Express quick start

Created: 2020-09-30 21:02:24 -0700 Modified: 2020-09-30 21:09:55 -0700

Background

§Section titled Background

This note is just for me to remember how to set up a really quick web server that can run JavaScript on the server based on a client’s request.

1. Follow the getting-started guide
   1. It’s pretty much the following:
   2. yarn init -y
   3. yarn add express
   4. npx express-generator
2. Write your code in whatever file you want, e.g. serverside.js. Make sure to export functions that you want to use.
3. Add this code to app.js:

const runCommand = require("./serverside.js");

app.get("/command/:num", (req, res) => {
  runCommand(req.params.num);
  res.sendStatus(200);
});

4. Make index.jade look something like this:

extends layout

block content
  script.
    function runCommand(num) {
      var xhttp = new XMLHttpRequest();
      xhttp.open("GET", "/command/" + num, true);
      xhttp.send();
    }

  button(onclick='runCommand(1)') Command 1
  button(onclick='runCommand(5)') Command 5

5. Start the server with something like this:

sudo PORT=80 DEBUG=light-server:* npm start