Node basics

src/cli/args.js

@@ -1,5 +1,10 @@
 const parseArgs = () => {
-  // Write your code here
+  const args = Object.values(process.argv).slice(2);
+  const strArgs = args
+    .map((arg, index) => index % 2 === 0 ? `${arg} is ${args[index + 1]}`: null)
+    .filter(Boolean)
+    .join(', ')
+  console.log(strArgs)
 };
 
 parseArgs();

src/cli/env.js

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

src/fs/copy.js

@@ -1,5 +1,18 @@
+import { copyFile, mkdir, readdir } from 'node:fs/promises';
+import { join } from 'node:path';
+
 const copy = async () => {
-  // Write your code here
+  try {
+    const originalFolderPath = await join(import.meta.dirname, './files');
+    const copyFolderPath = await join(import.meta.dirname, './files_copy');
+    await mkdir(copyFolderPath);
+    const files = await readdir(originalFolderPath);
+    for ( const file of files ) {
+      copyFile(join(originalFolderPath, file), join(copyFolderPath, file));
+    }
+  } catch {
+    throw new Error('FS operation failed');
+  } 
 };
 
 await copy();

src/fs/create.js

@@ -1,5 +1,13 @@
-const create = async () => {
-  // Write your code here
-};
+  import * as fs from 'node:fs/promises';
+  import{ join } from 'node:path';
 
-await create();
+  const create = async () => {
+    try {
+      const filePath = await join(import.meta.dirname, './files/fresh.txt');
+      await fs.writeFile(filePath, 'I am fresh and young');
+    } catch {
+      throw new Error('FS operation failed');
+    }
+  };
+
+  await create();

src/fs/delete.js

@@ -1,5 +1,13 @@
+import { rm } from 'node:fs/promises';
+import { join } from 'node:path'
+
 const remove = async () => {
-  // Write your code here
+  try {
+    const path = await join(import.meta.dirname, './files/fileToRemove.txt');
+    await rm(path);
+  } catch {
+      throw new Error('FS operation failed');
+  }
 };
 
 await remove();

src/fs/list.js

@@ -1,5 +1,14 @@
+import { readdir } from 'node:fs/promises';
+import { join } from 'node:path'
+
 const list = async () => {
-  // Write your code here
+  try {
+    const files = await readdir(join(import.meta.dirname, './files'));
+    console.log(files);
+  } catch {
+    throw new Error('FS operation failed');
+  }
+
 };
 
 await list();

src/fs/read.js

@@ -1,5 +1,10 @@
+import { join } from 'node:path'
+import { readFile } from 'node:fs/promises';
+
 const read = async () => {
-  // Write your code here
+  const path = await join(import.meta.dirname, './files/fileToRead.txt');
+  const fileContent = await readFile(path, { encoding: 'utf-8' });
+  console.log(fileContent);
 };
 
 await read();

src/fs/rename.js

@@ -1,5 +1,16 @@
+import * as fs from 'node:fs/promises';
+import { join } from 'node:path';
+
 const rename = async () => {
-  // Write your code here
+  try {
+      const path = import.meta.dirname
+      const oldNamePath = await join(import.meta.dirname, './files/wrongFilename.txt');
+      const newNamePath = await join(import.meta.dirname, './files/properFilename.md');
+      await fs.rename(oldNamePath, newNamePath);
+  } catch {
+    throw new Error('FS operation failed');
+  } 
+
 };
 
 await rename();

src/hash/calcHash.js

@@ -1,5 +1,14 @@
+import { createHash } from 'node:crypto';
+import { createReadStream } from 'node:fs';
+import { join } from 'node:path';
+
 const calculateHash = async () => {
-  // Write your code here
+  const hash = createHash('sha256');
+  const read = createReadStream(join(import.meta.dirname, './files/fileToCalculateHashFor.txt'), { encoding: 'utf-8' });
+  read.on('data', (chunk) => hash.update(chunk));
+  read.on('end', () => {
+    console.log(hash.digest('hex'))
+  });
 };
 
 await calculateHash();

src/modules/esm.mjs

@@ -0,0 +1,32 @@
+import * as path from 'node:path';
+import { release, version } from 'node:os';
+import { createServer as createServerHttp } from 'node:http';
+
+import './files/c.cjs';
+
+
+const random = Math.random();
+
+const { default: unknownObject} = random > 0.5 ? await import('./files/a.json', { with: {type: 'json' } }) : await  import('./files/b.json', { with: { type: 'json' } });
+
+console.log(`Release ${release()}`);
+console.log(`Version ${version()}`);
+console.log(`Path segment separator is "${path.sep}"`);
+
+console.log(`Path to current file is ${import.meta.filename}`);
+console.log(`Path to current directory is ${import.meta.dirname}`);
+
+const myServer = createServerHttp((_, res) => {
+  res.end('Request accepted');
+});
+
+const PORT = 3000;
+
+console.log(unknownObject);
+
+myServer.listen(PORT, () => {
+  console.log(`Server is listening on port ${PORT}`);
+  console.log('To terminate it, use Ctrl+C combination');
+});
+
+export { myServer, unknownObject }

src/streams/files/fileToWrite.txt

@@ -0,0 +1 @@
+

src/streams/read.js

@@ -1,5 +1,11 @@
+import { createReadStream } from 'fs';
+import { stdout } from 'process';
+
 const read = async () => {
-  // Write your code here
+  const read = createReadStream('./src/streams/files/fileToRead.txt', { encoding: 'utf-8' });
+  read.on('data', (chunk) => {
+    stdout.write(chunk);
+  }) 
 };
 
 await read();

src/streams/transform.js

@@ -1,5 +1,12 @@
+import { Transform } from 'stream';
 const transform = async () => {
-  // Write your code here
+  const reverseData = new Transform({
+    transform(chunk, encoding, callback) {
+      const reversedChunk = chunk.toString().split('').reverse().join('');
+      callback(null, reversedChunk);
+    }
+  })
+  process.stdin.pipe(reverseData).pipe(process.stdout);
 };
 
 await transform();

src/streams/write.js

@@ -1,5 +1,10 @@
+import { createWriteStream } from 'fs';
+import { stdin } from 'process';
+import { join } from 'path';
+
 const write = async () => {
-  // Write your code here
+  const output = createWriteStream(join(import.meta.dirname, './files/fileToWrite.txt'));
+  stdin.pipe(output);
 };
 
 await write();

src/wt/main.js

@@ -2,4 +2,4 @@ const performCalculations = async () => {
   // Write your code here
 };
 
-await performCalculations();
+await performCalculations();

src/zip/compress.js

@@ -1,5 +1,15 @@
+import {
+  createReadStream,
+  createWriteStream,
+} from 'node:fs';
+import  { createGzip } from 'node:zlib';
+import { join } from 'path';
+
 const compress = async () => {
-  // Write your code here
+  const gzip = createGzip();
+  const source = createReadStream(join(import.meta.dirname, './files/fileToCompress.txt'));
+  const destination = createWriteStream(join(import.meta.dirname, './files/archive.gz'));
+  source.pipe(gzip).pipe(destination);
 };
 
 await compress();

src/zip/decompress.js

@@ -1,5 +1,15 @@
+import {
+  createReadStream,
+  createWriteStream,
+} from 'node:fs';
+import  { createGunzip } from 'node:zlib';
+import { join } from 'path';
+
 const decompress = async () => {
-  // Write your code here
+    const gunzip = createGunzip();
+    const destination = createWriteStream(join(import.meta.dirname, './files/fileToCompress.txt'));
+    const source = createReadStream(join(import.meta.dirname, './files/archive.gz'));
+    source.pipe(gunzip).pipe(destination);
 };
 
 await decompress();