task1 - Node.js basics

src/cli/args.js

@@ -1,5 +1,12 @@
 const parseArgs = () => {
-    // Write your code here 
+    const arg = process.argv.slice(2)
+    let result = ''
+    arg.forEach((item, i) => {
+        if(i % 2 === 0){
+            result = result + `${item.slice(2)} is ${arg[i + 1]}, `
+        }
+    })
+    console.log(result)
 };
 
 parseArgs();

src/cli/env.js

@@ -1,5 +1,15 @@
 const parseEnv = () => {
-    // Write your code here 
+const env = process.env;
+const result = {};
+
+for (const key in env) {
+  if (key.startsWith('RSS_')) {
+    result[key] = env[key];
+  }
+}
+
+const output = Object.entries(result).map(([key, value]) => `${key}=${value}`).join('; ');
+  console.log(output);
 };
 
 parseEnv();

src/fs/copy.js

@@ -1,5 +1,19 @@
+import fs from 'node:fs/promises'
+import path from 'node:path'
+import { fileURLToPath } from 'node:url';
+const filename = fileURLToPath(import.meta.url)
+const dirname = path.dirname(filename)
+const tagetSourceDirName = path.join(dirname, 'files');
+const tagetDistDirName = path.join(dirname, 'files_copy');
+
 const copy = async () => {
-    // Write your code here 
+    try {
+        await fs.access(tagetSourceDirName)
+        await fs.cp(tagetSourceDirName, tagetDistDirName, {recursive: true  , errorOnExist: true, force: false})
+
+    } catch (error) {
+        throw new Error('FS operation failed')
+    }
 };
 
 await copy();

src/fs/create.js

@@ -1,5 +1,23 @@
+import fs from 'node:fs/promises'
+import path from 'node:path'
+import { fileURLToPath } from 'node:url';
+const filename = fileURLToPath(import.meta.url)
+const dirname = path.dirname(filename)
+const freshFile = path.join(dirname, 'files','fresh.txt');
+
+
+
 const create = async () => {
-    // Write your code here 
+    try {
+        await fs.access(freshFile)
+        throw new Error('FS operation failed');
+    } catch (error) {
+        if (error.code === 'ENOENT') {
+            await fs.writeFile(freshFile , 'I am fresh and young');
+          } else {
+            console.error(error.message);
+          }
+    }
 };
 
 await create();

src/fs/delete.js

@@ -1,5 +1,16 @@
+import fs from 'node:fs/promises'
+import path from 'node:path'
+import { fileURLToPath } from 'node:url';
+const filename = fileURLToPath(import.meta.url)
+const dirname = path.dirname(filename)
+const targetFile = path.join(dirname, 'files','fileToRemove.txt');
+
 const remove = async () => {
-    // Write your code here 
+   try  {
+    await fs.unlink(targetFile)
+   } catch(error){
+    throw new Error('FS operation failed')
+   }
 };
 
 await remove();

src/fs/list.js

@@ -1,5 +1,19 @@
+import {readdir} from 'node:fs/promises'
+import {dirname, join} from 'node:path'
+import { fileURLToPath } from 'node:url';
+const fileName = fileURLToPath(import.meta.url)
+const dirName = dirname(fileName)
+const tagetDirName = join(dirName, 'files')
+
+
+
 const list = async () => {
-    // Write your code here 
+    try {
+        const files = await readdir(tagetDirName)
+        console.log("files",files)
+    } catch (error) {
+        throw new Error('FS operation failed')
+    }
 };
 
 await list();

src/fs/read.js

@@ -1,5 +1,17 @@
+import {readFile} from 'node:fs/promises'
+import {dirname, join} from 'node:path'
+import { fileURLToPath } from 'node:url';
+const fileName = fileURLToPath(import.meta.url)
+const dirName = dirname(fileName)
+const tagetFileName = join(dirName, 'files', 'fileToRead.txt')
+
 const read = async () => {
-    // Write your code here 
+    try {
+        const content = await readFile(tagetFileName, 'utf-8')
+        console.log(content)
+    } catch (error) {
+        throw new Error('FS operation failed')
+    }
 };
 
 await read();

src/fs/rename.js

@@ -1,5 +1,27 @@
+import fs from 'node:fs/promises'
+import path from 'node:path'
+import { fileURLToPath } from 'node:url';
+const filename = fileURLToPath(import.meta.url)
+const dirname = path.dirname(filename)
+const oldFileName = path.join(dirname, 'files', 'wrongFilename.txt')
+const newFileName = path.join(dirname, 'files', 'properFilename.md')
 const rename = async () => {
-    // Write your code here 
+    try {
+        await fs.access(newFileName)
+        throw new Error('FS operation failed')
+    } catch (error) {
+        if(error.code === 'ENOENT'){
+            try {
+                await fs.access(oldFileName)
+                await fs.rename(oldFileName, newFileName) 
+            } catch (error) {
+                throw new Error('FS operation failed')
+            }
+
+        }  else{
+            console.error(error.message);
+        }
+    }
 };
 
 await rename();

src/hash/calcHash.js

@@ -1,5 +1,12 @@
+import crypto from 'crypto'
+import fs from 'fs'
+
 const calculateHash = async () => {
-    // Write your code here 
+    const hash = crypto.createHash('sha256');
+    const stream = fs.createReadStream(new URL('./files/fileToCalculateHashFor.txt', import.meta.url));
+
+    stream.on('data', (chunk) => hash.update(chunk));
+    stream.on('end', () => console.log(hash.digest('hex')));
 };
 
 await calculateHash();

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

@@ -1,17 +1,21 @@
-const path = require('path');
-const { release, version } = require('os');
-const { createServer: createServerHttp } = require('http');
-require('./files/c.cjs');
+import path from 'path';
+import { release, version } from 'os';
+import { createServer as createServerHttp } from 'http';
+import { fileURLToPath } from 'url';
+import { readFileSync } from 'fs';
+import './files/c.cjs'; 
 
 const random = Math.random();
 
 let unknownObject;
 
 if (random > 0.5) {
-    unknownObject = require('./files/a.json');
+    unknownObject = JSON.parse(readFileSync(new URL('./files/a.json', import.meta.url)));
 } else {
-    unknownObject = require('./files/b.json');
+    unknownObject = JSON.parse(readFileSync(new URL('./files/b.json', import.meta.url)));
 }
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
 
 console.log(`Release ${release()}`);
 console.log(`Version ${version()}`);
@@ -33,8 +37,7 @@ myServer.listen(PORT, () => {
     console.log('To terminate it, use Ctrl+C combination');
 });
 
-module.exports = {
+export {
     unknownObject,
     myServer,
-};
-
+};

src/streams/read.js

@@ -1,5 +1,11 @@
+import { createReadStream } from 'node:fs';
+
 const read = async () => {
-    // Write your code here 
+    const readStream = createReadStream(new URL('./files/fileToRead.txt', import.meta.url), 'utf8');
+    readStream.pipe(process.stdout)
+    readStream.on('end', () => {
+      console.log('\n');
+    });
 };
 
 await read();

src/streams/transform.js

@@ -1,5 +1,22 @@
+import { pipeline, Transform } from 'stream';
+
 const transform = async () => {
-    // Write your code here 
+
+    const transform = new Transform({
+        transform(chunk, _, cb) {
+          const result = chunk.toString().split('').reverse().join('');
+          cb(null, result + '\n');
+        }
+      });
+
+      console.log('Введите текст (для выхода Ctrl+С)');
+
+       pipeline(
+        process.stdin,
+        transform,
+        process.stdout,
+        (err)=>{}
+      );
 };
 
 await transform();

src/streams/write.js

@@ -1,5 +1,16 @@
+import { createWriteStream } from 'node:fs';
+import { pipeline } from 'stream';
 const write = async () => {
-    // Write your code here 
+    const writableStream = createWriteStream(new URL('./files/fileToWrite.txt', import.meta.url), 'utf8');
+
+    console.log('Введите текст (для выхода Ctrl+С)');
+
+         pipeline(
+            process.stdin,
+            writableStream,
+            (err)=>{}
+        );
+
 };
 
 await write();

src/zip/compress.js

@@ -1,5 +1,10 @@
+import fs from 'fs'
+import zlib from 'zlib'
 const compress = async () => {
-    // Write your code here 
+    const readableStream = fs.createReadStream(new URL('./files/fileToCompress.txt', import.meta.url))
+    const writeableStream = fs.createWriteStream(new URL('./files/archive.gz', import.meta.url))
+    const gzip = zlib.createGzip()
+    readableStream.pipe(gzip).pipe(writeableStream)
 };
 
 await compress();

src/zip/decompress.js

@@ -1,5 +1,10 @@
+import fs from 'fs';
+import zlib from 'zlib';
 const decompress = async () => {
-    // Write your code here 
+    const readableStream = fs.createReadStream( new URL('./files/archive.gz', import.meta.url));
+    const writeableStream = fs.createWriteStream(new URL('./files/fileToCompress.txt', import.meta.url));
+    const gunzip = zlib.createGunzip();
+    readableStream.pipe(gunzip).pipe(writeableStream);
 };
 
 await decompress();