dojo.provide("dojox.data.KeyValueStore"); dojo.require("dojo.data.util.filter"); dojo.require("dojo.data.util.simpleFetch"); dojo.declare("dojox.data.KeyValueStore", null, { // summary: // This is a dojo.data store implementation. It can take in either a Javascript // array, JSON string, or URL as the data source. Data is expected to be in the // following format: // [ // { "key1": "value1" }, // { "key2": "value2" } // ] // This is to mimic the Java Properties file format. Each 'item' from this store // is a JS object representing a key-value pair. If an item in the above array has // more than one key/value pair, only the first will be used/accessed. constructor: function(/* Object */ keywordParameters){ // summary: constructor // keywordParameters: {url: String} // keywordParameters: {data: string} // keywordParameters: {dataVar: jsonObject} if(keywordParameters.url){ this.url = keywordParameters.url; } this._keyValueString = keywordParameters.data; this._keyValueVar = keywordParameters.dataVar; this._keyAttribute = "key"; this._valueAttribute = "value"; this._storeProp = "_keyValueStore"; this._features = { 'dojo.data.api.Read': true, 'dojo.data.api.Identity': true }; this._loadInProgress = false; //Got to track the initial load to prevent duelling loads of the dataset. this._queuedFetches = []; }, url: "", data: "", _assertIsItem: function(/* item */ item){ // summary: // This function tests whether the item passed in is indeed an item in the store. // item: // The item to test for being contained by the store. if(!this.isItem(item)){ throw new Error("dojox.data.KeyValueStore: a function was passed an item argument that was not an item"); } }, _assertIsAttribute: function(/* item */ 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.KeyValueStore: a function was passed an attribute argument that was not an attribute object nor an attribute name string"); } }, /*************************************** dojo.data.api.Read API ***************************************/ getValue: function( /* item */ item, /* attribute-name-string */ attribute, /* value? */ defaultValue){ // summary: // See dojo.data.api.Read.getValue() this._assertIsItem(item); this._assertIsAttribute(item, attribute); var value; if(attribute == this._keyAttribute){ // Looking for key value = item[this._keyAttribute]; }else{ value = item[this._valueAttribute]; // Otherwise, attribute == ('value' || the actual key ) } if(value === undefined){ value = defaultValue; } return value; }, getValues: function(/* item */ item, /* attribute-name-string */ attribute){ // summary: // See dojo.data.api.Read.getValues() // Key/Value syntax does not support multi-valued attributes, so this is just a // wrapper function for getValue(). var value = this.getValue(item, attribute); return (value ? [value] : []); //Array }, getAttributes: function(/* item */ item){ // summary: // See dojo.data.api.Read.getAttributes() return [this._keyAttribute, this._valueAttribute, item[this._keyAttribute]]; }, hasAttribute: function( /* item */ item, /* attribute-name-string */ attribute){ // summary: // See dojo.data.api.Read.hasAttribute() this._assertIsItem(item); this._assertIsAttribute(item, attribute); return (attribute == this._keyAttribute || attribute == this._valueAttribute || attribute == item[this._keyAttribute]); }, containsValue: function(/* item */ item, /* 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() if (something && something[this._storeProp] === this) { return true; //Boolean } return false; //Boolean }, isItemLoaded: function(/* anything */ something) { // summary: // See dojo.data.api.Read.isItemLoaded() // The KeyValueStore always loads all items, so if it's an item, then it's loaded. return this.isItem(something); //Boolean }, loadItem: function(/* object */ keywordArgs){ // summary: // See dojo.data.api.Read.loadItem() // description: // The KeyValueStore 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. }, getFeatures: function(){ // summary: // See dojo.data.api.Read.getFeatures() return this._features; //Object }, close: function(/*dojo.data.api.Request || keywordArgs || null */ request){ // summary: // See dojo.data.api.Read.close() }, getLabel: function(/* item */ item){ // summary: // See dojo.data.api.Read.getLabel() return item[this._keyAttribute]; }, getLabelAttributes: function(/* item */ item){ // summary: // See dojo.data.api.Read.getLabelAttributes() return [this._keyAttribute]; }, // 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, arrayOfAllItems){ 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 < arrayOfAllItems.length; ++i){ var match = true; var candidateItem = arrayOfAllItems[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 if(requestArgs.identity){ items = []; var item; for(var key in arrayOfAllItems){ item = arrayOfAllItems[key]; if(item[self._keyAttribute] == requestArgs.identity){ items.push(item); break; } } }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(arrayOfAllItems.length> 0){ items = arrayOfAllItems.slice(0,arrayOfAllItems.length); } } findCallback(items, requestArgs); }; if(this._loadFinished){ filter(keywordArgs, this._arrayOfAllItems); }else{ 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, filter: filter}); }else{ this._loadInProgress = true; var getArgs = { url: self.url, handleAs: "json-comment-filtered" }; var getHandler = dojo.xhrGet(getArgs); getHandler.addCallback(function(data){ self._processData(data); filter(keywordArgs, self._arrayOfAllItems); self._handleQueuedFetches(); }); getHandler.addErrback(function(error){ self._loadInProgress = false; throw error; }); } }else if(this._keyValueString){ this._processData(eval(this._keyValueString)); this._keyValueString = null; filter(keywordArgs, this._arrayOfAllItems); }else if(this._keyValueVar){ this._processData(this._keyValueVar); this._keyValueVar = null; filter(keywordArgs, this._arrayOfAllItems); }else{ throw new Error("dojox.data.KeyValueStore: No source data was provided as either URL, String, or Javascript variable data input."); } } }, _handleQueuedFetches: function(){ // summary: // Internal function to execute delayed request in the store. //Execute any deferred fetches now. if(this._queuedFetches.length > 0){ for(var i = 0; i < this._queuedFetches.length; i++){ var fData = this._queuedFetches[i]; var delayedFilter = fData.filter; var delayedQuery = fData.args; if(delayedFilter){ delayedFilter(delayedQuery, this._arrayOfAllItems); }else{ this.fetchItemByIdentity(fData.args); } } this._queuedFetches = []; } }, _processData: function(/* Array */ data){ this._arrayOfAllItems = []; for(var i=0; i