req params vs req query vs req body code example
Example 1: difference between req.query and req.params
req.params contains route parameters
(in the path portion of the URL),
and req.query contains the URL query parameters
(after the ? in the URL).
You can also use req.param(name) to look up a parameter in both places
(as well as req.body),
but this method is now deprecated.
Example 2: req.params vs req.body
* req.user: object make by passport.js added to req that include a username and user id
* req.params: from path segments of URL that match a route definition parameter
* /song/:id
* req.body: hold parameters sent by post request (like form data)