是否可以信任ILogger捕获/记录所有未捕获的异常？

Question

这个问题不是关于Rollbar tho：）

Answer 1

不。Ilogger是一个接口。它什么也做不了。相反，Ilogger的实现应该记录未捕获的异常。听起来好像Rollbar已经在进行日志记录，所以您应该继续使用它来记录未捕获的异常，或者切换到其他库，如NLog、Serilog或log4net。

就我个人而言，我发现一些库在不同的情况下确实会遗漏消息，所以测试日志库很重要。仅仅相信信息是正确写的是不够的。您可以编写单元测试，以确保您的代码使用MOQ正确地记录异常。下面是本文中的一个示例。

_loggerMock.Verify
(
    l => l.Log
    (
        //Check the severity level
        LogLevel.Error,
        //This may or may not be relevant to your scenario
        It.IsAny<EventId>(),
        //This is the magical Moq code that exposes internal log processing from the extension methods
        It.Is<It.IsAnyType>((state, t) =>
            //This confirms that the correct log message was sent to the logger. {OriginalFormat} should match the value passed to the logger
            //Note: messages should be retrieved from a service that will probably store the strings in a resource file
            CheckValue(state, LogTest.ErrorMessage, "{OriginalFormat}") &&
            //This confirms that an argument with a key of "recordId" was sent with the correct value
            //In Application Insights, this will turn up in Custom Dimensions
            CheckValue(state, recordId, nameof(recordId))
    ),
    //Confirm the exception type
    It.IsAny<NotImplementedException>(),
    //Accept any valid Func here. The Func is specified by the extension methods
    (Func<It.IsAnyType, Exception, string>)It.IsAny<object>()),
    //Make sure the message was logged the correct number of times
    Times.Exactly(1)
);

但是，即使这样也不能保证Rollbar或其他记录器一定会将您的消息发送到日志位置。您只能通过观察记录器的输出来确认这一点。