///
///
///
//TODO: handle running out of space
//TODO: migrate from Squirrel to web sql where we can a) store more content, b) have more control
_b.ClientCache = {
// Instantiate a new Squirrel cache
_cache: new Squirrel("bondi", 3600 * 24 * 365),
/*______________________________________________________________________________________________________________________________________________________________________________________*/
clearSubCache: function (subCache) {
///Clears a specific subCache, by name.
///Name of sub cache, required
///true/false indicating success
return !!subCache && this._cache.clear(subCache);
},
/*______________________________________________________________________________________________________________________________________________________________________________________*/
cacheObject: function (subCache, key, jsonObject) {
/// Caches a json object
/// Name of sub cache to use
/// The cache key
/// The object to cache in json notation
///true/false indicating success
var stringData = JSON.stringify(jsonObject), result;
try {
result = this._cache.write(subCache, key, stringData);
}
catch (exc) {
//handle apparent iPad 3.2 bug in which the cached item must be removed prior to insert
if (exc.name === "QUOTA_EXCEEDED_ERR") {
try {
this._cache.remove(subCache, key);
result = this._cache.write(subCache, key, stringData);
if (!result) {
debug.log("Secondary cache attempt failed");
}
}
catch (exc2) {
debug.error("Secondary cache attempt error: " + exc2.name);
result = false;
}
} else {
result = false;
}
}
return !!result;
},
/*______________________________________________________________________________________________________________________________________________________________________________________*/
getCachedObject: function (subCache, key) {
/// Caches a json object
/// Name of sub cache to use
/// The cache key
///The cached object in json notation
var data;
try {
data = this._cache.read(subCache, key);
data = JSON.parse(data);
}
catch (e) { }
return data;
},
/*______________________________________________________________________________________________________________________________________________________________________________________*/
getThenCache: function (subCache, url, type, success, error) {
///
/// Loads content from the server using an HTTP GET request, then caches the content in localStorage.
///
/// Name of sub cache to use
/// The URL of the content to load - also used as cache key.
/// Type of data to be returned to callback function. Valid values are html, json, text
/// Success callback: function(data, status, xhr).
/// Error callback: function(xhr, status, error).
var doCache = _b.Core.useCache
var stringData = "";
//first clear out what was there
this._cache.remove(subCache, url);
//then execute a jQuery Ajax Get
jQuery.ajax({
type: "GET",
url: url,
success: function (data, status, xhr) {
//convert data to a string, if needed
try {
switch (type) {
case "json":
stringData = JSON.stringify(data);
break;
case "xml":
stringData = (new XMLSerializer()).serializeToString(data);
break;
default:
stringData = data.toString();
}
}
catch (e) { doCache = false; };
//cache the stringified data in the subCache, set status if not successful, then callback with the original data
status = (doCache && _b.ClientCache._cache.write(subCache, url, stringData)) ? status : "NOTCACHED";
success(data, status, xhr);
},
error: error,
dataType: type
});
},
/*______________________________________________________________________________________________________________________________________________________________________________________*/
cachedGet: function (subCache, url, type, forceRefresh, success, error) {
///
/// Loads content from the cache or the server using an HTTP GET request.
///
/// Name of sub cache to use
/// The URL of the content to load - also used as cache key.
/// Type of data to be returned to callback function. Valid values are html, json, text.
/// Whether to force a refresh from the server.
/// Success callback: function(data, status, xhr).
/// Error callback: function(xhr, status, error).
var cachedData = this._cache.read(subCache, url);
if (!forceRefresh && cachedData && _b.Core.useCache) {
success(cachedData, "FROMCACHE");
} else {
this.getThenCache(subCache, url, type, success, error);
}
},
/*______________________________________________________________________________________________________________________________________________________________________________________*/
cachedGetJSON: function (subCache, url, forceRefresh, success, error) {
///
/// Loads parsed JSON from the cache or from the server using an HTTP GET request.
///
/// Name of sub cache to use
/// The URL of the content to load - also used as cache key.
/// Whether to force a refresh from the server.
/// Success callback: function(jsonData, status, xhr).
/// Error callback: function(xhr, status, error).
this.cachedGet(subCache, url, "json", forceRefresh,
function (data, status, xhr) {
if (status === "FROMCACHE" && JSON) {
try { data = JSON.parse(data); }
catch (e) { }
}
success(data, status, xhr);
},
error);
},
/*______________________________________________________________________________________________________________________________________________________________________________________*/
cachedGetHtml: function (subCache, url, forceRefresh, success, error) {
///
/// Loads html content from the cache or the server using an HTTP GET request.
///
/// Name of sub cache to use
/// The URL of the content to load - also used as cache key.
/// Whether to force a refresh from the server.
/// Success callback: function(htmlData, status, xhr).
/// Error callback: function(xhr, status, error).
this.cachedGet(subCache, url, "html", forceRefresh, success, error);
}
};