如何使用Flask-Restless启用CORS

Posted 2021-04-19

我有一个使用Flask-Restless创建的postgres数据库的API，并使用Apache提供服务。

在我收到多个似乎与OPTIONS请求密切相关的“CORS Error Access-Control-Allow-Origin”标头时，API会一直运行，直到我尝试使用基于javascript的前端来访问API。

我尝试了以下修复程序

[1.在阿帕奇的可用角色] [1]

 <VirtualHost *:80>
            Header add Access-Control-Allow-Origin "*"
            Header add Access-Control-Allow-Headers "origin, x-requested-with, content-type, Authorization"
            Header add Access-Control-Allow-Methods "PUT, GET, POST, DELETE, OPTIONS"
            ServerName localhost
            WSGIScriptAlias / /home/drmclean/bboxx/git/Smart-Solar-Server/SmartSolarServer.wsgi
            WSGIScriptReloading On

            <Directory /home/drmclean/bboxx/git/Smart-Solar-Server/>
                    Header add Access-Control-Allow-Origin "*"
                    Header add Access-Control-Allow-Headers "origin, x-requested-with, content-type, Authorization"
                    Header add Access-Control-Allow-Methods "PUT, GET, POST, DELETE, OPTIONS"
                    Require all granted
                    Order allow,deny
                    Allow from all
            </Directory>

            Alias /docs /home/drmclean/bboxx/git/Smart-Solar-Server/swagger
            <Directory /home/drmclean/bboxx/git/Smart-Solar-Server/swagger/>
                    Header add Access-Control-Allow-Origin "*"
                    Header add Access-Control-Allow-Headers "origin, x-requested-with, content-type, Authorization"
                    Header add Access-Control-Allow-Methods "PUT, GET, POST, DELETE, OPTIONS"
                    Require all granted
                    Header set Access-Control-Allow-Origin "*"
                    Order allow,deny
                    Allow from all
            </Directory>
            ErrorLog ${APACHE_LOG_DIR}/error.log
            LogLevel warn
            CustomLog ${APACHE_LOG_DIR}/access.log combined
            <IfModule mod_rewrite.c>
                    RewriteEngine on
                    # Pass Authorization headers to an environment variable
                    RewriteCond %{HTTP:Authorization} ^(.*)
                    RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
            </IfModule>

2.Enable CORS using the flask-cors extension

app = Flask(__name__, static_folder= paths.base_path+'/swagger/')
cors = CORS(app)

3.使用烧瓶 - 不安全使用CORS

def allow_control_headers(response):
response.headers['Access-Control-Allow-Origin'] = '*'
response.headers['Access-Control-Allow-Credentials'] = 'true'
return response

bp = manager.create_api(REDACTED)
bp.after_request(allow_control_headers)

毋庸置疑，到目前为止还没有任何工作。

1. 不删除CORS警告。
2. 似乎删除了某些端点但不是其他端点的CORS错误，将其更改为cors = CORS（app，response = r“/ v1 / *”）带回了最初删除的CORS错误。
3. 抛出语法错误为“bp没有属性after_request”，尽管我直接从文档中复制了语法。 （here）

谁能解释一下，

1. 为什么上述修复程序没有删除CORS问题。
2. 如何解决我的问题并有效地启用Cross-Origin-Resource-SHaring？

答案

选项3最接近，但您引用的文档仅适用于特定版本的Flask Restless，而不是最新版本。我建议将Flask's after_this_request processor与Flask Restless的预处理器结合使用

def allow_control_headers(**kw):

    @after_this_request
    def add_headers(response):
        response.headers['Access-Control-Allow-Origin'] = '*'
        response.headers['Access-Control-Allow-Credentials'] = 'true'
        return response

bp = manager.create_api({
  ...
  'preprocessors: {'GET_SINGLE': [allow_control_headers]}
  ...
})