Task "Nodejs basics"

package.json

@@ -7,23 +7,23 @@
   },
   "type": "module",
   "scripts": {
-    "cli:args": "node src/cli/args.js --some-arg value1 --other 1337 --arg2 42",
-    "cli:env": "npx cross-env SOME=any RSS_foo=bar RSS_bar=baz node src/cli/env.js",
-    "cp": "node src/cp/cp.js",
-    "fs:copy": "node src/fs/copy.js",
-    "fs:create": "node src/fs/create.js",
-    "fs:delete": "node src/fs/delete.js",
-    "fs:list": "node src/fs/list.js",
-    "fs:read": "node src/fs/read.js",
-    "fs:rename": "node src/fs/rename.js",
-    "hash": "node src/hash/calcHash.js",
+    "cli:args": "node src/cli/args.mjs --some-arg value1 --other 1337 --arg2 42",
+    "cli:env": "npx cross-env SOME=any RSS_foo=bar RSS_bar=baz node src/cli/env.mjs",
+    "cp": "node src/cp/cp.mjs",
+    "fs:copy": "node src/fs/copy.mjs",
+    "fs:create": "node src/fs/create.mjs",
+    "fs:delete": "node src/fs/delete.mjs",
+    "fs:list": "node src/fs/list.mjs",
+    "fs:read": "node src/fs/read.mjs",
+    "fs:rename": "node src/fs/rename.mjs",
+    "hash": "node src/hash/calcHash.mjs",
     "modules": "node src/modules/esm.mjs",
-    "streams:read": "node src/streams/read.js",
-    "streams:transform": "node src/streams/transform.js",
-    "streams:write": "node src/streams/write.js",
-    "wt": "node src/wt/main.js",
-    "zip:compress": "node src/zip/compress.js",
-    "zip:decompress": "node src/zip/decompress.js"
+    "streams:read": "node src/streams/read.mjs",
+    "streams:transform": "node src/streams/transform.mjs",
+    "streams:write": "node src/streams/write.mjs",
+    "wt": "node src/wt/main.mjs",
+    "zip:compress": "node src/zip/compress.mjs",
+    "zip:decompress": "node src/zip/decompress.mjs"
   },
   "repository": {
     "type": "git",

src/cli/args.mjs

@@ -0,0 +1,22 @@
+const FIRST_ARGUMENT_INDEX = 2;
+const VARIABLE_PREFIX = '--';
+
+const isVariable = (argument) => argument.startsWith(VARIABLE_PREFIX);
+
+const getVariableValueFromArguments = (args, index) => {
+  if ((args.length <= index + 1) || isVariable(args[index + 1])) return '';
+  return args[index + 1];
+}
+
+const parseArgs = () => {
+  const args = process.argv.slice(FIRST_ARGUMENT_INDEX);
+  const result = [];
+
+  args.forEach((argument, index) => {
+    if (isVariable(argument)) result.push(`${argument} is ${getVariableValueFromArguments(args, index)}`);
+  });
+
+  console.log(result.join(', '));
+};
+
+parseArgs();

src/cli/env.mjs

@@ -0,0 +1,18 @@
+const VARIABLE_RSS_PREFIX = 'RSS_';
+const RESULT_STRING_DELIMITER = '; ';
+
+const isRSSEnvVariable = (envVariableName) => envVariableName.startsWith(VARIABLE_RSS_PREFIX);
+const getEnvVariablePairString = (envVariableName, envVariablesObject) => `${envVariableName}=${envVariablesObject[envVariableName]}`;
+
+const parseEnv = () => {
+  const envRSSVariablesPairsStrings  = [];
+  const envVariablesObject = process.env;
+
+  for (let envVariableName in envVariablesObject) {
+    if (isRSSEnvVariable(envVariableName)) envRSSVariablesPairsStrings.push(getEnvVariablePairString(envVariableName, envVariablesObject));
+  }
+
+  console.log(envRSSVariablesPairsStrings.join(RESULT_STRING_DELIMITER));
+};
+
+parseEnv();

src/common/constants.mjs

@@ -0,0 +1 @@
+export const FILES_DIR_NAME = 'files';

src/common/helper.mjs

@@ -0,0 +1,3 @@
+import { join } from 'path';
+
+export const getPath = (dirname, subDirName, fileName = '') => join(dirname, subDirName, fileName);

src/cp/cp.mjs

@@ -0,0 +1,13 @@
+import { fork as childProcessFork } from 'child_process';
+
+import { getPath } from '../common/helper.mjs';
+import { FILES_DIR_NAME } from '../common/constants.mjs';
+
+const SCRIPT_FILE_PATH = 'script.js';
+
+const spawnChildProcess = (args) => {
+  const scriptPath = getPath(import.meta.dirname, FILES_DIR_NAME, SCRIPT_FILE_PATH);
+  childProcessFork(scriptPath, args, { stdio: [0, 1, 2, 'ipc'] });
+};
+
+spawnChildProcess(['first', 'the second', 3, [4, 4, 4, 4]]);

src/fs/common/constants.mjs

@@ -0,0 +1,5 @@
+import { FILES_DIR_NAME } from '../../common/constants.mjs';
+
+export const ERROR_MESSAGE = 'FS operation failed';
+
+export { FILES_DIR_NAME };

src/fs/common/helpers.mjs

@@ -0,0 +1,17 @@
+import { access as fsPromisesAccess } from 'fs/promises';
+
+import { getPath } from '../../common/helper.mjs';
+import { FILES_DIR_NAME } from './constants.mjs';
+
+export const getFilePath = (dirname, fileName) => getPath(dirname, FILES_DIR_NAME, fileName);
+
+export const isFileExist = async (filePath) => {
+  try {
+    await fsPromisesAccess(filePath);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+export { getPath };

src/fs/copy.mjs

@@ -0,0 +1,28 @@
+import { cp as fsPromisesCopy } from 'fs/promises';
+
+import { getPath } from './common/helpers.mjs';
+import { ERROR_MESSAGE, FILES_DIR_NAME } from './common/constants.mjs';
+
+const DESTINATION_FOLDER_NAME = 'files_copy';
+
+const copy = async () => {
+  const currentDirectoryPath = import.meta.dirname;
+
+  const filesFolderPath = getPath(currentDirectoryPath, FILES_DIR_NAME);
+  const destinationFolderPath = getPath(currentDirectoryPath, DESTINATION_FOLDER_NAME);
+
+  try {
+    await fsPromisesCopy( 
+      filesFolderPath,
+      destinationFolderPath,
+      { 
+        errorOnExist: true,
+        force: false,
+        recursive: true
+      });
+  } catch { 
+    throw new Error(ERROR_MESSAGE); 
+  } 
+};
+
+await copy();

src/fs/create.mjs

@@ -0,0 +1,19 @@
+import { writeFile as fsPromisesWriteFile } from 'fs/promises';
+
+import { getFilePath } from './common/helpers.mjs';
+import { ERROR_MESSAGE } from './common/constants.mjs';
+
+const CONTENT_TO_WRITE = 'I am fresh and young';
+const FILE_NAME = 'fresh.txt';
+
+const create = async () => {
+  const outputFilePath = getFilePath(import.meta.dirname, FILE_NAME);
+
+  try {
+    await fsPromisesWriteFile(outputFilePath, CONTENT_TO_WRITE, { flag: 'wx' });
+  } catch { 
+    throw new Error(ERROR_MESSAGE); 
+  }
+};
+
+await create();

src/fs/delete.mjs

@@ -0,0 +1,18 @@
+import { rm as fsPromisesRemove } from 'fs/promises';
+
+import { getFilePath } from './common/helpers.mjs';
+import { ERROR_MESSAGE } from './common/constants.mjs';
+
+const FILE_NAME = 'fileToRemove.txt';
+
+const remove = async () => {
+  const filePath = getFilePath(import.meta.dirname, FILE_NAME);
+
+  try {
+    await fsPromisesRemove(filePath);
+  } catch {
+    throw new Error(ERROR_MESSAGE);
+  }
+};
+
+await remove();

src/fs/list.mjs

@@ -0,0 +1,17 @@
+import { readdir as fsPromisesReadDir } from 'fs/promises';
+
+import { getPath } from './common/helpers.mjs';
+import { ERROR_MESSAGE, FILES_DIR_NAME } from './common/constants.mjs';
+
+const list = async () => {
+  const filesPath = getPath(import.meta.dirname, FILES_DIR_NAME);
+
+  try {
+    const dirContent = await fsPromisesReadDir(filesPath, { recursive: true });
+    console.log(dirContent);
+  } catch {
+    throw new Error(ERROR_MESSAGE);
+  }
+};
+
+await list();

src/fs/read.mjs

@@ -0,0 +1,20 @@
+import { readFile as fsPromisesReadFile } from 'fs/promises';
+
+import { getFilePath } from './common/helpers.mjs';
+import { ERROR_MESSAGE } from './common/constants.mjs';
+
+const FILE_NAME = 'fileToRead.txt';
+const ENCODING_UTF8 = 'utf-8';
+
+const read = async () => {
+  const filePath = getFilePath(import.meta.dirname, FILE_NAME);
+
+  try {
+    const fileContent = await fsPromisesReadFile(filePath, ENCODING_UTF8);
+    console.log(fileContent);
+  } catch {
+    throw new Error(ERROR_MESSAGE);
+  }
+};
+
+await read();

src/fs/rename.mjs

@@ -0,0 +1,23 @@
+import { rename as fsPromisesRename } from 'fs/promises';
+
+import { getFilePath, isFileExist } from './common/helpers.mjs';
+import { ERROR_MESSAGE } from './common/constants.mjs';
+
+const FILE_NAMES = {
+  WRONG: 'wrongFilename.txt',
+  PROPER: 'properFilename.md'
+};
+
+const rename = async () => {
+  const wrongFilePath = getFilePath(import.meta.dirname, FILE_NAMES.WRONG);
+  const properFilePath = getFilePath(import.meta.dirname, FILE_NAMES.PROPER);
+
+  try {
+    if (await isFileExist(properFilePath)) throw new Error();
+    await fsPromisesRename(wrongFilePath, properFilePath);
+  } catch {
+    throw new Error(ERROR_MESSAGE);
+  }
+};
+
+await rename();

src/hash/calcHash.mjs

@@ -0,0 +1,38 @@
+import { Writable } from 'stream';
+import { pipeline as streamPromisesPipeline } from 'stream/promises';
+import { open as fsPromisesOpen } from 'fs/promises';
+import { createHash as cryptoCreateHash } from 'crypto';
+
+import { getPath } from '../common/helper.mjs';
+import { FILES_DIR_NAME } from '../common/constants.mjs';
+
+const HASH_TYPE = 'sha256';
+const INPUT_FILE_PATH = 'fileToCalculateHashFor.txt';
+
+class ConsoleLoggerStream extends Writable {
+  constructor() {
+    super();
+  }
+
+  _write(chunk) {
+    console.log(chunk.toString('hex'));
+  }
+}
+
+const consoleLoggerStream = new ConsoleLoggerStream();
+
+const calculateHash = async () => {
+  const inputFilePath = getPath(import.meta.dirname, FILES_DIR_NAME, INPUT_FILE_PATH);
+  const fd = await fsPromisesOpen(inputFilePath);
+  const inputStream = fd.createReadStream();
+
+  const calculateHashTransformStream = cryptoCreateHash(HASH_TYPE);
+
+  await streamPromisesPipeline(
+    inputStream,
+    calculateHashTransformStream,
+    consoleLoggerStream
+  );
+};
+
+calculateHash();