Log handler setup function is inconsistent

[ross-weir]

Is your feature request related to a problem? Please describe.

When creating logger handlers some of the handler setup functions are sync while others are async.

For example, I have a function that creates a logger for my modules like so:

export function createLogger(
  config: ErgomaticConfig,
  name: string,
): Logger {
  const logHandlers = [];
  const level = config.logLevel;
  const fileHandler = new handlers.FileHandler(level, {
    filename: join(logsDir(), "file.log"),
  });

  fileHandler.setup();

  logHandlers.push(
    new handlers.ConsoleHandler(level, {
      formatter,
    }),
    fileHandler,
  );

  return new Logger(name, level, {
    handlers: logHandlers,
  });
}

That I was using in the constructor of my modules:

class Module {
  constructor() {
    this.logger = createLogger(...)
  }
}

I decided I wanted to move over to RotatingFileHandler for log file rotation. My previous setup no longer works because RotatingFileHandler.setup is async whereas FileHandler.setup is sync, so this requires me to refactor all my classes if I want to use it.

Describe the solution you'd like

Make the API consistent for log handlers, either all async or all sync.

IMO there could have been setup & setupSync like other Deno APIs but this probably can't be changed while preserving backwards compatibility.

Alternatively add a SyncRotatingFileHandler that can be used in sync contexts

[ross-weir]

Looking into this a bit it looks like RotatingFileHandler.setup being async might be an oversight, it appears the log.setup method was made sync a while ago ebeecac

Additionally all the documentation still incorrectly has the setup function as async:

deno_std/log/mod.ts

Line 67 in 159060b

* await log.setup({

[lino-levan]

Seems like a reasonable change. I'll pick it up.