Node-Intro1.md

Node 2 hour course

Agenda

• 0:00 - 0:05 Course Outline

• 0:05 - 0:30 Discussion - What Is Node, Really ?

• 0:30 - 0:55 Micro-challenges and review

• 0:55 - 1:00 Break

• 1:00 - 1:50 Labs - Learnyounode

• 1:50 - 2:00 Review

• NodeJS Resources

  • http://nodejs.org/
  • http://www.nodebeginner.org/

• Technological Backgrounds

  • Google V8 Javascript Engine
  • Javascript - essentially evented
  • NodeJS != express - Modularity via Packages

• General Capabilities

  • Speed
  • Database (mysql, mongo, etc..), other I/O bound tasks
  • NOT large amounts of computation

• Fundamental Concepts

  • being bound (IO, CPU, etc..)
  • Eventedness
  • Concurrency - Threads vs. Processes vs. Event Loop
  • Callstacks
  • Function passing
  • setTimeOut - throw a task into the future (and while waiting, wha???)

• Learn you node

  • npm install -g learnyounode

• Props (credits)

  • http://debuggable.com/posts/understanding-node-js:4bd98440-45e4-4a9a-8ef7-0f7ecbdd56cb
  • http://www.stepneyct.org/history/ht/images/stop_17e_430x195.jpg
  • http://www.slideshare.net/marcusf/nonblocking-io-event-loops-and-nodejs

Micro-challenges :

1. Deferred Execution (Browser or Node)

console.log("Hello from Node")

// defer the execution of this
console.log("Goodbye from Node")

// and let this run right away
console.log("Hangin' with Node")

2. Delegated Execution

function say(word) {
  console.log(word);
}

// write a function execute which enables the following
execute(say, "Hello");

3. Input/Output Node-Style

var fs = require('fs');

// turn this pseudo-code into real code
//
// contents = fs.readFile('somefile.txt') 
// console.log("Look at all my money: " + contents);
//
// Hint: lookup the docs for fs.readFile and compare fs.readFileSync

4. Mini Web Server

var http = require("http");

function onRequest(request, response) {
  console.log("Request received.");
  response.writeHead(200, {"Content-Type": "text/plain"});
  response.write("Hello World");
  response.end();
}

http.createServer(onRequest).listen(8888);

console.log("Server has started.");
// test with browser or
// curl -v http://127.0.0.1:8888/
// ab -n 1000 -c 200 http://127.0.0.1:8888/