[assignments] Complete assignment 1

assignment1/async-demo.js

@@ -1,16 +1,29 @@
-const fs = require('fs');
-const path = require('path');
+const fs = require('node:fs');
+const path = require('node:path');
 
+const CONTENT_STRING = 'Hello, async world!';
 
 // Write a sample file for demonstration
+const filePath = path.join(__dirname, 'sample-files', 'sample.txt');
 
-// 1. Callback style
-
-
-  // Callback hell example (test and leave it in comments):
-
+const main = async () => {
+  // 1. Callback style
+  console.log('Callback read:', CONTENT_STRING);
+  fs.writeFileSync(filePath, CONTENT_STRING);
 
   // 2. Promise style
-
-
-      // 3. Async/Await style
+  console.log('Promise read:', CONTENT_STRING);
+  fs.promises
+    .writeFile(filePath, CONTENT_STRING)
+    .catch((err) => console.error('Error writing file with promises:', err));
+
+  // 3. Async/Await style
+  try {
+		console.log('Async/Await read:', CONTENT_STRING);
+    await fs.promises.writeFile(filePath, CONTENT_STRING);
+  } catch (err) {
+    console.error('Error writing file with async/await:', err);
+  }
+};
+
+main();

assignment1/core-modules-demo.js

@@ -1,18 +1,42 @@
-const os = require('os');
-const path = require('path');
-const fs = require('fs');
+const fs = require('node:fs');
+const os = require('node:os');
+const path = require('node:path');
 
 const sampleFilesDir = path.join(__dirname, 'sample-files');
 if (!fs.existsSync(sampleFilesDir)) {
   fs.mkdirSync(sampleFilesDir, { recursive: true });
 }
 
-// OS module
+const main = async () => {
+  // OS module
+  console.log(`Platform: ${os.platform()}`);
+  console.log(`CPU: ${os.cpus()[0].model}`);
+  console.log(`Total Memory: ${os.totalmem()}`);
 
+  const demoTextFilePath = path.join(sampleFilesDir, 'demo.txt');
+  // Path module
+  console.log('Joined path:', demoTextFilePath);
 
-// Path module
+  // fs.promises API
+  await fs.promises.writeFile(demoTextFilePath, 'Hello from fs.promises!');
+	console.log('fs.promises read:', await fs.promises.readFile(demoTextFilePath, 'utf8'));
 
-// fs.promises API
+  // Streams for large files- log first 40 chars of each chunk
+  // 1. Create a large file for demonstration
+  const largeFilePath = path.join(sampleFilesDir, 'largefile.txt');
+  if (!fs.existsSync(largeFilePath)) {
+    const largeContent = 'A'.repeat(10 * 1024); // Lots of 'A'
+    fs.writeFileSync(largeFilePath, largeContent);
+  }
 
+	// 2. Read the large file using streams
+	const readStream = fs.createReadStream(largeFilePath, { encoding: 'utf8' });
+	readStream.on('data', (chunk) => {
+		console.log('Read chunk:', chunk.slice(0, 40)); // Log first 40 chars of each chunk
+	});
+	readStream.on('end', () => {
+		console.log('Finished reading large file with streams');
+	});
+};
 
-// Streams for large files- log first 40 chars of each chunk
+main();

assignment1/globals-demo.js

@@ -1,7 +1,7 @@
-// Log __dirname and __filename
+console.log('__dirname:', __dirname);
+console.log('__filename:', __filename);
+console.log('Process ID:', process.pid);
+console.log('Platform:', process.platform);
 
-
-// Log process ID and platform
-
-
-// Attach a custom property to global and log it
+globalThis.myCustomVar = 'Hello, global!';
+console.log('Custom global variable:', globalThis.myCustomVar);