POST请求给出空结果

Question

我已经使用POST请求在python中编写了一些代码以从网页中获取特定数据。但是，当我运行它时，除了空白控制台外，没有任何结果。我试图相应地填写请求参数。也许，我不能注意到哪些应该包含在参数中。我正在处理的页面在其右侧面板中包含多个图像。点击图片时，我在这里谈论的请求被发送到服务器，并将结果返回并显示有关其下的风味的新信息。我的目标是解析连接到每个图像的所有风味。无论如何，我试图附上所有必要的事情，以找出我失踪的事情。提前致谢。

这是我从Chrome开发者工具一定要准备POST请求：

=================================================================================== 
General: 
Request URL:https://www.optigura.com/product/ajax/details.php 
Request Method:POST 
Status Code:200 OK 

Response Headers: 
Cache-Control:no-store, no-cache, must-revalidate 
Cache-Control:max-age=0, no-cache, no-store, must-revalidate 
Connection:Keep-Alive 
Content-Encoding:gzip 
Content-Length:782 
Content-Type:text/html; charset=utf-8 

Request Headers: 
Accept:application/json, text/javascript, */*; q=0.01 
Accept-Encoding:gzip, deflate, br 
Accept-Language:en-US,en;q=0.8 
Connection:keep-alive 
Content-Length:34 
Content-Type:application/x-www-form-urlencoded 
Cookie:OGSESSID=s1qqd0euokbfrdub9pf2efubh1; _ga=GA1.2.449310094.1501502802; _gid=GA1.2.791686763.1501502802; _gat=1; __atuvc=1%7C31; __atuvs=597f1d5241db0352000; beyable-TrackingId=499b4c5b-2939-479b-aaf0-e5cd79f078cc; aaaaaaaaa066e9a68e5654b829144016246e1a736=d5758131-71db-41e1-846d-6d719d381060.1501502805122.1501502805122.$bey$https%3a%2f%2fwww.optigura.com%2fuk%2fproduct%2fgold-standard-100-whey%2f$bey$1; aaaaaaaaa066e9a68e5654b829144016246e1a736_cs=; aaaaaaaaa066e9a68e5654b829144016246e1a736_v=1.1.0; checkloc-uk=n 
Host:www.optigura.com 
Origin:https://www.optigura.com 
Referer:https://www.optigura.com/uk/product/gold-standard-100-whey/ 
User-Agent:Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36 
X-Requested-With:XMLHttpRequest 

Form Data: 
opt:flavor 
opt1:207 
opt2:47 
ip:105 
======================================================================================= 

这里就是我，试图：

import requests 
from lxml import html 

payload = {"opt":"flavor","opt1":"207","opt2":"47","ip":"105"} 
headers = {'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.81 Safari/537.36'} 
response = requests.post("https://www.optigura.com/product/ajax/details.php", params = payload, headers = headers).text 
print(response) 

原来这是链接到网页： https://www.optigura.com/uk/product/gold-standard-100-whey/

Answer 1

你应该试试下面的请求结构：

• 要发送的数据：

  data = {'opt': 'flavor', 'opt1': '207', 'opt2': '47', 'ip': 105} 
  

• 页眉：

  headers = {'X-Requested-With': 'XMLHttpRequest'} 
  

• 网址：

  url = 'https://www.optigura.com/product/ajax/details.php' 
  

• 你也需要得到饼干，所以requests.session()要求：

  s = requests.session() 
  r = s.get('https://www.optigura.com/uk/product/gold-standard-100-whey/') 
  cookies = r.cookies 
  

完成请求：

response = s.post(url, cookies=cookies, headers=headers, data=data) 

现在，您可以得到所需的一块HTML为

print(response.json()['info2']) 

输出的：

'<ul class="opt2"><li class="active"> 
        <label> 
         <input type="radio" name="ipr" value="1360" data-opt-sel="47" checked="checked" /> Delicious Strawberry - <span class="green">In Stock</span></label> 
       </li><li> 
        <label> 
         <input type="radio" name="ipr" value="1356" data-opt-sel="15" /> Double Rich Chocolate - <span class="green">In Stock</span></label> 
       </li><li> 
        <label> 
         <input type="radio" name="ipr" value="1169" data-opt-sel="16" /> Vanilla Ice Cream - <span class="green">In Stock</span></label> 
       </li></ul>' 

然后你可以使用lxml刮味值：

from lxml import html 

flavors = response.json()['info2'] 
source = html.fromstring(flavors) 

[print(element.replace(' - ', '').strip()) for element in source.xpath('//label/text()[2]')] 

输出：

Delicious Strawberry 
Double Rich Chocolate 
Vanilla Ice Cream 

Answer 2

您不在POST正文中发送值，params设置URL查询参数。使用data代替：

response = requests.post(
    "https://www.optigura.com/product/ajax/details.php", 
    data=payload, 
    headers=headers) 

您可能需要设置一个网址标头（加'Referer': 'https://www.optigura.com/uk/product/gold-standard-100-whey/'到你的头字典），并使用session object捕获和管理饼干（发出GET请求https://www.optigura.com/uk/product/gold-standard-100-whey/第一）。

通过一些实验，我注意到该网站还要求在设置X-Requested-With标题之前设置其内容。

以下工作：

with requests.session(): 
    session.get('https://www.optigura.com/uk/product/gold-standard-100-whey/') 
    headers = { 
     'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.81 Safari/537.36', 
     'Referer': 'https://www.optigura.com/uk/product/gold-standard-100-whey/', 
     'X-Requested-With': 'XMLHttpRequest' 
    } 
    response = session.post(
     "https://www.optigura.com/product/ajax/details.php", 
     data=payload, headers=headers) 

响应之际，JSON数据：

data = response.json()