1 /*

     2 YUI 3.10.3 (build 2fb5187)

     3 Copyright 2013 Yahoo! Inc. All rights reserved.

     4 Licensed under the BSD License.

     5 http://yuilibrary.com/license/

     6 */

     7 

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

     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 

    17 /**

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

    19 

    20 See the `apply` method for usage.

    21 

    22 @class DataSchema.XML

    23 @extends DataSchema.Base

    24 @static

    25 **/

    26 var Lang = Y.Lang,

    27 

    28     okNodeType = {

    29         1 : true,

    30         9 : true,

    31         11: true

    32     },

    33 

    34     SchemaXML;

    35 

    36 SchemaXML = {

    37 

    38     ////////////////////////////////////////////////////////////////////////////

    39     //

    40     // DataSchema.XML static methods

    41     //

    42     ////////////////////////////////////////////////////////////////////////////

    43     /**

    44     Applies a schema to an XML data tree, returning a normalized object with

    45     results in the `results` property. Additional information can be parsed out

    46     of the XML for inclusion in the `meta` property of the response object.  If

    47     an error is encountered during processing, an `error` property will be

    48     added.

    49 

    50     Field data in the nodes captured by the XPath in _schema.resultListLocator_

    51     is extracted with the field identifiers described in _schema.resultFields_.

    52     Field identifiers are objects with the following properties:

    53 

    54       * `key`    : <strong>(required)</strong> The desired property name to use

    55             store the retrieved value in the result object.  If `locator` is

    56             not specified, `key` is also used as the XPath locator (String)

    57       * `locator`: The XPath locator to the node or attribute within each

    58             result node found by _schema.resultListLocator_ containing the

    59             desired field data (String)

    60       * `parser` : A function or the name of a function on `Y.Parsers` used

    61             to convert the input value into a normalized type.  Parser

    62             functions are passed the value as input and are expected to

    63             return a value.

    64       * `schema` : Used to retrieve nested field data into an array for

    65             assignment as the result field value.  This object follows the same

    66             conventions as _schema_.

    67 

    68     If no value parsing or nested parsing is needed, you can use XPath locators

    69     (strings) instead of field identifiers (objects) -- see example below.

    70 

    71     `response.results` will contain an array of objects with key:value pairs.

    72     The keys are the field identifier `key`s, and the values are the data

    73     values extracted from the nodes or attributes found by the field `locator`

    74     (or `key` fallback).

    75     

    76     To extract additional information from the XML, include an array of

    77     XPath locators in _schema.metaFields_.  The collected values will be

    78     stored in `response.meta` with the XPath locator as keys.

    79 

    80     @example

    81         var schema = {

    82                 resultListLocator: '//produce/item',

    83                 resultFields: [

    84                     {

    85                         locator: 'name',

    86                         key: 'name'

    87                     },

    88                     {

    89                         locator: 'color',

    90                         key: 'color',

    91                         parser: function (val) { return val.toUpperCase(); }

    92                     }

    93                 ]

    94             };

    95 

    96         // Assumes data like

    97         // <inventory>

    98         //   <produce>

    99         //     <item><name>Banana</name><color>yellow</color></item>

   100         //     <item><name>Orange</name><color>orange</color></item>

   101         //     <item><name>Eggplant</name><color>purple</color></item>

   102         //   </produce>

   103         // </inventory>

   104 

   105         var response = Y.DataSchema.JSON.apply(schema, data);

   106 

   107         // response.results[0] is { name: "Banana", color: "YELLOW" }

   108      

   109     @method apply

   110     @param {Object} schema Schema to apply.  Supported configuration

   111         properties are:

   112       @param {String} [schema.resultListLocator] XPath locator for the

   113           XML nodes that contain the data to flatten into `response.results`

   114       @param {Array} [schema.resultFields] Field identifiers to

   115           locate/assign values in the response records. See above for

   116           details.

   117       @param {Array} [schema.metaFields] XPath locators to extract extra

   118           non-record related information from the XML data

   119     @param {XMLDoc} data XML data to parse

   120     @return {Object} An Object with properties `results` and `meta`

   121     @static

   122     **/

   123     apply: function(schema, data) {

   124         var xmldoc = data, // unnecessary variables

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

   126 

   127         if (xmldoc && okNodeType[xmldoc.nodeType] && schema) {

   128             // Parse results data

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

   130 

   131             // Parse meta data

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

   133         } else {

   134             Y.log("XML data could not be schema-parsed: " + Y.dump(data) + " " + Y.dump(data), "error", "dataschema-xml");

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

   136         }

   137 

   138         return data_out;

   139     },

   140 

   141     /**

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

   143      *

   144      * @method _getLocationValue

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

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

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

   148      * @static

   149      * @protected

   150      */

   151     _getLocationValue: function(field, context) {

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

   153             xmldoc = context.ownerDocument || context,

   154             result, res, value = null;

   155 

   156         try {

   157             result = SchemaXML._getXPathResult(locator, context, xmldoc);

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

   159                 value = res.textContent || res.value || res.text || res.innerHTML || res.innerText || null;

   160             }

   161 

   162             // FIXME: Why defer to a method that is mixed into this object?

   163             // DSchema.Base is mixed into DSchema.XML (et al), so

   164             // DSchema.XML.parse(...) will work.  This supports the use case

   165             // where DSchema.Base.parse is changed, and that change is then

   166             // seen by all DSchema.* implementations, but does not support the

   167             // case where redefining DSchema.XML.parse changes behavior. In

   168             // fact, DSchema.XML.parse is never even called.

   169             return Y.DataSchema.Base.parse.call(this, value, field);

   170         } catch (e) {

   171             Y.log('SchemaXML._getLocationValue failed: ' + e.message);

   172         }

   173 

   174         return null;

   175     },

   176 

   177     /**

   178      * Fetches the XPath-specified result for a given location in an XML node

   179      * or document.

   180      * 

   181      * @method _getXPathResult

   182      * @param locator {String} The XPath location.

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

   184      * @param xmldoc {Object} XML document to resolve namespace.

   185      * @return {Object} Data collection or null.

   186      * @static

   187      * @protected

   188      */

   189     _getXPathResult: function(locator, context, xmldoc) {

   190         // Standards mode

   191         if (! Lang.isUndefined(xmldoc.evaluate)) {

   192             return xmldoc.evaluate(locator, context, xmldoc.createNSResolver(context.ownerDocument ? context.ownerDocument.documentElement : context.documentElement), 0, null);

   193           

   194         }

   195         // IE mode

   196         else {

   197             var values=[], locatorArray = locator.split(/\b\/\b/), i=0, l=locatorArray.length, location, subloc, m, isNth;

   198             

   199             // XPath is supported

   200             try {

   201                 // this fixes the IE 5.5+ issue where childnode selectors begin at 0 instead of 1

   202                 try {

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

   204                 } catch (e) {}

   205                 

   206                 values = context.selectNodes(locator);

   207             }

   208             // Fallback for DOM nodes and fragments

   209             catch (e) {

   210                 // Iterate over each locator piece

   211                 for (; i<l && context; i++) {

   212                     location = locatorArray[i];

   213 

   214                     // grab nth child []

   215                     if ((location.indexOf("[") > -1) && (location.indexOf("]") > -1)) {

   216                         subloc = location.slice(location.indexOf("[")+1, location.indexOf("]"));

   217                         //XPath is 1-based while DOM is 0-based

   218                         subloc--;

   219                         context = context.children[subloc];

   220                         isNth = true;

   221                     }

   222                     // grab attribute value @

   223                     else if (location.indexOf("@") > -1) {

   224                         subloc = location.substr(location.indexOf("@"));

   225                         context = subloc ? context.getAttribute(subloc.replace('@', '')) : context;

   226                     }

   227                     // grab that last instance of tagName

   228                     else if (-1 < location.indexOf("//")) {

   229                         subloc = context.getElementsByTagName(location.substr(2));

   230                         context = subloc.length ? subloc[subloc.length - 1] : null;

   231                     }

   232                     // find the last matching location in children

   233                     else if (l != i + 1) {

   234                         for (m=context.childNodes.length-1; 0 <= m; m-=1) {

   235                             if (location === context.childNodes[m].tagName) {

   236                                 context = context.childNodes[m];

   237                                 m = -1;

   238                             }

   239                         }

   240                     }

   241                 }

   242                 

   243                 if (context) {

   244                     // attribute

   245                     if (Lang.isString(context)) {

   246                         values[0] = {value: context};

   247                     }

   248                     // nth child

   249                     else if (isNth) {

   250                         values[0] = {value: context.innerHTML};

   251                     }

   252                     // all children

   253                     else {

   254                         values = Y.Array(context.childNodes, 0, true);

   255                     }

   256                 }

   257             }

   258 

   259             // returning a mock-standard object for IE

   260             return {

   261                 index: 0,

   262                 

   263                 iterateNext: function() {

   264                     if (this.index >= this.values.length) {return undefined;}

   265                     var result = this.values[this.index];

   266                     this.index += 1;

   267                     return result;

   268                 },

   269 

   270                 values: values

   271             };

   272         }

   273     },

   274 

   275     /**

   276      * Schema-parsed result field.

   277      *

   278      * @method _parseField

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

   280      * @param result {Object} Required. Schema parsed data object.

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

   282      * @static

   283      * @protected

   284      */

   285     _parseField: function(field, result, context) {

   286         var key = field.key || field,

   287             parsed;

   288 

   289         if (field.schema) {

   290             parsed = { results: [], meta: {} };

   291             parsed = SchemaXML._parseResults(field.schema, context, parsed);

   292 

   293             result[key] = parsed.results;

   294         } else {

   295             result[key] = SchemaXML._getLocationValue(field, context);

   296         }

   297     },

   298 

   299     /**

   300      * Parses results data according to schema

   301      *

   302      * @method _parseMeta

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

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

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

   306      * @static

   307      * @protected

   308      */

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

   310         if(Lang.isObject(metaFields)) {

   311             var key,

   312                 xmldoc = xmldoc_in.ownerDocument || xmldoc_in;

   313 

   314             for(key in metaFields) {

   315                 if (metaFields.hasOwnProperty(key)) {

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

   317                 }

   318             }

   319         }

   320         return data_out;

   321     },

   322 

   323     /**

   324      * Schema-parsed result to add to results list.

   325      *

   326      * @method _parseResult

   327      * @param fields {Array} Required. A collection of field definition.

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

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

   330      * @static

   331      * @protected

   332      */

   333     _parseResult: function(fields, context) {

   334         var result = {}, j;

   335 

   336         // Find each field value

   337         for (j=fields.length-1; 0 <= j; j--) {

   338             SchemaXML._parseField(fields[j], result, context);

   339         }

   340 

   341         return result;

   342     },

   343 

   344     /**

   345      * Schema-parsed list of results from full data

   346      *

   347      * @method _parseResults

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

   349      * @param context {Object} XML node or document to parse.

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

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

   352      * @static

   353      * @protected

   354      */

   355     _parseResults: function(schema, context, data_out) {

   356         if (schema.resultListLocator && Lang.isArray(schema.resultFields)) {

   357             var xmldoc = context.ownerDocument || context,

   358                 fields = schema.resultFields,

   359                 results = [],

   360                 node, nodeList, i=0;

   361 

   362             if (schema.resultListLocator.match(/^[:\-\w]+$/)) {

   363                 nodeList = context.getElementsByTagName(schema.resultListLocator);

   364                 

   365                 // loop through each result node

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

   367                     results[i] = SchemaXML._parseResult(fields, nodeList[i]);

   368                 }

   369             } else {

   370                 nodeList = SchemaXML._getXPathResult(schema.resultListLocator, context, xmldoc);

   371 

   372                 // loop through the nodelist

   373                 while ((node = nodeList.iterateNext())) {

   374                     results[i] = SchemaXML._parseResult(fields, node);

   375                     i += 1;

   376                 }

   377             }

   378 

   379             if (results.length) {

   380                 data_out.results = results;

   381             } else {

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

   383             }

   384         }

   385         return data_out;

   386     }

   387 };

   388 

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

   390 

   391 

   392 }, '3.10.3', {"requires": ["dataschema-base"]});