feat: add read/written bytes from/to request/response

Based on `count-response-size-middleware`.

lib/middlewares/addRWBytes.js

@@ -0,0 +1,15 @@
+const addRWBytes = () => (req, res, next) => {
+  const handle = () => {
+    res.removeListener('finish', handle)
+    res.removeListener('close', handle)
+    res.bytesRead = req.connection.bytesRead
+    res.bytesWritten = req.connection.bytesWritten
+  }
+
+  res.on('finish', handle)
+  res.on('close', handle)
+
+  next()
+}
+
+module.exports = addRWBytes

lib/routes.js

@@ -7,10 +7,11 @@ const nocache = require('nocache')
 
 const logger = require('./logger')
 
+const addRWBytes = require('./middlewares/addRWBytes')
 const authorize = require('./middlewares/authorize')
+const computeSchema = require('./middlewares/compute-schema')
 const errorHandler = require('./middlewares/errorHandler')
 const filterOldRequests = require('./middlewares/filterOldRequests')
-const computeSchema = require('./middlewares/compute-schema')
 const findOperatorId = require('./middlewares/operatorId')
 const populateDeviceId = require('./middlewares/populateDeviceId')
 const populateSettings = require('./middlewares/populateSettings')
@@ -50,6 +51,7 @@ const configRequiredRoutes = [
 ]
 
 // middleware setup
+app.use(addRWBytes())
 app.use(compression({ threshold: 500 }))
 app.use(helmet())
 app.use(nocache())