Selenium Python Chrome下载PDF被拦截问题求助

我尝试从http://www.cub.org.br/cub-m2-estadual/CE/下载PDF文件，点击“Gerar Relatório em PDF”（生成PDF报告）时，Chrome提示文件不可信而拦截下载。已尝试多种Selenium Python配置绕过安全提示，但问题仍未解决，代码如下：

import os
import time
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
from selenium.webdriver.support.ui import Select
from selenium.webdriver.common.by import By

# Pasta Padrão
download_dir = os.getcwd()

# Instância Chrome Options
chrome_options = Options()

# Configurando Chrome Para Permitir Dowload do PDF
chrome_options.add_argument("--disable-extensions")
chrome_options.add_argument("--disable-plugins")
chrome_options.add_argument("--incognito")
chrome_options.add_argument("--no-sandbox")
chrome_options.add_argument("--disable-gpu")
chrome_options.add_argument("--disable-popup-blocking")
chrome_options.add_argument("--ignore-certificate-errors")
chrome_options.add_argument("--allow-insecure-localhost")

# Pasta Download
prefs = {
    "download.default_directory": download_dir,
    "download.prompt_for_download": False,
    "plugins.always_open_pdf_externally": True,
    "download.open_pdf_in_system_reader": False,
    "profile.default_content_settings.popups": 0,
    "safebrowsing.enabled": True
}
chrome_options.add_experimental_option('prefs', prefs)

# Instância Chrome
driver = webdriver.Chrome(options=chrome_options)
driver.maximize_window()
time.sleep(2)

# Acessando Site
driver.get('http://www.cub.org.br/cub-m2-estadual/CE/')
time.sleep(2)

# Verifica Anos Disponíveis
# Na Lista Suspensa
lista_suspensa = Select(driver.find_element(By.NAME, 'ano'))
opcoes_lista_suspensa = [item.text for item in lista_suspensa.options]

# Seleciona Primeiro Elemento da Lista
# Que é o Ano Mais Recente
lista_suspensa.select_by_value(opcoes_lista_suspensa[0])

# Clicando Baixar Relatório
download_file_xpath = '//*[@id="wrapper"]/div/div[1]/div/div[1]/div[2]/div/form/input[2]'
driver.find_element(By.XPATH, download_file_xpath).click()

解决方案 #

• 关闭安全浏览保护：当前配置中safebrowsing.enabled设为True会触发Chrome的安全拦截，修改为False并添加禁用下载保护的配置：

  prefs = {
      "download.default_directory": download_dir,
      "download.prompt_for_download": False,
      "plugins.always_open_pdf_externally": True,
      "download.open_pdf_in_system_reader": False,
      "profile.default_content_settings.popups": 0,
      "safebrowsing.enabled": False,
      "safebrowsing.disable_download_protection": True
  }
  

• 添加安全相关启动参数：在ChromeOptions中加入以下参数，进一步禁用安全检查机制：

  chrome_options.add_argument("--safebrowsing-disable-download-protection")
  chrome_options.add_argument("--safebrowsing-disable-extension-blacklist")
  

• 替换隐式等待为显式等待：time.sleep()依赖固定时长，改用显式等待确保元素加载完成后再操作，避免页面未就绪导致的异常：

  from selenium.webdriver.support.ui import WebDriverWait
  from selenium.webdriver.support import expected_conditions as EC
  
  # 等待下拉框加载完成
  lista_suspensa = Select(WebDriverWait(driver, 10).until(
      EC.presence_of_element_located((By.NAME, 'ano'))
  ))
  
  # 等待下载按钮可点击后执行点击
  download_btn = WebDriverWait(driver, 10).until(
      EC.element_to_be_clickable((By.XPATH, '//*[@id="wrapper"]/div/div[1]/div/div[1]/div[2]/div/form/input[2]'))
  )
  download_btn.click()
  

• 检查下载目录权限：确保脚本对指定的下载目录有写入权限，权限不足可能导致下载失败并被Chrome判定为安全风险。

内容的提问来源于stack exchange，提问作者Felipe Gomes