TracingChannel 通道
🌐 TracingChannel Channels
TracingChannel 是多个 diagnostics_channel 的集合，表示单个可跟踪操作执行生命周期中的特定点。其行为分为五个 diagnostics_channel，包括 start、end、asyncStart、asyncEnd 和 error。单个可跟踪操作将在所有事件之间共享相同的事件对象，这对于通过 weakmap 管理关联非常有用。
🌐 A TracingChannel is a collection of several diagnostics_channels representing
specific points in the execution lifecycle of a single traceable action. The
behaviour is split into five diagnostics_channels consisting of start,
end, asyncStart, asyncEnd, and error. A single traceable action will
share the same event object between all events, this can be helpful for
managing correlation through a weakmap.
当任务“完成”时，这些事件对象将会扩展包含 result 或 error 的值。对于同步任务，result 将是返回值，而 error 则是函数中抛出的任何异常。对于基于回调的异步函数，result 将是回调的第二个参数，而 error 要么是在 end 事件中可见的抛出错误，要么是在 asyncStart 或 asyncEnd 事件中的第一个回调参数。
🌐 These event objects will be extended with result or error values when
the task "completes". In the case of a synchronous task the result will be
the return value and the error will be anything thrown from the function.
With callback-based async functions the result will be the second argument
of the callback while the error will either be a thrown error visible in the
end event or the first callback argument in either of the asyncStart or
asyncEnd events.
跟踪通道应遵循以下命名模式：
🌐 Tracing channels should follow a naming pattern of:
tracing:module.class.method:start或tracing:module.function:starttracing:module.class.method:end或tracing:module.function:endtracing:module.class.method:asyncStart或tracing:module.function:asyncStarttracing:module.class.method:asyncEnd或tracing:module.function:asyncEndtracing:module.class.method:error或tracing:module.function:error