Commit 8638c1a0 authored by Colm MacCarthaigh's avatar Colm MacCarthaigh
Browse files 

Improve the cache hit/miss ratio by canonicalising the url key. hostname's
are matched case-insensitively, port-based vhosts are catered for and the
scheme included for future multi-scheme caching compatibility.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@239407 13f79535-47bb-0310-9956-ffa450edef68
parent 9fc07d5f

modules/cache/cache_storage.c

+74 −4
Original line number Diff line number Diff line
@@ -320,12 +320,82 @@ int cache_select_url(request_rec *r, char *url) 
apr_status_t cache_generate_key_default(request_rec *r, apr_pool_t* p,

                                        char**key)

{

    if (r->hostname) {

        *key = apr_pstrcat(p, r->hostname, r->uri, "?", r->args, NULL);

    char *port_str, *scheme, *hn;

    const char * hostname;

    int i;



    /* Use the canonical name to improve cache hit rate, but only if this is

     * not a proxy request. 

     */ 

    if (!r->proxyreq) {

        /* Use _default_ as the hostname if none present, as in mod_vhost */

        hostname =  ap_get_server_name(r);

        if (!hostname) {

            hostname = "_default_";

        }

    }

    else if(r->parsed_uri.hostname) {

        /* Copy the parsed uri hostname */

        hn = apr_pcalloc(p, strlen(r->parsed_uri.hostname) + 1);

        for (i = 0; r->parsed_uri.hostname[i]; i++) {

            hn[i] = apr_tolower(r->parsed_uri.hostname[i]);

        }

        /* const work-around */

        hostname = hn;

    }

    else {

        *key = apr_pstrcat(p, r->uri, "?", r->args, NULL);

        /* We are a proxied request, with no hostname. Unlikely

         * to get very far - but just in case */

        hostname = "_default_";

    }

    return APR_SUCCESS;



    /* Copy the scheme, ensuring that it is lower case. If the parsed uri

     * contains no string or if this is not a proxy request.

     */

    if (r->proxyreq && r->parsed_uri.scheme) {

        /* Copy the scheme */

        scheme = apr_pcalloc(p, strlen(r->parsed_uri.scheme) + 1);

        for (i = 0; r->parsed_uri.scheme[i]; i++) {

            scheme[i] = apr_tolower(r->parsed_uri.scheme[i]);

        }

    }

    else {

        scheme = "http";

    }



    /* If the content is locally generated, use the port-number of the

     * current server. Otherwise. copy the URI's port-string (which may be a

     * service name). If the URI contains no port-string, use apr-util's

     * notion of the default port for that scheme - if available.

     */

    if(r->proxyreq) {

        if (r->parsed_uri.port_str) {

            port_str = apr_pcalloc(p, strlen(r->parsed_uri.port_str) + 2);

            port_str[0] = ':';

            for (i = 0; r->parsed_uri.port_str[i]; i++) {

                port_str[i + 1] = apr_tolower(r->parsed_uri.port_str[i]);

            }

        }

        else if (apr_uri_port_of_scheme(scheme)) {

            port_str = apr_psprintf(p, ":%u", apr_uri_port_of_scheme(scheme));

        }

        else {

            /* No port string given in the AbsoluteUri, and we have no

             * idea what the default port for the scheme is. Leave it

             * blank and live with the inefficiency of some extra cached

             * entities.

             */

            port_str = "";

        }       

    }       

    else {

        /* Use the server port */

        port_str = apr_psprintf(p, ":%u", ap_get_server_port(r));

    }



    /* Key format is a URI */

    *key = apr_pstrcat(p, scheme, "://", hostname, port_str,

                       r->parsed_uri.path, "?", r->args, NULL);



    return APR_SUCCESS;

}