Node.js basics

src/cli/args.js

@@ -1,5 +1,12 @@
 const parseArgs = () => {
-    // Write your code here 
+    const argv = process.argv.slice(2);
+
+    const outputArray = [];
+    for (let i = 0; i < argv.length; i += 2) {
+        outputArray.push(`${argv[i].slice(2)} is ${argv[i + 1]}`);
+    }
+
+    console.log(outputArray.join(', '));
 };
 
 parseArgs();

src/cli/env.js

@@ -1,5 +1,12 @@
 const parseEnv = () => {
-    // Write your code here 
+    const outputArray = [];
+    for (let envKey in process.env) {
+        if (envKey.startsWith('RSS_')) {
+            outputArray.push(`${envKey}=${process.env[envKey]}`);
+        }
+    }
+
+    console.log(outputArray.join('; '));
 };
 
 parseEnv();

src/fs/copy.js

@@ -1,5 +1,23 @@
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+import { existsSync } from 'fs';
+import { cp } from "fs/promises";
+
 const copy = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = dirname(__filename);
+    const isFilesFolderExist = existsSync(`${__dirname}/files`);
+    const isFilesCopyFolderExist = existsSync(`${__dirname}/files_copy`);
+
+    if (!isFilesFolderExist || isFilesCopyFolderExist) {
+        throw new Error('FS operation failed');
+    }
+
+    try {
+        await cp(`${__dirname}/files`, `${__dirname}/files_copy`, { recursive: true })
+    } catch (error) {
+        console.log(error);
+    }
 };
 
 await copy();

src/fs/create.js

@@ -1,5 +1,23 @@
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+import { existsSync } from 'fs';
+import { writeFile } from "fs/promises";
+
 const create = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = dirname(__filename);
+    const isFileExist = existsSync(`${__dirname}/files/fresh.txt`);
+
+    try {
+      if (!isFileExist) {
+        const data = 'I am fresh and young';
+        await writeFile(`${__dirname}/files/fresh.txt`, data, { encoding: 'utf8' });
+      } else {
+        throw new Error('FS operation failed');
+      }
+    } catch(error) {
+      throw new Error('FS operation failed');
+    }
 };
 
-await create();
+await create();

src/fs/delete.js

@@ -1,5 +1,16 @@
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+import { rm } from "fs/promises";
+
 const remove = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = dirname(__filename);
+
+    try {
+        await rm(`${__dirname}/files/fileToRemove.txt`);
+    } catch (error) {
+        throw new Error('FS operation failed');
+    }
 };
 
 await remove();

src/fs/list.js

@@ -1,5 +1,18 @@
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+import { readdir } from "fs/promises";
+
 const list = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = dirname(__filename);
+
+    try {
+        const dirents = await readdir(`${__dirname}/files`, { withFileTypes: true });
+        const files = dirents.filter(d => d.isFile()).map(d => d.name);
+        console.log(files);
+    } catch(error) {
+        throw new Error('FS operation failed');
+    }
 };
 
 await list();

src/fs/read.js

@@ -1,5 +1,17 @@
+import { readFile } from 'fs/promises';
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+
 const read = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = dirname(__filename);
+
+    try {
+        const contents = await readFile(`${__dirname}/files/fileToRead.txt`, { encoding: 'utf8' });
+        console.log(contents);
+    } catch (error) {
+        throw new Error('FS operation failed')
+    }
 };
 
 await read();

src/fs/rename.js

@@ -1,5 +1,17 @@
+import { rename as renameFile } from "fs/promises";
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+
 const rename = async () => {
-    // Write your code here 
+    const __filename = fileURLToPath(import.meta.url);
+    const __dirname = dirname(__filename);
+
+    try {
+        await renameFile(`${__dirname}/files/wrongFilename.txt`, `${__dirname}/files/properFilename.md`);
+    } catch (error) {
+        console.log("error", error);
+        throw new Error("FS operation failed");
+    }
 };
 
-await rename();
+await rename();

src/hash/calcHash.js

@@ -1,5 +1,25 @@
+import { readFile } from 'fs/promises';
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+import { createHash } from 'crypto';
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = dirname(__filename);
+const content = await readFile(`${__dirname}/files/fileToCalculateHashFor.txt`, { encoding: 'utf8' });
+console.log('content', content);
+
 const calculateHash = async () => {
-    // Write your code here 
+    const hash = createHash('sha256');
+
+    hash.on('readable', () => {
+      const data = hash.read();
+      if (data) {
+        console.log(data.toString('hex'));
+      }
+    });
+
+    hash.write(content);
+    hash.end();
 };
 
 await calculateHash();