Node.js basics solution for RS School

Readme.md

@@ -1,3 +1,116 @@
-# Node.js basics
+# 🧠 Node.js Basics – Review Branch
 
-## !!! Please don't submit Pull Requests to this repository !!!
+This repository is a **review-enhanced fork** of [AlreadyBored/node-nodejs-basics](https://github.com/AlreadyBored/node-nodejs-basics), structured to align with the [RS School Node.js 2025 curriculum](https://github.com/AlreadyBored/nodejs-assignments). It includes modular implementations of core Node.js concepts, with a focus on clarity, testability, and assignment compliance.
+
+> 📌 **Branch:** `review` — 28 commits ahead, 1 behind upstream `main`
+
+---
+
+## 📚 Project Goals
+
+- Build a solid foundation in Node.js core modules and APIs
+- Practice asynchronous programming and stream handling
+- Implement CLI tools, file operations, and compression
+- Explore advanced topics like child processes and worker threads
+- Prepare for horizontal scaling with the Cluster API (Section 8)
+
+---
+
+## 📁 Folder Structure
+
+```
+src/
+├── cli/         # Command-line interface logic and argument parsing
+├── cp/          # Child process operations
+├── fs/          # File system utilities
+├── hash/        # Hashing functionality
+├── modules/     # Node.js core modules
+├── streams/     # Stream-based operations
+├── wt/          # Worker threads
+├── zip/         # Compression and decompression logic
+```
+
+Each folder corresponds to a specific RS School assignment section. All modules are self-contained and can be executed independently.
+
+---
+
+## ⚙️ Setup Instructions
+
+1. **Clone the repository**
+   ```bash
+   git clone https://github.com/toby-28/node-nodejs-basics.git
+   cd node-nodejs-basics
+   ```
+
+2. **Install dependencies**
+   ```bash
+   npm install
+   ```
+
+3. **Run a specific module**
+   ```bash
+   node src/<folder>/<file>.js
+   ```
+
+   Replace `<folder>` and `<file>` with the appropriate path. For example:
+   ```bash
+   node src/fs/files/create.js
+   ```
+
+---
+
+## 🧪 Testing
+
+Some modules include test scripts or validation logic. To run tests (if available):
+
+```bash
+npm test
+```
+
+> ✅ Ensure Node.js v18+ is installed to support modern APIs like `stream/promises` and `worker_threads`.
+
+---
+
+## 🧵 Section 8: Horizontal Scaling (Coming Soon)
+
+The `review` branch is being actively updated to include:
+- A custom load balancer using the **Cluster API**
+- Round-robin request distribution
+- Graceful worker lifecycle management
+
+Once implemented, this logic will live in a dedicated file (e.g., `src/cluster/multi.ts`) and be documented here.
+
+---
+
+## 🧠 Learning Outcomes
+
+By completing this project, you’ll gain hands-on experience with:
+
+- Node.js runtime and architecture
+- CLI tool development
+- File system and stream manipulation
+- Cryptographic hashing
+- Child processes and worker threads
+- Compression and decompression
+- Modular code organization
+- Cluster-based horizontal scaling
+
+---
+
+## 🤝 Contributing
+
+This branch is maintained for review and educational purposes. Contributions are welcome via:
+
+- Pull requests
+- Issue reports
+- Suggestions for clarity or structure
+
+---
+
+## 📄 License
+
+This project inherits the license from the original repository. See [LICENSE](https://github.com/AlreadyBored/node-nodejs-basics/blob/main/LICENSE) for details.
+
+---
+
+Made with 💡 by [@toby-28](https://github.com/toby-28) — based on the work of [@AlreadyBored](https://github.com/AlreadyBored)

src/cli/args.js

@@ -1,5 +1,10 @@
 const parseArgs = () => {
-  // Write your code here
+  const args = process.argv.slice(2);
+  for (let i = 0; i < args.length; i += 2) {
+    const key = args[i].replace(/^--/, "");
+    const value = args[i + 1];
+    console.log(`${key} is ${value}`);
+  }
 };
 
 parseArgs();

src/cli/env.js

@@ -1,5 +1,10 @@
 const parseEnv = () => {
-  // Write your code here
+  const rssVars = Object.entries(process.env)
+    .filter(([key]) => key.startsWith("RSS_"))
+    .map(([key, value]) => `${key}=${value}`)
+    .join("; ");
+
+  console.log(rssVars);
 };
 
 parseEnv();

src/cp/cp.js

@@ -1,6 +1,19 @@
-const spawnChildProcess = async (args) => {
-  // Write your code here
+import { spawn } from 'child_process';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
+export const spawnChildProcess = async (args) => {
+  const __filename = fileURLToPath(import.meta.url);
+  const __dirname = path.dirname(__filename);
+  const scriptPath = path.join(__dirname, 'files', 'script.js');
+
+  const child = spawn('node', [scriptPath, ...args], {
+    stdio: ['pipe', 'pipe', 'inherit']
+  });
+
+  process.stdin.pipe(child.stdin);
+  child.stdout.pipe(process.stdout);
 };
 
 // Put your arguments in function call to test this functionality
-spawnChildProcess( /* [someArgument1, someArgument2, ...] */);
+spawnChildProcess(['hello', 'world']);

src/fs/copy.js

@@ -1,5 +1,26 @@
+import { access, cp } from "fs/promises";
+import { constants } from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
 const copy = async () => {
-  // Write your code here
+  const dir = path.join(__dirname, "files");
+  const source = path.join(dir);
+  const destination = path.join(__dirname, "files_copy");
+
+  try {
+    await access(source, constants.F_OK);
+    await access(destination, constants.F_OK);
+    throw new Error("FS operation failed");
+  } catch (err) {
+    if (err.code === "ENOENT") {
+      await cp(source, destination, { recursive: true });
+    } else {
+      throw err;
+    }
+  }
 };
 
 await copy();

src/fs/create.js

@@ -1,5 +1,20 @@
+import { writeFile, access } from "fs/promises";
+import { constants } from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
 const create = async () => {
-  // Write your code here
+  const dir = path.join(__dirname, "files");
+  const filePath = path.join(dir, "fresh.txt");
+
+  try {
+    await access(filePath, constants.F_OK);
+    throw new Error("FS operation failed");
+  } catch {
+    await writeFile(filePath, "I am fresh and young", { flag: "wx" });
+  }
 };
 
 await create();

src/fs/delete.js

@@ -1,5 +1,20 @@
+import { unlink, access } from "fs/promises";
+import { constants } from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
 const remove = async () => {
-  // Write your code here
+  const dir = path.join(__dirname, "files");
+  const filePath = path.join(dir, "fileToRemove.txt");
+
+  try {
+    await access(filePath, constants.F_OK);
+    await unlink(filePath);
+  } catch {
+    throw new Error("FS operation failed");
+  }
 };
 
 await remove();

src/fs/list.js

@@ -1,5 +1,21 @@
+import { readdir, access } from "fs/promises";
+import { constants } from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
 const list = async () => {
-  // Write your code here
+  const dir = path.join(__dirname, "files");
+  const dirPath = path.join(dir);
+
+  try {
+    await access(dirPath, constants.F_OK);
+    const files = await readdir(dirPath);
+    console.log(files);
+  } catch {
+    throw new Error("FS operation failed");
+  }
 };
 
 await list();

src/fs/read.js

@@ -1,5 +1,21 @@
+import { readFile, access } from "fs/promises";
+import { constants } from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
 const read = async () => {
-  // Write your code here
+  const dir = path.join(__dirname, "files");
+  const filePath = path.join(dir, "fileToRead.txt");
+
+  try {
+    await access(filePath, constants.F_OK);
+    const content = await readFile(filePath, "utf-8");
+    console.log(content);
+  } catch {
+    throw new Error("FS operation failed");
+  }
 };
 
 await read();

src/fs/rename.js

@@ -1,5 +1,26 @@
-const rename = async () => {
-  // Write your code here
+import { rename, access } from "fs/promises";
+import { constants } from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
+const renameFile = async () => {
+  const dir = path.join(__dirname, "files");
+  const oldPath = path.join(dir, "wrongFilename.txt");
+  const newPath = path.join(dir, "properFilename.md");
+
+  try {
+    await access(oldPath, constants.F_OK);
+    await access(newPath, constants.F_OK);
+    throw new Error("FS operation failed");
+  } catch (err) {
+    if (err.code === "ENOENT") {
+      await rename(oldPath, newPath);
+    } else {
+      throw err;
+    }
+  }
 };
 
-await rename();
+await renameFile();

src/hash/calcHash.js

@@ -1,5 +1,27 @@
-const calculateHash = async () => {
-  // Write your code here
+import { createHash } from "crypto";
+import { createReadStream } from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const calcHash = async () => {
+  const __filename = fileURLToPath(import.meta.url);
+  const __dirname = path.dirname(__filename);
+  const filePath = path.join(__dirname, "files", "fileToCalculateHashFor.txt");
+
+  const hash = createHash("sha256");
+  const stream = createReadStream(filePath);
+
+  stream.on("error", () => {
+    console.error("FS operation failed");
+  });
+
+  stream.on("data", (chunk) => {
+    hash.update(chunk);
+  });
+
+  stream.on("end", () => {
+    console.log(hash.digest("hex"));
+  });
 };
 
-await calculateHash();
+await calcHash();