src/utils/FileUtils.ts

   1 import fs from 'fs';
   2
   3 import chalk from 'chalk';
   4
   5 import logger from './Logger';
   6 import Utils from './Utils';
   7 import type { EmptyObject } from '../types/EmptyObject';
   8 import type { HandleErrorParams } from '../types/Error';
   9 import type { FileType } from '../types/FileType';
  10 import type { JsonType } from '../types/JsonType';
  11
  12 export default class FileUtils {
  13   private constructor() {
  14     // This is intentional
  15   }
  16
  17   public static watchJsonFile<T extends JsonType>(
  18     logPrefix: string,
  19     fileType: FileType,
  20     file: string,
  21     refreshedVariable?: T,
  22     listener: fs.WatchListener<string> = (event, filename) => {
  23       if (!Utils.isEmptyString(filename) && event === 'change') {
  24         try {
  25           logger.debug(`${logPrefix} ${fileType} file ${file} have changed, reload`);
  26           refreshedVariable && (refreshedVariable = JSON.parse(fs.readFileSync(file, 'utf8')) as T);
  27         } catch (error) {
  28           FileUtils.handleFileException(logPrefix, fileType, file, error as NodeJS.ErrnoException, {
  29             throwError: false,
  30           });
  31         }
  32       }
  33     }
  34   ): fs.FSWatcher | undefined {
  35     if (!Utils.isEmptyString(file)) {
  36       try {
  37         return fs.watch(file, listener);
  38       } catch (error) {
  39         FileUtils.handleFileException(logPrefix, fileType, file, error as NodeJS.ErrnoException, {
  40           throwError: false,
  41         });
  42       }
  43     } else {
  44       logger.info(`${logPrefix} No ${fileType} file to watch given. Not monitoring its changes`);
  45     }
  46   }
  47
  48   public static handleFileException(
  49     logPrefix: string,
  50     fileType: FileType,
  51     file: string,
  52     error: NodeJS.ErrnoException,
  53     params: HandleErrorParams<EmptyObject> = { throwError: true, consoleOut: false }
  54   ): void {
  55     const prefix = !Utils.isEmptyString(logPrefix) ? `${logPrefix} ` : '';
  56     let logMsg: string;
  57     switch (error.code) {
  58       case 'ENOENT':
  59         logMsg = `${fileType} file ${file} not found:`;
  60         break;
  61       case 'EEXIST':
  62         logMsg = `${fileType} file ${file} already exists:`;
  63         break;
  64       case 'EACCES':
  65         logMsg = `${fileType} file ${file} access denied:`;
  66         break;
  67       default:
  68         logMsg = `${fileType} file ${file} error:`;
  69     }
  70     if (params?.consoleOut) {
  71       logMsg = `${logMsg} `;
  72       console.warn(`${chalk.green(prefix)}${chalk.yellow(logMsg)}`, error);
  73     } else {
  74       logger.warn(`${prefix}${logMsg}`, error);
  75     }
  76     if (params?.throwError) {
  77       throw error;
  78     }
  79   }
  80 }