Suggested improvements to fileAsyncTransport.

[charlesmchen-replit]

Hi there @alessandro-bottamedi, thanks for making react-native-logs.

I'd like to offer a few suggestions for future improvements. They all apply to fileAsyncTransport.

• Option to auto-create log directories, if missing. e.g. if app wants to log to ${documentsDirectory}/logs}, that "logs" subdirectory might be missing when app is first installed. Perhaps a createDirectories field in the config?
• Option to roll over log files if they exceed a max file size on disk. Perhaps a maxFileSize field in the config?
• Option to clean up old log files on launch, retaining just the N most recent log files. Perhaps a maxLogFileCount field in the config?

Cheers!

[charlesmchen-replit]

It might be nice to add a means to flush logs to disk.

[alessandro-bottamedi]

I believe that it's better to perform all these tasks before the initialization of react-native-logs, also for performance reasons. It's better to avoid putting them in the fileAsyncTransport, which is executed every time an attempt is made to write a log. For example, we could compress the last log file upon opening the app:

import { zip } from 'react-native-zip-archive'
import RNFS from 'react-native-fs'
import { logger, fileAsyncTransport } from "react-native-logs"

let date = new Date();
date.setDate(date.getDate() - 1);

let d = date.getDate();
let m = date.getMonth() + 1;
let y = date.getFullYear();

const targetPath = `${DocumentDirectoryPath}/logs_${d}-${m}-${y}.zip`
const sourcePath = `${DocumentDirectoryPath}/logs_${d}-${m}-${y}`

RNFS.exists(sourcePath)
  .then((exists) => {
    if (exists) {
      zip(sourcePath, targetPath)
      .then((path) => {
        RNFS.unlink(filePath)
      })
      .catch((error) => {
        console.error(error)
      })
  })
  .catch((error) => {
    console.error(error);
  });


const config = {
  severity: "debug",
  transport: fileAsyncTransport,
  transportOptions: {
    FS: RNFS,
    fileName: `logs_{date-today}`, // Create a new file every day
  },
};

I haven't tested this code; there might be errors...