src/utils/FileUtils.ts

   1 import fs from 'node:fs';
   2
   3 import chalk from 'chalk';
   4
   5 import { logger } from './Logger';
   6 import { Utils } from './Utils';
   7 import type { EmptyObject, FileType, HandleErrorParams, JsonType } from '../types';
   8
   9 export class FileUtils {
  10   private constructor() {
  11     // This is intentional
  12   }
  13
  14   public static watchJsonFile<T extends JsonType>(
  15     file: string,
  16     fileType: FileType,
  17     logPrefix: string,
  18     refreshedVariable?: T,
  19     listener: fs.WatchListener<string> = (event, filename) => {
  20       if (Utils.isNotEmptyString(filename) && event === 'change') {
  21         try {
  22           logger.debug(`${logPrefix} ${fileType} file ${file} have changed, reload`);
  23           refreshedVariable && (refreshedVariable = JSON.parse(fs.readFileSync(file, 'utf8')) as T);
  24         } catch (error) {
  25           FileUtils.handleFileException(file, fileType, error as NodeJS.ErrnoException, logPrefix, {
  26             throwError: false,
  27           });
  28         }
  29       }
  30     }
  31   ): fs.FSWatcher | undefined {
  32     if (Utils.isNotEmptyString(file)) {
  33       try {
  34         return fs.watch(file, listener);
  35       } catch (error) {
  36         FileUtils.handleFileException(file, fileType, error as NodeJS.ErrnoException, logPrefix, {
  37           throwError: false,
  38         });
  39       }
  40     } else {
  41       logger.info(`${logPrefix} No ${fileType} file to watch given. Not monitoring its changes`);
  42     }
  43   }
  44
  45   public static handleFileException(
  46     file: string,
  47     fileType: FileType,
  48     error: NodeJS.ErrnoException,
  49     logPrefix: string,
  50     params: HandleErrorParams<EmptyObject> = { throwError: true, consoleOut: false }
  51   ): void {
  52     const prefix = Utils.isNotEmptyString(logPrefix) ? `${logPrefix} ` : '';
  53     let logMsg: string;
  54     switch (error.code) {
  55       case 'ENOENT':
  56         logMsg = `${fileType} file ${file} not found:`;
  57         break;
  58       case 'EEXIST':
  59         logMsg = `${fileType} file ${file} already exists:`;
  60         break;
  61       case 'EACCES':
  62         logMsg = `${fileType} file ${file} access denied:`;
  63         break;
  64       default:
  65         logMsg = `${fileType} file ${file} error:`;
  66     }
  67     if (params?.consoleOut) {
  68       logMsg = `${logMsg} `;
  69       console.warn(`${chalk.green(prefix)}${chalk.yellow(logMsg)}`, error);
  70     } else {
  71       logger.warn(`${prefix}${logMsg}`, error);
  72     }
  73     if (params?.throwError) {
  74       throw error;
  75     }
  76   }
  77 }