Chapter 9. Logging

Logging is important in troubleshooting and debugging. By default logging is turned off. To enable logging, you must set a logging level and provide a delegate function to receive the log messages.

9.1. Setting the log output level

The library emits log traces at different levels:

  • Error
  • Warning
  • Information
  • Verbose

The lowest log level, Error, traces only error events and produces the fewest log messages. A higher log level includes all the log levels below it and generates a larger volume of log messages.

// Enable Error logs only.
Trace.TraceLevel = TraceLevel.Error
// Enable Verbose logs. This includes logs at all log levels.
Trace.TraceLevel = TraceLevel.Verbose

9.2. Enabling protocol logging

The Log level Frame is handled differently. Setting trace level Frame enables tracing outputs for AMQP protocol headers and frames.

Tracing at one of the other log levels must be logically ORed with Frame to get normal tracing output and AMQP frame tracing at the same time. For example

// Enable just AMQP frame tracing
Trace.TraceLevel = TraceLevel.Frame;
// Enable AMQP Frame logs, and Warning and Error logs
Trace.TraceLevel = TraceLevel.Frame | TraceLevel.Warning;

The following code writes AMQP frames to the console.

Example: Logging delegate

Trace.TraceLevel = TraceLevel.Frame;
Trace.TraceListener = (f, a) => Console.WriteLine(
        DateTime.Now.ToString("[hh:mm:ss.fff]") + " " + string.Format(f, a));