- Author:
- David Nickerson <nickerso@users.sourceforge.net>
- Date:
- 2009-07-16 02:00:03+12:00
- Desc:
- the starting point for the HH tutorial example
- Permanent Source URI:
- https://models.fieldml.org/workspace/a1/rawfile/f6a8f90307388eb4b040ee3566b84d88b59247f7/dojo-presentation/js/dojo/dojox/storage/WhatWGStorageProvider.js
dojo.provide("dojox.storage.WhatWGStorageProvider");
dojo.require("dojox.storage.Provider");
dojo.require("dojox.storage.manager");
dojo.declare("dojox.storage.WhatWGStorageProvider", [ dojox.storage.Provider ], {
// summary:
// Storage provider that uses WHAT Working Group features in Firefox 2
// to achieve permanent storage.
// description:
// The WHAT WG storage API is documented at
// http://www.whatwg.org/specs/web-apps/current-work/#scs-client-side
//
// You can disable this storage provider with the following djConfig
// variable:
// var djConfig = { disableWhatWGStorage: true };
//
// Authors of this storage provider-
// JB Boisseau, jb.boisseau@eutech-ssii.com
// Brad Neuberg, bkn3@columbia.edu
initialized: false,
_domain: null,
_available: null,
_statusHandler: null,
_allNamespaces: null,
_storageEventListener: null,
initialize: function(){
if(dojo.config["disableWhatWGStorage"] == true){
return;
}
// get current domain
this._domain = this._getDomain();
// console.debug(this._domain);
// indicate that this storage provider is now loaded
this.initialized = true;
dojox.storage.manager.loaded();
},
isAvailable: function(){
try{
var myStorage = globalStorage[this._getDomain()];
}catch(e){
this._available = false;
return this._available;
}
this._available = true;
return this._available;
},
put: function(key, value, resultsHandler, namespace){
if(this.isValidKey(key) == false){
throw new Error("Invalid key given: " + key);
}
namespace = namespace||this.DEFAULT_NAMESPACE;
// get our full key name, which is namespace + key
key = this.getFullKey(key, namespace);
this._statusHandler = resultsHandler;
// serialize the value;
// handle strings differently so they have better performance
if(dojo.isString(value)){
value = "string:" + value;
}else{
value = dojo.toJson(value);
}
// register for successful storage events.
var storageListener = dojo.hitch(this, function(evt){
// remove any old storage event listener we might have added
// to the window on old put() requests; Firefox has a bug
// where it can occassionaly go into infinite loops calling
// our storage event listener over and over -- this is a
// workaround
// FIXME: Simplify this into a test case and submit it
// to Firefox
window.removeEventListener("storage", storageListener, false);
// indicate we succeeded
if(resultsHandler){
resultsHandler.call(null, this.SUCCESS, key, null, namespace);
}
});
window.addEventListener("storage", storageListener, false);
// try to store the value
try{
var myStorage = globalStorage[this._domain];
myStorage.setItem(key, value);
}catch(e){
// indicate we failed
this._statusHandler.call(null, this.FAILED, key, e.toString(), namespace);
}
},
get: function(key, namespace){
if(this.isValidKey(key) == false){
throw new Error("Invalid key given: " + key);
}
namespace = namespace||this.DEFAULT_NAMESPACE;
// get our full key name, which is namespace + key
key = this.getFullKey(key, namespace);
// sometimes, even if a key doesn't exist, Firefox
// will return a blank string instead of a null --
// this _might_ be due to having underscores in the
// keyname, but I am not sure.
// FIXME: Simplify this bug into a testcase and
// submit it to Firefox
var myStorage = globalStorage[this._domain];
var results = myStorage.getItem(key);
if(results == null || results == ""){
return null;
}
results = results.value;
// destringify the content back into a
// real JavaScript object;
// handle strings differently so they have better performance
if(dojo.isString(results) && (/^string:/.test(results))){
results = results.substring("string:".length);
}else{
results = dojo.fromJson(results);
}
return results;
},
getNamespaces: function(){
var results = [ this.DEFAULT_NAMESPACE ];
// simply enumerate through our array and save any string
// that starts with __
var found = {};
var myStorage = globalStorage[this._domain];
var tester = /^__([^_]*)_/;
for(var i = 0; i < myStorage.length; i++){
var currentKey = myStorage.key(i);
if(tester.test(currentKey) == true){
var currentNS = currentKey.match(tester)[1];
// have we seen this namespace before?
if(typeof found[currentNS] == "undefined"){
found[currentNS] = true;
results.push(currentNS);
}
}
}
return results;
},
getKeys: function(namespace){
namespace = namespace||this.DEFAULT_NAMESPACE;
if(this.isValidKey(namespace) == false){
throw new Error("Invalid namespace given: " + namespace);
}
// create a regular expression to test the beginning
// of our key names to see if they match our namespace;
// if it is the default namespace then test for the presence
// of no namespace for compatibility with older versions
// of dojox.storage
var namespaceTester;
if(namespace == this.DEFAULT_NAMESPACE){
namespaceTester = new RegExp("^([^_]{2}.*)$");
}else{
namespaceTester = new RegExp("^__" + namespace + "_(.*)$");
}
var myStorage = globalStorage[this._domain];
var keysArray = [];
for(var i = 0; i < myStorage.length; i++){
var currentKey = myStorage.key(i);
if(namespaceTester.test(currentKey) == true){
// strip off the namespace portion
currentKey = currentKey.match(namespaceTester)[1];
keysArray.push(currentKey);
}
}
return keysArray;
},
clear: function(namespace){
namespace = namespace||this.DEFAULT_NAMESPACE;
if(this.isValidKey(namespace) == false){
throw new Error("Invalid namespace given: " + namespace);
}
// create a regular expression to test the beginning
// of our key names to see if they match our namespace;
// if it is the default namespace then test for the presence
// of no namespace for compatibility with older versions
// of dojox.storage
var namespaceTester;
if(namespace == this.DEFAULT_NAMESPACE){
namespaceTester = new RegExp("^[^_]{2}");
}else{
namespaceTester = new RegExp("^__" + namespace + "_");
}
var myStorage = globalStorage[this._domain];
var keys = [];
for(var i = 0; i < myStorage.length; i++){
if(namespaceTester.test(myStorage.key(i)) == true){
keys[keys.length] = myStorage.key(i);
}
}
dojo.forEach(keys, dojo.hitch(myStorage, "removeItem"));
},
remove: function(key, namespace){
// get our full key name, which is namespace + key
key = this.getFullKey(key, namespace);
var myStorage = globalStorage[this._domain];
myStorage.removeItem(key);
},
isPermanent: function(){
return true;
},
getMaximumSize: function(){
return this.SIZE_NO_LIMIT;
},
hasSettingsUI: function(){
return false;
},
showSettingsUI: function(){
throw new Error(this.declaredClass + " does not support a storage settings user-interface");
},
hideSettingsUI: function(){
throw new Error(this.declaredClass + " does not support a storage settings user-interface");
},
getFullKey: function(key, namespace){
namespace = namespace||this.DEFAULT_NAMESPACE;
if(this.isValidKey(namespace) == false){
throw new Error("Invalid namespace given: " + namespace);
}
// don't append a namespace string for the default namespace,
// for compatibility with older versions of dojox.storage
if(namespace == this.DEFAULT_NAMESPACE){
return key;
}else{
return "__" + namespace + "_" + key;
}
},
_getDomain: function(){
// see: https://bugzilla.mozilla.org/show_bug.cgi?id=357323
return ((location.hostname == "localhost" && dojo.isFF && dojo.isFF < 3) ? "localhost.localdomain" : location.hostname);
}
});
dojox.storage.manager.register("dojox.storage.WhatWGStorageProvider",
new dojox.storage.WhatWGStorageProvider());
