如何将文件名传递给 winston logger？

Question

我将 winston 设置为记录器，效果很好。但是，我有几个进程要记录到不同的文件中。如何将文件名传递给记录器实例？

我用这个作为我的区块

'use strict';
const { createLogger, format, transports } = require('winston');
require('winston-daily-rotate-file');
const fs = require('fs');
const path = require('path');
const logDir = '/codeforge/log';

const dailyRotateFileTransport = new transports.DailyRotateFile({
  filename: `${logDir}/%DATE%-engine.log`,
  maxSize: "1g",
  maxDays: "3d",
  zippedArchive: true,
  datePattern: 'YYYY-MM-DD'
});

const logger = createLogger({
  // change level if in dev environment versus production
  level: 'debug', 
  maxsize: '500m',
  format: format.combine(
    format.timestamp({
      format: 'YYYY-MM-DD HH:mm:ss'
    }),
    // for the log file
    format.printf(info => `${info.timestamp} ${info.level}: ${info.message}`)
  ),
  transports: [
    new transports.Console({
      level: 'info',
      format: format.combine(
        format.colorize(),
        format.printf(
          info => `${info.message}`
        )
      )
    }),
    dailyRotateFileTransport
  ]
});

module.exports = logger

我想传入一个文件名来替换“-engine”部分，以便为其创建或附加一个日志文件。

感谢任何提示。

Answer 1

将您的记录器变成您调用的函数

const log = require('logger')('myfilename');
log.info('happy logging')

代码：

'use strict';
const { createLogger, format, transports } = require('winston');
require('winston-daily-rotate-file');
const fs = require('fs');
const path = require('path');
const logDir = '/codeforge/log';

const dailyRotateFileTransport = filename => new transports.DailyRotateFile({
  filename: `${logDir}/%DATE%-${filename}.log`,
  maxSize: "1g",
  maxDays: "3d",
  zippedArchive: true,
  datePattern: 'YYYY-MM-DD'
});

const logger = function(filename){
  return createLogger({
    // change level if in dev environment versus production
    level: 'debug', 
    maxsize: '500m',
    format: format.combine(
      format.timestamp({
        format: 'YYYY-MM-DD HH:mm:ss'
      }),
      // for the log file
      format.printf(info => `${info.timestamp} ${info.level}: ${info.message}`)
    ),
    transports: [
      new transports.Console({
        level: 'info',
        format: format.combine(
          format.colorize(),
          format.printf(
            info => `${info.message}`
          )
        )
      }),
      
      dailyRotateFileTransport(filename)
    ]
  });
}

module.exports = logger // is now a function

Answer 2

我不想多次创建或重新初始化 Logger 实例，我们可以通过运行

检查

DEBUG=winston* yarn start

我正在使用 child logger ，这是我的打字稿记录器，

import winston from 'winston';

const { transports, format } = winston;

const { LOG_LEVEL, APP_ENV } = process.env;

const logFormatter = APP_ENV === 'dev'
  ? format.combine(
      winston.format.timestamp(),
      winston.format.colorize(),
      winston.format.printf((meta: any) => {
        const { level, message, timestamp, namespace, stack, ...restMeta } = meta;
        const displayNamespace = namespace ? `[${namespace}] -` : '';
        const stackMessage = stack ? `\n${stack}` : '';
        const otherMetaMessage = Object.keys(restMeta).length > 0 ? `\n${JSON.stringify(restMeta)}` : '';
        return `${timestamp} ${displayNamespace} ${level}: ${message} ${otherMetaMessage}${stackMessage}`;
      })
    )
  : format.combine(winston.format.timestamp(), winston.format.json());

const logger = winston.createLogger({
  level: LOG_LEVEL || 'debug',
  format: logFormatter,
  transports: [
    new winston.transports.Console({
      silent: APP_ENV === 'test',
    }),
  ],
});

export const Logger = (namespace?: string) => {
  if (namespace) {
    return logger.child({ namespace });
  }
  return logger;
};

用法：服务-abc.js

const LOGGER = Logger('service:abc');
export class serviceAbc{
   doSomething(){
      LOGGER.info("do something");
   }
}

Answer 3

如果你正在使用 ES6 模块导入，这里有一个可行的建议：

logger.js

import winston from "winston";
import { resolve } from "path";
import { fileURLToPath } from "url";

const { format, transports, createLogger } = winston;
const { combine, timestamp, printf } = format;

export default (meta_url) => {

  const root = resolve("./");
  const file = fileURLToPath(new URL(meta_url));
  const file_path = file.replace(root, "");

  const customFormat = printf(({ level, message, timestamp, stack }) => {
    return `${timestamp} [${level}] ${file_path}: ${stack || message}`;
  });

  const loggerInstance = createLogger({
    level: "info",
    format: combine(
      timestamp({ format: "YYYY-MM-DD HH:mm:ss" }),
      format.splat(),
      format.errors({ stack: true }),
      customFormat
    ),
    defaultMeta: { service: "user-service" },
    transports: [
      new transports.File({ filename: "log/error.log", level: "error" }),
      new transports.File({ filename: "log/common.log" }),
    ],
  });

  // Log also to console if not in production
  if (process.env.NODE_ENV === "development") {
    loggerInstance.add(
      new transports.Console({
        format: combine(colorize(), customFormat),
      })
    );
  }

  return loggerInstance;
};

server/index.js

import Logger from "../logger.js";
const logger = Logger(import.meta.url);

logger.info("App running on http://localhost:%i", 5000);

结果：

2021-12-17 15:09:38 [info] /server/index.js: App running on http://localhost:5000

工作原理：

在 logger.js 中，我们 return 一个包装函数，它接受文件的 import.meta.url 作为参数，然后 returns 记录器实例。

在记录器内部，我们简化了绝对路径，并将其传递给自定义记录器格式以进行输出。如果你不想美化路径，只需使用const file_path = fileURLToPath(new URL(meta_url))

如何将文件名传递给 winston logger？

how to pass a filename to winston logger?

node.js

winston