Question

是否可以获取每个日志输出的行号和文件？

例如：

{{1}}

应在日志文件中指定'some message'来自myFile.js第4行。

Answer 1

您可以将文件名传递为label，您可以从callingModule获取文件名。

创建logger.js文件和代码，如

var winston = require('winston');
var getLabel = function (callingModule) {
    var parts = callingModule.filename.split('/');
    return parts[parts.length - 2] + '/' + parts.pop();
};

module.exports = function (callingModule) {
    return new winston.Logger({
        transports: [
            new winston.transports.Console({
                label: getLabel(callingModule),
                json: false,
                timestamp: true,
                depth:true,
                colorize:true
            })
        ]
    });
};

现在是您的测试文件

var logger = require('./logger')(module);
function test() {
    logger.info('test logger');
}
test();

如果你运行的测试文件比输出看起来像

2017-07-08T07:15:20.671Z - info: [utils/test.js] test logger

Answer 2

由于业绩问题，温斯顿没有计划这样做。有关详细信息，请check here。

我试过了https://github.com/baryon/tracer，但这并不好，例如行号不时是不正确的。

Answer 3

更新（对于Winston 3.x）

我还创建了一个gist for the following code：

const { format } = require('winston');
const { combine, colorize, timestamp, printf } = format;

/**
 * /**
 * Use CallSite to extract filename and number, for more info read: https://v8.dev/docs/stack-trace-api#customizing-stack-traces
 * @param numberOfLinesToFetch - optional, when we want more than one line back from the stacktrace
 * @returns {string|null} filename and line number separated by a colon, if numberOfLinesToFetch > 1 we'll return a string
 * that represents multiple CallSites (representing the latest calls in the stacktrace)
 *
 */
const getFileNameAndLineNumber = function getFileNameAndLineNumber (numberOfLinesToFetch = 1) {
    const oldStackTrace = Error.prepareStackTrace;

    const boilerplateLines = line => line &&
        line.getFileName() &&
        (line.getFileName().indexOf('<My Module Name>') &&
        (line.getFileName().indexOf('/node_modules/') < 0);

    try {
        // eslint-disable-next-line handle-callback-err
        Error.prepareStackTrace = (err, structuredStackTrace) => structuredStackTrace;
        Error.captureStackTrace(this);
        // we need to "peel" the first CallSites (frames) in order to get to the caller we're looking for
        // in our case we're removing frames that come from logger module or from winston
        const callSites = this.stack.filter(boilerplateLines);
        if (callSites.length === 0) {
            // bail gracefully: even though we shouldn't get here, we don't want to crash for a log print!
            return null;
        }
        const results = [];
        for (let i = 0; i < numberOfLinesToFetch; i++) {
            const callSite = callSites[i];
            let fileName = callSite.getFileName();
            fileName = fileName.includes(BASE_DIR_NAME) ? fileName.substring(BASE_DIR_NAME.length + 1) : fileName;
            results.push(fileName + ':' + callSite.getLineNumber());
        }
        return results.join('\n');
    } finally {
        Error.prepareStackTrace = oldStackTrace;
    }
};

function humanReadableFormatter ({ level, message, ...metadata }) {
    const filename = getFileNameAndLineNumber();
    return `[${level}] [${filename}] ${message} ${JSON.stringify(metadata)}`;
}    

const logger = winston.createLogger({
  transports: [
      new winston.transports.Console({
            level: 'info',
            handleExceptions: true,
            humanReadableUnhandledException: true,
            json: false,
            colorize: { all: true },
            stderrLevels: ['error', 'alert', 'critical', 'bizAlert'],
            format: combine(
                colorize(),
                timestamp(),
                humanReadableFormatter,
            ),
        })
    ]
});

原始答案（对于Winston 2.x）

我使用的是winston 2.x（但相同的解决方案适用于winston 3.x）和that's the way我正在记录调用方的文件名和行号：

重要：请注意嵌入式代码注释！

/**
 * Use CallSite to extract filename and number
 * @returns {string} filename and line number separated by a colon
 */
const getFileNameAndLineNumber = () => {
    const oldStackTrace = Error.prepareStackTrace;
    try {
        // eslint-disable-next-line handle-callback-err
        Error.prepareStackTrace = (err, structuredStackTrace) => structuredStackTrace;
        Error.captureStackTrace(this);
        // in this example I needed to "peel" the first 10 CallSites in order to get to the caller we're looking for, hence the magic number 11
        // in your code, the number of stacks depends on the levels of abstractions you're using, which mainly depends on winston version!
        // so I advise you to put a breakpoint here and see if you need to adjust the number!
        return this.stack[11].getFileName() + ':' + this.stack[11].getLineNumber();
    } finally {
        Error.prepareStackTrace = oldStackTrace;
    }
};

以及格式化程序功能的简化版本：

function humanReadableFormatter ({level, message}) {
    const filename = getFileNameAndLineNumber();
    return `[${level}] ${filename} ${message}`;
}

然后声明要使用格式化程序的传输方式：

new winston.transports.Console({
        level: 'info',
        handleExceptions: true,
        humanReadableUnhandledException: true,
        json: false,
        colorize: 'level',
        stderrLevels: ['warn', 'error', 'alert'],
        formatter: humanReadableFormatter,
    })

要了解有关prepareStackTrace的更多信息，请阅读：https://v8.dev/docs/stack-trace-api#customizing-stack-traces

Answer 4

我在某个地方找到了此代码，是的，但是它正在工作。在新的winston.js中使用它，然后在任何文件中都需要它。

var winston = require('winston')
var path = require('path')
var PROJECT_ROOT = path.join(__dirname, '..')
var appRoot = require('app-root-path');


const options = {
  file: {
    level: 'info',
    filename: `${appRoot}/logs/app.log`,
    handleExceptions: true,
    json: true,
    maxsize: 5242880, // 5MB
    maxFiles: 5,
    colorize: false,
    timestamp: true
  },
  console: {
    level: 'debug',
    handleExceptions: true,
    json: true,
    colorize: true,
    timestamp: true
  }
};

var logger = new winston.Logger({
  transports: [
    new winston.transports.File(options.file),
    new winston.transports.Console(options.console)
  ],
  exitOnError: false // do not exit on handled exceptions
});

logger.stream = {
  write: function (message) {
    logger.info(message)
  }
}

// A custom logger interface that wraps winston, making it easy to instrument
// code and still possible to replace winston in the future.

module.exports.debug = module.exports.log = function () {
  logger.debug.apply(logger, formatLogArguments(arguments))
}

module.exports.info = function () {
  logger.info.apply(logger, formatLogArguments(arguments))
}

module.exports.warn = function () {
  logger.warn.apply(logger, formatLogArguments(arguments))
}

module.exports.error = function () {
  logger.error.apply(logger, formatLogArguments(arguments))
}

module.exports.stream = logger.stream

/**
 * Attempts to add file and line number info to the given log arguments.
 */
function formatLogArguments (args) {
  args = Array.prototype.slice.call(args)

  var stackInfo = getStackInfo(1)

  if (stackInfo) {
    // get file path relative to project root
    var calleeStr = '(' + stackInfo.relativePath + ':' + stackInfo.line + ')'

    if (typeof (args[0]) === 'string') {
      args[0] = calleeStr + ' ' + args[0]
    } else {
      args.unshift(calleeStr)
    }
  }

  return args
}

/**
 * Parses and returns info about the call stack at the given index.
 */
function getStackInfo (stackIndex) {
  // get call stack, and analyze it
  // get all file, method, and line numbers
  var stacklist = (new Error()).stack.split('\n').slice(3)

  // stack trace format:
  // http://code.google.com/p/v8/wiki/JavaScriptStackTraceApi
  // do not remove the regex expresses to outside of this method (due to a BUG in node.js)
  var stackReg = /at\s+(.*)\s+\((.*):(\d*):(\d*)\)/gi
  var stackReg2 = /at\s+()(.*):(\d*):(\d*)/gi

  var s = stacklist[stackIndex] || stacklist[0]
  var sp = stackReg.exec(s) || stackReg2.exec(s)

  if (sp && sp.length === 5) {
    return {
      method: sp[1],
      relativePath: path.relative(PROJECT_ROOT, sp[2]),
      line: sp[3],
      pos: sp[4],
      file: path.basename(sp[2]),
      stack: stacklist.join('\n')
    }
  }
}

获取日志输出的行号和文件名

4 个答案:

更新（对于Winston 3.x）

原始答案（对于Winston 2.x）