如何在Flask中禁用缓存？

Question

我有一些缓存问题。

我正在运行一个很小的Web应用程序，该应用程序读取一帧并将其保存到磁盘，然后在浏览器窗口中显示。

我知道，这可能不是最好的解决方案，但是每次我以相同的名称保存此读取帧时，浏览器都会对其进行缓存。

我尝试使用html元标记，但没有成功：

<meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate" />
<meta http-equiv="Pragma" content="no-cache" />
<meta http-equiv="Expires" content="0" />

另外，我已经尝试过这一步骤（特定于flask）：

resp.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
resp.headers["Pragma"] = "no-cache"
resp.headers["Expires"] = "0"

这是我尝试修改 resp 标头的方式：

r = make_response(render_template('video.html', video_info=video_info))

r.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
r.headers["Pragma"] = "no-cache"
r.headers["Expires"] = "0"

仍然在Google Chrome和Safari中进行缓存。 这里可能是什么问题？

Answer 1

OK,

finally it worked with this:

@app.after_request
def add_header(r):
    """
    Add headers to both force latest IE rendering engine or Chrome Frame,
    and also to cache the rendered page for 10 minutes.
    """
    r.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
    r.headers["Pragma"] = "no-cache"
    r.headers["Expires"] = "0"
    r.headers['Cache-Control'] = 'public, max-age=0'
    return r

If you add this, this function will called after each request done. Please,see here

I would be happy, if anyone could explain me why this headers overwriting did not work from the page handler?

Thank you.