Converting Soap UI To REST Using Flask

Photo by Artturi Jalli on Unsplash

For the past few months I have been working on a project which required me to convert Soap UI which was using XML format to REST which was to use JSON as it had to be consumed on a mobile application.

What is SOAP

I know a lot of people are familiar with REST, me being one of them. It was not until I undertook this project that I came to hear of SOAP for the first time.

SOAP stands for Simple Object Access Protocol. It is a protocol follows a strict standard to allow communication between the client and the server.It also uses XML for exchanging information.

Many may wonder why we were using SOAP in the first place ? It was because the data which was required was coming from Microsoft Dynamics ERP called Navision and its standard was SOAP.

You can read the difference between SOAP and REST here

Why I Chose Flask

I chose flask and not any other framework such as django because first I relatively had a better understanding of It and also Flask is light weight and what I wanted was just a third party or an interface between the Navison ERP system and the mobile application and flask was up to the task.

Setting Up Flask

Flask is one of the easiest framework to setup in python

Create a virtual environment

python -m venv <myproject>

Activate the virtual environment

source myproject/bin/activate

Installing flask

pip3 install Flask

Those on python 2.7 can use pip

We also have to install ZEEP a python package which is a SOAP client and which will be doing the conversion from XML to Json

pip3 install zeep

The system was using NTLM for authentication and I know alot of “tech bros” have a lot to say about how NTLM is insecure but “it is what it is”

In order to use NTLM i installed requests_ntlm a python package which was to help me with NTLM authentication

pip3 install requests-ntlm

I also installed requests which was to help me make https requests

pip3 install requests

And we are done those are all the packages that we will require for this project.

NTLM Authentication

Import all the module in the main.py file.

from flask import Flask, request, jsonify
from zeep import Client
from zeep.transports import Transport
import requests
from requests_ntlm import HttpNtlmAuth

For authentication we are going to use requests and requests_ntlm

session = requests.Session()
session.auth = (HttpNtlmAuth(
    'Username', 'Password'))

The session is to ensure that we stay logged in and don’t have to login each and every time

Setting Up The Client

We need a client which will be able to recieve the XML data for conversion

url = <url>
client = Client(url,
                transport=Transport(session=session))

We provide the url to our navision system and our transport will be our session.

Making SOAP to JSON Conversion

We first need to create a flask variable

app = Flask(_name_)

We make a flask get request to the system

@app.route('/api/booklist', methods=["GET"])
def booklist():
    return client.service.bookList()

The client has a service attribute. In the service attribute we will tap into the soap function or navison function bookList() which will list all books in the system as json

In some cases the navision function may have a set of parameters that should be passed into it.

@app.route('/api/book/<bookid>')
def bookdetail(bookid):
    data = {
        "bookId": bookid
    }
    return client.service.FnBookDetails(**data).return_value

In this case the bookId is a required parameter for the FnBookDetails() function.

You can also make post requests

@app.route('/api/addBook', methods=["POST"])
def returnRecieve():
    req = request.args
    req_dict = req.to_dict()

    data = {
        "bookNo": req_dict['bookNo'],
        "bookName": req_dict['bookName'],
        "ISBN": req_dict['ISBN'],
        "publishedDate": req_dict['publishedDate'],
    }

    return client.service.FnReturnReceiveParts(**data).return_value

And it is that simple.

And it is that easy to make a SOAP to JSON conversion 🎉🎉🎉

Happy hacking 🥳.

You can reach out to me on twitter or github