解决Django cors跨域问题

# 1、安装第三方库 django-cors-headers
# 2、在settings.py中添加"corsheaders.middleware.CorsMiddleware",在SessionMiddleware和CommonMiddleware的中间
# 3、在INSTALLED_APPS里添加“corsheaders”
INSTALLED_APPS = [
    "search.apps.SearchConfig",
    "data.apps.DataConfig",
    "record_data.apps.RecordDataConfig",
    "deleted_data.apps.DeletedDataConfig",
    "mgmt.apps.MgmtConfig",
    "c_test.apps.CTestConfig",
    "rest_framework",
    "django.contrib.admin",
    "django.contrib.auth",
    "django.contrib.contenttypes",
    "django.contrib.sessions",
    "django.contrib.messages",
    "django.contrib.staticfiles",
    "corsheaders",  # 新增
]
# 4、在中间件中添加corsheaders.middleware.CorsMiddleware,django.middleware.common.CommonMiddleware
MIDDLEWARE = [
    # "utils.middleware.ExceptionMiddleware",
    "django.middleware.security.SecurityMiddleware",
    "django.contrib.sessions.middleware.SessionMiddleware",
    "corsheaders.middleware.CorsMiddleware",  # 新增/必须在common中间件上面
    "django.middleware.common.CommonMiddleware",
    # "django.middleware.csrf.CsrfViewMiddleware",
    "django.contrib.auth.middleware.AuthenticationMiddleware",
    "django.contrib.messages.middleware.MessageMiddleware",
    "django.middleware.clickjacking.XFrameOptionsMiddleware",
]
# 5、在settings.py底部增加
CORS_ALLOW_CREDENTIALS = True  # 允许携带cookie
CORS_ORIGIN_ALLOW_ALL = True  # 放行所有
CORS_ORIGIN_WHITELIST = ("*")  # 白名单
# CORS_ALLOW_METHODS：字符串列表，允许用哪些HTTP请求方法。
CORS_ALLOW_METHODS = (
    "DELETE",
    "GET",
    "OPTIONS",
    "PATCH",
    "POST",
    "PUT",
    "VIEW",
)
# CORS_ALLOW_HEADERS：字符串列表，允许使用哪些非标准HTTP请求头。
CORS_ALLOW_HEADERS = (
    "accept",
    "accept-encoding",
    "authorization",
    "content-type",
    "dnt",
    "origin",
    "user-agent",
    "x-csrftoken",
    "x-requested-with",
)

# 可以自己注册一个中间件，在中间件process_response方法中对response进行封装
def process_response(self, request, response):
    response["Content-Type"] = "application/json"  # 响应信息的内容格式
    response["Access-Control-Allow-Origin"] = "*"  # 允许跨域请求的源地址， * 表示：允许所有地址
    response["Access-Control-Allow-Methods"] = "POST, GET, OPTIONS"  # 允许跨域请求的具体方法
    response["Access-Control-Max-Age"] = "1000"  # 用来指定本次预检请求的有效期，单位为秒，，在此期间不用发出另一条预检请求。
    response["Access-Control-Allow-Headers"] = "*"
    return response