Odwrotne Proxy

Free proxies, while seemingly profitable and attractive, are actually not very effective. They cannot boast of security, speed, stability and acceptable duration of work. Qualitative and reliable proxies require a certain investment, but they can be obtained from companies that have a good reputation as proxy service providers. You can also find out about all the nuances of proxy selection with the help of special proxy databases.

When scraping paginated content, fetching the "next page" usually involves extracting the URL of the next page from the HTML of the current page. In PHP, you can use a library like Simple HTML DOM Parser to parse HTML and extract the URL for the next page.

Here's an example of how you might scrape the next page URL using PHP

Install Simple HTML DOM Parser:

You can download it from sourceforge and include it in your project, or use Composer:

composer require sunra/php-simple-html-dom-parser

Write a PHP script to scrape the next page URL:

find('a.next-page-link', 0);

    if ($nextPageLink) {
        // Extract the href attribute (URL) from the link
        $nextPageUrl = $nextPageLink->href;
        return $nextPageUrl;
    } else {
        return null; // No next page link found
    }
}

// Example usage
$currentUrl = 'https://example.com/page1'; // Replace with the URL of the current page
$nextPageUrl = scrapeNextPageUrl($currentUrl);

if ($nextPageUrl) {
    echo "Next Page URL: $nextPageUrl";
} else {
    echo "No Next Page URL found.";
}

Replace the $currentUrl variable with the URL of the current page.

Adjust the HTML element selector ('a.next-page-link') based on the structure of the website you are scraping.

Run the script:

Execute the PHP script to see the URL of the next page.

To scrape JSON data using RxJava in a Java application, you can use the RxJava library along with an HTTP client library to make requests. Below is an example using RxJava2 and OkHttp to scrape JSON data from a URL asynchronously.

Add Dependencies

Add the following dependencies to your project:

    io.reactivex.rxjava2
    rxjava
    2.x.y 




    com.squareup.okhttp3
    okhttp
    4.x.y 

Write the Code:

import io.reactivex.Observable;
import io.reactivex.schedulers.Schedulers;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class JsonScrapingExample {

    public static void main(String[] args) {
        String url = "https://api.example.com/data"; // Replace with your JSON API URL

        // Create an Observable that emits a single item (the URL)
        Observable.just(url)
                .observeOn(Schedulers.io()) // Specify the IO thread for network operations
                .map(JsonScrapingExample::fetchJson)
                .subscribe(
                        jsonData -> {
                            // Process the JSON data (replace this with your scraping logic)
                            System.out.println("Scraped JSON data: " + jsonData);
                        },
                        Throwable::printStackTrace
                );
    }

    // Function to fetch JSON data using OkHttp
    private static String fetchJson(String url) throws Exception {
        OkHttpClient client = new OkHttpClient();
        Request request = new Request.Builder()
                .url(url)
                .build();

        try (Response response = client.newCall(request).execute()) {
            if (!response.isSuccessful()) {
                throw new Exception("Failed to fetch JSON. HTTP Code: " + response.code());
            }

            // Return the JSON data as a string
            return response.body().string();
        }
    }
}

2. • Replace the url variable with the actual URL of the JSON API you want to scrape.
   • The fetchJson function uses OkHttp to make an HTTP request and fetch the JSON data.

3. Run the Code:

   • Execute the Java code to fetch and process the JSON data asynchronously using RxJava.

This example uses RxJava's Observable to create an asynchronous stream of events. The observeOn(Schedulers.io()) part specifies that the network operation (fetchJson) should run on the IO thread to avoid blocking the main thread.

Make sure to handle exceptions appropriately and adjust the code based on the structure of the JSON API you are working with.

To determine if your computer is using a proxy server, you can follow these steps for Windows and macOS:

For Windows:
- Press the Windows key + R to open the Run dialog box.
- Type "inetcpl.cpl" (without quotes) in the Run dialog box and press Enter.
- In the Internet Properties window, go to the Connections tab.
- Click on the "LAN settings" button.
- In the LAN Settings window, if there is a checkmark in the "Use a proxy server for your LAN" box, it means your computer is using a proxy server.

For macOS:
- Click on the Apple menu in the top-left corner of your screen.
- Select "System Preferences" from the dropdown menu.
- Click on "Network" in the System Preferences window.
- Select the network connection you are using (e.g., Wi-Fi, Ethernet) from the left pane.
- Click on the "Advanced" button.
- In the Advanced window, go to the "Proxies" tab to see if there is any proxy settings configured for your network connection. If there are settings, it means your computer is using a proxy server.

Start the program and add a template. Click on it twice to open a window. Here you need to specify the path to the file with the proxy and save the settings. Enter the following format in the file: HTTPS - 195.3.218.232:8000 - if the proxy is bound to your IP, or login:[email protected]:8000 - if you use a proxy with username and password authentication. Under "Settings" click on "Default", or fill everything in manually, and then confirm the changes you made.