- Use timestamp to give cached dataFetch data a lifetime, currently 29 seconds.

- Add another callback for cache registration, called whenever the cache is used.
This commit is contained in:
Nathan Gray 2014-08-04 17:04:11 +00:00
parent 671fec00d4
commit f361373455

View File

@ -24,6 +24,17 @@ egw.extend("data", egw.MODULE_APP_LOCAL, function (_app, _wnd) {
*/
var KNOWN_UID_LIMIT = 200;
/**
* Cache lifetime
*
* If cached results are used, we check their timestamp. If the timestamp
* is older than this, we will also ask for fresh data. For cached data
* younger than this, we only return the cache
*
* 29 seconds, 1 less then the fastest nextmatch autorefresh option
*/
var CACHE_LIFETIME = 29; // seconds
var lastModification = null;
/**
@ -161,7 +172,7 @@ egw.extend("data", egw.MODULE_APP_LOCAL, function (_app, _wnd) {
}
// Check to see if we need long-term caching of the query and its results
if(window.localStorage && _context.prefix && cacheCallback[_context.prefix])
if(window.localStorage && _context.prefix && cacheCallback[_context.prefix] && !_context.no_cache)
{
// Ask registered callbacks if we should cache this
for(var i = 0; i < cacheCallback[_context.prefix].length; i++)
@ -318,10 +329,39 @@ egw.extend("data", egw.MODULE_APP_LOCAL, function (_app, _wnd) {
var cached = window.localStorage.getItem(cache_key);
if(cached)
{
egw.debug('log', 'Data cached query: ' + cache_key + "\nprocessing...");
// Call right away with cached data. We'll still ask the server
// though.
parseServerResponse(JSON.parse(cached), _callback, _context);
cached = JSON.parse(cached);
var needs_update = true;
// Check timestamp
if(cached.lastModification && ((Date.now()/1000) - cached.lastModification) < CACHE_LIFETIME)
{
needs_update = false;
}
egw.debug('log', 'Data cached query from ' + new Date(cached.lastModification*1000)+': ' + cache_key + '('+
(needs_update ? 'will be' : 'will not be')+" updated)\nprocessing...");
// Call right away with cached data, but set no_cache flag
// to avoid re-caching this data with a new timestamp.
// We may still ask the server though.
var no_cache = _context.no_cache;
_context.no_cache = true;
parseServerResponse(cached, _callback, _context);
_context.no_cache = no_cache;
// If cache registrant wants notification of cache useage,
// let it know
if(cc.notification)
{
cc.notification.call(cc.context, needs_update);
}
if(!needs_update)
{
// Cached data is new enough, skip the server call
return;
}
}
}
}
@ -356,20 +396,25 @@ egw.extend("data", egw.MODULE_APP_LOCAL, function (_app, _wnd) {
*
* @param {string} prefix UID / Application prefix should match the
* individual record prefix
* @param {function} callback A function that will analize the provided fetch
* @param {function} callback_function A function that will analize the provided fetch
* parameters and return a reproducable cache key, or false to not cache
* the request.
* @param {function} notice_function A function that will be called whenever
* cached data is used. It is passed one parameter, a boolean that indicates
* if the server is or will be queried to refresh the cache. Do not fetch additional data
* inside this callback, and return quickly.
* @param {object} context Context for callback function.
*/
dataCacheRegister: function(prefix, callback, context)
dataCacheRegister: function(prefix, callback_function, notice_function, context)
{
if(typeof cacheCallback[prefix] == 'undefined')
{
cacheCallback[prefix] = [];
}
cacheCallback[prefix].push({
callback: callback,
context: context
callback: callback_function,
notification: notice_function || false,
context: context || null
});
},