Narasimha9271/Building-Express

Phase-1

• In App.js -> Application object is where our main functions like get, use going to reside.
• The methods library just returns all the http methods in lowercase.
• this.lazyrouter() -- which means for the given application we are going to create an Router.
  Router.js

  Going to handle the routing logic. Only one per application.

• The important properties of an router is its stack.
• our router - which internally has stack to keep our routes inclined. We need to expose a function, so that user can add specific routes into the stack. This function is called as route.
• For a given path (a route actually) we are creating a Route and a Layer.
• The layer contains the route. Layer also takes few properties.
• After creating the route and layer, we are pushing the data into the routers stack.
  Route.js

  Going to hold information about the route and the layer, which has the handles for a given path.

• Layer -> Contains the path and necessary function reference to execute when a path matches the given request.

Phase-3 - next()

• The next() function is used to pass the control to the next middleware function.

app.get("/route1", (req, res, next) => {
    console.log("came here");
    next();
});

app.get("/route1", (req, res) => {
    res.writeHead(200);
    res.write(`hello world`);
    res.end();
});

• here after hitting /route1 -> firstly came here is printed them it goes call next()middleware means goes to next same route and execute them.
• when you call next from your callback, its gonna resume the processing of stack from where it stopped.