f805ad34c19740fa0c9729ce35fe59d191912f32Luke SmithProvides a DataSchema implementation which can be used to work with XML data.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith@module dataschema
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith@submodule dataschema-xml
f805ad34c19740fa0c9729ce35fe59d191912f32Luke SmithProvides a DataSchema implementation which can be used to work with XML data.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke SmithSee the `apply` method for usage.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith@extends DataSchema.Base
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith ////////////////////////////////////////////////////////////////////////////
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // DataSchema.XML static methods
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith ////////////////////////////////////////////////////////////////////////////
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith Applies a schema to an XML data tree, returning a normalized object with
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith results in the `results` property. Additional information can be parsed out
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith of the XML for inclusion in the `meta` property of the response object. If
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith an error is encountered during processing, an `error` property will be
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith Field data in the nodes captured by the XPath in _schema.resultListLocator_
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith is extracted with the field identifiers described in _schema.resultFields_.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith Field identifiers are objects with the following properties:
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * `key` : <strong>(required)</strong> The desired property name to use
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith store the retrieved value in the result object. If `locator` is
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith not specified, `key` is also used as the XPath locator (String)
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * `locator`: The XPath locator to the node or attribute within each
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith result node found by _schema.resultListLocator_ containing the
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith desired field data (String)
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * `parser` : A function or the name of a function on `Y.Parsers` used
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith to convert the input value into a normalized type. Parser
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith functions are passed the value as input and are expected to
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith return a value.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * `schema` : Used to retrieve nested field data into an array for
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith assignment as the result field value. This object follows the same
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith conventions as _schema_.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith If no value parsing or nested parsing is needed, you can use XPath locators
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith (strings) instead of field identifiers (objects) -- see example below.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith `response.results` will contain an array of objects with key:value pairs.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith The keys are the field identifier `key`s, and the values are the data
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith values extracted from the nodes or attributes found by the field `locator`
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith (or `key` fallback).
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith To extract additional information from the XML, include an array of
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith XPath locators in _schema.metaFields_. The collected values will be
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith stored in `response.meta` with the XPath locator as keys.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith var schema = {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith resultListLocator: '//produce/item',
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith resultFields: [
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith locator: 'name',
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith locator: 'color',
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith key: 'color',
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith parser: function (val) { return val.toUpperCase(); }
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // Assumes data like
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // <inventory>
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // <produce>
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // <item><name>Banana</name><color>yellow</color></item>
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // <item><name>Orange</name><color>orange</color></item>
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // <item><name>Eggplant</name><color>purple</color></item>
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // </produce>
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // </inventory>
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith var response = Y.DataSchema.JSON.apply(schema, data);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // response.results[0] is { name: "Banana", color: "YELLOW" }
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith @method apply
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith @param {Object} schema Schema to apply. Supported configuration
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith properties are:
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith @param {String} [schema.resultListLocator] XPath locator for the
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith XML nodes that contain the data to flatten into `response.results`
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith @param {Array} [schema.resultFields] Field identifiers to
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith locate/assign values in the response records. See above for
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith @param {Array} [schema.metaFields] XPath locators to extract extra
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith non-record related information from the XML data
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith @param {XMLDoc} data XML data to parse
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith @return {Object} An Object with properties `results` and `meta`
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith if (xmldoc && okNodeType[xmldoc.nodeType] && schema) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // Parse results data
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith data_out = SchemaXML._parseResults(schema, xmldoc, data_out);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // Parse meta data
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith data_out = SchemaXML._parseMeta(schema.metaFields, xmldoc, data_out);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith Y.log("XML data could not be schema-parsed: " + Y.dump(data) + " " + Y.dump(data), "error", "dataschema-xml");
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith data_out.error = new Error("XML schema parse failure");
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * Get an XPath-specified value for a given field from an XML node or document.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @method _getLocationValue
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param field {String | Object} Field definition.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param context {Object} XML node or document to search within.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @return {Object} Data value or null.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @protected
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith var locator = field.locator || field.key || field,
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith result = SchemaXML._getXPathResult(locator, context, xmldoc);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith value = res.textContent || res.value || res.text || res.innerHTML || null;
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // FIXME: Why defer to a method that is mixed into this object?
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // DSchema.Base is mixed into DSchema.XML (et al), so
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // DSchema.XML.parse(...) will work. This supports the use case
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // where DSchema.Base.parse is changed, and that change is then
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // seen by all DSchema.* implementations, but does not support the
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // case where redefining DSchema.XML.parse changes behavior. In
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // fact, DSchema.XML.parse is never even called.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith return Y.DataSchema.Base.parse.call(this, value, field);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith } catch (e) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith Y.log('SchemaXML._getLocationValue failed: ' + e.message);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith return null;
b3558e978532e4905c7b41b2d0821948ac047dbbLuke Smith * Fetches the XPath-specified result for a given location in an XML node
b3558e978532e4905c7b41b2d0821948ac047dbbLuke Smith * or document.
b3558e978532e4905c7b41b2d0821948ac047dbbLuke Smith * @method _getXPathResult
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param locator {String} The XPath location.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param context {Object} XML node or document to search within.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param xmldoc {Object} XML document to resolve namespace.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @return {Object} Data collection or null.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @protected
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith _getXPathResult: function(locator, context, xmldoc) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // Standards mode
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith return xmldoc.evaluate(locator, context, xmldoc.createNSResolver(context.ownerDocument ? context.ownerDocument.documentElement : context.documentElement), 0, null);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith var values=[], locatorArray = locator.split(/\b\/\b/), i=0, l=locatorArray.length, location, subloc, m, isNth;
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // XPath is supported
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // this fixes the IE 5.5+ issue where childnode selectors begin at 0 instead of 1
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith xmldoc.setProperty("SelectionLanguage", "XPath");
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // Fallback for DOM nodes and fragments
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // Iterate over each locator piece
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith for (; i<l && context; i++) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // grab nth child []
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith if ((location.indexOf("[") > -1) && (location.indexOf("]") > -1)) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith subloc = location.slice(location.indexOf("[")+1, location.indexOf("]"));
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith //XPath is 1-based while DOM is 0-based
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // grab attribute value @
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith context = subloc ? context.getAttribute(subloc.replace('@', '')) : context;
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // grab that last instance of tagName
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith subloc = context.getElementsByTagName(location.substr(2));
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith context = subloc.length ? subloc[subloc.length - 1] : null;
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // find the last matching location in children
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith else if (l != i + 1) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith for (m=context.childNodes.length-1; 0 <= m; m-=1) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith if (location === context.childNodes[m].tagName) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // attribute
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // nth child
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // all children
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // returning a mock-standard object for IE
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith if (this.index >= this.values.length) {return undefined;}
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * Schema-parsed result field.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @method _parseField
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param field {String | Object} Required. Field definition.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param result {Object} Required. Schema parsed data object.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param context {Object} Required. XML node or document to search within.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @protected
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith parsed = SchemaXML._parseResults(field.schema, context, parsed);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith result[key] = SchemaXML._getLocationValue(field, context);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * Parses results data according to schema
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @method _parseMeta
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param xmldoc_in {Object} XML document parse.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param data_out {Object} In-progress schema-parsed data to update.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @return {Object} Schema-parsed data.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @protected
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith _parseMeta: function(metaFields, xmldoc_in, data_out) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith data_out.meta[key] = SchemaXML._getLocationValue(metaFields[key], xmldoc);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * Schema-parsed result to add to results list.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @method _parseResult
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param fields {Array} Required. A collection of field definition.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param context {Object} Required. XML node or document to search within.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @return {Object} Schema-parsed data.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @protected
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith var result = {}, j;
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // Find each field value
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith SchemaXML._parseField(fields[j], result, context);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * Schema-parsed list of results from full data
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @method _parseResults
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param schema {Object} Schema to parse against.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param context {Object} XML node or document to parse.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @param data_out {Object} In-progress schema-parsed data to update.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @return {Object} Schema-parsed data.
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith * @protected
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith _parseResults: function(schema, context, data_out) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith if (schema.resultListLocator && Lang.isArray(schema.resultFields)) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith if (schema.resultListLocator.match(/^[:\-\w]+$/)) {
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith nodeList = context.getElementsByTagName(schema.resultListLocator);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // loop through each result node
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith results[i] = SchemaXML._parseResult(fields, nodeList[i]);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith nodeList = SchemaXML._getXPathResult(schema.resultListLocator, context, xmldoc);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith // loop through the nodelist
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith results[i] = SchemaXML._parseResult(fields, node);
f805ad34c19740fa0c9729ce35fe59d191912f32Luke Smith data_out.error = new Error("XML schema result nodes retrieval failure");