Книги
TypeScript
Розділ 11. HTML та веб
Завантаження веб-сторінки

TypeScript:
Завантаження веб-сторінки

How to (Як це зробити):

To download a web page in TypeScript, you’ll need node-fetch. Install it with npm install node-fetch. Here’s how you use it:

import fetch from 'node-fetch';

async function downloadPage(url: string): Promise<string> {
    try {
        const response = await fetch(url);
        return response.ok ? await response.text() : 'Failed to load page';
    } catch (error) {
        return 'Error: ' + error;
    }
}

downloadPage('https://www.example.com').then(console.log);

Sample output for a successful page load might be the HTML contents, and for an error, ‘Error: TypeError: Failed to fetch’.

Deep Dive (Поглиблене Вивчення):

Historically, downloading a web page was often done with XMLHttpRequest in the browser, or with modules like http or https in Node.js. fetch API provides a cleaner, promise-based way to make web requests, and node-fetch is essentially node’s implementation of what fetch does in the browser.

Alternatives to node-fetch include axios or libraries like got. Each has its pros and cons in terms of features, syntax, and performance.

Understanding HTTP status codes and headers is crucial. They tell you if your request was successful (200 series), redirected (300 series), had client errors (400 series), or server errors (500 series).

See Also (Див. також):

Аналіз HTML