const express = require('express');
const pino = require('pino');
const {wrapLogger, addContext} = require('pino-context');
const expressScopeMiddleware = require('pino-context/integrations/express');
const logger = wrapLogger(pino());
const app = express();

app.use(expressScopeMiddleware());

app.use((req, res, next) => {
  addContext('requestId', 'unique identifier'); // Generate some unique identifier
  next();
});

app.use((req, res, next) => {
  logger.info('This is a log');
  next();
});

app.use((req, res, next) => {
  addContext('url', req.url);
  next();
});

app.get('/', (req, res) => {
  logger.info('This is another log');
  res.send(`Hello World`);
});

app.listen(1337, () => {
  logger.info('Listening');
});

{"level":30,"time":1551190582956,"msg":"Listening","pid":13031,"context":{},"v":1}
{"level":30,"time":1551190586342,"msg":"This is a log","pid":13031,"context":{"requestId":"unique identifier"},"v":1}
{"level":30,"time":1551190586342,"msg":"This is another log","pid":13031,"context":{"requestId":"unique identifier","url":"/"},"v":1}