In case you're looking for a way to call lawnchair from angularJS, here's a handy service factory:
.factory("LawnchairFactory", function($window, $log, $parse) {
return function(name, config) {
var collection = {};
var array = [];
var isArray = config && config.isArray;
var idGetter = $parse((config && config.entryKey) ? config.entryKey : "id");
var transformSave = (config && config.transformSave) ? config.transformSave : angular.identity;
var transformLoad = (config && config.transformLoad) ? config.transformLoad : angular.identity;
function getEntryId(entry){
try {
return idGetter(entry);
} catch(e) {
return null;
}
}
function lawnchairBucket(callback) { return new Lawnchair({name:name}, callback); }
function saveEntry(data,key) {
key = key.toString();
if(angular.isObject(data) && data !== collection[key]){
collection[key] = collection[key] || {};
angular.extend(collection[key], data);
} else {
collection[key] = data;
}
var update = {key:key, value:transformSave(collection[key])};
try {
lawnchairBucket(function() { this.save(update); });
} catch(e) {
if (e.name === "QUOTA_EXCEEDED_ERR" || e.name === "NS_ERROR_DOM_QUOTA_REACHED") {
$window.localStorage.clear();
}
$log.info("LocalStorage Exception ==> " + e.message);
}
}
function updateArray(data){
array.length = 0;
_.each(data, function(o) { array.push(o); });
return array;
}
function updateCache(obj,key) {
if(obj && angular.isObject(obj) && collection[key] && collection[key] !== obj){
angular.extend(collection[key], obj);
} else {
collection[key] = obj;
}
}
function updateCacheFromStorage(cache, storage) {
if(storage){
if(angular.isObject(storage.value) && angular.isObject(cache)) {
angular.extend(cache, transformLoad(storage.value));
} else {
cache = transformLoad(storage.value);
}
updateCache(cache, storage.key);
}
return cache;
}
function allAsCollection(callback){
lawnchairBucket(function() {
this.all(function(result) {
angular.forEach(result, function(o) { updateCache(o.value, o.key); });
if(callback){
callback(collection);
}
});
});
return collection;
}
function allAsArray(callback){
return updateArray(allAsCollection(function(data){
updateArray(data);
if(callback){
callback(array);
}
}));
}
function removeEntry(key) {
delete collection[key];
lawnchairBucket(function() { this.remove(key); });
}
function getDefault(key) {
if(collection[key]) {
return collection[key];
} else {
var d = {};
idGetter.assign(d,key);
return d;
}
}
var lawnchair = {
collection: collection,
save: function(data, key, clear) {
if(!data){
data = collection; // if nothing is set save the current cache
key = null;
}
if (angular.isArray(data)) {
angular.forEach(data, function(e, index) { saveEntry(e, getEntryId(e) || index); }); // Save a Array
} else if(key || (data && getEntryId(data))) {
saveEntry(data, key || getEntryId(data)); // save one entry
} else {
angular.forEach(data, saveEntry); // save a collection
}
if(clear) {
var newIds = angular.isArray(data) ? _.chain(data).map(getEntryId).map(String).value() : _.keys(data);
_.chain(collection).keys().difference(newIds).each(removeEntry);
// remove entries wihtout ids
_.chain(collection).filter(function(entry){ return !getEntryId(entry); }).keys().each(removeEntry);
}
if(isArray){
updateArray(collection);
}
},
batch: function(keys, target, callback) {
var cache = _.chain(keys).map(function(k){ return getDefault(k);}).value();
if(target && angular.isArray(target)){
target.length = 0;
_.each(cache, function(o) { target.push(o); });
} else {
target = cache;
}
lawnchairBucket(function() {
this.get(keys, function(result) {
if(result){
for(var i = result.length - 1; i >= 0; i--){
target[i] = updateCacheFromStorage(target[i], result[i]);
}
}
if(callback){
callback(target);
}
});
});
return target;
},
get: function(key, callback) {
var value = getDefault(key);
lawnchairBucket(function() {
this.get(key, function(result) {
if(result){
value = updateCacheFromStorage(value, result);
}
if(callback){
callback(value);
}
});
});
return value;
},
all: isArray ? allAsArray : allAsCollection,
remove: removeEntry,
nuke: function() {
lawnchairBucket(function() { this.nuke(); });
},
destroy: function() {
for (var key in collection){
delete collection[key];
}
lawnchairBucket(function() { this.nuke(); });
}
};
return lawnchair;
};
})
