source: [view]
define("dojox/data/OpmlStore", ["dojo", "dojox", "dojo/data/util/simpleFetch", "dojo/data/util/filter"], function(dojo, dojox) {
dojo.declare("dojox.data.OpmlStore", null, {
/* summary:
* The OpmlStore implements the dojo.data.api.Read API.
*/
/* examples:
* var opmlStore = new dojo.data.OpmlStore({url:"geography.xml"});
* var opmlStore = new dojo.data.OpmlStore({url:"http://example.com/geography.xml"});
*/
constructor: function(/* Object */ keywordParameters){
// summary: constructor
// keywordParameters: {url: String, label: String} Where label is optional and configures what should be used as the return from getLabel()
this._xmlData = null;
this._arrayOfTopLevelItems = [];
this._arrayOfAllItems = [];
this._metadataNodes = null;
this._loadFinished = false;
this.url = keywordParameters.url;
this._opmlData = keywordParameters.data; // XML DOM Document
if(keywordParameters.label){
this.label = keywordParameters.label;
}
this._loadInProgress = false; //Got to track the initial load to prevent duelling loads of the dataset.
this._queuedFetches = [];
this._identityMap = {};
this._identCount = 0;
this._idProp = "_I";
if(keywordParameters && "urlPreventCache" in keywordParameters){
this.urlPreventCache = keywordParameters.urlPreventCache?true:false;
}
},
// label: [public] string
// The attribute of the Opml item to act as a label.
label: "text",
// url: [public] string
// The location from which to fetch the Opml document.
url: "",
// urlPreventCache: [public] boolean
// Flag to denote if the underlying xhrGet call should set preventCache.
urlPreventCache: false,
_assertIsItem: function(/* item */ item){
if(!this.isItem(item)){
throw new Error("dojo.data.OpmlStore: a function was passed an item argument that was not an item");
}
},
_assertIsAttribute: function(/* item || String */ attribute){
// summary:
// This function tests whether the item passed in is indeed a valid 'attribute' like type for the store.
// attribute:
// The attribute to test for being contained by the store.
if(!dojo.isString(attribute)){
throw new Error("dojox.data.OpmlStore: a function was passed an attribute argument that was not an attribute object nor an attribute name string");
}
},
_removeChildNodesThatAreNotElementNodes: function(/* node */ node, /* boolean */ recursive){
var childNodes = node.childNodes;
if(childNodes.length === 0){
return;
}
var nodesToRemove = [];
var i, childNode;
for(i = 0; i < childNodes.length; ++i){
childNode = childNodes[i];
if(childNode.nodeType != 1){
nodesToRemove.push(childNode);
}
}
for(i = 0; i < nodesToRemove.length; ++i){
childNode = nodesToRemove[i];
node.removeChild(childNode);
}
if(recursive){
for(i = 0; i < childNodes.length; ++i){
childNode = childNodes[i];
this._removeChildNodesThatAreNotElementNodes(childNode, recursive);
}
}
},
_processRawXmlTree: function(/* xmlDoc */ rawXmlTree){
this._loadFinished = true;
this._xmlData = rawXmlTree;
var headNodes = rawXmlTree.getElementsByTagName('head');
var headNode = headNodes[0];
if(headNode){
this._removeChildNodesThatAreNotElementNodes(headNode);
this._metadataNodes = headNode.childNodes;
}
var bodyNodes = rawXmlTree.getElementsByTagName('body');
var bodyNode = bodyNodes[0];
if(bodyNode){
this._removeChildNodesThatAreNotElementNodes(bodyNode, true);
var bodyChildNodes = bodyNodes[0].childNodes;
for(var i = 0; i < bodyChildNodes.length; ++i){
var node = bodyChildNodes[i];
if(node.tagName == 'outline'){
this._identityMap[this._identCount] = node;
this._identCount++;
this._arrayOfTopLevelItems.push(node);
this._arrayOfAllItems.push(node);
this._checkChildNodes(node);
}
}
}
},
_checkChildNodes: function(node /*Node*/){
// summary:
// Internal function to recurse over all child nodes from the store and add them
// As non-toplevel items
// description:
// Internal function to recurse over all child nodes from the store and add them
// As non-toplevel items
//
// node:
// The child node to walk.
if(node.firstChild){
for(var i = 0; i < node.childNodes.length; i++){
var child = node.childNodes[i];
if(child.tagName == 'outline'){
this._identityMap[this._identCount] = child;
this._identCount++;
this._arrayOfAllItems.push(child);
this._checkChildNodes(child);
}
}
}
},
_getItemsArray: function(/*object?*/queryOptions){
// summary:
// Internal function to determine which list of items to search over.
// queryOptions: The query options parameter, if any.
if(queryOptions && queryOptions.deep){
return this._arrayOfAllItems;
}
return this._arrayOfTopLevelItems;
},
/***************************************
dojo.data.api.Read API
***************************************/
getValue: function( /* item */ item,
/* attribute || attribute-name-string */ attribute,
/* value? */ defaultValue){
// summary:
// See dojo.data.api.Read.getValue()
this._assertIsItem(item);
this._assertIsAttribute(attribute);
if(attribute == 'children'){
return (item.firstChild || defaultValue); //Object
}else{
var value = item.getAttribute(attribute);
return (value !== undefined) ? value : defaultValue; //Object
}
},
getValues: function(/* item */ item,
/* attribute || attribute-name-string */ attribute){
// summary:
// See dojo.data.api.Read.getValues()
this._assertIsItem(item);
this._assertIsAttribute(attribute);
var array = [];
if(attribute == 'children'){
for(var i = 0; i < item.childNodes.length; ++i){
array.push(item.childNodes[i]);
}
} else if(item.getAttribute(attribute) !== null){
array.push(item.getAttribute(attribute));
}
return array; // Array
},
getAttributes: function(/* item */ item){
// summary:
// See dojo.data.api.Read.getAttributes()
this._assertIsItem(item);
var attributes = [];
var xmlNode = item;
var xmlAttributes = xmlNode.attributes;
for(var i = 0; i < xmlAttributes.length; ++i){
var xmlAttribute = xmlAttributes.item(i);
attributes.push(xmlAttribute.nodeName);
}
if(xmlNode.childNodes.length > 0){
attributes.push('children');
}
return attributes; //Array
},
hasAttribute: function( /* item */ item,
/* attribute || attribute-name-string */ attribute){
// summary:
// See dojo.data.api.Read.hasAttribute()
return (this.getValues(item, attribute).length > 0); //Boolean
},
containsValue: function(/* item */ item,
/* attribute || attribute-name-string */ attribute,
/* anything */ value){
// summary:
// See dojo.data.api.Read.containsValue()
var regexp = undefined;
if(typeof value === "string"){
regexp = dojo.data.util.filter.patternToRegExp(value, false);
}
return this._containsValue(item, attribute, value, regexp); //boolean.
},
_containsValue: function( /* item */ item,
/* attribute || attribute-name-string */ attribute,
/* anything */ value,
/* RegExp?*/ regexp){
// summary:
// Internal function for looking at the values contained by the item.
// description:
// Internal function for looking at the values contained by the item. This
// function allows for denoting if the comparison should be case sensitive for
// strings or not (for handling filtering cases where string case should not matter)
//
// item:
// The data item to examine for attribute values.
// attribute:
// The attribute to inspect.
// value:
// The value to match.
// regexp:
// Optional regular expression generated off value if value was of string type to handle wildcarding.
// If present and attribute values are string, then it can be used for comparison instead of 'value'
var values = this.getValues(item, attribute);
for(var i = 0; i < values.length; ++i){
var possibleValue = values[i];
if(typeof possibleValue === "string" && regexp){
return (possibleValue.match(regexp) !== null);
}else{
//Non-string matching.
if(value === possibleValue){
return true; // Boolean
}
}
}
return false; // Boolean
},
isItem: function(/* anything */ something){
// summary:
// See dojo.data.api.Read.isItem()
// description:
// Four things are verified to ensure that "something" is an item:
// something can not be null, the nodeType must be an XML Element,
// the tagName must be "outline", and the node must be a member of
// XML document for this datastore.
return (something &&
something.nodeType == 1 &&
something.tagName == 'outline' &&
something.ownerDocument === this._xmlData); //Boolean
},
isItemLoaded: function(/* anything */ something){
// summary:
// See dojo.data.api.Read.isItemLoaded()
// OpmlStore loads every item, so if it's an item, then it's loaded.
return this.isItem(something); //Boolean
},
loadItem: function(/* item */ item){
// summary:
// See dojo.data.api.Read.loadItem()
// description:
// The OpmlStore always loads all items, so if it's an item, then it's loaded.
// From the dojo.data.api.Read.loadItem docs:
// If a call to isItemLoaded() returns true before loadItem() is even called,
// then loadItem() need not do any work at all and will not even invoke the callback handlers.
},
getLabel: function(/* item */ item){
// summary:
// See dojo.data.api.Read.getLabel()
if(this.isItem(item)){
return this.getValue(item,this.label); //String
}
return undefined; //undefined
},
getLabelAttributes: function(/* item */ item){
// summary:
// See dojo.data.api.Read.getLabelAttributes()
return [this.label]; //array
},
// The dojo.data.api.Read.fetch() function is implemented as
// a mixin from dojo.data.util.simpleFetch.
// That mixin requires us to define _fetchItems().
_fetchItems: function( /* Object */ keywordArgs,
/* Function */ findCallback,
/* Function */ errorCallback){
// summary:
// See dojo.data.util.simpleFetch.fetch()
var self = this;
var filter = function(requestArgs, arrayOfItems){
var items = null;
if(requestArgs.query){
items = [];
var ignoreCase = requestArgs.queryOptions ? requestArgs.queryOptions.ignoreCase : false;
//See if there are any string values that can be regexp parsed first to avoid multiple regexp gens on the
//same value for each item examined. Much more efficient.
var regexpList = {};
for(var key in requestArgs.query){
var value = requestArgs.query[key];
if(typeof value === "string"){
regexpList[key] = dojo.data.util.filter.patternToRegExp(value, ignoreCase);
}
}
for(var i = 0; i < arrayOfItems.length; ++i){
var match = true;
var candidateItem = arrayOfItems[i];
for(var key in requestArgs.query){
var value = requestArgs.query[key];
if(!self._containsValue(candidateItem, key, value, regexpList[key])){
match = false;
}
}
if(match){
items.push(candidateItem);
}
}
}else{
// We want a copy to pass back in case the parent wishes to sort the array. We shouldn't allow resort
// of the internal list so that multiple callers can get lists and sort without affecting each other.
if(arrayOfItems.length> 0){
items = arrayOfItems.slice(0,arrayOfItems.length);
}
}
findCallback(items, requestArgs);
};
if(this._loadFinished){
filter(keywordArgs, this._getItemsArray(keywordArgs.queryOptions));
}else{
//If fetches come in before the loading has finished, but while
//a load is in progress, we have to defer the fetching to be
//invoked in the callback.
if(this._loadInProgress){
this._queuedFetches.push({args: keywordArgs, filter: filter});
}else{
if(this.url !== ""){
this._loadInProgress = true;
var getArgs = {
url: self.url,
handleAs: "xml",
preventCache: self.urlPreventCache
};
var getHandler = dojo.xhrGet(getArgs);
getHandler.addCallback(function(data){
self._processRawXmlTree(data);
filter(keywordArgs, self._getItemsArray(keywordArgs.queryOptions));
self._handleQueuedFetches();
});
getHandler.addErrback(function(error){
throw error;
});
}else if(this._opmlData){
this._processRawXmlTree(this._opmlData);
this._opmlData = null;
filter(keywordArgs, this._getItemsArray(keywordArgs.queryOptions));
}else{
throw new Error("dojox.data.OpmlStore: No OPML source data was provided as either URL or XML data input.");
}
}
}
},
getFeatures: function(){
// summary: See dojo.data.api.Read.getFeatures()
var features = {
'dojo.data.api.Read': true,
'dojo.data.api.Identity': true
};
return features; //Object
},
/***************************************
dojo.data.api.Identity API
***************************************/
getIdentity: function(/* item */ item){
// summary:
// See dojo.data.api.Identity.getIdentity()
if(this.isItem(item)){
//No ther way to do this other than O(n) without
//complete rework of how the tree stores nodes.
for(var i in this._identityMap){
if(this._identityMap[i] === item){
return i;
}
}
}
return null; //null
},
fetchItemByIdentity: function(/* Object */ keywordArgs){
// summary:
// See dojo.data.api.Identity.fetchItemByIdentity()
//Hasn't loaded yet, we have to trigger the load.
if(!this._loadFinished){
var self = this;
if(this.url !== ""){
//If fetches come in before the loading has finished, but while
//a load is in progress, we have to defer the fetching to be
//invoked in the callback.
if(this._loadInProgress){
this._queuedFetches.push({args: keywordArgs});
}else{
this._loadInProgress = true;
var getArgs = {
url: self.url,
handleAs: "xml"
};
var getHandler = dojo.xhrGet(getArgs);
getHandler.addCallback(function(data){
var scope = keywordArgs.scope?keywordArgs.scope:dojo.global;
try{
self._processRawXmlTree(data);
var item = self._identityMap[keywordArgs.identity];
if(!self.isItem(item)){
item = null;
}
if(keywordArgs.onItem){
keywordArgs.onItem.call(scope, item);
}
self._handleQueuedFetches();
}catch(error){
if(keywordArgs.onError){
keywordArgs.onError.call(scope, error);
}
}
});
getHandler.addErrback(function(error){
this._loadInProgress = false;
if(keywordArgs.onError){
var scope = keywordArgs.scope?keywordArgs.scope:dojo.global;
keywordArgs.onError.call(scope, error);
}
});
}
}else if(this._opmlData){
this._processRawXmlTree(this._opmlData);
this._opmlData = null;
var item = this._identityMap[keywordArgs.identity];
if(!self.isItem(item)){
item = null;
}
if(keywordArgs.onItem){
var scope = keywordArgs.scope?keywordArgs.scope:dojo.global;
keywordArgs.onItem.call(scope, item);
}
}
}else{
//Already loaded. We can just look it up and call back.
var item = this._identityMap[keywordArgs.identity];
if(!this.isItem(item)){
item = null;
}
if(keywordArgs.onItem){
var scope = keywordArgs.scope?keywordArgs.scope:dojo.global;
keywordArgs.onItem.call(scope, item);
}
}