1 /*

     2 Copyright (c) 2009, Yahoo! Inc. All rights reserved.

     3 Code licensed under the BSD License:

     4 http://developer.yahoo.net/yui/license.txt

     5 version: 3.0.0

     6 build: 1549

     7 */

     8 YUI.add('dataschema-xml', function(Y) {

     9 

    10 /**

    11  * Provides a DataSchema implementation which can be used to work with XML data.

    12  *

    13  * @module dataschema

    14  * @submodule dataschema-xml

    15  */

    16 var LANG = Y.Lang,

    17 

    18     /**

    19      * XML subclass for the DataSchema Utility.

    20      * @class DataSchema.XML

    21      * @extends DataSchema.Base

    22      * @static

    23      */

    24     SchemaXML = {

    25 

    26         /////////////////////////////////////////////////////////////////////////////

    27         //

    28         // DataSchema.XML static methods

    29         //

    30         /////////////////////////////////////////////////////////////////////////////

    31         /**

    32          * Applies a given schema to given XML data.

    33          *

    34          * @method apply

    35          * @param schema {Object} Schema to apply.

    36          * @param data {XMLDoc} XML document.

    37          * @return {Object} Schema-parsed data.

    38          * @static

    39          */

    40         apply: function(schema, data) {

    41             var xmldoc = data,

    42                 data_out = {results:[],meta:{}};

    43 

    44             if(xmldoc && xmldoc.nodeType && (xmldoc.nodeType === 9 || xmldoc.nodeType === 1 || xmldoc.nodeType === 11) && schema) {

    45                 // Parse results data

    46                 data_out = SchemaXML._parseResults(schema, xmldoc, data_out);

    47 

    48                 // Parse meta data

    49                 data_out = SchemaXML._parseMeta(schema.metaFields, xmldoc, data_out);

    50             }

    51             else {

    52                 data_out.error = new Error("XML schema parse failure");

    53             }

    54 

    55             return data_out;

    56         },

    57 

    58         /**

    59          * Get an XPath-specified value for a given field from an XML node or document.

    60          *

    61          * @method _getLocationValue

    62          * @param field {String | Object} Field definition.

    63          * @param context {Object} XML node or document to search within.

    64          * @return {Object} Data value or null.

    65          * @static

    66          * @protected

    67          */

    68         _getLocationValue: function(field, context) {

    69             var locator = field.locator || field.key || field,

    70                 xmldoc = context.ownerDocument || context,

    71                 result, res, value = null;

    72 

    73             try {

    74                 // Standards mode

    75                 if(!LANG.isUndefined(xmldoc.evaluate)) {

    76                     result = xmldoc.evaluate(locator, context, xmldoc.createNSResolver(!context.ownerDocument ? context.documentElement : context.ownerDocument.documentElement), 0, null);

    77                     while(res = result.iterateNext()) {

    78                         value = res.textContent;

    79                     }

    80                 }

    81                 // IE mode

    82                 else {

    83                     xmldoc.setProperty("SelectionLanguage", "XPath");

    84                     result = context.selectNodes(locator)[0];

    85                     value = result.value || result.text || null;

    86                 }

    87                 return Y.DataSchema.Base.parse(value, field);

    88 

    89             }

    90             catch(e) {

    91             }

    92         },

    93 

    94         /**

    95          * Parses results data according to schema

    96          *

    97          * @method _parseMeta

    98          * @param xmldoc_in {Object} XML document parse.

    99          * @param data_out {Object} In-progress schema-parsed data to update.

   100          * @return {Object} Schema-parsed data.

   101          * @static

   102          * @protected

   103          */

   104         _parseMeta: function(metaFields, xmldoc_in, data_out) {

   105             if(LANG.isObject(metaFields)) {

   106                 var key,

   107                     xmldoc = xmldoc_in.ownerDocument || xmldoc_in;

   108 

   109                 for(key in metaFields) {

   110                     if (metaFields.hasOwnProperty(key)) {

   111                         data_out.meta[key] = SchemaXML._getLocationValue(metaFields[key], xmldoc);

   112                     }

   113                 }

   114             }

   115             return data_out;

   116         },

   117 

   118         /**

   119          * Schema-parsed list of results from full data

   120          *

   121          * @method _parseResults

   122          * @param schema {Object} Schema to parse against.

   123          * @param xmldoc_in {Object} XML document parse.

   124          * @param data_out {Object} In-progress schema-parsed data to update.

   125          * @return {Object} Schema-parsed data.

   126          * @static

   127          * @protected

   128          */

   129         _parseResults: function(schema, xmldoc_in, data_out) {

   130             if(schema.resultListLocator && LANG.isArray(schema.resultFields)) {

   131                 var nodeList = xmldoc_in.getElementsByTagName(schema.resultListLocator),

   132                     fields = schema.resultFields,

   133                     results = [],

   134                     node, field, result, i, j;

   135 

   136                 if(nodeList.length) {

   137                     // Loop through each result node

   138                     for(i=nodeList.length-1; i>= 0; i--) {

   139                         result = {};

   140                         node = nodeList[i];

   141 

   142                         // Find each field value

   143                         for(j=fields.length-1; j>= 0; j--) {

   144                             field = fields[j];

   145                             result[field.key || field] = SchemaXML._getLocationValue(field, node);

   146                         }

   147                         results[i] = result;

   148                     }

   149 

   150                     data_out.results = results;

   151                 }

   152                 else {

   153                     data_out.error = new Error("XML schema result nodes retrieval failure");

   154                 }

   155             }

   156             return data_out;

   157         }

   158     };

   159 

   160 Y.DataSchema.XML = Y.mix(SchemaXML, Y.DataSchema.Base);

   161 

   162 

   163 

   164 }, '3.0.0' ,{requires:['dataschema-base']});