HowProgrammingWorks · diophants · Jan 16, 2024
diff --git a/JavaScript/4-all/readme.md b/JavaScript/4-all/readme.md
@@ -0,0 +1,22 @@
+## Вопросы
+
+- Зачем нужно объявлять константу STATIC_FILE_LENGTH?
+- Как вызвать pathTraversal что бы он был равен true?
+- Можно ли утверждать, чем больше проверок на безопасность тем лучше,
+  или в некоторых случаях они создают уязвимость?
+
+## Упражнения
+
+1. Обработайте ошибки:
+
+- когда файла не найден; &#10003;
+- когда нет прав на чтение файла или каталога; &#10007;
+- когда происходит попытка чтения файла из каталога выше. &#10007;
+
+2. Создайте шаблоны страниц с ошибками в специальном каталоге. &#10003;
+3. Перепишите те места, которые возможно с использованием `fs.promises`. &#10003;
+4. Объедините все примеры в один: &#10003;
+
+- отдача индекса каталога; &#10003;
+- кеширование; &#10003;
+- обработка ошибок. &#10003;
diff --git a/JavaScript/4-all/server.js b/JavaScript/4-all/server.js
@@ -0,0 +1,86 @@
+'use strict';
+
+const http = require('node:http');
+const fs = require('node:fs').promises;
+const path = require('node:path');
+
+const PORT = 8000;
+
+const STATIC_PATH = path.join(process.cwd(), './static');
+
+const MIME_TYPE = {
+  default: 'application/octet-stream',
+  html: 'text/html; charset=UTF-8',
+  js: 'application/javascript; charset=UTF-8',
+  css: 'text/css',
+  png: 'image/png',
+  jpg: 'image/jpeg',
+  ico: 'image/x-icon',
+};
+
+const cache = new Map();
+
+const cacheFile = async (filePath) => {
+  const key = filePath.substring(STATIC_PATH.length).replace(/\\/g, '/');
+  const value = await fs.readFile(filePath);
+  cache.set(key, value);
+};
+
+const cacheDirectory = async (directoryPath) => {
+  const files = await fs.readdir(directoryPath, { withFileTypes: true });
+  for (const file of files) {
+    const filePath = path.join(file.path, file.name);
+    if (file.isDirectory()) cacheDirectory(filePath);
+    else cacheFile(filePath);
+  }
+  const key = directoryPath.substring(STATIC_PATH.length).replace(/\\/g, '/');
+  cache.set(
+    key || '/',
+    files.map((file) => file.name)
+  );
+};
+
+cacheDirectory(STATIC_PATH);
+
+const folderIndex = (url) => {
+  const items = cache.get(url);
+  if (url !== '/' && items[0] !== '../') items.unshift('../');
+  const list = items
+    .map((el) => {
+      const addres = path.join(url, el);
+      return `<li><a href="http://localhost:${PORT}${addres}">${el}</a></li>`;
+    })
+    .join('\n');
+  const file = `<h2>Directory files: <h2> <ul>${list}</ul>`;
+  return file;
+};
+
+const prepareFile = (url) => {
+  const filePath = path.join(STATIC_PATH, url);
+  const pathTraversal = !filePath.startsWith(STATIC_PATH);
+  // console.log(pathTraversal)
+  const exists = cache.get(url);
+  const found = !pathTraversal && !!exists;
+  let cachePath = url;
+  if (!found) cachePath = '/errors/404.html';
+  if (pathTraversal) cachePath = '/errors/traversal.html'; // Не знаю как установить true через браузер
+  if (!'readingRights') cachePath = '/errors/no-reading.html'; // Не представляю как это раелизовать без авторизации пользователя
+  const errorPath =
+    cachePath.startsWith('/errors/') && cachePath.endsWith('.html');
+  const isDirectory = exists instanceof Array && !errorPath;
+  const ext = path.extname(cachePath).substring(1);
+  const content = isDirectory ? folderIndex(cachePath) : cache.get(cachePath);
+  return { found, ext: isDirectory ? 'html' : ext, content };
+};
+
+http
+  .createServer((req, res) => {
+    const file = prepareFile(req.url);
+    const mimeType = MIME_TYPE[file.ext] || MIME_TYPE.default;
+    const statusCode = file.found ? 200 : 404;
+    res.writeHead(statusCode, { 'content-type': mimeType });
+    res.end(file.content);
+  })
+  .listen(PORT, () =>
+    console.log(`Server is running: http://localhost:${PORT}`)
+  );
diff --git a/JavaScript/4-all/static/errors/404.html b/JavaScript/4-all/static/errors/404.html
@@ -0,0 +1 @@
+<h2>file is not exists!</h2>
diff --git a/JavaScript/4-all/static/errors/no-reading.html b/JavaScript/4-all/static/errors/no-reading.html
@@ -0,0 +1 @@
+<h2>You do not have permission to read this directory!</h2>
diff --git a/JavaScript/4-all/static/errors/traversal.html b/JavaScript/4-all/static/errors/traversal.html
@@ -0,0 +1 @@
+<h1>Occurrd traversal path!</h1>
diff --git a/JavaScript/4-all/static/favicon.ico b/JavaScript/4-all/static/favicon.ico
diff --git a/JavaScript/4-all/static/favicon.png b/JavaScript/4-all/static/favicon.png
diff --git a/JavaScript/4-all/static/images/Diophant.png b/JavaScript/4-all/static/images/Diophant.png
diff --git a/JavaScript/4-all/static/images/channel-xyz.jpg b/JavaScript/4-all/static/images/channel-xyz.jpg
diff --git a/JavaScript/4-all/static/index.html b/JavaScript/4-all/static/index.html
@@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta
+      name="viewport"
+      content="width=device-width, initial-scale=1.0"
+    />
+    <title>Document</title>
+    <link rel="stylesheet" href="styles/style.css" />
+  </head>
+  <body>
+    <button class="hello">hello</button>
+  </body>
+</html>
diff --git a/JavaScript/4-all/static/js/init.js b/JavaScript/4-all/static/js/init.js
@@ -0,0 +1 @@
+console.log('hello');
diff --git a/JavaScript/4-all/static/styles/style.css b/JavaScript/4-all/static/styles/style.css
@@ -0,0 +1,6 @@
+.hello {
+  background-color: black;
+  width: 200;
+  height: 60;
+  color: white;
+}
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		<h2>You do not have permission to read this directory!</h2>