Django1.8跨域问题解决

1. 问题描述

出现错误：Access to XMLHttpRequest at 'http://xxx.xxx.xxx.xxx:8000/testjson' from origin 'null' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

原因： Django框架中默认没有允许跨域请求！

2.  解决

在环境中安装 django-cors-headers插件！   注意版本要对应，否则不兼容，这里使用的是Django1.8 + django-cors-headers2.0

pip install django-cors-headers==2.0

然后在Django项目配置文件（settings.py）中加入如下代码：

# 应用注册部分
INSTALLED_APPS = (
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    # 允许跨域
    'corsheaders',
    'booktest',    # 注册应用
)

中间件部分

MIDDLEWARE_CLASSES = (
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',

    # 允许跨域
    'corsheaders.middleware.CorsMiddleware',
    'django.middleware.common.CommonMiddleware',  # 注意顺序

    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
    'django.middleware.security.SecurityMiddleware',

)

在文档最后添加：

# 允许跨域
# 跨域增加忽略
CORS_ALLOW_CREDENTIALS = True
CORS_ORIGIN_ALLOW_ALL = True
CORS_ORIGIN_WHITELIST = (
     '*',  # 请求的域名
)
CORS_ALLOW_METHODS = (
    'DELETE',
    'GET',
    'OPTIONS',
    'PATCH',
    'POST',
    'PUT',
    'VIEW',
)
CORS_ALLOW_HEADERS = (
    'XMLHttpRequest',
    'X_FILENAME',
    'accept-encoding',
    'authorization',
    'content-type',
    'dnt',
    'origin',
    'user-agent',
    'x-csrftoken',
    'x-requested-with',
)

# 部署到云服务上必备
ALLOWED_HOSTS = ['*']

3. 效果