I am using winston logger. I want to add uuid in every logs having same uuid per request.
In app.js
var distributorapp = require('./routes/distributorapp');
app.use('/dstapp',distributorapp);
In routes/distributorapp.js(Middleware)
var qs = require('querystring');
var request = require('request');
var logger = require('../locallibs/logger');
var uuid = require('uuid/v1');
module.exports = {
mddlw: function (req, res, next) {
req.bodyData = qs.parse(req.body); // parsing body and added to request object
req.uuid = uuid(); // Adding uuid to request to available every where throught request
callHsmRest(req, res); // function to do some logic and handle middleware functionality
}
};
In logger.js
var winston = require('winston');
var fs = require('fs');
var moment = require('moment');
var today = moment().format('YYYY-MM-DD');
if (!fs.existsSync(today)) {
fs.mkdirSync(today);
}
function customFileFormatter(options) {
console.log(options);
return options.timestamp() + ' [' + options.level.toUpperCase() + '] ' + (undefined !== options.message ? options.message : '') +
(options.meta && Object.keys(options.meta).length ? JSON.stringify(options.meta) : '');
}
var logger = new (winston.Logger)({
transports: [
new (winston.transports.File)({
timestamp: function () {
return moment().format();
},
json: false,
filename: today + '/test.log',
formatter: customFileFormatter
})
]
});
Now in every request I want to generate uuid and add it to request body.So I have added in Middleware.But how it will be available to logger.js in customFileFormatter formatter function?
When some one uses this logger to log any data i want that uuid to be prepended in logger formatter in every logs through request.
If some one require logger.js
and do
logger.info("Hello");
logger.info("Hi");
Currently following I have following logs
2017-02-24T12:36:23+05:30 [INFO] "Hello"
2017-02-24T12:36:23+05:30 [INFO] "Hi"
But I want
2017-02-24T12:36:23+05:30 [INFO] c00d6800-fa5f-11e6-83c2-f531bfc95472 "Hello"
2017-02-24T12:36:23+05:30 [INFO] c00d6800-fa5f-11e6-83c2-f531bfc95472 "Hi"
Also I want to change logger file path according to route middleware.
Currently when request came from /dstapp
it uses distributorapp
Middleware and every subsequent logs from this request goes to path dstapp/2017-02-24/test.log
But when request came from lets say /anotherapp
it uses anotherapp
Middleware and subsequent logs from this request goes to path anotherapp/2017-02-24/test.log
I have searched through every where but can't find any solution Thanks in Advance
I had to face this same problem. I found out a solution using node-uuid library to generate a unique uuid for each request, and continuation-local-storage library to share information among modules.
1º. I added a middleware functionality to create the uuid for each request and add it to the namespace I had created:
var uuid = require('node-uuid');
var createNamespace = require('continuation-local-storage').createNamespace;
var myRequest = createNamespace('my request');
// Run the context for each request. Assign a unique identifier to each request
app.use(function(req, res, next) {
myRequest.run(function() {
myRequest.set('reqId', uuid.v1());
next();
});
});
2º. I wrapped winston library to print get the id of the request and add it to every log, something like this:
var winston = require('winston');
var getNamespace = require('continuation-local-storage').getNamespace;
// Wrap Winston logger to print reqId in each log
var formatMessage = function(message) {
var myRequest = getNamespace('my request');
message = myRequest && myRequest.get('reqId') ? message + " reqId: " + myRequest.get('reqId') : message;
return message;
};
var logger = {
log: function(level, message) {
winstonLogger.log(level, formatMessage(message));
},
error: function(message) {
winstonLogger.error(formatMessage(message));
},
warn: function(message) {
winstonLogger.warn(formatMessage(message));
},
verbose: function(message) {
winstonLogger.verbose(formatMessage(message));
},
info: function(message) {
winstonLogger.info(formatMessage(message));
},
debug: function(message) {
winstonLogger.debug(formatMessage(message));
},
silly: function(message) {
winstonLogger.silly(formatMessage(message));
}
};
module.exports = logger;
With this 2 pieces of code you get it.
To make it easier, I created a library that implements all this, and you can use it as winston, without being worried about all this stuff: https://github.com/davicente/express-logger-unique-req-id
If you want to get into it a little bit more, you can take a look to this article: https://solidgeargroup.com/express-logging-global-unique-request-identificator-nodejs