Nodejs basics task 1

src/cli/args.js

@@ -1,5 +1,9 @@
 const parseArgs = () => {
-    // Write your code here 
+    process.argv.slice(2).forEach((arg, i, arr) => {
+        if (arg.startsWith('--')) {
+            console.log(`${arg.replace('--', '')} is ${arr[i + 1]}`);
+        }
+    });
 };
 
 parseArgs();

src/cli/env.js

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

src/cp/cp.js

@@ -1,6 +1,15 @@
+import {fork} from 'child_process';
+import {fileURLToPath} from "url";
+import path from "path";
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const scriptPath = `${dirname}/files/script.js`;
 const spawnChildProcess = async (args) => {
-    // Write your code here
+    const childProcess = fork(scriptPath, args, {silent: true});
+    process.stdin.pipe(childProcess.stdin);
+    childProcess.stdout.pipe(process.stdout);
 };
 
 // Put your arguments in function call to test this functionality
-spawnChildProcess( /* [someArgument1, someArgument2, ...] */);
+spawnChildProcess(  ['someArgument1', 'someArgument2'] );

src/fs/copy.js

@@ -1,5 +1,21 @@
+import fs from 'fs';
+import path from 'path';
+import {fileURLToPath} from 'url';
+
+const currentFilename = fileURLToPath(import.meta.url);
+const currentDirectory = path.dirname(currentFilename);
+const filesDirectory = path.join(currentDirectory, '/files');
+const copyFilesDirectory = path.join(currentDirectory, '/files_copy');
+const errorMsg = 'FS operation failed';
 const copy = async () => {
-    // Write your code here 
+    if (!fs.existsSync(filesDirectory) || fs.existsSync(copyFilesDirectory)) throw new Error(errorMsg);
+
+    const filenames = fs.readdirSync(filesDirectory);
+    fs.mkdirSync(copyFilesDirectory);
+
+    for (let filename of filenames) {
+        fs.copyFile(path.join(filesDirectory, `/${filename}`), path.join(copyFilesDirectory, `/${filename}`), (e)=>{})
+    }
 };
 
 await copy();

src/fs/create.js

@@ -1,5 +1,16 @@
+import fs from 'fs/promises';
+import path from 'path';
+import {fileURLToPath} from 'url';
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const filePath = `${dirname}/files/fresh.txt`;
 const create = async () => {
-    // Write your code here 
+    try {
+        await fs.writeFile(filePath, 'I am fresh and young', {flag: 'wx'});
+    } catch (e) {
+        throw new Error('FS operation failed');
+    }
 };
 
 await create();

src/fs/delete.js

@@ -1,5 +1,17 @@
+import fs from 'fs/promises';
+import {fileURLToPath} from 'url';
+import path from 'path';
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const fileToRemove = path.join(dirname, '/files/fileToRemove.txt');
+const errorMsg = 'FS operation failed';
 const remove = async () => {
-    // Write your code here 
+    try {
+        await fs.rm(fileToRemove)
+    } catch (e) {
+        throw new Error(errorMsg);
+    }
 };
 
 await remove();

src/fs/list.js

@@ -1,5 +1,18 @@
+import fs from 'fs/promises';
+import path from 'path';
+import {fileURLToPath} from 'url';
+
+const currentFilename = fileURLToPath(import.meta.url);
+const filesDirectory = path.join(path.dirname(currentFilename), '/files')
 const list = async () => {
-    // Write your code here 
+    try {
+        const files = await fs.readdir(filesDirectory);
+        for (const file of files) {
+            console.log(file);
+        }
+    } catch (err) {
+        throw new Error('FS operation failed')
+    }
 };
 
 await list();

src/fs/read.js

@@ -1,5 +1,16 @@
+import fs from 'fs/promises';
+import path from 'path';
+import {fileURLToPath} from 'url';
+
+const currentFilename = fileURLToPath(import.meta.url);
+const fileToRead = path.join(path.dirname(currentFilename), '/files/fileToRea3d.txt');
 const read = async () => {
-    // Write your code here 
+    try {
+        const content = await fs.readFile(fileToRead, {encoding: 'utf8'});
+        console.log(content);
+    } catch (e) {
+        throw new Error('FS operation failed');
+    }
 };
 
 await read();

src/fs/rename.js

@@ -1,5 +1,23 @@
+import fs from 'fs/promises';
+import {fileURLToPath} from "url";
+import path from "path";
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const oldFilePath = path.join(dirname, '/files/wrongFilename.txt');
+const newFilePath = path.join(dirname, '/files/properFilename.md');
+const errorMsg = 'FS operation failed';
+
 const rename = async () => {
-    // Write your code here 
+    const fileExists = await fs.access(newFilePath, fs.constants.F_OK).then(() => true, () => false);
+    if (fileExists) throw new Error(errorMsg);
+
+    try {
+        await fs.rename(oldFilePath, newFilePath);
+    } catch (e) {
+        console.log(e);
+        throw new Error(errorMsg);
+    }
 };
 
 await rename();

src/hash/calcHash.js

@@ -1,5 +1,23 @@
+import crypto from 'crypto';
+import fs from 'fs';
+import {fileURLToPath} from "url";
+import path from "path";
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const hashFilePath = `${dirname}/files/fileToCalculateHashFor.txt`;
+
 const calculateHash = async () => {
-    // Write your code here 
+    const fd = fs.createReadStream(hashFilePath);
+    const hash = crypto.createHash('sha256');
+    hash.setEncoding('hex');
+
+    fd.on('end', function () {
+        hash.end();
+        console.log(hash.read());
+    });
+
+    fd.pipe(hash);
 };
 
 await calculateHash();

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

@@ -1,18 +1,22 @@
-const path = require('path');
-const { release, version } = require('os');
-const { createServer: createServerHttp } = require('http');
-require('./files/c');
+import path from 'path';
+import {release, version} from 'os';
+import {createServer as createServerHttp} from 'http';
+import './files/c.js';
+import {fileURLToPath} from "url";
 
 const random = Math.random();
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
 
 let unknownObject;
 
 if (random > 0.5) {
-    unknownObject = require('./files/a.json');
+    ({default: unknownObject} = await import("./files/a.json", {assert: {type: "json"}}))
 } else {
-    unknownObject = require('./files/b.json');
+    ({default: unknownObject} = await import("./files/b.json", {assert: {type: "json"}}))
 }
 
+
 console.log(`Release ${release()}`);
 console.log(`Version ${version()}`);
 console.log(`Path segment separator is "${path.sep}"`);
@@ -33,7 +37,7 @@ myServer.listen(PORT, () => {
     console.log('To terminate it, use Ctrl+C combination');
 });
 
-module.exports = {
+export {
     unknownObject,
     myServer,
 };

src/streams/files/fileToWrite.txt

@@ -0,0 +1,2 @@
+test write
+test yhdfbd 

src/streams/read.js

@@ -1,5 +1,12 @@
+import fs from 'fs';
+import path from 'path';
+import {fileURLToPath} from 'url';
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const filePath = `${dirname}/files/fileToRead.txt`;
 const read = async () => {
-    // Write your code here 
+    fs.createReadStream(filePath).pipe(process.stdout);
 };
 
 await read();

src/streams/transform.js

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

src/streams/write.js

@@ -1,5 +1,13 @@
+import fs from 'fs';
+import path from 'path';
+import {fileURLToPath} from 'url';
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const filePath = `${dirname}/files/fileToWrite.txt`;
 const write = async () => {
-    // Write your code here 
+   const file = fs.createWriteStream(filePath, {flags: 'a'});
+    process.stdin.pipe(file);
 };
 
 await write();

src/wt/main.js

@@ -1,5 +1,24 @@
+import {cpus} from 'os';
+import {fileURLToPath} from "url";
+import path from "path";
+import {Worker} from 'worker_threads';
+
+
+const filename = fileURLToPath(import.meta.url);
+const workerPath = `${path.dirname(filename)}/worker.js`;
 const performCalculations = async () => {
-    // Write your code here
-};
+    const cpuNumber = cpus().length;
+    const workersArray = [];
+    for (let i = 0; i < cpuNumber; i++) {
+        const promise = new Promise((resolve) => {
+            const worker = new Worker(workerPath, {workerData: i + 10});
+            worker.on('message', (res) => resolve({status: 'resolved', data: res}));
+            worker.on('error', () => resolve({status: 'error', data: null}));
+        });
+        workersArray.push(promise);
+    }
+    const resul = await Promise.all(workersArray);
+    console.log(resul);
+}
 
 await performCalculations();

src/wt/worker.js

@@ -1,8 +1,9 @@
+import {workerData, parentPort} from 'worker_threads';
 // n should be received from main thread
 const nthFibonacci = (n) => n < 2 ? n : nthFibonacci(n - 1) + nthFibonacci(n - 2);
 
 const sendResult = () => {
-    // This function sends result of nthFibonacci computations to main thread
+    parentPort.postMessage(nthFibonacci(workerData));
 };
 
 sendResult();

src/zip/compress.js

@@ -1,5 +1,19 @@
+import {createGzip} from 'zlib';
+import {pipeline} from 'stream/promises';
+import {createReadStream, createWriteStream} from 'fs';
+import {fileURLToPath} from "url";
+import path from "path";
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const compressFile = `${dirname}/files/fileToCompress.txt`;
+const compressedFile = `${dirname}/files/archive.gz`;
+
 const compress = async () => {
-    // Write your code here 
+    const gzip = createGzip();
+    const source = createReadStream(compressFile);
+    const destination = createWriteStream(compressedFile);
+    await pipeline(source, gzip, destination);
 };
 
 await compress();

src/zip/decompress.js

@@ -1,5 +1,19 @@
+import {createGunzip} from 'zlib';
+import {pipeline} from 'stream/promises';
+import {createReadStream, createWriteStream} from 'fs';
+import {fileURLToPath} from "url";
+import path from "path";
+
+const filename = fileURLToPath(import.meta.url);
+const dirname = path.dirname(filename);
+const decompressedFile = `${dirname}/files/fileToDecompress.txt`;
+const compressedFile = `${dirname}/files/archive.gz`;
+
 const decompress = async () => {
-    // Write your code here 
+    const gzip = createGunzip();
+    const source = createReadStream(compressedFile);
+    const destination = createWriteStream(decompressedFile);
+    await pipeline(source, gzip, destination);
 };
 
 await decompress();