Allows to trace HTTP/HTTPs requests in Express by appending traceIds to request header.

$ npm install --save request-tracer

var express = require('express');
var requestTracer = require('request-tracer');

var tracerListener = requestTracer({ router: express.Router() });

tracerListener.on('newProcess', function(traceProcessId) {
  console.log('New process[%s] with configuration', traceProcessId);
});

tracerListener.on('newSession', function(id, traceProcessId) {
  console.log('New session[%s] in process[%s]', id, traceProcessId);
});

tracerListener.on('newRequest', function(id, traceSessionId) {
  console.log('New request[%s] in session[%s]', id, traceSessionId);
});

var app = express();
app.use(tracerListener.interceptor());

// ...

app.use(function(req, res, next) {
  console.log(' - traceProcessId: %s', req.traceProcessId);
  console.log(' - traceSessionId: %s', req.traceSessionId);
  console.log(' - traceRequestId: %s', req.traceRequestId);
  next();
});