Winston没有将日志写入文件

Question

我在Winston中为错误和警告做了两个传输，据说是写到文件的。现有的控制台日志传输工作正常，我也检查了下 pm2 logs 并看到了日志，但文件的传输没有保存任何东西。

'use strict';

const winston = require('winston');
const m = require('moment-timezone');
let logger = null;
/**
 * Initializes the logger
 * @param {object} configLogging
 */
module.exports.initialize = function initialize(configLogging) {
  const dateFormat = 'dddd, MMMM Do YYYY, h:mm:ss a';

  logger = new winston.Logger({
    transports: [
      new (winston.transports.Console)({
        name: 'info-console',
        level: configLogging.level,
        colorize: true,
        timestamp: function() { return m.utc().format(dateFormat); }
      }),
      new (winston.transports.File)({
        name: 'warning-file',
        filename: 'warning-file.log',
        level: 'warning'
      }),
      new (winston.transports.File)({
        name: 'error-file',
        filename: 'error-file.log',
        level: 'error'
      })
    ]
  });

  logger.info('Starting logging service');
};

/**
 * Gets the logger instance
 * @returns {LoggerInstance} winLogger
 */
module.exports.get = function get() {
  return logger;
};

Answer 1

请创建一个log.js文件，并写上这所有的代码。

var winston = require('winston');
const env = process.env.NODE_ENV;
const logDir = 'logs';
const fs = require('fs');

if (!fs.existsSync(logDir)) {
  fs.mkdirSync(logDir);
 }

const now = new Date();
var logger = new(winston.Logger)({
transports: [

    new winston.transports.File({
        name: 'error-file',
        filename: './logs/exceptions.log',
        level: 'error',
        json: false
    }),

    new(require('winston-daily-rotate-file'))({
        filename: `${logDir}/-apimodules.log`,
        timestamp: now,
        datePattern: 'dd-MM-yyyy',
        prepend: true,
        json: false,
        level: env === 'development' ? 'verbose' : 'info'
    })
],
exitOnError: false
});

module.exports = logger;
module.exports.stream = {
  write: function(message, encoding) {
    logger.info(message);
    console.log('message=', message);
  }
};

对于添加日志，在需要记录的地方使用这个文件，使用这个代码。

var logger = require('./path of/log.js');
logger.info('*** Requested for First log... ***');

Answer 2

为了现代化，这里是上面答案的工作代码，因为上面的答案在winston 3.2.1的最新版本中无法使用。这是文件log.js的工作代码。

const fs = require('fs');

var winston = require('winston');

const env = process.env.NODE_ENV;
const logDir = 'logs';

if (!fs.existsSync(logDir)) {
  fs.mkdirSync(logDir);
}

const now = new Date();
var logger = winston.createLogger({
  transports: [
    new winston.transports.File({
      name: 'error-file',
      filename: './logs/exceptions.log',
      level: 'error',
      json: false,
    }),

    new (require('winston-daily-rotate-file'))({
      filename: `${logDir}/-apimodules.log`,
      timestamp: now,
      datePattern: 'dd-MM-yyyy',
      prepend: true,
      json: false,
      level: env === 'development' ? 'verbose' : 'info',
    }),
  ],
  exitOnError: false,
});

module.exports = logger;

module.exports.stream = {
  write: function (message) {
    logger.info(message);
    console.log('message = ', message);
  },
};

注意，这将数据输出到一个名为logs的根目录下。