Can Scraper (Rust) handle cookies and sessions automatically?

Scraper is a Rust crate that provides an HTML parsing and querying library, which is essentially a Rust port of the Python BeautifulSoup library. Scraper itself is designed for extracting data from HTML documents and does not handle HTTP requests directly. Therefore, it does not manage cookies and sessions automatically.

To handle cookies and sessions in Rust, you typically use an HTTP client library like reqwest, which has features for handling cookies, sessions, and other HTTP-related tasks. By using reqwest, you can manage cookies and sessions and then pass the HTML content to Scraper for parsing and extraction.

Here is a simple example of how you could use reqwest with scraper to handle cookies and sessions:

use reqwest::header::{HeaderMap, USER_AGENT, COOKIE};
use scraper::{Html, Selector};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Create a client instance with cookie store enabled
    let client = reqwest::Client::builder()
        .cookie_store(true)
        .build()?;

    // Define the URL and the User-Agent
    let url = "http://example.com/login";
    let user_agent = "Your Custom User Agent";

    // Create headers and include the User-Agent
    let mut headers = HeaderMap::new();
    headers.insert(USER_AGENT, user_agent.parse().unwrap());

    // Perform the login request with form data (as an example)
    let form = [("username", "yourusername"), ("password", "yourpassword")];
    let res = client.post(url)
        .headers(headers)
        .form(&form)
        .send()
        .await?;

    // After login, cookies will be stored in the client instance.
    // Now you can make another request to a page that requires you to be logged in.
    let protected_url = "http://example.com/protected";
    let content = client.get(protected_url).send().await?.text().await?;

    // Use Scraper to parse the HTML content
    let document = Html::parse_document(&content);
    let selector = Selector::parse("div.protected-content").unwrap();

    // Extract information using the selector
    for element in document.select(&selector) {
        let protected_content = element.inner_html();
        println!("Protected Content: {}", protected_content);
    }

    Ok(())
}

In the above Rust code, we use the reqwest crate with the cookie_store feature to handle cookies automatically. We perform a POST request to a login URL with form data, and if the login is successful, the server will set cookies that reqwest will store and send in subsequent requests. Then, we make another request to a protected page that requires a session, and finally, we parse the HTML content using the scraper crate.

Remember that when dealing with cookies and sessions, you must respect the website's terms of service and privacy policy. Automated login and data extraction without permission may violate the terms and can be considered unethical or even illegal in some jurisdictions. Always ensure you have the right to scrape the content you are targeting.