Nodejs basics

Readme.md

@@ -1 +1,35 @@
-# Node.js basics
+# Node.js basics
+
+# For run each single task you should input follow lines into terminal:
+
+File system (src/fs):
+create.js: npm run fs:create
+copy.js: npm run fs:copy
+rename.js: npm run fs:rename
+delete.js: npm run fs:delete
+list.js: npm run fs:list
+read.js: nmp run fs:read
+
+Command line interface(src/cli):
+env.js: $env:RSS_name-variable="value"; npm run cli:env
+args.js: npm run cli:args -- --propName value --prop2Name value2
+
+Modules(src/modules):
+cjsToEsm.mjs: npm run modules
+
+Hash (src/hash):
+calcHash.js: npm run hash
+
+Streams (src/streams):
+read.js: npm run streams:read
+write.js: npm run streams:write
+transform: npm run streams:transform
+
+Zlib (src/zip):
+compress.js: npm run zip:compress
+decompress.js: npm run zip:decompress
+
+Worker Threads (src/wt):
+main.js: npm run wt
+ATTENTION: in worker.js file was added special condition for throw error!!!!!!!! JUST FOR AN EXAMPLE
+

package.json

@@ -4,7 +4,24 @@
   "description": "This repository is the part of nodejs-assignments https://github.com/AlreadyBored/nodejs-assignments",
   "type": "module",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "fs:create": "node src/fs/create.js",
+    "fs:copy": "node src/fs/copy.js",
+    "fs:rename": "node src/fs/rename.js",
+    "fs:delete": "node src/fs/delete.js",
+    "fs:list": "node src/fs/list.js",
+    "fs:read": "node src/fs/read.js",
+    "cli:env": "node src/cli/env.js",
+    "cli:args": "node src/cli/args.js",
+    "modules": "node src/modules/cjsToEsm.mjs",
+    "hash": "node src/hash/calcHash.js",
+    "streams:read": "node src/streams/read.js",
+    "streams:write": "node src/streams/write.js",
+    "streams:transform": "node src/streams/transform.js",
+    "zip:compress": "node src/zip/compress.js",
+    "zip:decompress": "node src/zip/decompress.js",
+    "wt": "node src/wt/main.js",
+    "cp": "node src/cp/cp.js"
   },
   "repository": {
     "type": "git",

src/cli/args.js

@@ -1,3 +1,32 @@
 export const parseArgs = () => {
-    // Write your code here 
-};
+  const args = process.argv;
+  const flags = {
+    prefix: "--",
+    propName: "propName",
+    prop2Name: "prop2Name",
+
+    getPropWithPrefix(name) {
+      const key = name.split(this.prefix)[1];
+      return this.prefix + this[key];
+    },
+
+    getOnlyProp(value) {
+      const key = value.split(this.prefix)[1];
+      return this[key];
+    },
+  };
+
+  const output = args
+    .reduce((acc, curr, index, arr) => {
+      if (curr === flags.getPropWithPrefix(curr)) {
+        const buffer = `${flags.getOnlyProp(curr)} is ${arr[index + 1]}`;
+        acc.push(buffer);
+      }
+      return acc;
+    }, [])
+    .join(", ");
+
+  console.log(output);
+};
+
+parseArgs();

src/cli/env.js

@@ -1,3 +1,17 @@
 export const parseEnv = () => {
-    // Write your code here 
-};
+  const envArr = Object.entries(process.env);
+
+  const rssOnly = envArr.filter((value) => {
+    return value[0].startsWith("RSS_");
+  });
+
+  const output = rssOnly
+    .map((value) => {
+      return `${value[0]}=${value[1]}`;
+    })
+    .join("; ");
+
+  console.log(output);
+};
+
+parseEnv();

src/cp/cp.js

@@ -1,3 +1,9 @@
+import { fork } from "child_process";
+import { __dirname } from "../globalPath.js";
+
 export const spawnChildProcess = async (args) => {
-    // Write your code here
-};
+  fork(`${__dirname(import.meta.url)}/files/script.js`, args);
+};
+
+const envArguments = process.argv;
+spawnChildProcess(envArguments);

src/cp/files/script.js

@@ -1,12 +1,12 @@
-const arguments = process.argv.slice(2);
+const args = process.argv.slice(2);
 
-console.log(`Total number of arguments is ${arguments.length}`);
-console.log(`Arguments: ${JSON.stringify(arguments)}`);
+console.log(`Total number of arguments is ${args.length}`);
+console.log(`Arguments: ${JSON.stringify(args)}`);
 
 const echoInput = (chunk) => {
-    const chunkStringified = chunk.toString();
-    if (chunkStringified.includes('CLOSE')) process.exit(0);
-    process.stdout.write(`Received from master process: ${chunk.toString()}\n`)
+  const chunkStringified = chunk.toString();
+  if (chunkStringified.includes("CLOSE")) process.exit(0);
+  process.stdout.write(`Received from master process: ${chunk.toString()}\n`);
 };
 
-process.stdin.on('data', echoInput);
+process.stdin.on("data", echoInput);

src/fs/copy.js

@@ -1,3 +1,23 @@
+import { readdir, copyFile, mkdir } from "fs";
+import { __dirname } from "../globalPath.js";
+
 export const copy = async () => {
-    // Write your code here 
-};
+  const sourcePath = `${__dirname(import.meta.url)}/files`;
+  const copy = `${__dirname(import.meta.url)}/files_copy`;
+
+  readdir(sourcePath, (err, files) => {
+    if (err) {
+      throw new Error("FS operation failed");
+    }
+    mkdir(copy, (err) => {
+      if (err) {
+        throw new Error("FS operation failed");
+      }
+    });
+    files.forEach((file) => {
+      copyFile(`${sourcePath}/${file}`, `${copy}/${file}`, () => {});
+    });
+  });
+};
+
+copy();

src/fs/create.js

@@ -1,3 +1,18 @@
+import { stat, writeFile } from "fs";
+import { __dirname } from "../globalPath.js";
+
 export const create = async () => {
-    // Write your code here 
-};
+  const newFileName = "fresh.txt";
+  const fullPath = `${__dirname(import.meta.url)}/files/${newFileName}`;
+  const fileContent = "I am fresh and young";
+
+  stat(fullPath, (err, stats) => {
+    if (!stats) {
+      writeFile(fullPath, fileContent, () => {});
+    } else {
+      throw Error("FS operation failed");
+    }
+  });
+};
+
+create();

src/fs/delete.js

@@ -1,3 +1,14 @@
+import { unlink } from "fs";
+import { __dirname } from "../globalPath.js";
+
 export const remove = async () => {
-    // Write your code here 
-};
+  const targetPath = `${__dirname(import.meta.url)}/files/fileToRemove.txt`;
+
+  unlink(targetPath, (err) => {
+    if (err) {
+      throw new Error("FS operation failed");
+    }
+  });
+};
+
+remove();

src/fs/list.js

@@ -1,3 +1,15 @@
+import { readdir } from "fs";
+import { __dirname } from "../globalPath.js";
+
 export const list = async () => {
-    // Write your code here 
-};
+  const sourcePath = `${__dirname(import.meta.url)}/files`;
+
+  readdir(sourcePath, (err, files) => {
+    if (err) {
+      throw new Error("FS operation failed");
+    }
+    files.forEach((file) => console.log(file));
+  });
+};
+
+list();

src/fs/read.js

@@ -1,3 +1,15 @@
+import { readFile } from "fs";
+import { __dirname } from "../globalPath.js";
+
 export const read = async () => {
-    // Write your code here 
-};
+  const path = `${__dirname(import.meta.url)}/files/fileToRead.txt`;
+
+  readFile(path, "utf8", (err, data) => {
+    if (err) {
+      throw new Error("FS operation failed");
+    }
+    console.log(data);
+  });
+};
+
+read();

src/fs/rename.js

@@ -1,3 +1,20 @@
-export const rename = async () => {
-    // Write your code here 
-};
+import { rename } from "fs";
+import { __dirname } from "../globalPath.js";
+
+export const fileRename = async () => {
+  const sourcePath = `${__dirname(import.meta.url)}/files`;
+  const targetFile = "wrongFilename.txt";
+  const finalFileName = "properFilename.md";
+
+  rename(
+    `${sourcePath}/${targetFile}`,
+    `${sourcePath}/${finalFileName}`,
+    (err) => {
+      if (err) {
+        throw new Error("FS operation failed");
+      }
+    }
+  );
+};
+
+fileRename();

src/globalPath.js

@@ -0,0 +1,13 @@
+import { fileURLToPath } from "url";
+import { dirname } from "path";
+
+function __filename(metaUrl) {
+  return fileURLToPath(metaUrl);
+}
+
+function __dirname(metaUrl) {
+  const fileName = fileURLToPath(metaUrl);
+  return dirname(fileName);
+}
+
+export { __filename, __dirname };

src/hash/calcHash.js

@@ -1,3 +1,19 @@
+import { readFileSync } from "fs";
+import crypto from "crypto";
+import { __dirname } from "../globalPath.js";
+
 export const calculateHash = async () => {
-    // Write your code here 
-};
+  const sourcePath = `${__dirname(
+    import.meta.url
+  )}/files/fileToCalculateHashFor.txt`;
+
+  const data = readFileSync(sourcePath, "utf8");
+  return crypto.createHash("sha256").update(data).digest("hex");
+};
+
+async function printHash() {
+  const hash = await calculateHash();
+  console.log(hash);
+}
+
+printHash();

src/modules/cjsToEsm.mjs

@@ -0,0 +1,41 @@
+import path from "path";
+import { release, version } from "os";
+import { createServer as createServerHttp } from "http";
+import "./files/c.js";
+
+import { readFile } from "fs/promises";
+import { fileURLToPath } from "url";
+import { dirname } from "path";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = dirname(__filename);
+
+const aJSON = JSON.parse(
+  await readFile(new URL("./files/a.json", import.meta.url))
+);
+const bJSON = JSON.parse(
+  await readFile(new URL("./files/b.json", import.meta.url))
+);
+
+const random = Math.random();
+
+let unknownObject;
+
+if (random > 0.5) {
+  unknownObject = aJSON;
+} else {
+  unknownObject = bJSON;
+}
+
+console.log(`Release ${release()}`);
+console.log(`Version ${version()}`);
+console.log(`Path segment separator is "${path.sep}"`);
+
+console.log(`Path to current file is ${__filename}`);
+console.log(`Path to current directory is ${__dirname}`);
+
+const createMyServer = createServerHttp((_, res) => {
+  res.end("Request accepted");
+});
+
+export { unknownObject, createMyServer };