Nginx Reverse Proxy

Data parsing in most cases refers to the collection of technical or other information. For example, a local proxy server can be used for parsing "log data". That is, information about the work of the site, the application, which in the future will be useful for developers to find and fix various bugs.

When scraping a dynamic list where the content is loaded dynamically, you often need to use a web scraping library that supports interaction with JavaScript or a headless browser. The selenium library is a popular choice for this task.

Below is an example of scraping a dynamic list from a website using Python with selenium. In this example, the list items are loaded dynamically through JavaScript, and we'll use selenium to interact with the page.

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

# Replace 'your_url' with the actual URL of the page
url = 'your_url'

# Initialize the webdriver (you may need to download the appropriate webdriver for your browser)
driver = webdriver.Chrome()

# Open the webpage
driver.get(url)

# Use WebDriverWait to wait for the dynamic content to load
try:
    # Adjust the timeout and conditions based on your webpage's behavior
    WebDriverWait(driver, 10).until(
        EC.presence_of_element_located((By.XPATH, '//div[@class="your-list-item-class"]'))
    )

    # Extract the list items using XPath (adjust the XPath based on your HTML structure)
    list_items = driver.find_elements(By.XPATH, '//div[@class="your-list-item-class"]')

    # Process the list items
    for index, item in enumerate(list_items):
        print(f"Item {index + 1}: {item.text}")

finally:
    # Close the browser window
    driver.quit()

In this example:

• Replace 'your_url' with the actual URL of the page you want to scrape.
• Adjust the XPath in driver.find_elements based on the structure of your HTML. This XPath should point to the dynamic list items.

Remember to install the selenium library (pip install selenium) and download the appropriate WebDriver (e.g., ChromeDriver) for your browser.

In a Java application, the parsing of JSON data can take place in different layers depending on the architectural pattern you are following. Here are common layers where JSON parsing can occur:

1. Data Access Layer (DAO):

   • If your application follows a traditional layered architecture, you might perform JSON parsing in the Data Access Layer. In this layer, you can convert JSON data received from external sources (e.g., a RESTful API) into Java objects before persisting them to a database.

2. Service Layer:

   • JSON parsing can also be done in the Service Layer. Services may receive JSON data from various sources and convert it into domain objects or DTOs (Data Transfer Objects) before interacting with the business logic or data access layer.

3. Controller/Endpoint Layer:

   • In a web-based application, such as a Spring MVC or Spring Boot application, JSON parsing is often done in the controllers or endpoints. Incoming JSON requests from clients are converted into Java objects to be processed by the business logic.

4. Model Layer:

   • In some cases, especially when dealing with serialization/deserialization within the application itself, JSON parsing can take place in the Model Layer. For example, converting Java objects to JSON for sending responses to clients or vice versa.

5. External Libraries/Utilities:

   • JSON parsing can also be delegated to external libraries or utility classes. This is common when using libraries like Jackson, Gson, or other JSON processing libraries. These libraries provide convenient methods for converting JSON to Java objects and vice versa.

6. Middleware Layer:

   • In a middleware layer, JSON parsing might occur as part of transforming data between different systems or components. For example, in an ESB (Enterprise Service Bus) scenario where data needs to be transformed from one format to another.

7. Integration Layer:

   • If your application integrates with external services or APIs that exchange data in JSON format, the integration layer might handle JSON parsing to transform the data into a format suitable for internal processing.

The choice of the layer depends on your application's design, the responsibilities of each layer, and the architectural patterns you are following. In modern Java applications, using dedicated JSON processing libraries like Jackson or Gson is a common practice, and the parsing often occurs in the layers that interact with external data sources or clients.

In JavaScript with Selenium, you can save and reuse cookies using the WebDriver's manage().getCookies() and manage().addCookie() methods. Here's a simple example:

const { Builder } = require('selenium-webdriver');
const firefox = require('selenium-webdriver/firefox');

// Create a new instance of the Firefox driver
const driver = new Builder()
  .forBrowser('firefox')
  .setFirefoxOptions(new firefox.Options().headless())
  .build();

// Navigate to a webpage
async function navigateToPage() {
  await driver.get('https://example.com');
}

// Save cookies
async function saveCookies() {
  const cookies = await driver.manage().getCookies();
  // Save the cookies to a file or some storage mechanism
  // For simplicity, we'll just print them here
  console.log('Cookies:', cookies);
}

// Reuse cookies
async function reuseCookies(savedCookies) {
  // Delete existing cookies
  await driver.manage().deleteAllCookies();

  // Add the saved cookies to the browser session
  for (const cookie of savedCookies) {
    await driver.manage().addCookie(cookie);
  }

  // Navigate to a page to apply the cookies
  await navigateToPage();
}

// Example usage
(async () => {
  await navigateToPage(); // Navigate to the page and set some initial cookies

  await saveCookies(); // Save the cookies

  // Close and reopen the browser or navigate to a different page
  // ...

  // Reuse the saved cookies
  await reuseCookies(savedCookies);
})();

The navigateToPage function navigates to a webpage and sets some initial cookies.

The saveCookies function retrieves the current cookies using manage().getCookies() and prints them. You would typically save them to a file or some storage mechanism.

The reuseCookies function deletes existing cookies, then adds the saved cookies back to the browser session using manage().addCookie(). It then navigates to a page to apply the cookies.

The example usage section demonstrates how to use these functions in a sequence.

On smartphones, when a proxy is turned on, the corresponding indicator (the "VPN" icon) appears in the status bar. In Windows you have to go to "Settings", open "Network and Internet". Under "Proxy Server", if the item "Manual" is activated, it means that the proxy is engaged right now.