
    .WriteToFileIfEnabled()     // <---
    .CreateLogger();

另一方面,您是否考虑过改用Serilog.Settings.AppSettings或Serilog.Settings.Configuration？代码中的配置变得更加简洁,您可以根据需要在配置文件中添加/删除接收器…

Log.Logger = new LoggerConfiguration()
  .ReadFrom.AppSettings()
  .CreateLogger()

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <appSettings>
    <add key="serilog:minimum-level" value="Verbose" />

    <add key="serilog:using:Console" value="Serilog.Sinks.Console" />
    <add key="serilog:write-to:Console" />

    <add key="serilog:using:RollingFile" value="Serilog.Sinks.RollingFile" />
    <add key="serilog:write-to:RollingFile.pathFormat" value="C:\myapp-{Date}.txt" />
    <add key="serilog:write-to:RollingFile.retainedFileCountLimit" value="10" />

    <!-- //etc... -->
  </appSettings>
</configuration>

标签：fluent,serilog,c
来源： https://codeday.me/bug/20191108/2008163.html