If one has the pre-generated response for a "simple" `GET` request (one that doesn't use conditional headers, ranges, or other advanced HTTP features), then a s

If one has the pre-generated response for a "simple" `GET` request (one that doesn't use conditional headers, ranges, or other advanced HTTP features), then a server could easily generate proper responses (based on that simple response) to any such complex requests. For example: * `HEAD` is just taking the `GET` response and replying with just the headers (no body); * if the pre-generated `GET` response contains an `ETag` header, then the server could easily handle an `If-Match` and `If-None-Match`; (else, such a static server implementation could fallback for each resource with a temporary generated `ETag` that is obtained by hashing the path of the resource and some random token generated when the server was started;) * if the pre-generated `GET` response contains a `Last-Modified` header, then the server could easily handle `If-Modifiend-Since` and other related conditional requests; (else, the server could just consider that all resources have the `Last-Modified` header equal to the moment the server was started;) * if the client requests a range of that resource, the server could easily respond with a slice of the stored `GET` response; In fact, what I describe here is nothing out of the ordinary, all caching proxies do exactly this: they store the "simple" `GET` response, and then they derive all other responses based on that.