如何在 Python 3 中使用 Selenium 模块 (FireFox) 下载 PDF

Question

我想从在线杂志下载 PDF。要打开它，必须先登录。然后打开 PDF 并下载。

以下是我的代码。它可以登录页面，也可以打开PDF。但是无法下载 PDF，因为我不确定如何模拟单击保存。我用火狐。

import os, time
from selenium import webdriver
from bs4 import BeautifulSoup

# Use firefox dowmloader to get file
fp = webdriver.FirefoxProfile()
fp.set_preference("browser.download.folderList",2)
fp.set_preference("browser.download.manager.showWhenStarting",False)
fp.set_preference("browser.download.dir", 'D:/eBooks/Stocks_andCommodities/2008/Jul/')
fp.set_preference("browser.helperApps.neverAsk.saveToDisk", "application/pdf")
fp.set_preference("pdfjs.disabled", "true")

# disable Adobe Acrobat PDF preview plugin
fp.set_preference("plugin.scan.plid.all", "false")
fp.set_preference("plugin.scan.Acrobat", "99.0")

browser = webdriver.Firefox(firefox_profile=fp)

# Get the login web page
web_url = 'http://technical.traders.com/sub/sublogin2.asp'
browser.get(web_url)

# SImulate the authentication
user_name = browser.find_element_by_css_selector('#SubID > input[type="text"]')
user_name.send_keys("thomas2003@test.net")
password = browser.find_element_by_css_selector('#SubName > input[type="text"]')
password.send_keys("LastName")
time.sleep(2)
submit = browser.find_element_by_css_selector('#SubButton > input[type="submit"]')
submit.click()
time.sleep(2)

# Open the PDF for downloading
url = 'http://technical.traders.com/archive/articlefinal.asp?file=\V26\C07\\131INTR.pdf'
browser.get(url)
time.sleep(10)

# How to simulate the Clicking to Save/Download the PDF here?

Answer 1

您不应该在浏览器中打开文件。一旦你有了文件的 url。获取所有 cookie 的请求会话

def get_request_session(driver):
    import requests
    session = requests.Session()
    for cookie in driver.get_cookies():
        session.cookies.set(cookie['name'], cookie['value'])

    return session

一旦你有会话，你可以使用相同的下载文件

url = 'http://technical.traders.com/archive/articlefinal.asp?file=\V26\C07\\131INTR.pdf'
session = get_request_session(driver)
r = session.get(url, stream=True)
chunk_size = 2000
with open('/tmp/mypdf.pdf', 'wb') as file:
    for chunk in r.iter_content(chunk_size):
        file.write(chunk)

Answer 2

除了Tarun的解决方案，你还可以通过js下载文件，并存储为blob。然后您可以通过 selinium 的执行脚本将数据提取到 python 中，如 in this answer 所示。

在你的情况下，

url = 'http://technical.traders.com/archive/articlefinal.asp?file=\V26\C07\\131INTR.pdf'
browser.execute_script("""
    window.file_contents = null;
    var xhr = new XMLHttpRequest();
    xhr.responseType = 'blob';
    xhr.onload = function() {
        var reader  = new FileReader();
        reader.onloadend = function() {
            window.file_contents = reader.result;
        };
        reader.readAsDataURL(xhr.response);
    };
    xhr.open('GET', %(download_url)s);
    xhr.send();
""".replace('\r\n', ' ').replace('\r', ' ').replace('\n', ' ') % {
    'download_url': json.dumps(url),
})

现在您的数据以 blob 形式存在于窗口对象上，因此您可以轻松地将其提取到 python 中：

time.sleep(3)
downloaded_file = driver.execute_script("return (window.file_contents !== null ? window.file_contents.split(',')[1] : null);")
with open('/Users/Chetan/Desktop/dummy.pdf', 'wb') as f:
    f.write(base64.b64decode(downloaded_file))

Answer 3

试试

  import urllib    
  file_path = "<FILE PATH TO SAVE>"
  urllib.urlretrieve(<pdf_link>,file_path)