Distributed Systems COMP3211 - Coursework 2
Deadline: 10.00, Friday 15 November 2019
Introduction
This exercise aims to give you some practical experience of writing server and clients to
deploy and consume Web Services.
Useful Resources
• Web Services examples: available on COMP3211 area onMinerva
• Documentation for Jersey http://jersey.java.net
• Oracle Building Web Services with JAX-WS http://docs.oracle.com/javaee/6/
tutorial/doc/bnayl.html
• Oracle Building Web Services with JAX-RS https://docs.oracle.com/javaee/6/
tutorial/doc/giepu.html
• Servlets and JSP examples if you choose to develop the full, Web-based user
interface to your application http://www.minerva.leeds.ac.uk
The Task
1. Your main task is to build a Web Services client that integrates up to three Web
services. The Web services are:
• existing SOAP-based services;

• existing RESTful services, e.g. Google, Amazon, Twitter, or other public directories; 

• your own SOAP-based service which you need to develop, e.g. using JAX-WS; 

• your own RESTful service which you need to develop, e.g. using Jersey or Flask-
RESTful; • a combination of the above.
Note: The composition involves a minimum of TWO Web services and a maximum of
THREE. One of the Web services must be YOUR own and needs to be developed from
scratch, i.e a proper server with a client to test it is functional. More marks will be
allocated if you consider three Web services.
Here are two imaginary examples:
Example 1: Quote of the Day. The 1st service returns the name of an author which the
integrated client should then use to do a search on the author using the 2nd service and
output the top results/links for that author.
Example 2: Shakespeare. The client would need to get the partial text of a speech from
the user and pass it to the 1st service. It will then need to extract the name of the play or
name of the speaker from the result and use these data to construct another search query
to the 2nd Web service.
Feel free to investigate the use of Web services provided on:
• https://developers.google.com/ 

• https://aws.amazon.com/ 

• https://developer.twitter.com/ 

• http://www.programmableweb.com 

• http://mymemory.translated.net/doc/spec.php • https://flask-restful.readthedocs.io/
As you need to choose your own services, look at the services that you may find
interesting, taking note of the implementation platform and examining the WSDL or
REST API for each service.
Note that the order of difficulty varies. Some services are easy to handle because results
are returned as simple strings of plain text; others are slightly more challenging because
the returned string is XML or JSON rather than plain text (albeit simple XML/JSON),
therefore requires parsing. Some service providers e.g. Google, Twitter, Amazon) require
users to be registered for authentication and authorisation purpose (an authentication key
is usually provided after registration).
There are various ways to develop your own services. The steps to follow to write server
and client-side code are provided on Minerva.
More marks are available if you tackle original and challenging services.