/*
|
Copyright (c) 2007, Yahoo! Inc. All rights reserved.
|
Code licensed under the BSD License:
|
http://developer.yahoo.net/yui/license.txt
|
version: 2.2.0
|
*/
|
/**
|
* The DataSource utility provides a common configurable interface for widgets
|
* to access a variety of data, from JavaScript arrays to online servers over
|
* XHR.
|
*
|
* @module datasource
|
* @requires yahoo, event
|
* @optional xhr
|
* @title DataSource Utility
|
* @beta
|
*/
|
|
/****************************************************************************/
|
/****************************************************************************/
|
/****************************************************************************/
|
|
/**
|
* The DataSource class defines and manages a live set of data for widgets to
|
* interact with. Examples of live databases include in-memory
|
* local data such as a JavaScript array, a JavaScript function, or JSON, or
|
* remote data such as data retrieved through an XHR connection.
|
*
|
* @class DataSource
|
* @uses YAHOO.util.EventProvider
|
* @constructor
|
* @param oLiveData {Object} Pointer to live database
|
* @param oConfigs {Object} (optional) Object literal of configuration values
|
*/
|
YAHOO.util.DataSource = function(oLiveData, oConfigs) {
|
// Set any config params passed in to override defaults
|
if(typeof oConfigs == "object") {
|
for(var sConfig in oConfigs) {
|
if (sConfig) {
|
this[sConfig] = oConfigs[sConfig];
|
}
|
}
|
}
|
|
if(!oLiveData) {
|
return;
|
}
|
else {
|
switch(oLiveData.constructor) {
|
case Function:
|
this.dataType = YAHOO.util.DataSource.TYPE_JSFUNCTION;
|
break;
|
case Array:
|
this.dataType = YAHOO.util.DataSource.TYPE_JSARRAY;
|
break;
|
case String:
|
this.dataType = YAHOO.util.DataSource.TYPE_XHR;
|
break;
|
case Object:
|
this.dataType = YAHOO.util.DataSource.TYPE_JSON;
|
break;
|
default:
|
this.dataType = YAHOO.util.DataSource.TYPE_UNKNOWN;
|
break;
|
}
|
this.liveData = oLiveData;
|
}
|
|
// Validate and initialize public configs
|
var maxCacheEntries = this.maxCacheEntries;
|
if(isNaN(maxCacheEntries) || (maxCacheEntries < 0)) {
|
maxCacheEntries = 0;
|
}
|
|
// Initialize local cache
|
if(maxCacheEntries > 0 && !this._aCache) {
|
this._aCache = [];
|
}
|
|
this._sName = "instance" + YAHOO.util.DataSource._nIndex;
|
YAHOO.util.DataSource._nIndex++;
|
|
|
/////////////////////////////////////////////////////////////////////////////
|
//
|
// Custom Events
|
//
|
/////////////////////////////////////////////////////////////////////////////
|
|
/**
|
* Fired when a request is made to the local cache.
|
*
|
* @event cacheRequestEvent
|
* @param oArgs.request {Object} The request object.
|
* @param oArgs.callback {Function} The callback function.
|
* @param oArgs.caller {Object} The parent object of the callback function.
|
*/
|
this.createEvent("cacheRequestEvent");
|
|
/**
|
* Fired when data is retrieved from the local cache.
|
*
|
* @event getCachedResponseEvent
|
* @param oArgs.request {Object} The request object.
|
* @param oArgs.response {Object} The response object.
|
* @param oArgs.callback {Function} The callback function.
|
* @param oArgs.caller {Object} The parent object of the callback function.
|
*/
|
this.createEvent("cacheResponseEvent");
|
|
/**
|
* Fired when a request is sent to the live data source.
|
*
|
* @event requestEvent
|
* @param oArgs.request {Object} The request object.
|
* @param oArgs.callback {Function} The callback function.
|
* @param oArgs.caller {Object} The parent object of the callback function.
|
*/
|
this.createEvent("requestEvent");
|
|
/**
|
* Fired when live data source sends response.
|
*
|
* @event parseResponseEvent
|
* @param oArgs.request {Object} The request object.
|
* @param oArgs.response {Object} The raw response object.
|
* @param oArgs.callback {Function} The callback function.
|
* @param oArgs.caller {Object} The parent object of the callback function.
|
*/
|
this.createEvent("responseEvent");
|
|
/**
|
* Fired when response is parsed.
|
*
|
* @event responseParseEvent
|
* @param oArgs.request {Object} The request object.
|
* @param oArgs.response {Object} The parsed response object.
|
* @param oArgs.callback {Function} The callback function.
|
* @param oArgs.caller {Object} The parent object of the callback function.
|
*/
|
this.createEvent("responseParseEvent");
|
|
/**
|
* Fired when response is cached.
|
*
|
* @event responseCacheEvent
|
* @param oArgs.request {Object} The request object.
|
* @param oArgs.response {Object} The parsed response object.
|
* @param oArgs.callback {Function} The callback function.
|
* @param oArgs.caller {Object} The parent object of the callback function.
|
*/
|
this.createEvent("responseCacheEvent");
|
/**
|
* Fired when an error is encountered with the live data source.
|
*
|
* @event dataErrorEvent
|
* @param oArgs.request {Object} The request object.
|
* @param oArgs.callback {Function} The callback function.
|
* @param oArgs.caller {Object} The parent object of the callback function.
|
* @param oArgs.message {String} The error message.
|
*/
|
this.createEvent("dataErrorEvent");
|
|
/**
|
* Fired when the local cache is flushed.
|
*
|
* @event cacheFlushEvent
|
*/
|
this.createEvent("cacheFlushEvent");
|
};
|
|
YAHOO.augment(YAHOO.util.DataSource, YAHOO.util.EventProvider);
|
|
/////////////////////////////////////////////////////////////////////////////
|
//
|
// Public constants
|
//
|
/////////////////////////////////////////////////////////////////////////////
|
|
/**
|
* Type is unknown.
|
*
|
* @property TYPE_UNKNOWN
|
* @type Number
|
* @final
|
* @default -1
|
*/
|
YAHOO.util.DataSource.TYPE_UNKNOWN = -1;
|
|
/**
|
* Type is a JavaScript Array.
|
*
|
* @property TYPE_JSARRAY
|
* @type Number
|
* @final
|
* @default 0
|
*/
|
YAHOO.util.DataSource.TYPE_JSARRAY = 0;
|
|
/**
|
* Type is a JavaScript Function.
|
*
|
* @property TYPE_JSFUNCTIOn
|
* @type Number
|
* @final
|
* @default 1
|
*/
|
YAHOO.util.DataSource.TYPE_JSFUNCTION = 1;
|
|
/**
|
* Type is hosted on a server via an XHR connection.
|
*
|
* @property TYPE_XHR
|
* @type Number
|
* @final
|
* @default 2
|
*/
|
YAHOO.util.DataSource.TYPE_XHR = 2;
|
|
/**
|
* Type is JSON.
|
*
|
* @property TYPE_JSON
|
* @type Number
|
* @final
|
* @default 3
|
*/
|
YAHOO.util.DataSource.TYPE_JSON = 3;
|
|
/**
|
* Type is XML.
|
*
|
* @property TYPE_XML
|
* @type Number
|
* @final
|
* @default 4
|
*/
|
YAHOO.util.DataSource.TYPE_XML = 4;
|
|
/**
|
* Type is plain text.
|
*
|
* @property TYPE_TEXT
|
* @type Number
|
* @final
|
* @default 5
|
*/
|
YAHOO.util.DataSource.TYPE_TEXT = 5;
|
/**
|
* Error message for invalid data responses.
|
*
|
* @property ERROR_DATAINVALID
|
* @type String
|
* @final
|
* @default "Invalid data"
|
*/
|
YAHOO.util.DataSource.ERROR_DATAINVALID = "Invalid data";
|
|
/**
|
* Error message for null data responses.
|
*
|
* @property ERROR_DATANULL
|
* @type String
|
* @final
|
* @default "Null data"
|
*/
|
YAHOO.util.DataSource.ERROR_DATANULL = "Null data";
|
|
/////////////////////////////////////////////////////////////////////////////
|
//
|
// Private member variables
|
//
|
/////////////////////////////////////////////////////////////////////////////
|
|
/**
|
* Internal class variable to index multiple DataSource instances.
|
*
|
* @property _nIndex
|
* @type Number
|
* @private
|
*/
|
YAHOO.util.DataSource._nIndex = 0;
|
|
/**
|
* Name of DataSource instance.
|
*
|
* @property _sName
|
* @type String
|
* @private
|
*/
|
YAHOO.util.DataSource.prototype._sName = null;
|
|
/**
|
* Local cache of data result objects indexed chronologically.
|
*
|
* @property _aCache
|
* @type Object[]
|
* @private
|
*/
|
YAHOO.util.DataSource.prototype._aCache = null;
|
|
/////////////////////////////////////////////////////////////////////////////
|
//
|
// Private methods
|
//
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
/////////////////////////////////////////////////////////////////////////////
|
//
|
// Public member variables
|
//
|
/////////////////////////////////////////////////////////////////////////////
|
|
/**
|
* Max size of the local cache. Set to 0 to turn off caching. Caching is
|
* useful to reduce the number of server connections. Recommended only for data
|
* sources that return comprehensive results for queries or when stale data is
|
* not an issue.
|
*
|
* @property maxCacheEntries
|
* @type Number
|
* @default 0
|
*/
|
YAHOO.util.DataSource.prototype.maxCacheEntries = 0;
|
|
/**
|
* Pointer to live database.
|
*
|
* @property liveData
|
* @type Object
|
*/
|
YAHOO.util.DataSource.prototype.liveData = null;
|
|
/**
|
* If data is accessed over XHR via Connection Manager, the connection timeout is
|
* configurable in milliseconds the XHR connection will wait for a server
|
* response. A a value of zero indicates the XHR connection will wait forever.
|
* Any value greater than zero will use the Connection utility's Auto-Abort
|
* feature.
|
*
|
* @property connTimeout
|
* @type Number
|
* @default 0
|
*/
|
YAHOO.util.DataSource.prototype.connTimeout = null;
|
|
/**
|
* Alias to YUI Connection Manager. Allows implementers to specify their own
|
* subclasses of the YUI Connection Manager utility.
|
*
|
* @property connMgr
|
* @type Object
|
* @default YAHOO.util.Connect
|
*/
|
YAHOO.util.DataSource.prototype.connMgr = YAHOO.util.Connect || null;
|
|
/**
|
* Where the live data is held.
|
*
|
* @property dataType
|
* @type Number
|
* @default YAHOO.util.DataSource.TYPE_UNKNOWN
|
*
|
*/
|
YAHOO.util.DataSource.prototype.dataType = YAHOO.util.DataSource.TYPE_UNKNOWN;
|
|
/**
|
* Format of response.
|
*
|
* @property responseType
|
* @type Number
|
* @default YAHOO.util.DataSource.TYPE_UNKNOWN
|
*/
|
YAHOO.util.DataSource.prototype.responseType = YAHOO.util.DataSource.TYPE_UNKNOWN;
|
|
/////////////////////////////////////////////////////////////////////////////
|
//
|
// Public methods
|
//
|
/////////////////////////////////////////////////////////////////////////////
|
|
/**
|
* Public accessor to the unique name of the DataSource instance.
|
*
|
* @method toString
|
* @return {String} Unique name of the DataSource instance.
|
*/
|
YAHOO.util.DataSource.prototype.toString = function() {
|
return "DataSource " + this._sName;
|
};
|
|
/**
|
* Overridable method passes request to cache and returns cached response if any,
|
* refreshing the hit in the cache as the newest item. Returns null if there is
|
* no cache hit.
|
*
|
* @method getCachedResponse
|
* @param oRequest {Object} Request object.
|
* @param oCallback {Function} Handler function to receive the response
|
* @param oCaller {Object} The Calling object that is making the request
|
* @return {Object} Cached response object or null.
|
*/
|
YAHOO.util.DataSource.prototype.getCachedResponse = function(oRequest, oCallback, oCaller) {
|
var aCache = this._aCache;
|
var nCacheLength = (aCache) ? aCache.length : 0;
|
var oResponse = null;
|
|
// If cache is enabled...
|
if((this.maxCacheEntries > 0) && aCache && (nCacheLength > 0)) {
|
this.fireEvent("cacheRequestEvent", {request:oRequest,callback:oCallback,caller:oCaller});
|
|
// Loop through each cached element
|
for(var i = nCacheLength-1; i >= 0; i--) {
|
var oCacheElem = aCache[i];
|
|
// Defer cache hit logic to a public overridable method
|
if(this.isCacheHit(oRequest,oCacheElem.request)) {
|
// Grab the cached response
|
oResponse = oCacheElem.response;
|
// The cache returned a hit!
|
// Remove element from its original location
|
aCache.splice(i,1);
|
// Add as newest
|
this.addToCache(oRequest, oResponse);
|
this.fireEvent("cacheResponseEvent", {request:oRequest,response:oResponse,callback:oCallback,caller:oCaller});
|
break;
|
}
|
}
|
}
|
return oResponse;
|
};
|
|
/**
|
* Default overridable method matches given request to given cached request.
|
* Returns true if is a hit, returns false otherwise. Implementers should
|
* override this method to customize the cache-matching algorithm.
|
*
|
* @method isCacheHit
|
* @param oRequest {Object} Request object.
|
* @param oCachedRequest {Object} Cached request object.
|
* @return {Boolean} True if given request matches cached request, false otherwise.
|
*/
|
YAHOO.util.DataSource.prototype.isCacheHit = function(oRequest, oCachedRequest) {
|
return (oRequest === oCachedRequest);
|
};
|
|
/**
|
* Adds a new item to the cache. If cache is full, evicts the stalest item
|
* before adding the new item.
|
*
|
* @method addToCache
|
* @param oRequest {Object} Request object.
|
* @param oResponse {Object} Response object to cache.
|
*/
|
YAHOO.util.DataSource.prototype.addToCache = function(oRequest, oResponse) {
|
//TODO: check for duplicate entries
|
var aCache = this._aCache;
|
// Don't add if anything important is missing.
|
if(!aCache || !oRequest || !oResponse) {
|
return;
|
}
|
|
// If the cache is full, make room by removing stalest element (index=0)
|
while(aCache.length >= this.maxCacheEntries) {
|
aCache.shift();
|
}
|
|
// Add to cache in the newest position, at the end of the array
|
var oCacheElem = {request:oRequest,response:oResponse};
|
aCache.push(oCacheElem);
|
this.fireEvent("responseCacheEvent",{request:oRequest,response:oResponse});
|
|
};
|
|
/**
|
* Flushes cache.
|
*
|
* @method flushCache
|
*/
|
YAHOO.util.DataSource.prototype.flushCache = function() {
|
if(this._aCache) {
|
this._aCache = [];
|
}
|
this.fireEvent("cacheFlushEvent");
|
};
|
|
/**
|
* First looks for cached response, then sends request to live data.
|
*
|
* @method sendRequest
|
* @param oRequest {Object} Request object
|
* @param oCallback {Function} Handler function to receive the response
|
* @param oCaller {Object} The Calling object that is making the request
|
*/
|
YAHOO.util.DataSource.prototype.sendRequest = function(oRequest, oCallback, oCaller) {
|
// First look in cache
|
var oCachedResponse = this.getCachedResponse(oRequest, oCallback, oCaller);
|
if(oCachedResponse) {
|
oCallback.call(oCaller, oRequest, oCachedResponse);
|
return;
|
}
|
|
// Not in cache, so forward request to live data
|
this.makeConnection(oRequest, oCallback, oCaller);
|
};
|
|
/**
|
* Overridable method provides default functionality to make a connection to
|
* live data in order to send request. The response coming back is then
|
* forwarded to the handleResponse function. This method should be customized
|
* for more complex implementations.
|
*
|
* @method makeConnection
|
* @param oRequest {Object} Request object.
|
* @param oCallback {Function} Handler function to receive the response
|
* @param oCaller {Object} The Calling object that is making the request
|
*/
|
YAHOO.util.DataSource.prototype.makeConnection = function(oRequest, oCallback, oCaller) {
|
this.fireEvent("requestEvent", {request:oRequest,callback:oCallback,caller:oCaller});
|
var oRawResponse = null;
|
|
// How to make the connection depends on the type of data
|
switch(this.dataType) {
|
|
// If the live data is a JavaScript Array
|
// simply forward the entire array to the handler
|
case YAHOO.util.DataSource.TYPE_JSARRAY:
|
case YAHOO.util.DataSource.TYPE_JSON:
|
oRawResponse = this.liveData;
|
this.handleResponse(oRequest, oRawResponse, oCallback, oCaller);
|
break;
|
|
// If the live data is a JavaScript Function
|
// pass the request in as a parameter and
|
// forward the return value to the handler
|
case YAHOO.util.DataSource.TYPE_JSFUNCTION:
|
oRawResponse = this.liveData(oRequest);
|
this.handleResponse(oRequest, oRawResponse, oCallback, oCaller);
|
break;
|
|
// If the live data is over Connection Manager
|
// set up the callback object and
|
// pass the request in as a URL query and
|
// forward the response to the handler
|
case YAHOO.util.DataSource.TYPE_XHR:
|
/**
|
* Connection Manager success handler
|
*
|
* @method _xhrSuccess
|
* @param oResponse {Object} HTTPXMLRequest object
|
* @private
|
*/
|
var _xhrSuccess = function(oResponse) {
|
// Error if no response
|
if(!oResponse) {
|
this.fireEvent("dataErrorEvent", {request:oRequest,callback:oCallback,caller:oCaller,message:YAHOO.util.DataSource.ERROR_DATANULL});
|
return null;
|
}
|
// Error if response ID does not match last made request ID.
|
else if(!this._oConn || (oResponse.tId != this._oConn.tId)) {
|
this.fireEvent("dataErrorEvent", {request:oRequest,callback:oCallback,caller:oCaller,message:YAHOO.util.DataSource.ERROR_DATAINVALID});
|
return null;
|
}
|
// Forward to handler
|
else {
|
this.handleResponse(oRequest, oResponse, oCallback, oCaller);
|
}
|
};
|
|
/**
|
* Connection Manager failure handler
|
*
|
* @method _xhrFailure
|
* @param oResponse {Object} HTTPXMLRequest object
|
* @private
|
*/
|
var _xhrFailure = function(oResponse) {
|
this.fireEvent("dataErrorEvent", {request:oRequest,callback:oCallback,caller:oCaller,message:YAHOO.util.DataSource.ERROR_DATAXHR});
|
return null;
|
};
|
|
/**
|
* Connection Manager callback object
|
*
|
* @property _xhrCallback
|
* @param oResponse {Object} HTTPXMLRequest object
|
* @private
|
*/
|
var _xhrCallback = {
|
success:_xhrSuccess,
|
failure:_xhrFailure,
|
scope: this
|
};
|
|
//TODO: connTimeout config
|
if(this.connTimeout && !isNaN(this.connTimeout) && this.connTimeout > 0) {
|
_xhrCallback.timeout = this.connTimeout;
|
}
|
|
//TODO: oConn config
|
if(this._oConn && this.connMgr) {
|
this.connMgr.abort(this._oConn);
|
}
|
|
var sUri = this.liveData+"?"+oRequest;
|
if(this.connMgr) {
|
this._oConn = this.connMgr.asyncRequest("GET", sUri, _xhrCallback, null);
|
}
|
else {
|
}
|
|
break;
|
default:
|
//TODO: any default?
|
break;
|
}
|
};
|
|
/**
|
* Handles raw data response from live data source.
|
*
|
* @method handleResponse
|
* @param oRequest {Object} Request object
|
* @param oRawResponse {Object} The raw response from the live database
|
* @param oCallback {Function} Handler function to receive the response
|
* @param oCaller {Object} The calling object that is making the request
|
*/
|
YAHOO.util.DataSource.prototype.handleResponse = function(oRequest, oRawResponse, oCallback, oCaller) {
|
this.fireEvent("responseEvent", {request:oRequest,response:oRawResponse,callback:oCallback,caller:oCaller});
|
var xhr = (this.dataType == YAHOO.util.DataSource.TYPE_XHR) ? true : false;
|
var oParsedResponse = null;
|
//TODO: break out into overridable methods
|
switch(this.responseType) {
|
case YAHOO.util.DataSource.TYPE_JSARRAY:
|
if(xhr && oRawResponse.responseText) {
|
oRawResponse = oRawResponse.responseText;
|
}
|
oParsedResponse = this.parseArrayData(oRequest, oRawResponse);
|
break;
|
case YAHOO.util.DataSource.TYPE_JSON:
|
if(xhr && oRawResponse.responseText) {
|
oRawResponse = oRawResponse.responseText;
|
}
|
oParsedResponse = this.parseJSONData(oRequest, oRawResponse);
|
break;
|
case YAHOO.util.DataSource.TYPE_XML:
|
if(xhr && oRawResponse.responseXML) {
|
oRawResponse = oRawResponse.responseXML;
|
}
|
oParsedResponse = this.parseXMLData(oRequest, oRawResponse);
|
break;
|
case YAHOO.util.DataSource.TYPE_TEXT:
|
if(xhr && oRawResponse.responseText) {
|
oRawResponse = oRawResponse.responseText;
|
}
|
oParsedResponse = this.parseTextData(oRequest, oRawResponse);
|
break;
|
default:
|
//TODO: pass off to custom function
|
//var contentType = oRawResponse.getResponseHeader["Content-Type"];
|
break;
|
}
|
|
if(oParsedResponse) {
|
this.fireEvent("responseParseEvent", {request:oRequest,response:oParsedResponse,callback:oCallback,caller:oCaller});
|
// Cache the response
|
this.addToCache(oRequest, oParsedResponse);
|
}
|
else {
|
this.fireEvent("dataErrorEvent", {request:oRequest,callback:oCallback,caller:oCaller,message:YAHOO.util.DataSource.ERROR_DATANULL});
|
}
|
|
// Send the response back to the caller
|
oCallback.call(oCaller, oRequest, oParsedResponse);
|
};
|
|
/**
|
* Overridable method parses raw array data into a response object.
|
*
|
* @method parseArrayData
|
* @param oRequest {Object} Request object.
|
* @param oRawResponse {Object} The raw response from the live database
|
* @return {Object} Parsed response object
|
*/
|
YAHOO.util.DataSource.prototype.parseArrayData = function(oRequest, oRawResponse) {
|
var oParsedResponse = [];
|
var fields = this.responseSchema.fields;
|
for(var i=oRawResponse.length-1; i>-1; i--) {
|
var oResult = {};
|
for(var j=fields.length; j>-1; j--) {
|
oResult[fields[j]] = oRawResponse[i][j] || oRawResponse[i][fields[j]];
|
}
|
oParsedResponse.unshift(oResult);
|
}
|
return oParsedResponse;
|
};
|
|
/**
|
* Overridable method parses raw plain text data into a response object.
|
*
|
* @method parseTextData
|
* @param oRequest {Object} Request object
|
* @param oRawResponse {Object} The raw response from the live database
|
* @return {Object} Parsed response object
|
*/
|
YAHOO.util.DataSource.prototype.parseTextData = function(oRequest, oRawResponse) {
|
var oParsedResponse = [];
|
var recDelim = this.responseSchema.recordDelim;
|
var fieldDelim = this.responseSchema.fieldDelim;
|
var aSchema = this.responseSchema.fields;
|
if(oRawResponse.length > 0) {
|
// Delete the last line delimiter at the end of the data if it exists
|
var newLength = oRawResponse.length-recDelim.length;
|
if(oRawResponse.substr(newLength) == recDelim) {
|
oRawResponse = oRawResponse.substr(0, newLength);
|
}
|
// Split along record delimiter to get an array of strings
|
var recordsarray = oRawResponse.split(recDelim);
|
// Cycle through each record, except the first which contains header info
|
for(var i = recordsarray.length-1; i >= 1; i--) {
|
var dataobject = {};
|
for(var j=aSchema.length-1; j >= 0; j--) {
|
// Split along field delimter to get each data value
|
var fielddataarray = recordsarray[i].split(fieldDelim);
|
|
// Remove quotation marks from edges, if applicable
|
var string = fielddataarray[j];
|
if(string.charAt(0) == "\"") {
|
string = string.substr(1);
|
}
|
if(string.charAt(string.length-1) == "\"") {
|
string = string.substr(0,string.length-1);
|
}
|
dataobject[aSchema[j]] = string;
|
}
|
oParsedResponse.push(dataobject);
|
}
|
}
|
return oParsedResponse;
|
};
|
|
/**
|
* Overridable method parses raw XML data into a response object.
|
*
|
* @method parseXMLData
|
* @param oRequest {Object} Request object
|
* @param oRawResponse {Object} The raw response from the live database
|
* @return {Object} Parsed response object
|
*/
|
YAHOO.util.DataSource.prototype.parseXMLData = function(oRequest, oRawResponse) {
|
var bError = false;
|
var oParsedResponse = [];
|
var xmlList = oRawResponse.getElementsByTagName(this.responseSchema.resultNode);
|
if(!xmlList) {
|
bError = true;
|
}
|
// Loop through each result
|
else {
|
for(var k = xmlList.length-1; k >= 0 ; k--) {
|
var result = xmlList.item(k);
|
var oResult = {};
|
// Loop through each data field in each result using the schema
|
for(var m = this.responseSchema.fields.length-1; m >= 0 ; m--) {
|
var field = this.responseSchema.fields[m];
|
var sValue = null;
|
// Values may be held in an attribute...
|
var xmlAttr = result.attributes.getNamedItem(field);
|
if(xmlAttr) {
|
sValue = xmlAttr.value;
|
}
|
// ...or in a node
|
else {
|
var xmlNode = result.getElementsByTagName(field);
|
if(xmlNode && xmlNode.item(0) && xmlNode.item(0).firstChild) {
|
sValue = xmlNode.item(0).firstChild.nodeValue;
|
}
|
else {
|
sValue = "";
|
}
|
}
|
// Capture the schema-mapped data field values into an array
|
oResult[field] = sValue;
|
}
|
// Capture each array of values into an array of results
|
oParsedResponse.unshift(oResult);
|
}
|
}
|
if(bError) {
|
return null;
|
}
|
return oParsedResponse;
|
};
|
|
/**
|
* Overridable method parses raw JSON data into a response object.
|
*
|
* @method parseJSONData
|
* @param oRequest {Object} Request object
|
* @param oRawResponse {Object} The raw response from the live database
|
* @return {Object} Parsed response object
|
*/
|
YAHOO.util.DataSource.prototype.parseJSONData = function(oRequest, oRawResponse) {
|
//TODO: validate oRawResponse
|
var bError = false;
|
var oParsedResponse = [];
|
var aSchema = this.responseSchema.fields;
|
|
var jsonObj,jsonList;
|
if(oRawResponse) {
|
// Parse JSON object out if it's a string
|
if(oRawResponse.constructor == String) {
|
// Check for latest JSON lib but divert KHTML clients
|
if(oRawResponse.parseJSON && (navigator.userAgent.toLowerCase().indexOf('khtml')== -1)) {
|
// Use the new JSON utility if available
|
jsonObj = oRawResponse.parseJSON();
|
if(!jsonObj) {
|
bError = true;
|
}
|
}
|
// Check for older JSON lib but divert KHTML clients
|
else if(window.JSON && JSON.parse && (navigator.userAgent.toLowerCase().indexOf('khtml')== -1)) {
|
// Use the JSON utility if available
|
jsonObj = JSON.parse(oRawResponse);
|
if(!jsonObj) {
|
bError = true;
|
}
|
}
|
// No JSON lib found so parse the string
|
else {
|
try {
|
// Trim leading spaces
|
while (oRawResponse.length > 0 &&
|
(oRawResponse.charAt(0) != "{") &&
|
(oRawResponse.charAt(0) != "[")) {
|
oRawResponse = oRawResponse.substring(1, oResponse.length);
|
}
|
|
if(oRawResponse.length > 0) {
|
// Strip extraneous stuff at the end
|
var objEnd = Math.max(oRawResponse.lastIndexOf("]"),oRawResponse.lastIndexOf("}"));
|
oRawResponse = oRawResponse.substring(0,objEnd+1);
|
|
// Turn the string into an object literal...
|
// ...eval is necessary here
|
jsonObj = eval("(" + oRawResponse + ")");
|
if(!jsonObj) {
|
bError = true;
|
}
|
|
}
|
}
|
catch(e) {
|
bError = true;
|
}
|
}
|
}
|
// Response must already be a JSON object
|
else if(oRawResponse.constructor == Object) {
|
jsonObj = oRawResponse;
|
}
|
// Now that we have a JSON object, parse a jsonList out of it
|
if(jsonObj && jsonObj.constructor == Object) {
|
try {
|
// eval is necessary here since schema can be of unknown depth
|
jsonList = eval("jsonObj." + this.responseSchema.resultsList);
|
}
|
catch(e) {
|
bError = true;
|
}
|
}
|
}
|
if(bError || !jsonList) {
|
// Something went wrong
|
return null;
|
}
|
|
if(jsonList.constructor != Array) {
|
jsonList = [jsonList];
|
}
|
|
// Loop through the array of all responses...
|
for(var i = jsonList.length-1; i >= 0 ; i--) {
|
var oResult = {};
|
var jsonResult = jsonList[i];
|
// ...and loop through each data field value of each response
|
for(var j = aSchema.length-1; j >= 0 ; j--) {
|
// ...and capture data into an array mapped according to the schema...
|
var dataFieldValue = jsonResult[aSchema[j]];
|
if(!dataFieldValue) {
|
dataFieldValue = "";
|
}
|
oResult[aSchema[j]] = dataFieldValue;
|
}
|
// Capture the array of data field values in an array of results
|
oParsedResponse.unshift(oResult);
|
}
|
return oParsedResponse;
|
};
|
|
YAHOO.register("datasource", YAHOO.util.DataSource, {version: "2.2.0", build: "127"});
|
