express-winston

express.js middleware for flatiron/winston

express-winston

winston middleware for express.js

npm install express-winston

If you're already using express-winston, and want to stick with the stable version based on winston 0.9.x, you should instead do:

npm install express-winston@0.x.x --save

express-winston provides middlewares for request and error logging of your express.js application. It uses 'whitelists' to select properties from the request and (new in 0.2.x) response objects.

To make use of express-winston, you need to add the following to your application:

In package.json:

{
  "dependencies": {
    "...": "...",
    "winston": "0.6.x",
    "express-winston": "0.2.x",
    "...": "..."
  }
}

In server.js (or wherever you need it):

var winston = require('winston'),
    expressWinston = require('express-winston');

Use expressWinston.errorLogger(options) to create a middleware that log the errors of the pipeline.

    var router = require('./my-express-router');
 
    app.use(router); // notice how the router goes first. 
    app.use(expressWinston.errorLogger({
      transports: [
        new winston.transports.Console({
          json: true,
          colorize: true
        })
      ]
    }));

The logger needs to be added AFTER the express router(app.router)) and BEFORE any of your custom error handlers(express.handler). Since express-winston will just log the errors and not handle them, you can still use your custom error handler like express.handler, just be sure to put the logger before any of your handlers.

    transports: [<WinstonTransport>], // list of all winston transports instances to use. 
    winstonInstance: <WinstonLogger>, // a winston logger instance. If this is provided the transports option is ignored 
    level: String, // log level to use, the default is "info". 
    statusLevels: Boolean // different HTTP status codes caused log messages to be logged at different levels (info/warn/error), the default is false 
    skipfunction(reqres) // function to determine if logging is skipped, defaults to false 

To use winston's existing transports, set transports to the values (as in key-value) of the winston.default.transports object. This may be done, for example, by using underscorejs: transports: _.values(winston.default.transports).

Alternatively, if you're using a winston logger instance elsewhere and have already set up levels and transports, pass the instance into expressWinston with the winstonInstance option. The transports option is then ignored.

Use expressWinston.logger(options) to create a middleware to log your HTTP requests.

    var router = require('./my-express-router');
 
    app.use(expressWinston.logger({
      transports: [
        new winston.transports.Console({
          json: true,
          colorize: true
        })
      ],
      meta: true, // optional: control whether you want to log the meta data about the request (default to true) 
      msg: "HTTP {{req.method}} {{req.url}}", // optional: customize the default logging message. E.g. "{{res.statusCode}} {{req.method}} {{res.responseTime}}ms {{req.url}}" 
      expressFormat: true, // Use the default Express/morgan request formatting, with the same colors. Enabling this will override any msg and colorStatus if true. Will only output colors on transports with colorize set to true 
      colorStatus: true, // Color the status code, using the Express/morgan color palette (default green, 3XX cyan, 4XX yellow, 5XX red). Will not be recognized if expressFormat is true 
      ignoreRoutefunction (reqres) { return false; } // optional: allows to skip some log messages based on request and/or response 
    }));
 
    app.use(router); // notice how the router goes after the logger. 
    var express = require('express');
    var expressWinston = require('express-winston');
    var winston = require('winston'); // for transports.Console 
    var app = module.exports = express();
 
    app.use(express.bodyParser());
    app.use(express.methodOverride());
 
    // Let's make our express `Router` first. 
    var router = express.Router();
    router.get('/error', function(reqresnext) {
      // here we cause an error in the pipeline so we see express-winston in action. 
      return next(new Error("This is an error and it should be logged to the console"));
    });
 
    app.get('/', function(reqresnext) {
      res.write('This is a normal request, it should be logged to the console too');
      res.end();
    });
 
    // express-winston logger makes sense BEFORE the router. 
    app.use(expressWinston.logger({
      transports: [
        new winston.transports.Console({
          json: true,
          colorize: true
        })
      ]
    }));
 
    // Now we can tell the app to use our routing code: 
    app.use(router);
 
    // express-winston errorLogger makes sense AFTER the router. 
    app.use(expressWinston.errorLogger({
      transports: [
        new winston.transports.Console({
          json: true,
          colorize: true
        })
      ]
    }));
 
    // Optionally you can include your custom error handler after the logging. 
    app.use(express.errorLogger({
      dumpExceptions: true,
      showStack: true
    }));
 
    app.listen(3000, function(){
      console.log("express-winston demo listening on port %d in %s mode", this.address().port, app.settings.env);
    });

Browse / to see a regular HTTP logging like this:

{
  "req": {
    "httpVersion": "1.1",
    "headers": {
      "host": "localhost:3000",
      "connection": "keep-alive",
      "accept": "*/*",
      "user-agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_4) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11",
      "accept-encoding": "gzip,deflate,sdch",
      "accept-language": "en-US,en;q=0.8,es-419;q=0.6,es;q=0.4",
      "accept-charset": "ISO-8859-1,utf-8;q=0.7,*;q=0.3",
      "cookie": "connect.sid=nGspCCSzH1qxwNTWYAoexI23.seE%2B6Whmcwd"
    },
    "url": "/",
    "method": "GET",
    "originalUrl": "/",
    "query": {}
  },
  "res": {
    "statusCode": 200
  },
  "responseTime" : 12,
  "level": "info",
  "message": "HTTP GET /favicon.ico"
}

Browse /error will show you how express-winston handles and logs the errors in the express pipeline like this:

{
  "date": "Thu Jul 19 2012 23:39:44 GMT-0500 (COT)",
  "process": {
    "pid": 35719,
    "uid": 501,
    "gid": 20,
    "cwd": "/Users/thepumpkin/Projects/testExpressWinston",
    "execPath": "/usr/local/bin/node",
    "version": "v0.6.18",
    "argv": [
      "node",
      "/Users/thepumpkin/Projects/testExpressWinston/app.js"
    ],
    "memoryUsage": {
      "rss": 14749696,
      "heapTotal": 7033664,
      "heapUsed": 5213280
    }
  },
  "os": {
    "loadavg": [
      1.95068359375,
      1.5166015625,
      1.38671875
    ],
    "uptime": 498086
  },
  "trace": [
    ...,
    {
      "column": 3,
      "file": "Object].log (/Users/thepumpkin/Projects/testExpressWinston/node_modules/winston/lib/winston/transports/console.js",
      "function": "[object",
      "line": 87,
      "method": null,
      "native": false
    }
  ],
  "stack": [
    "Error: This is an error and it should be logged to the console",
    "    at /Users/thepumpkin/Projects/testExpressWinston/app.js:39:15",
    "    at callbacks (/Users/thepumpkin/Projects/testExpressWinston/node_modules/express/lib/router/index.js:272:11)",
    "    at param (/Users/thepumpkin/Projects/testExpressWinston/node_modules/express/lib/router/index.js:246:11)",
    "    at pass (/Users/thepumpkin/Projects/testExpressWinston/node_modules/express/lib/router/index.js:253:5)",
    "    at Router._dispatch (/Users/thepumpkin/Projects/testExpressWinston/node_modules/express/lib/router/index.js:280:4)",
    "    at Object.handle (/Users/thepumpkin/Projects/testExpressWinston/node_modules/express/lib/router/index.js:45:10)",
    "    at next (/Users/thepumpkin/Projects/testExpressWinston/node_modules/express/node_modules/connect/lib/http.js:204:15)",
    "    at done (/Users/thepumpkin/Dropbox/Projects/express-winston/index.js:91:14)",
    "    at /Users/thepumpkin/Dropbox/Projects/express-winston/node_modules/async/lib/async.js:94:25",
    "    at [object Object].log (/Users/thepumpkin/Projects/testExpressWinston/node_modules/winston/lib/winston/transports/console.js:87:3)"
  ],
  "req": {
    "httpVersion": "1.1",
    "headers": {
      "host": "localhost:3000",
      "connection": "keep-alive",
      "cache-control": "max-age=0",
      "user-agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_4) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11",
      "accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
      "accept-encoding": "gzip,deflate,sdch",
      "accept-language": "en-US,en;q=0.8,es-419;q=0.6,es;q=0.4",
      "accept-charset": "ISO-8859-1,utf-8;q=0.7,*;q=0.3",
      "cookie": "connect.sid=nGspCCSzH1qxwNTWYAoexI23.seE%2B6WhmcwdzFEjqhMDuIIl3mAUY7dT4vn%2BkWvRPhZc"
    },
    "url": "/error",
    "method": "GET",
    "originalUrl": "/error",
    "query": {}
  },
  "level": "error",
  "message": "middlewareError"
}

Express-winston exposes three whitelists that control which properties of the request, body, and response are logged:

  • requestWhitelist
  • bodyWhitelist, bodyBlacklist
  • responseWhitelist

For example, requestWhitelist defaults to:

['url', 'headers', 'method', 'httpVersion', 'originalUrl', 'query'];

Only those properties of the request object will be logged. Set or modify the whitelist as necessary.

For example, to include the session property (the session data), add the following during logger setup:

expressWinston.requestWhitelist.push('session');

The blacklisting excludes certain properties and keeps all others. If both bodyWhitelist and bodyBlacklist are set the properties excluded by the blacklist are not included even if they are listed in the whitelist!

Example:

expressWinston.bodyBlacklist.push('secretid', 'secretproperty');

Note that you can log the whole request and/or response body:

expressWinston.requestWhitelist.push('body');
expressWinston.responseWhitelist.push('body');

New in version 0.2.x is the ability to add whitelist elements in a route. express-winston adds a _routeWhitelists object to the request, containing .body, .req and .res` properties, to which you can set an array of 'whitelist' parameters to include in the log, specific to the route in question:

    router.post('/user/register', function(reqresnext) {
      req._routeWhitelists.body = ['username', 'email', 'age']; // But not 'password' or 'confirm-password' or 'top-secret' 
      req._routeWhitelists.res = ['_headers'];
    });

Post to /user/register would give you something like the following:

{
  "req": {
    "httpVersion": "1.1",
    "headers": {
      "host": "localhost:3000",
      "connection": "keep-alive",
      "accept": "*/*",
      "user-agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_4) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11",
      "accept-encoding": "gzip,deflate,sdch",
      "accept-language": "en-US,en;q=0.8,es-419;q=0.6,es;q=0.4",
      "accept-charset": "ISO-8859-1,utf-8;q=0.7,*;q=0.3",
      "cookie": "connect.sid=nGspCCSzH1qxwNTWYAoexI23.seE%2B6Whmcwd"
    },
    "url": "/",
    "method": "GET",
    "originalUrl": "/",
    "query": {},
    "body": {
      "username": "foo",
      "email": "foo@bar.com",
      "age": "72"
    }
  },
  "res": {
    "statusCode": 200
  },
  "responseTime" : 12,
  "level": "info",
  "message": "HTTP GET /favicon.ico"
}

Blacklisting supports only the body property.

    router.post('/user/register', function(reqresnext) {
      req._routeWhitelists.body = ['username', 'email', 'age']; // But not 'password' or 'confirm-password' or 'top-secret' 
      req._routeBlacklists.body = ['username', 'password', 'confirm-password', 'top-secret'];
      req._routeWhitelists.res = ['_headers'];
    });

If both req._bodyWhitelist.body and req._bodyBlacklist.body are set the result will be the white listed properties excluding any black listed ones. In the above example, only 'email' and 'age' would be included.

Run the basic Mocha tests:

npm test

Run the Travis-CI tests (which will fail with < 100% coverage):

npm test-travis

Generate the coverage.html coverage report:

npm test-coverage

If you ran into any problems, please use the project Issues section to search or post any bug.

Also see AUTHORS file, add yourself if you are missing.

Copyright (c) 2012-2014 Bithavoc.io and Contributors - http://bithavoc.io

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.