node.js - 在节点 js 中使用 log4js 将日志写入文件

Question

我的代码是：

log4js.loadAppender('file');
log4js.addAppender(log4js.appenders.file('logs/cheese.log'), 'cheese');
logger.setLevel('DEBUG');

logger.trace('Entering cheese testing');
logger.debug('Got cheese.');
logger.info('Cheese is Gouda.');
logger.warn('Cheese is quite smelly.');
logger.error('Cheese is too ripe!');
logger.fatal('Cheese was breeding ground for listeria.');

它正在创建一个名为“cheese”的文件，但其中没有任何内容。那里面的内容怎么写？

Answer 1

此解决方案可帮助您在您的文件夹日志中创建日志文件夹和三个文件 error.log、debug.log 和 info.log。为我工作。谢谢。

var log4js = require('log4js'); // include log4js

log4js.configure({ // configure to use all types in different files.
    appenders: [
        {   type: 'file',
            filename: "/logs/error.log", // specify the path where u want logs folder error.log
            category: 'error',
            maxLogSize: 20480,
            backups: 10
        },
        {   type: "file",
            filename: "/logs/info.log", // specify the path where u want logs folder info.log
            category: 'info',
            maxLogSize: 20480,
            backups: 10
        },
        {   type: 'file',
            filename: "/logs/debug.log", // specify the path where u want logs folder debug.log
            category: 'debug',
            maxLogSize: 20480,
            backups: 10
        }
    ]
});

var loggerinfo = log4js.getLogger('info'); // initialize the var to use.
var loggererror = log4js.getLogger('error'); // initialize the var to use.
var loggerdebug = log4js.getLogger('debug'); // initialize the var to use.

loggerinfo.info('This is Information Logger');
loggererror.info('This is Error Logger');
loggerdebug.info('This is Debugger');

Answer 2

在上面的代码中，您缺少记录器声明：添加行var logger = log4js.getLogger('cheese');

整个代码块如下：

var log4js = require('log4js');

log4js.loadAppender('file');
log4js.addAppender(log4js.appenders.file('logs/cheese.log'), 'cheese');

var logger = log4js.getLogger('cheese');

logger.setLevel('DEBUG');
logger.trace('Entering cheese testing');
logger.debug('Got cheese.');
logger.info('Cheese is Gouda.');
logger.warn('Cheese is quite smelly.');
logger.error('Cheese is too ripe!');
logger.fatal('Cheese was breeding ground for listeria.');

参考

Answer 3

在2.x版中。

你需要做这样的事情：

var log4js = require('log4js');
log4js.configure({
  appenders: { 'file': { type: 'file', filename: 'logs/cheese.log' } },
  categories: { default: { appenders: ['file'], level: 'debug' } }
});

var logger = log4js.getLogger('cheese');

logger.setLevel('DEBUG');
logger.trace('Entering cheese testing');
logger.debug('Got cheese.');
logger.info('Cheese is Gouda.');
logger.warn('Cheese is quite smelly.');
logger.error('Cheese is too ripe!');
logger.fatal('Cheese was breeding ground for listeria.');

如果您想根据日志消息中的属性（如上面的文件名）动态创建文件，请查看multiFile appender。

Answer 4

Log4js 具有多文件配置功能。看这里

log4js.configure({
  appenders: {
    out: { type: 'stdout' },
    afile: { type: 'multiFile', base: 'logs/', property: 'categoryName', extension: '.log' }
  },
  categories: {
    default: { appenders: ['out'], level: 'info' },
    tofile: { appenders: ['afile'], level: 'debug' }
  }
});

然后开始登录文件 logs/xyz.log：

const xyzlog = log4js.getLogger('tofile.xyz');
xyzlog.info('Hello!');