Introduction to web Services Development using webMethods 

Introduction

The purpose of this Article is to describe webMethods’ position on web services and using webMethods software to develop web Services. 

What Is a Web Service?

Web services ‐ Exposing a service or functionality on a server, such as a complete order management system, you could create a Web service that maps to many different IS flow services, each performing a separate order management function and other client application on a remote server can invoke the webservice(order management system) without knowing about how the service is implemented.

Using webMethods Software to Create, Publish, and Invoke Web Services:

You can use webMethods Integration Server and webMethods Developer to create Web services, publish Web services to a UDDI registry, and invoke Web services located on remote servers.

Using webMethods Software to Create Web Services:

You can turn any service in any Integration Server package into a Web service. Integration Server provides an environment for executing services efficiently and securely. It receives and decodes requests from clients, calls the requested services, and encodes and returns the output to the clients. Integration Server also provides an extensive library of built - in services. Developer is the integrated development environment (IDE) that you use to create services on Integration Server.

Integration Server’s service ‐ oriented architecture makes it ideal for use in integration scenarios because it separates implementation from presentation. When a client application wants to invoke a Web service, the client need know only the service’s name, inputs, and outputs(signature). The client does not need to know how the service is implemented (for example, in Java or C) or what kind of back ‐ end system it accesses. Similarly, the Web service implementation (that is, the back ‐end business logic) does not need to know what kind of client invoked it. A client can use HTTP/HTTPS, FTP, or SMTP to invoke the same service. You do not need to have multiple versions of the same service because the webMethods content handler layer takes care of all marshalling and unmarshalling between the protocol layer and the implementation layer.

Web Services Developer’s Guide Version 7.1.1 13  Concepts Integration Server’s service-oriented architecture With webMethods software, you can create Web services using programming languages such as Java, C, or COM. You can also create Web services from existing back ‐end systems, without producing custom code or reconfiguring the back ‐end systems, using webMethods adapters.


Using webMethods Software to Publish Web Services to a UDDI Registry:

You can use webMethods Developer to incorporate Web services development into your integration solution. Developer enables you to create Web services from existing IS services and publish them to a UDDI registry. For more information about Web services and the UDDI Registry, see Chapter 4, “Publishing IS Services to a UDDI Registry as a Web Service” on page 55. 

Using webMethods Software to Invoke Web Services:
You can use webMethods Integration Server and webMethods Developer to invoke Web services located on remote servers. To do so, you first generate a consumer Web service descriptor “What Are Web Service Descriptors and Connectors?” on page 13. For more information about using Web services in Developer, see “Invoking a Web Service From Developer” on page 30.

What Are Web Service Descriptors and Connectors?

A Web service descriptor (WSD) is an IS element that defines a Web service in IS terms. The Web service descriptor contains all the information required by the provider or the consumer (requester) of a Web service. A provider Web service descriptor defines a Web service that is hosted on the Integration Server, that is, a service “provided” to external users. A provider Web service descriptor will expose one or more IS services as operations, which can be published to a registry as a single Web service. External users can access the Web service through the registry and
invoke the IS services remotely.