betfair-sports-api/lib/betfair_encoder.js

Betfair Sports API for Node

//(C) 2012 Anton Zemlyanov

//The module "encodes" native JavaScript objects into SOAP xml invocation requests
//see Sports API documentation on http://bdp.betfair.com

//Exported properties:
//encode   - converts native JavaScript object into Betfair SOAP XML request

var util = require('util');
var XMLWriter = require('xml-writer');

exports.encode = function(action, schema, input) {
    // Xml doc
    var doc = new XMLWriter(false);
    doc.startDocument();

    // Envelope tag
    doc.startElement('soap:Envelope');
    doc.writeAttribute('xmlns:soap', 'http://schemas.xmlsoap.org/soap/envelope/');
    doc.writeAttribute('xmlns:xsi', 'http://www.w3.org/2001/XMLSchema-instance');
    doc.writeAttribute('xmlns:xsd', 'http://www.w3.org/');
    doc.writeAttribute('xmlns:n2', 'http://www.betfair.com/publicapi/types/exchange/v5/');

    // Body tag
    doc.startElement('soap:Body');

    // action tag
    doc.startElement(action);
    doc.writeAttribute('xmlns', schema);

    // request tag
    doc.startElement('request');

    // request content (actual request data)
    encodeObject(input, doc);

    doc.endElement(); // request
    doc.endElement(); // action
    doc.endElement(); // body
    doc.endElement(); // envelope
    doc.endDocument();

    // console.log(doc.toString());
    return doc.toString();
}

function encodeObject(object, doc) {
    for ( var itemKey in object) {
        var itemVal = object[itemKey];
        // console.log(itemKey + "/" + itemVal);
        switch (typeof itemVal) {
        case 'string':
            doc.writeElement(itemKey, itemVal);
            break;
        case 'number':
            doc.writeElement(itemKey, itemVal.toString());
            break;
        case 'date':
            doc.writeElement(itemKey, itemVal.toISOString());
            break;
        case 'object':
            if (util.isArray(itemVal)) {
                // encode array
                var nm = itemVal[0];
                nm = nm.charAt(0).toUpperCase() + nm.slice(1);
                doc.startElement(itemKey);
                doc.writeAttribute('xsi:type', 'n2:ArrayOf' + nm);
                encodeArray(itemVal, doc);
                doc.endElement();
            } else {
                // encode object
                var isDate = itemVal instanceof Date;
                if (isDate) {
                    doc.writeElement(itemKey, itemVal.toISOString());
                } else {
                    doc.startElement(itemKey);
                    encodeObject(itemVal, doc);
                    doc.endElement();
                }
            }
            break;
        default:
            // console.log("unknown");
            break;
        }
    }
    return;
}

function encodeArray(array, doc) {
    // console.log("array", array);
    var itemTagName = array.shift();

    for ( var itemKey in array) {
        var itemVal = array[itemKey];
        // console.log("encodeArray: itemVal", itemVal);
        switch (typeof itemVal) {
        case 'string':
            doc.writeElement(itemTagName, itemVal);
            break;
        case 'number':
            doc.writeElement(itemTagName, itemVal.toString());
            break;
        case 'object':
            // encode object
            var isDate = itemVal instanceof Date;
            if (isDate) {
                doc.writeElement(itemTagName, itemVal.toString());
            } else {
                doc.startElement(itemTagName);
                encodeObject(itemVal, doc);
                doc.endElement();
            }
            break;
        default:
            // console.log("unknown");
            break;
        }
    }
    return;
}