/**
* Parses a SPARQL result set, assumed to be in either W3C's
* [XML](http://www.w3.org/TR/rdf-sparql-XMLres/) or
* [JSON](http://www.w3.org/TR/rdf-sparql-json-res/) format, into
* [Google
* JSON](https://developers.google.com/chart/interactive/docs/reference#DataTable)
* which is the JSON format that the
* `google.visualization.DataTable` class accepts.
*
* Variable notation: xtable, xcol(s), xrow(s) -- x is 's'(parql)
* or 'g'(oogle).
*
* Dependencies:
* - `sgvizler.namespace`
* - jQuery - for xml "browsing".
*
* @class sgvizler.parser
* @static
*/
S.parser = (function () {
/*global $ */
// Module dependencies:
var namespace = S.namespace,
/**
* Convertion table for turning XSD datatypes into the
* "javascript" datatypes which the
* `google.visualization.DataTable` accepts, which is: `string`,
* `number`, `boolean`, `date`, `datetime`, `timeofday`.
* @property datatypeXSD2JS
* @type Object
* @private
* @since 0.1
**/
datatypeXSD2JS = (function () {
var xsdns = namespace.get('xsd'),
table = [];
table[xsdns + "float"] = 'number';
table[xsdns + "decimal"] = 'number';
table[xsdns + "int"] = 'number';
table[xsdns + "integer"] = 'number';
table[xsdns + "long"] = 'number';
table[xsdns + "boolean"] = 'boolean';
table[xsdns + "date"] = 'date';
table[xsdns + "dateTime"] = 'datetime';
table[xsdns + "time"] = 'timeofday';
return table;
}()),
/**
* Converts XSD datatypes into Google JSON datatypes.
*
* See also property `datatypeXSD2JS`.
* @method getGoogleJsonDatatype
* @private
* @param {string} sdatatype An XSD datatype, full URL.
* @return {string} gdatatype, defaults to `string`
* @since 0.1
**/
getGoogleJsonDatatype = function (sdatatype) {
return datatypeXSD2JS[sdatatype] || 'string';
},
/** Converts results values into Google JSON values
* according to the Google JSON datatype, i.e., values
* other than strings and booleans need special
* treatment. If the value is an URL, we "prefixify" it.
*
* See also `sgvizler.namespace.prefixify`
*
* @method getGoogleJsonValue
* @private
* @param {string|number|boolean} value The value from the SPARQL result set.
* @param {string} gdatatype The Google JSON datatype.
* @param {string} stype The `type` of the value in the
* SPARQL endpoint, e.g. `uri` or `literal`.
* @return {Date|number|string} The converted value.
* @since 0.1
**/
getGoogleJsonValue = function (value, gdatatype, stype) {
var newvalue;
if (gdatatype === 'number') {
newvalue = Number(value);
} else if (gdatatype === 'date') {
//assume format yyyy-MM-dd
newvalue = new Date(value.substr(0, 4),
value.substr(5, 2),
value.substr(8, 2));
} else if (gdatatype === 'datetime') {
//assume format yyyy-MM-ddZHH:mm:ss
newvalue = new Date(value.substr(0, 4),
value.substr(5, 2),
value.substr(8, 2),
value.substr(11, 2),
value.substr(14, 2),
value.substr(17, 2));
} else if (gdatatype === 'timeofday') {
//assume format HH:mm:ss
newvalue = [value.substr(0, 2),
value.substr(3, 2),
value.substr(6, 2)];
} else { // datatype === 'string' || datatype === 'boolean'
if (stype === 'uri') { // replace namespace with prefix
newvalue = namespace.prefixify(value);
}
newvalue = value;
}
return newvalue;
};
///////////////////////////////////////////////////
// PUBLICs
return {
/**
* Converts a SPARQL XML result set into "Google JSON",
* see
* https://developers.google.com/chart/interactive/docs/reference#DataTable.
* @method convertXML
* @protected
* @param {Object} sxml The SPARQL XML result set.
* @return {Object} Object literal ready for
* `google.visualization.DataTable` consumption.
* @since 0.2.2
**/
convertXML: function (sxml) {
var c, clen, // column index.
r, // row index.
gcols = [],
grows = [],
gdatatype = [], // for easy reference of datatypes.
sresults = $(sxml).find('sparql').find('results').find('result');
// Build gcols: find column names and datatypes.
c = 0;
$(sxml).find('sparql').find('head').find('variable').each(function () {
var sdatatype = null,
name = $(this).attr('name'),
scell = null,
scells = $(sresults).find('binding[name="' + name + '"]');
if (scells.length) {
scell = $(scells).first().children().first()[0]; // uri, literal element
sdatatype = $(scell).attr('datatype');
}
gdatatype[c] = getGoogleJsonDatatype(sdatatype);
gcols[c] = { id: name, label: name, type: gdatatype[c] };
c += 1;
});
// Build grows: get results.
r = 0;
$(sresults).each(function () {
var gvalue,
scells,
scell,
stype,
svalue,
grow = [];
for (c = 0, clen = gcols.length; c < clen; c += 1) {
gvalue = null;
scells = $(this).find('binding[name="' + gcols[c].id + '"]');
if (scells.length &&
$(scells).first().children().first() &&
$(scells).first().children().first()[0]) {
scell = $(scells).first().children().first()[0]; // uri, literal element
stype = scell.nodeName;
svalue = $(scell).first().text();
gvalue = getGoogleJsonValue(svalue, gdatatype[c], stype);
}
grow[c] = { v: gvalue };
}
grows[r] = { c: grow };
r += 1;
});
return { cols: gcols, rows: grows };
},
/**
* Converts a SPARQL JSON result set into "Google JSON",
* see
* https://developers.google.com/chart/interactive/docs/reference#DataTable.
* @method convertJSON
* @protected
* @param {Object} stable The SPARQL JSON result set.
* @return {Object} Object literal ready for
* `google.visualization.DataTable` consumption.
* @since 0.1
**/
convertJSON: function (stable) {
var c, clen, // column index.
r, rlen, // row index.
srow,
grow,
gvalue,
sdatatype,
gcols = [],
grows = [],
gdatatype = [], // for easy reference of datatypes
scols = stable.head.vars,
srows = stable.results.bindings;
// Build gcols: find column names and datatypes.
for (c = 0, clen = scols.length; c < clen; c += 1) {
// Find a row where there is a value for this column
// in order to determine correct datatype.
r = 0;
while (r + 1 < srows.length && srows[r][scols[c]] === undefined) {
r += 1;
}
sdatatype = (srows[r] && (srows[r][scols[c]] && srows[r][scols[c]].datatype)) || null;
gdatatype[c] = getGoogleJsonDatatype(sdatatype);
gcols[c] = { id: scols[c], label: scols[c], type: gdatatype[c] };
}
// Build grows.
// loop rows
for (r = 0, rlen = srows.length; r < rlen; r += 1) {
srow = srows[r];
grow = [];
// loop cells
for (c = 0, clen = scols.length; c < clen; c += 1) {
gvalue = null;
if (srow[scols[c]] && srow[scols[c]].value) {
gvalue = getGoogleJsonValue(srow[scols[c]].value, gdatatype[c], srow[scols[c]].type);
}
grow[c] = { v: gvalue };
}
grows[r] = { c: grow };
}
return { cols: gcols, rows: grows };
},
/**
* Returns number of results, SPARQL XML.
* @method countXML
* @protected
* @param {Object} sxml The SPARQL XML result set.
* @return {number} The number of result set rows.
* @since 0.2.2
*/
countXML: function (sxml) {
return $(sxml).find('sparql').find('results').find('result').length;
},
/**
* Returns number of results, SPARQL JSON.
* @method countJSON
* @protected
* @param {Object} stable The SPARQL JSON result set.
* @return {number} The number of result set rows.
* @since 0.1
*/
countJSON: function (stable) {
return stable.results.bindings && stable.results.bindings.length;
}
};
}());
