Chapter 3 Service Endpoint Design

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built when the service interface definition and implementation are already 

known to it, even though this information was found dynamically.

  Scenario 3: The service implements an interface at a well known location, or 

it expects its clients to use tools to find the interface at build time. Since the 

Web service's clients are generic clients they are not clients designed solely 

to use this Web service you must design the service so that it can be regis 

tered in a registry. Such generic clients dynamically find a service's specific 

implementation at runtime using registries. Choose the type of registry for the 

service either public, corporate, or private depending on the types of its cli 

ents either general public or intra enterprise its security constraints, and so 

forth.

Table 3.2

Discovery Binding Scenarios for Clients

Scena

Discover Service 

Discover Service 

Binding to Specific 

rios

Interface Definition

Implementation

Location

1

None

None

Static

2

None or dynamic at 

Dynamic at build time

Static 

build time

3

None or dynamic at 

Dynamic at runtime

Dynamic at build time

build time

3.7

Handling XML Documents in a Web Service

Up to now, this chapter addressed issues applicable to all Web service implementa 

tions. There are additional considerations when a Web service implementation

expects to receive an XML document containing all the information from a client,

and which the service uses to start a business process to handle the request. There

are several reasons why it is appropriate to exchange documents:

  Documents, especially business documents, may be very large, and as such, 

they are often sent as a batch of related information. They may be compressed 

independently from the SOAP message. 

  Documents may be legally binding business documents. At a minimum, their 

original form needs to be conserved through the exchange and, more than like 

ly, they may need to be archived and kept as evidence in case of disagreement.