Next() :

• it is a callback function in a middleware
• it passses the control to the subsequent function
• if next () is missed, the control flow will hang

Route based Middlewares

Global Middlewares

• manages the flow of control
• code reusability esp for restrivted routes

• sit between your router and your HANDLER

router.post('/getHomePage' , MiddlewareIfLoggedIn, UserController.homePage)

function MiddlewareIfLoggedIn( req, res, next) { if loggedIn then call the next fucntion/handler which will give us the home page feeds else res.send( " please login or register") }

restricted API's

router.get('/homePage', mid1, UserController.feeds) router.get('/profileDetails', mid1, UserController.profileDetails) router.get('/friendList', mid1, UserController.friendList) router.get('/changePassword', mid1, UserController.changePassword)

OPen-to-all API's

router.get('/termsAndConditions', UserController.termsAndConditions) router.get('/register', UserController.register)

app.use( midGlobal)

body-parser functions:

• getting the post data in req.body
• getting the req.body data as JSON
• providing the header data in req.header etc etc

you punch your userName and password if correct you get loggedIn...

next time you call an api to get your FB friendList..FB should ask you for a login again ( BUT this does not happen in real life)

after 30 mins..you try to access your profile page..ideally FB should ask you to login again..BUT this does not happen in real life

you punch your userName and password ..FB will craete a unique secret token( unique to every user) and send it to the browser..Chrome will save this token in its storage next time I want to acess my friendList..chrome(frontend) will send this token ( already stored in chrome storage) to the API..this API will first call a Middleware which will verify if the token is correct and who does it belong to..if token is correct then we will send the friend list of the concerned person..else send not authorised

next time when you request your profile page..token is checked ..if correct you get your profile page, else "not authorised"

intro

Write a middleware that logs (console.log) some data everytime any API is hit Data to be logged:-the current timestamp(as date time) , the IP of the user and the route being requested). For this first figure out how to get the route location being requested, how to get current timestamp and how to get the IP. NOTE: ip of local computer will come as ::1 so dont get disturbed by seeing this)

e.g: you should be logging something like this on each line: time , IP, Route should be printed on each line in terminal( every time an api is hit) 2010-08-19 14:00:00 , 123.459.898.734 , /createUser 2010-08-19 14:00:00 , 123.459.898.734 , /basicAPi 2010-08-19 14:00:00 , 123.459.898.734 , /falanaAPI