jinujoseph79/countrydetails_springsoap

SOAP web services using spring boot

Project

CountryDetails_SpringSOAP is a sample project for SOAP web services. SOAP is a messaging protocol. Messages (requests and responses) are XML documents over HTTP. The XML contract is defined by the WSDL (Web Services Description Language). It provides a set of rules to define the messages, bindings, operations, and location of the service.

There are two possible approaches when creating a web service: Contract-Last and Contract-First. Here contract-first is used and we start with the WSDL contract, from which we generate the Java classes.

There is also a Spring client to invoke and test the above web service.The service might be deployed anywhere in the world, and with just its WSDL, we were able to generate the same classes at the client end as the server!

Getting Started

This repository contains the code for the CountryDetails application. The code can be cloned to local directory.

Dependencies: spring-boot-starter-web spring-boot-starter-web-services wsdl4j dependencies

Here we re using contract-first approach. In this we have to create the domain (methods and parameters) for our service first. We use an XML schema file (XSD), countres.xsd that Spring-WS will export automatically as a WSDL.

In XSD file we define getCountryRequest web service request which accepts one parameter of type string. We also define the format of the response, which contains an object of the type country. Then we have country and currency objects. Currency object is used within country object.

From the XSD file, jaxb2-maven-plugin will automatically generate the Java code. The plugin uses the XJC tool as code generation engine. Then we need to add SOAP web service end points. The SOAP web service endpoint class will handle all the incoming requests for the service. It will initiate the processing and will send the response back. Create a class for configuring the Spring message dispatcher servlet to receive the request and use @EnableWs to enable SOAP Web Service features in this Spring Boot application.

We will use the WSDL to generate the client code. We need to extend Spring's WebServiceGatewaySupport to interact with the web service. In the client we need to configure 2 beans:Jaxb2Marshaller to convert messages to and from XML and our CountryClient which will wire in the marshaller bean. Then Junit is used to test the client.

Features

CountryDetails application is implementing SOAP web services with spring boot. Countries.xsd file is used to create the Java classes. jaxb2-maven-plugin helps to generate the java code.The plugin uses the XJC tool as code generation engine. XJC compiles the XSD schema file into fully annotated Java classes. Four additional classes added are:

CountryEndpoint – the endpoint that replies to the request CountryRepository – the repository at the backend to supply country data WebServiceConfig – the configuration defining the required beans SpringSoapApplicationn – the Spring Boot App to make our service available for consumption

When country name is passed as request, country details is returned in response

WSDL is used to define the structure of requests and responses. http://localhost:8080/ws/countries.wsdl.

Testing

Launch the WSDL URL http://localhost:8080/ws/countries.wsdl.

To test install Wizdler in chrome. After installing Wizdler,launch the WSDL URL, http://localhost:8080/ws/students.wsdl. We will see a small icon at the corner of the Chrome browser, which you can click to see the services that are part of the WSDL. Go ahead and click the Wizdler icon and click the service getCounrty. Pass the country name and then response will have counrty details.

Junit test - In ClientLiveTest we wired in the CountryClient bean defined in our CountryClientConfig. Then, we used its getCountry to invoke the remote service. The counrty details is then asserted.

Technology used

spring-boot-starter-web-services- SOAP services

wsdl4j -The Web Services Description Language for Java Toolkit (WSDL4J) allows the creation, representation, and manipulation of WSDL documents.

Java API for XML Binding (JAXB) and Configuring a JAXB 2 Maven Plugin -We do the mapping from XML to Java and Java to XML. This is done using JAXB — a Java API for XML binding. A Maven JAXB Plugin helps us in generating the Java objects based on the XSD.

Jaxb2Marshaller -to set either the "contextPath" or the "classesToBeBound" property on this bean, possibly customize the marshaller and unmarshaller by setting properties, schemas, adapters, and listeners, and to refer to it.

Environment

Operation System: Windows 10

Java Version: Java 8