Homework & Coding Practice

Homework/Practice Coding Assignment (10-min)

Part 1: Write a Summary (5 minutes)

1. Write a one-page summary addressing the following:

   • What is the Node.js event loop, and why is it important?

   • How does Node.js manage multiple operations efficiently in a single-threaded environment?

   • Include one example of how the event loop improves application performance.

Part 2: Practice Coding

Step-by-Step Procedure with Sample Code:

1. Install Node.js:

   • Download from nodejs.org and install on your system.

   • Verify installation with:

     bash코드 복사node -v
     npm -v

2. Explore Non-Blocking I/O with setTimeout:

   • Create a file eventLoopExample.js:

     javascript코드 복사console.log('Start of the program');
     
     setTimeout(() => {
       console.log('Executed after 2 seconds');
     }, 2000);
     
     console.log('End of the program');

   • Steps:

     1. Open a terminal.

     2. Navigate to the file location.

     3. Run: node eventLoopExample.js.

   • Expected Output:

     sql코드 복사Start of the program
     End of the program
     Executed after 2 seconds

   • Key Learning Point: Node.js does not block the program while waiting for the timer.

3. Build a Simple HTTP Server:

   • Create a file server.js:

     javascript코드 복사const http = require('http');
     
     const server = http.createServer((req, res) => {
       res.writeHead(200, { 'Content-Type': 'text/plain' });
       res.end('Hello, Node.js!');
     });
     
     server.listen(3000, () => {
       console.log('Server running at http://localhost:3000/');
     });

   • Steps:

     1. Save the file.

     2. Run: node server.js.

     3. Open http://localhost:3000 in a browser.

   • Expected Output in Browser: "Hello, Node.js!"

   • Key Learning Point: Demonstrates the simplicity of creating a server using Node.js.

4. Extend the Server with Asynchronous File Reading:

   • Update server.js:

     javascript코드 복사const http = require('http');
     const fs = require('fs');
     
     const server = http.createServer((req, res) => {
       fs.readFile('example.txt', 'utf8', (err, data) => {
         if (err) {
           res.writeHead(500, { 'Content-Type': 'text/plain' });
           res.end('Error reading file');
           return;
         }
         res.writeHead(200, { 'Content-Type': 'text/plain' });
         res.end(data);
       });
     });
     
     server.listen(3000, () => {
       console.log('Server running at http://localhost:3000/');
     });

   • Create a file example.txt with sample content: "Welcome to Node.js file handling."

   • Steps:

     1. Run: node server.js.

     2. Visit http://localhost:3000.

   • Expected Output in Browser: "Welcome to Node.js file handling."

   • Key Learning Point: Understand how Node.js handles asynchronous file operations.

5. Analyze Outputs and Observations:

   • Document the order of log statements and browser outputs.

   • Relate findings to the Node.js event loop phases.

Expected Outcomes:

1. Students understand the practical application of Node.js features.

2. Hands-on exploration reinforces lecture concepts.

3. Homework ensures reflection on the event loop and its impact.