Python 使用 Flask，如何修改所有输出的 Cache-Control 标头？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/23112316/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Using Flask, how do I modify the Cache-Control header for ALL output?
提问by wuxiekeji
I tried using this
我试过用这个
@app.after_request
def add_header(response):
response.headers['Cache-Control'] = 'max-age=300'
return response
But this causes a duplicate Cache-Control header to appear. I only want max-age=300, NOT the max-age=1209600 line!
但这会导致出现重复的 Cache-Control 标头。我只想要 max-age=300，而不是 max-age=1209600 行！
$ curl -I http://my.url.here/
HTTP/1.1 200 OK
Date: Wed, 16 Apr 2014 14:24:22 GMT
Server: Apache
Cache-Control: max-age=300
Content-Length: 107993
Cache-Control: max-age=1209600
Expires: Wed, 30 Apr 2014 14:24:22 GMT
Content-Type: text/html; charset=utf-8
采纳答案by Martijn Pieters
Use the response.cache_controlobject; this is a ResponseCacheControl()instanceletting you set various cache attributes directly. Moreover, it'll make sure not to add duplicate headers if there is one there already.
使用response.cache_control对象；这是一个让您直接设置各种缓存属性的ResponseCacheControl()实例。此外，如果已经有一个标题，它会确保不添加重复的标题。
@app.after_request
def add_header(response):
response.cache_control.max_age = 300
return response
回答by aldel
You can set the default value for all static fileswhen you create the Flask application:
您可以在创建 Flask 应用程序时为所有静态文件设置默认值：
app = Flask(__name__)
app.config['SEND_FILE_MAX_AGE_DEFAULT'] = 300
Note that if you modify request.cache_controlin after_request, as in the accepted answer, this will also modify the Cache-Controlheader for static files and may override the behavior you set as I showed above. I'm currently using the following code to completely disable caching for dynamically generated content but not static files:
请注意，如果您像在接受的答案中那样修改request.cache_controlin after_request，这也会修改Cache-Control静态文件的标头，并且可能会覆盖您设置的行为，如我上面所示。我目前正在使用以下代码完全禁用动态生成内容的缓存，而不是静态文件：
# No cacheing at all for API endpoints.
@app.after_request
def add_header(response):
# response.cache_control.no_store = True
if 'Cache-Control' not in response.headers:
response.headers['Cache-Control'] = 'no-store'
return response
Not completely sure this is the best way, but it's working for me so far.
不完全确定这是最好的方法，但到目前为止它对我有用。
