Allows JSON data to be persisted easily by user scripts
This script should not be not be installed directly. It is a library for other scripts to include with the meta directive // @require https://update.greasyfork.org/scripts/10443/56962/DataCache%20-%20Simple%20storage%20wrapper.js
function DataCache(key) {
this._key = key;
this._data = {};
this.load();
}
DataCache.prototype = {
getValue: function(k) {
return this._data[k];
},
setValue: function(k, v) {
this._data[k] = v;
this.save();
},
deleteValue: function(k) {
if (k in this._data) {
delete this._data[k];
this.save();
}
},
hasValue: function(k) {
return k in this._data;
},
listValues: function() {
return Object.keys(this._data).sort();
},
clear: function() {
this._data = {};
this.save();
},
save: function() {
var s = JSON.stringify(this._data);
GM_setValue(this._key, s);
console.info('Cache(' + this._key + ') saved: ' + s);
},
load: function(s) {
try {
this._data = JSON.parse(s || GM_getValue(this._key));
}
catch (ex) {
this.clear();
}
},
edit: function() {
var res = window.prompt('Edit cached package URLs', JSON.stringify(this._data, null, 2));
if (res !== null) {
try {
this._data = res ? JSON.parse(res) : {};
this.save();
}
catch (ex) {
console.warn('Failed to update cache data: %s %o', ex.toString(), ex);
}
}
},
toString: function() {
return 'Cache(' + this._key + '): [' + this.listValues.join('\n') + ']';
},
dump: function() {
console.log('Cache(' + this._key + '):\n' + JSON.stringify(this._data, null, 2));
}
};