我抓取受密碼保護的網站的步驟：

1. 捕獲 HTML 表單元素：用戶名 ID、密碼 ID 和登錄按鈕類
2. - 使用 requests 或 Selenium 等工具自動登錄：填寫用戶名，等待，填寫密碼，等待，點擊登錄
3. - 存儲會話 cookie 以進行身份??驗證
4. - 繼續(xù)抓取經過身份驗證的頁面

免責聲明：我已在 https://www.scrapewebapp.com/ 上為此特定用例構建了一個 API。因此，如果您想快速完成它，請使用它，否則請繼續(xù)閱讀。

讓我們使用這個例子：假設我想從我的帳戶 https://www.scrapewebapp.com/ 中抓取我自己的 API 密鑰。在此頁面上：https://app.scrapewebapp.com/account/api_key

1. 登錄頁面

首先，您需要找到登錄頁面。如果您嘗試訪問登錄后的頁面，大多數網站都會給您重定向 303，因此如果您嘗試直接抓取 https://app.scrapewebapp.com/account/api_key，您將自動獲取登錄頁面 https:// app.scrapewebapp.com/login。因此，如果尚未提供，這是自動查找登錄頁面的好方法。

好的，現(xiàn)在我們有了登錄頁面，我們需要找到添加用戶名或電子郵件以及密碼和實際登錄按鈕的位置。最好的方法是創(chuàng)建一個簡單的腳本，使用類型“電子郵件”、“用戶名”、“密碼”查找輸入的 ID，并查找類型為“提交”的按鈕。我在下面為您編寫了代碼：

from bs4 import BeautifulSoup


def extract_login_form(html_content: str):
    """
    Extracts the login form elements from the given HTML content and returns their CSS selectors.
    """
    soup = BeautifulSoup(html_content, "html.parser")

    # Finding the username/email field
    username_email = (
        soup.find("input", {"type": "email"})
        or soup.find("input", {"name": "username"})
        or soup.find("input", {"type": "text"})
    )  # Fallback to input type text if no email type is found

    # Finding the password field
    password = soup.find("input", {"type": "password"})

    # Finding the login button
    # Searching for buttons/input of type submit closest to the password or username field
    login_button = None

    # First try to find a submit button within the same form
    if password:
        form = password.find_parent("form")
        if form:
            login_button = form.find("button", {"type": "submit"}) or form.find(
                "input", {"type": "submit"}
            )
    # If no button is found in the form, fall back to finding any submit button
    if not login_button:
        login_button = soup.find("button", {"type": "submit"}) or soup.find(
            "input", {"type": "submit"}
        )

    # Extracting CSS selectors
    def generate_css_selector(element, element_type):
        if "id" in element.attrs:
            return f"#{element['id']}"
        elif "type" in element.attrs:
            return f"{element_type}[type='{element['type']}']"
        else:
            return element_type

    # Generate CSS selectors with the updated logic
    username_email_css_selector = None
    if username_email:
        username_email_css_selector = generate_css_selector(username_email, "input")

    password_css_selector = None
    if password:
        password_css_selector = generate_css_selector(password, "input")

    login_button_css_selector = None
    if login_button:
        login_button_css_selector = generate_css_selector(
            login_button, "button" if login_button.name == "button" else "input"
        )

    return username_email_css_selector, password_css_selector, login_button_css_selector


def main(html_content: str):
    # Call the extract_login_form function and return its result
    return extract_login_form(html_content)

2。使用 Selenium 實際登錄

現(xiàn)在您需要創(chuàng)建一個 selenium webdriver。我們將使用 chrome headless 來通過 Python 運行它。安裝方法如下：

# Install selenium and chromium

!pip install selenium
!apt-get update 
!apt install chromium-chromedriver

!cp /usr/lib/chromium-browser/chromedriver /usr/bin
import sys
sys.path.insert(0,'/usr/lib/chromium-browser/chromedriver')

然后實際登錄我們的網站并保存 cookie。我們將保存所有 cookie，但您只能根據需要保存身份驗證 cookie。

# Imports
from selenium import webdriver
from selenium.webdriver.common.by import By
import requests
import time

# Set up Chrome options
chrome_options = webdriver.ChromeOptions()
chrome_options.add_argument('--headless')
chrome_options.add_argument('--no-sandbox')
chrome_options.add_argument('--disable-dev-shm-usage')

# Initialize the WebDriver
driver = webdriver.Chrome(options=chrome_options)

try:
    # Open the login page
    driver.get("https://app.scrapewebapp.com/login")

    # Find the email input field by ID and input your email
    email_input = driver.find_element(By.ID, "email")
    email_input.send_keys("******@gmail.com")

    # Find the password input field by ID and input your password
    password_input = driver.find_element(By.ID, "password")
    password_input.send_keys("*******")

    # Find the login button and submit the form
    login_button = driver.find_element(By.CSS_SELECTOR, "button[type='submit']")
    login_button.click()

    # Wait for the login process to complete
    time.sleep(5)  # Adjust this depending on your site's response time


finally:
    # Close the browser
    driver.quit()

3. 存儲 Cookie

就像通過 driver.getcookies() 函數將它們保存到字典中一樣簡單。

def save_cookies(driver):
    """Save cookies from the Selenium WebDriver into a dictionary."""
    cookies = driver.get_cookies()
    cookie_dict = {}
    for cookie in cookies:
        cookie_dict[cookie['name']] = cookie['value']
    return cookie_dict

從 WebDriver 保存 cookie

cookie = save_cookies(驅動程序)

4. 從我們登錄的會話中獲取數據

在這部分中，我們將使用簡單的庫請求，但您也可以繼續(xù)使用 selenium。

現(xiàn)在我們想從此頁面獲取實際的 API：https://app.scrapewebapp.com/account/api_key。

因此，我們從請求庫創(chuàng)建一個會話并將每個 cookie 添加到其中。然后請求 URL 并打印響應文本。

def scrape_api_key(cookies):
    """Use cookies to scrape the /account/api_key page."""
    url = 'https://app.scrapewebapp.com/account/api_key'

    # Set up the session to persist cookies
    session = requests.Session()

    # Add cookies from Selenium to the requests session
    for name, value in cookies.items():
        session.cookies.set(name, value)

    # Make the request to the /account/api_key page
    response = session.get(url)

    # Check if the request is successful
    if response.status_code == 200:
        print("API Key page content:")
        print(response.text)  # Print the page content (could contain the API key)
    else:
        print(f"Failed to retrieve API key page, status code: {response.status_code}")

5. 獲取您想要的實際數據（獎勵）

我們得到了我們想要的頁面文本，但是有很多我們不關心的數據。我們只想要 api_key。

最好、最簡單的方法是使用像 ChatGPT（GPT4o 模型）這樣的人工智能。

這樣提示模型：“您是一名專家抓取工具，您只會提取從上下文中詢問的信息。我需要來自 {context} 的 api-key 值”

from bs4 import BeautifulSoup


def extract_login_form(html_content: str):
    """
    Extracts the login form elements from the given HTML content and returns their CSS selectors.
    """
    soup = BeautifulSoup(html_content, "html.parser")

    # Finding the username/email field
    username_email = (
        soup.find("input", {"type": "email"})
        or soup.find("input", {"name": "username"})
        or soup.find("input", {"type": "text"})
    )  # Fallback to input type text if no email type is found

    # Finding the password field
    password = soup.find("input", {"type": "password"})

    # Finding the login button
    # Searching for buttons/input of type submit closest to the password or username field
    login_button = None

    # First try to find a submit button within the same form
    if password:
        form = password.find_parent("form")
        if form:
            login_button = form.find("button", {"type": "submit"}) or form.find(
                "input", {"type": "submit"}
            )
    # If no button is found in the form, fall back to finding any submit button
    if not login_button:
        login_button = soup.find("button", {"type": "submit"}) or soup.find(
            "input", {"type": "submit"}
        )

    # Extracting CSS selectors
    def generate_css_selector(element, element_type):
        if "id" in element.attrs:
            return f"#{element['id']}"
        elif "type" in element.attrs:
            return f"{element_type}[type='{element['type']}']"
        else:
            return element_type

    # Generate CSS selectors with the updated logic
    username_email_css_selector = None
    if username_email:
        username_email_css_selector = generate_css_selector(username_email, "input")

    password_css_selector = None
    if password:
        password_css_selector = generate_css_selector(password, "input")

    login_button_css_selector = None
    if login_button:
        login_button_css_selector = generate_css_selector(
            login_button, "button" if login_button.name == "button" else "input"
        )

    return username_email_css_selector, password_css_selector, login_button_css_selector


def main(html_content: str):
    # Call the extract_login_form function and return its result
    return extract_login_form(html_content)

如果您想要一個簡單可靠的 API 來實現(xiàn)這一切，請嘗試我的新產品 https://www.scrapewebapp.com/

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