I want to using proxy_cache in front of internal location,but proxy_pass not work.my code like following:

location /proxy {
proxy_cache cache;
proxy_cache_key $uri;
proxy_cache_valid 200 304 10d;
expires 10d;
proxy_pass @bar;
}

location @bar {
internal;
content_by_lua '
ngx.log(ngx.ERR,"sssssssssssssssssss")
ngx.say("yaha")
';
}

proxy_cache must used with proxy_pass?any other method to do this?

Thanks.