help request: how to use proxy-cache when response body size is zero

[qiufengfeng]

Description

The problems I encountered when using the proxy-cache plugin. How to avoid caching 0 byte files on apisix. when the body is empty, i think it can not be cached.

proxy-cache plugin has no_cache property，i have try set var on header_filter or body_filter stage , but they all not work.

Environment

• APISIX version (run apisix version):
• Operating system (run uname -a):
• OpenResty / Nginx version (run openresty -V or nginx -V):
• etcd version, if relevant (run curl http://127.0.0.1:9090/v1/server_info):
• APISIX Dashboard version, if relevant:
• Plugin runner version, for issues related to plugin runners:
• LuaRocks version, for installation issues (run luarocks --version):