More Proxy Actions
In addition to the proxy actions described in Proxy Request URI Actions and Proxy Request Header Actions, OpenResty Edge also provides more proxy actions.
Enable Proxy Cache Revalidate
This action is used to enable: the revalidation of expired cached items using conditional requests with “If-Modified-Since” and “If-None-Match” header fields.
Use Stale Proxy Cache
This action is used to determine the circumstances under which stale cached responses can be used in communication with the proxy server. For example, when a 504 error occurs on a request, the old cache is used for the response.