Initialising the tracer before the logger is imported is unergonomic

[BridgeAR]

How can I initialise the tracer before the logger is imported if I want to pass that very logger to the tracer init method, as shown in https://datadoghq.dev/dd-trace-js/#custom-logging?

Originally posted by @ab-pm in #1908

[BridgeAR]

It works by lazily defining the logger. I can not think of a much better way.

It would look roughly like:

process.env.DD_TRACE_DEBUG = 'true'
let internalLogger
const getInternalLogger = () => {
  if (internalLogger === undefined) {
    internalLogger = require('bunyan').createLogger({ name: 'dd-trace', level: 'trace' })
  }
  return internalLogger
}
const tracer = require('dd-trace').init({
  logger: {
    error: (error) => getInternalLogger().error(error),
    warn: (message) => getInternalLogger().warn(message),
    info: (message) => getInternalLogger().info(message),
    debug: (message) => getInternalLogger().trace(message),
  },
})

I think this is not very intuitive to configure the logger, so having a dedicated useLogger method would be much better than the init call. That way it would not have to be written as above.