src/utils/FileUtils.ts

   1 import { type FSWatcher, readFileSync, watch, type WatchListener } from 'node:fs'
   2
   3 import type { FileType, JsonType } from '../types/index.js'
   4
   5 import { handleFileException } from './ErrorUtils.js'
   6 import { logger } from './Logger.js'
   7 import { isNotEmptyString } from './Utils.js'
   8
   9 export const watchJsonFile = <T extends JsonType>(
  10   file: string,
  11   fileType: FileType,
  12   logPrefix: string,
  13   refreshedVariable?: T,
  14   listener: WatchListener<string> = (event, filename) => {
  15     if (isNotEmptyString(filename) && event === 'change') {
  16       try {
  17         logger.debug(`${logPrefix} ${fileType} file ${file} have changed, reload`)
  18         refreshedVariable != null &&
  19           (refreshedVariable = JSON.parse(readFileSync(file, 'utf8')) as T)
  20       } catch (error) {
  21         handleFileException(file, fileType, error as NodeJS.ErrnoException, logPrefix, {
  22           throwError: false,
  23         })
  24       }
  25     }
  26   }
  27 ): FSWatcher | undefined => {
  28   if (isNotEmptyString(file)) {
  29     try {
  30       return watch(file, listener)
  31     } catch (error) {
  32       handleFileException(file, fileType, error as NodeJS.ErrnoException, logPrefix, {
  33         throwError: false,
  34       })
  35     }
  36   } else {
  37     logger.info(`${logPrefix} No ${fileType} file to watch given. Not monitoring its changes`)
  38   }
  39 }