How to consume MTOM SOAP web service in node.js?

Question

I need to download or process a file from a soap based web service in node.js. can someone suggest me on how to handle this in node.js

I tried with 'node-soap' or 'soap' NPM module. it worked for normal soap web service. But, not for binary steam or MTOM based SOAP web service

Answer 1

I want to try to answer this... It's quite interesting that 2 years and 2 months later I can not figure it out how to easily solve the same problem.

I'm trying to get the attachment from a response like:

...

headers: { 'cache-control': 'no-cache="set-cookie"', 'content-type': 'multipart/related;boundary="----=_Part_61_425861994.1525782562904";type="application/xop+xml";start="";start-info="text/xml"',

...

body: '------=_Part_61_425861994.1525782562904\r\nContent-Type: application/xop+xml; charset=utf-8; type="text/xml"\r\nContent-Transfer-Encoding: 8bit\r\nContent-ID: \r\n\r\n....\r\n------=_Part_61_425861994.1525782562904\r\nContent-Type: application/octet-stream\r\nContent-Transfer-Encoding: binary\r\nContent-ID: \r\n\r\n�PNG\r\n\u001a\n\u0000\u0000\u0000\rIHDR\u0000\u0000\u0002,\u0000\u0000\u0005�\b\u0006\u0........binary....

I tried ws.js but no solution.

My solution:

var request = require("request");
var bsplit = require('buffer-split')

// it will extract "----=_Part_61_425861994.1525782562904" from the response
function getBoundaryFromResponse(response) {
    var contentType = response.headers['content-type']
    if (contentType && contentType.indexOf('boundary=') != -1 ) {
        return contentType.split(';')[1].replace('boundary=','').slice(1, -1)
    }
    return null
}


function splitBufferWithPattern(binaryData, boundary) {
    var b = new Buffer(binaryData),
        delim = new Buffer(boundary),
        result = bsplit(b, delim);
    return result
}


var options = {
    method: 'POST',
    url: 'http://bla.blabal.../file',
    gzip: true,
    headers: {
        SOAPAction: 'downloadFile',
        'Content-Type': 'text/xml;charset=UTF-8'
    },
    body: '<soapenv: ... xml request of the file ... elope>'
};

var data = [];
var buffer = null;
var filename = "test.png"

request(options, function (error, response, body) {
        if (error) throw new Error(error);

        if (filename && buffer) {
            console.log("filename: " + filename)
            console.log(buffer.toString('base64'))
            // after this, we can save the file from base64 ...
        }
    })
    .on('data', function (chunk) {
        data.push(chunk)

    })
    .on('end', function () {
        var onlyPayload = splitBufferWithPattern(Buffer.concat(data), '\r\n\r\n') // this will get from PNG
        buffer = onlyPayload[2]
        buffer = splitBufferWithPattern(buffer, '\r\n-')[0]
        console.log('Downloaded.');

    })

I am not sure it will works in most of the cases. It looks like unstable code to my eyes and so I'm looking for something better.

Answer 2

Use ws.js

Here is how to fetch the file attachments:

const ws = require('ws.js')
const { Http, Mtom } = ws

var handlers =  [ new Mtom(), new Http()];
var request = '<s:Envelope xmlns:s="http://www.w3.org/2003/05/soap-envelope">' +
                '<s:Body>' +
                  '<EchoFiles xmlns="http://tempuri.org/">' +
                      '<File1 />' +
                  '</EchoFiles>' +
                '</s:Body>' +
              '</s:Envelope>'

var ctx = { request: request
          , contentType: "application/soap+xml"
          , url: "http://localhost:7171/Service/mtom"
          , action: "http://tempuri.org/IService/EchoFiles"
          }

ws.send(handlers, ctx, function(ctx) {
  //read an attachment from the soap response
  var file = ws.getAttachment(ctx, "response", "//*[local-name(.)='File1']")
  // work with the file
  fs.writeFileSync("result.jpg", file)
})

Two limitations:

• No basic auth provided out-of-box, patch required https://github.com/yaronn/ws.js/pull/40
• If the file name is an url, you need to apply another patch at mtom.js. Replace:

.

xpath = "//*[@href='cid:" + encodeURIComponent(id) + "']//parent::*"

with:

xpath = "//*[@href='cid:" + id + "']//parent::*"