Console.log is my friend (yours, too)

I don’t get to use a lot of JavaScript at this point in my new job, so to keep up on my JS skillz I spend some of my weekend time practicing old things or learning new things. Right now I’m learning Node. And while reading some code for a basic Express server, I was reminded of the lovely thing that is console.log.

Here’s the code:


var express = require('express')
var app = express()

var jsonData = {count: 12, message: 'hey'}

app.get('/', function(req, res){
  res.sendFile(__dirname + '/index.html', function(err) {
    if (err) {
      res.status(500).send(err)
    }
  })
})

app.get('/data', function(req, res) {
  res.json(jsonData)
});

var port = 3000
app.listen(port, function(){
  console.log('listening on http://localhost:', port)
})

I can see the code is pulling in Express, that it’s declaring a jsonData variable and assigning an object to it, that the get method will call one of two functions depending on the path that’s being requested, and that the listen method will show me what’s happening on my localhost:3000. And I can see those two get functions are going to use req and res, and I can see what happens with res…but what about req? I figure it’s the request coming in, but I have this need to know what all parts of all things look like, so how do I find out? Put a console.log in those functions, of course! It’s about a gazillion lines of data so I won’t repost it all here but at the very bottom, I see something like this for the first get function when I ask for the root path(‘/’):


route: Route { path: '/', stack: [ [Object] ], methods: { get: true } } }

And something like this for the second get function when I ask for the data path (‘/data’):


route: Route { path: '/data', stack: [ [Object] ], methods: { get: true } } }

Doing things like this helps the code make more sense in my brain. While I understood that the functions were taking in requests and returning responses, now I can see what the requests actually look like and I can see how the functions are seeing the path. Yay!

Author: Ashly

I like learning, food, travel, and sports, and I love Salt Lake City.