Introduction to Node.js prework

Intro-To-Node.md

const http = require('http');
const url = require('url');
const server = http.createServer();

let messages = [
  { 'id': 1, 'user': 'Jason Hughes', 'message': 'hi there!' },
  { 'id': 2, 'user': 'Bob Loblaw', 'message': 'check out my law blog' },
  { 'id': 3, 'user': 'Lorem Ipsum', 'message': 'dolor set amet' }
];

server.listen(3000, () => {
  console.log('The HTTP server is listening at Port 3000.');
});

server.on('request', (request, response) => {
  if (request.method === 'GET') {
    getAllMessages(response);
  }

  else if (request.method === 'POST') {
    let newMessage = { 'id': new Date(),
                     'user': 'alex trebek',
                  'message': 'answer in the form of a question'
  };

    request.on('data', (data) => {
      newMessage = Object.assign(newMessage,
      JSON.parse(data));
    });

    request.on('end', () => {
      addMessage(newMessage, response);
    });
  }
});

const getAllMessages = (response) => {
  response.writeHead(200, {
    'Content-Type': 'application/json'
  });
  response.write(JSON.stringify(messages));
  response.end();
}

const addMessage = (newMessage, response) => {
  messages.push(newMessage);
  response.writeHead(201, {
    'Content-Type': 'application/json'
  });
  response.write(JSON.stringify(messages));
  response.end()
}

Checks for Understanding

1. What type of information is included in the header of a request?

• Information that defines the operating parameters of an HTTP transaction.
• Examples of HTTP header information includes:
  • RESTful method
  • HTTP version
  • User Agent
  • Content-Types
  • Acceptable encoding, language, charset, etc.

2. What are the major RESTful methods and what do each of them do?

• GET - Retrieves the resource info sent by the request.
• POST - Creates a new resource.
• PUT - Update an entire resource.
• PATCH - Updates only portion of a resource.
• DELETE - Delete an entire specific resource by the request.

3. What is Node?

• Node is an open-source server framework that allows us to apply JS skills outside of the browser. It was built to make asynchronous I/O easier. It is an event-driven and non-blocking model.