Python's Django application solves AJAX cross-domain access-Python Tutorial-php.cn

Home

Backend Development

Python Tutorial

Python's Django application solves AJAX cross-domain access

高洛峰

Mar 02, 2017 pm 03:50 PM

针对Django中在编写供AJAX调用的API时碰到的跨域问题,我们来总结下Python的Django应用程序解决AJAX跨域访问问题的方法,其中使用GitHub上开源分享的django-cors-headers尤其推荐

引子
使用Django在服务器端写了一个API，返回一个JSON数据。使用Ajax调用该API：

<!DOCTYPE HTML>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="maximum-scale=1.0,minimum-scale=1.0,user-scalable=0,width=device-width,initial-scale=1.0"/>
  <title>test</title>
</head>
<body>
<button onclick="showPersonInfo()">点我获取数据</button>
</body>
<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
  <script>
    function showPersonInfo(){
      $.getJSON(
        &#39;http://xxx/account/getuserinfo/&#39;,
        {username: "abc"},
        function(json) {
          var html=&#39;<br>&#39;+&#39;用户名：&#39;+json.username+&#39;<br>&#39;+&#39;姓：&#39;+json.first_name+&#39;<br>&#39;+&#39;名:&#39;+json.last_name+&#39;<br>&#39;+&#39;邮箱&#39;+json.email;    
          document.write(html);
        }
      )
    }
  </script>
</html>

但是，Chrome浏览器提示错误：

No &#39;Access-Control-Allow-Origin&#39; header is present on the requested resource.

经过一番Google发现这个问题是——CORS导致的。

什么是CORS？
CORS（跨域资源共享，Cross-Origin Resource Sharing）是一种跨域访问的机制，可以让Ajax实现跨域访问。
其实，在服务器的response header中，加入“Access-Control-Allow-Origin: *”即可支持CORS，非常的简单，apache/nginx等怎么配置，见参考文档。
举个例子：

API部署在DomainA上；
Ajax文件部署在DomainB上，Ajax文件会向API发送请求，返回数据；
用户通过DomainC访问DomainB的Ajax文件，请求数据

以上过程就发生了跨域访问。如果直接使用Ajax来请求就会失败，就像Chrome提示的：

No &#39;Access-Control-Allow-Origin&#39; header is present on the requested resource.

如何解决Ajax跨域访问问题？
解决跨域问题，有两个方法：1.使用jsonp 2.使CORS生效
使用jsonp方法，需要让服务器端放回jsonp格式的response，如Django可以加jsonp相关的decorator，如：http://www.php.cn/由于我不太喜欢这种方式，所以这里略过了，可看后面的参考资料。
使用CORS：这个用起来比较方便，现在大多数浏览器都支持了，且我web服务器完全开放给别人调用，所以比较推荐CORS。
1.使用JSONP
使用Ajax获取json数据时，存在跨域的限制。不过，在Web页面上调用js的script脚本文件时却不受跨域的影响，JSONP就是利用这个来实现跨域的传输。因此，我们需要将Ajax调用中的dataType从JSON改为JSONP（相应的API也需要支持JSONP）格式。
JSONP只能用于GET请求。

2.直接修改Django中的views.py文件
修改views.py中对应API的实现函数，允许其他域通过Ajax请求数据：

def myview(_request):
  response = HttpResponse(json.dumps({"key": "value", "key2": "value"}))
  response["Access-Control-Allow-Origin"] = "*"
  response["Access-Control-Allow-Methods"] = "POST, GET, OPTIONS"
  response["Access-Control-Max-Age"] = "1000"
  response["Access-Control-Allow-Headers"] = "*"
  return response

3.安装django-cors-headers
这里还有一各发现！在Django中，有人开发了CORS-header的middleware，只在settings.py中做一些简单的配置即可，见：http://www.php.cn/现在用起来服务器端完全开放，开启CORS，没有跨域烦恼，真爽！~
安装django-cors-headers：

pip install django-cors-headers

在settings.py中增加：

INSTALLED_APPS = (
  ...
  &#39;corsheaders&#39;,
  ...
)

...

MIDDLEWARE_CLASSES = (
  ...
  &#39;corsheaders.middleware.CorsMiddleware&#39;,
  &#39;django.middleware.common.CommonMiddleware&#39;,
  ...
)

可以配置允许跨域访问的白名单或者直接设置为允许所有的跨域访问，具体的配置可以看看他们的github页说明。

更多Python的Django应用程序解决AJAX跨域访问相关文章请关注PHP中文网！

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

How to solve the permissions problem encountered when viewing Python version in Linux terminal?Apr 01, 2025 pm 05:09 PM

Solution to permission issues when viewing Python version in Linux terminal When you try to view Python version in Linux terminal, enter python...

How Do I Use Beautiful Soup to Parse HTML?Mar 10, 2025 pm 06:54 PM

This article explains how to use Beautiful Soup, a Python library, to parse HTML. It details common methods like find(), find_all(), select(), and get_text() for data extraction, handling of diverse HTML structures and errors, and alternatives (Sel

Serialization and Deserialization of Python Objects: Part 1Mar 08, 2025 am 09:39 AM

Serialization and deserialization of Python objects are key aspects of any non-trivial program. If you save something to a Python file, you do object serialization and deserialization if you read the configuration file, or if you respond to an HTTP request. In a sense, serialization and deserialization are the most boring things in the world. Who cares about all these formats and protocols? You want to persist or stream some Python objects and retrieve them in full at a later time. This is a great way to see the world on a conceptual level. However, on a practical level, the serialization scheme, format or protocol you choose may determine the speed, security, freedom of maintenance status, and other aspects of the program

How to Perform Deep Learning with TensorFlow or PyTorch?Mar 10, 2025 pm 06:52 PM

This article compares TensorFlow and PyTorch for deep learning. It details the steps involved: data preparation, model building, training, evaluation, and deployment. Key differences between the frameworks, particularly regarding computational grap

Mathematical Modules in Python: StatisticsMar 09, 2025 am 11:40 AM

Python's statistics module provides powerful data statistical analysis capabilities to help us quickly understand the overall characteristics of data, such as biostatistics and business analysis. Instead of looking at data points one by one, just look at statistics such as mean or variance to discover trends and features in the original data that may be ignored, and compare large datasets more easily and effectively. This tutorial will explain how to calculate the mean and measure the degree of dispersion of the dataset. Unless otherwise stated, all functions in this module support the calculation of the mean() function instead of simply summing the average. Floating point numbers can also be used. import random import statistics from fracti

Scraping Webpages in Python With Beautiful Soup: Search and DOM ModificationMar 08, 2025 am 10:36 AM

This tutorial builds upon the previous introduction to Beautiful Soup, focusing on DOM manipulation beyond simple tree navigation. We'll explore efficient search methods and techniques for modifying HTML structure. One common DOM search method is ex

What are some popular Python libraries and their uses?Mar 21, 2025 pm 06:46 PM

The article discusses popular Python libraries like NumPy, Pandas, Matplotlib, Scikit-learn, TensorFlow, Django, Flask, and Requests, detailing their uses in scientific computing, data analysis, visualization, machine learning, web development, and H

How to Create Command-Line Interfaces (CLIs) with Python?Mar 10, 2025 pm 06:48 PM

This article guides Python developers on building command-line interfaces (CLIs). It details using libraries like typer, click, and argparse, emphasizing input/output handling, and promoting user-friendly design patterns for improved CLI usability.

See all articles