Fix configurable log level

[ogallagher]

• Create reproduceable isolated example and raise as new issue to pino repo.
• Use custom workaround for desired behavior: cascade parent log level update to all children.

[ogallagher]

In both cjs and mjs local tests, I see that updating the parent log level does not affect its children. For now, it seems I have to propogate the log level update to its children myself.

[ogallagher]

Created issue pinojs/pino#2130

[ogallagher]

Use custom workaround for desired behavior

Planning to create a map of known child loggers. Then add a level-change listener to the root logger to cascade level updates to children. Note the listener is called even when updating child logger levels, so the source logger instance that emitted the event must be checked.

const loggerChildren = new Map()

// ...

logger.addListener('level-change', (level, _val, _prevLevel, _prevVal, source) => {
  if (source === loggerRoot) {
    for (let loggerChild of loggerChildren.values()) {
      loggerChild.level = level
    }
  }
})

[ogallagher]

I will go with a custom setLevel method, rather than a listener, to reduce redundant execution of the handler from child logger level updates.