Node.js basics

Readme.md

@@ -1,3 +1,3 @@
 # Node.js basics
 
-## !!! Please don't submit Pull Requests to this repository !!!
+## This is brunch with completed tasks

src/cli/args.js

@@ -1,5 +1,16 @@
 const parseArgs = () => {
-    // Write your code here 
+    const argsArr = process.argv.slice(2);
+    const argsObj = {};
+
+    for (let i = 0; i < argsArr.length; i += 2) {
+        argsObj[argsArr[i].slice(2)] = argsArr[i + 1];
+    }
+
+    console.log(
+        Object.entries(argsObj)
+            .map(([key, val]) => `${key} is ${val}`)
+            .join(', ')
+        );
 };
 
 parseArgs();

src/cli/env.js

@@ -1,5 +1,9 @@
 const parseEnv = () => {
-    // Write your code here 
+    const variables = Object.entries(process.env)
+        .filter(([key]) => key.startsWith('RSS_'))
+        .map(([key, val]) => `${key}=${val}`)
+        .join('; ');
+    console.log(variables);
 };
 
 parseEnv();

src/fs/copy.js

@@ -1,5 +1,29 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const copy = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const filesFolder = path.join(__dirname, 'files');
+    const copyFolder = path.join(__dirname, 'files_copy');
+
+    if (fs.existsSync(filesFolder)) {
+        if (fs.existsSync(copyFolder)) {
+            throw new Error ('FS operation failed: files_copy is already exist');
+        } else {
+            fs.cp(
+                filesFolder,
+                copyFolder,
+                { recursive: true },
+                (error) => {
+                    if (error) throw error;
+                }
+            )
+        }
+    } else {
+        throw new Error ('FS operation failed: files folder does not exist');
+    }
 };
 
 await copy();

src/fs/create.js

@@ -1,5 +1,23 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const create = async () => {
-    // Write your code here 
-};
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const fileDir = path.join(__dirname, 'files', 'fresh.txt');
+
+    if (fs.existsSync(fileDir)) {
+        throw new Error ('FS operation failed: fresh.txt is already exist');
+    } else {
+        fs.writeFile(
+            fileDir,
+            'I am fresh and young',
+            (error) => {
+                if (error) throw error;
+            }
+        );
+    }
+}
 
 await create();

src/fs/delete.js

@@ -1,5 +1,22 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const remove = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const file = path.join(__dirname, 'files', 'fileToRemove.txt');
+
+    if (fs.existsSync(file)) {
+        fs.unlink(
+            file,
+            (error) => {
+                if (error) throw error;
+            }
+        );
+    } else {
+        throw new Error ('FS operation failed: fileToRemove.txt does not exist');
+    }
 };
 
 await remove();

src/fs/list.js

@@ -1,5 +1,20 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const list = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const filesFolder = path.join(__dirname, 'files');
+
+    if (fs.existsSync(filesFolder)) {
+        fs.readdir(filesFolder, (error, files) => {
+            if (error) throw error;
+            console.log(files.join('\n'));
+        });
+    } else {
+        throw new Error ('FS operation failed: files folder does not exist');
+    }
 };
 
 await list();

src/fs/read.js

@@ -1,5 +1,24 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const read = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const file = path.join(__dirname, 'files', 'fileToRead.txt');
+
+    if (fs.existsSync(file)) {
+        fs.readFile(
+            file,
+            'utf-8',
+            (error, data) => {
+                if (error) throw error;
+                console.log(data);
+            }
+        );
+    } else {
+        throw new Error ('FS operation failed: fileToRead.txt does not exist');
+    }
 };
 
 await read();

src/fs/rename.js

@@ -1,5 +1,26 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const rename = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const wrongFile = path.join(__dirname, 'files', 'wrongFilename.txt');
+    const properFile = path.join(__dirname, 'files', 'properFilename.md');
+
+    if (fs.existsSync(wrongFile)) {
+        fs.rename(
+            wrongFile,
+            properFile,
+            (error) => {
+                if (error) throw error;
+            }
+        );
+    } else if (fs.existsSync(properFile)) {
+        throw new Error ('FS operation failed: properFilename.md is already exist');
+    } else {
+        throw new Error ('FS operation failed: wrongFilename.txt does not exist');
+    }
 };
 
 await rename();

src/hash/calcHash.js

@@ -1,5 +1,18 @@
+import { createHash } from 'crypto';
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const calculateHash = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const file = path.join(__dirname, 'files', 'fileToCalculateHashFor.txt');
+
+    const readStream = fs.createReadStream(file);
+    const hash = createHash('sha256');
+
+    readStream.on('data', (chunk) => hash.update(chunk));
+    readStream.on('end', () => console.log(hash.digest('hex')));
 };
 
 await calculateHash();

src/modules/cjsToEsm.cjs → src/modules/esm.mjs

@@ -1,17 +1,19 @@
-const path = require('path');
-const { release, version } = require('os');
-const { createServer: createServerHttp } = require('http');
-require('./files/c');
+import path from 'path';
+import { fileURLToPath } from 'url';
+import { release, version } from 'os';
+import { createServer as createServerHttp } from 'http';
+import { readFile } from 'fs/promises';
+import './files/c.js';
 
-const random = Math.random();
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+
+const a = JSON.parse(await readFile(path.join(__dirname, './files/a.json'), { encoding: 'utf8' }));
+const b = JSON.parse(await readFile(path.join(__dirname, './files/b.json'), { encoding: 'utf8' }));
 
-let unknownObject;
+const random = Math.random();
 
-if (random > 0.5) {
-    unknownObject = require('./files/a.json');
-} else {
-    unknownObject = require('./files/b.json');
-}
+const unknownObject = random > 0.5 ? a : b;
 
 console.log(`Release ${release()}`);
 console.log(`Version ${version()}`);
@@ -33,8 +35,7 @@ myServer.listen(PORT, () => {
     console.log('To terminate it, use Ctrl+C combination');
 });
 
-module.exports = {
+export {
     unknownObject,
     myServer,
-};
-
+};

src/streams/read.js

@@ -1,5 +1,15 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const read = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const file = path.join(__dirname, 'files', 'fileToRead.txt');
+
+    const readStream = fs.createReadStream(file);
+
+    readStream.on('data', (chunk) => process.stdout.write(chunk + '\n'));
 };
 
 await read();

src/streams/transform.js

@@ -1,5 +1,13 @@
+import { Transform } from 'stream';
+
+const reverseStream = new Transform({
+    transform(chunk, encoding, callback) {
+        callback(null, chunk.toString().split('').reverse().join(''));
+    }
+});
+
 const transform = async () => {
-    // Write your code here 
+    process.stdin.pipe(reverseStream).pipe(process.stdout);
 };
 
 await transform();

src/streams/write.js

@@ -1,5 +1,15 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
 const write = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const file = path.join(__dirname, 'files', 'fileToWrite.txt');
+
+    const writeStream = fs.createWriteStream(file);
+
+    process.stdin.on('data', (chunk) => writeStream.write(chunk));
 };
 
 await write();

src/zip/compress.js

@@ -1,5 +1,20 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+import { createGzip } from 'zlib';
+
 const compress = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const file = path.join(__dirname, 'files', 'fileToCompress.txt');
+    const archive = path.join(__dirname, 'files', 'archive.gz');
+
+    const readStream = fs.createReadStream(file, 'utf-8');
+    const writeStream = fs.createWriteStream(archive);
+
+    const gzip = createGzip();
+
+    readStream.pipe(gzip).pipe(writeStream);
 };
 
 await compress();

src/zip/decompress.js

@@ -1,5 +1,20 @@
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+import { createUnzip } from 'zlib';
+
 const decompress = async () => {
-    // Write your code here 
-};
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = path.dirname(__filename);
+    const file = path.join(__dirname, 'files', 'fileToCompress.txt');
+    const archive = path.join(__dirname, 'files', 'archive.gz');
+
+    const readStream = fs.createReadStream(archive);
+    const writeStream = fs.createWriteStream(file);
+
+    const unzip = createUnzip();
+
+    readStream.pipe(unzip).pipe(writeStream);
+}
 
 await decompress();