dr_cache_refresh

The dr_cache_refresh function provides a way of refreshing a cache entry when the plug-in requires it. This can be achieved by passing NULL for the ref parameter in dr_cache_init and by passing DR_CHECK in a dr_net_write call. If DR_CHECK is passed to dr_net_write and it returns with DR_EXPIR, the plug-in should generate new content in the entry and call dr_cache_refresh with that entry before calling dr_net_write again to send the response.

The plug-in may simply decide to replace the cached entry even if it has not expired (based on some other business logic). The dr_cache_refresh function is useful in this case. This way the plug-in does the cache refresh management actively by itself.

Syntax

PRInt32 dr_cache_refresh(DrHdl hdl, const char *key, PRUint32 klen,
PRIntervalTime timeout, Entry *entry, Request *rq, Session *sn);

Returns

1 if successful.

0 if an error occurs.

Parameters

The following table describes parameters for the dr_cache_refresh function.

Example

Entry entry;
char *key = "MOVIES"
GenNewMovieList(&entry.data, &entry.dataLen);  // Implemented by
                                               // plugin developer
if(!dr_cache_refresh(hdl, key, strlen(key), 0, &entry, rq, sn))
{
    ereport(LOG_FAILURE, "dr_cache_refresh() failed");
    return REQ_ABORTED;
}