Web Services & UDDI
• Web services are distributed components that communicate
using standard protocols such as Simple Object Access
Protocol (SOAP) and HTTP.
• Web services exposes callable API functions, better known
as Web Methods over the Internet.
Web services publish details of their interface using XML
vocabulary called Web Services Description Language(WSDL).
• WSDL describes the interface for the Web service.
• WSDL is an XML-based vocabulary that describes the set
of SOAP messages that a Web service supports.
• Every Web service has an associated WSDL file that
documents the Web methods including their arguments
and return types.
• Generates a proxy class that can be used by the Web
service consumers for communicating with the Web
service.
• .NET also provides a default service description screen that
summarizes the WSDL information in a readable format.
• Automatic generation of XML based WSDL.
•Avoids handling SOAP responses and requests.
•The proxy class assembles the requests and responses
in the correct format.
•Web services are stateless.
•Web services are platform and language agnostic.
• Universal Description, Discovery and Integration (UDDI)
is a specification for building distributed databases that
enable interested parties to “discover” each other’s
Web services.
• Provides easy discovery, sharing, and reuse of Web
services and other programmable resources.
In step 1 , “Invocation Pattern using the UDDI Registry” it is shown how a
business publishes services to the UDDI registry.
In step 2, a client looks up the service in the registry and receives service
binding information.
Finally in step 3, the client then uses the binding information to invoke the
service. The UDDI APIs are SOAP based for interoperability reasons.
Here, three APIs specified in the UDDI v3 specification, Security, Publication
and Inquiry, are used.
APIs defined by UDDI:
• UDDI_Security_PortType, defines the API to obtain a security token. With a valid security token a
publisher can publish to the registry. A security token can be used for the entire session.
• UDDI_Publication_PortType, defines the API to publish business and service information to the UDDI
registry.
• UDDI_Inquiry_PortType, defines the API to query the UDDI registry. Typically this API does not
require a security token.
• UDDI_CustodyTransfer_PortType, this API can be used to transfer the custody of a business from
one UDDI node to another.
• UDDI_Subscription_PortType, defines the API to register for updates on a particular business of
service.
• UDDI_SubscriptionListener_PortType, defines the API a client must implement to receive
subscription notifications from a UDDI node.
• UDDI_Replication_PortType, defines the API to replicate registry data between UDDI nodes.
• UDDI_ValueSetValidation_PortType, by nodes to allow external providers of value set validation. Web
services to assess whether keyedReferences or keyedReferenceGroups are valid.
• UDDI_ValueSetCaching_PortType, UDDI nodes may perform validation of publisher references
themselves using the cached values obtained from such a Web service.
Conceptually, a business can register three types of information into a UDDI registry. The
specification does not call out these types specifically, but they provide a good summary of
what UDDI can store for a business:
White pages---Basic contact information and identifiers about a company, including business
name, address, contact information, and unique identifiers such as D-U-N-S numbers or tax
IDs. This information allows others to discover your web service based upon your business
identification.
Yellow pages---Information that describes a web service using different categorizations
(taxonomies). This information allows others to discover your web service based upon its
categorization (such as being in the manufacturing or car sales business).
Green pages---Technical information that describes the behaviors and supported functions of
a web service hosted by your business. This information includes pointers to the grouping
information of web services and where the web services are located.
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The Universal Description, Discovery and Integration (UDDI) protocol is one
of the major building blocks required for successful Web services.
UDDI creates a standard interoperable platform that enables companies and
applications to quickly, easily, and dynamically find and use Web services
over the Internet (or Intranet).
UDDI also allows operational registries to be maintained for different
purposes in different contexts.
UDDI is a cross-industry effort driven by major platform and software
providers, as well as marketplace operators and e-business leaders within
the OASIS standards consortium
UDDI is a Web-based distributed directory that enables businesses to list
themselves on the Internet (or Intranet) and discover each other, similar to
a traditional phone book’s yellow and white pages.
The UDDI registry is both a white pages business directory and a technical
specifications library. The Registry is designed to store information about
Businesses and Services and it holds references to detailed documentation.
• UDDI sites publish a pair of SOAP-based APIs :
Inquiry API
Publisher API .
•UDDI services enables companies to run their own
private UDDI service for use on the corporate
intranet or extranet.
•UDDI Services helps companies organize and
catalog programmatic resources.
• The four core entities that you need to model when
developing UDDI services are:

Provide
•
Service
•
Binding
•
tModel
Provider: Information about the
entity who offers a service
tModel: Descriptions of
specifications for services.
0…n
Service: Descriptive information
about a particular family of
technical offerings
0…n
Binding: Technical information
about a service entry point
Bindings contains
references to tModels.
These references declare
the interface specifications
for a service.
0…n
Microsoft.Uddi.Inquire.Url = url;
Microsoft.Uddi.Inquire.AuthenticationMode =
Microsoft.Uddi.AuthenticationMode.UddiAuthentication;
FindService fs = new FindService();
if (businessKey != String.Empty)
Microsoft.Uddi.Inquire.Url = url;
Microsoft.Uddi.Inquire.AuthenticationMode =
Microsoft.Uddi.AuthenticationMode.UddiAuthentication;
fs.BusinessKey = businessKey;
fs.FindQualifiers = _qualifiers;
if (_tTModelKeys.Count > 0)
fs.TModelKeys = _tTModelKeys;
String temp = service == String.Empty ? "%" : service;
fs.Names.Add(temp.Trim());
try
{
ServiceList svlist = fs.Send();
if (svlist == null)
return null;
List<SVInfo> list = new List<SVInfo>();
foreach (ServiceInfo si in svlist.ServiceInfos)
{
SVInfo s;
s.name = si.Name;
s.key = si.ServiceKey;
s.businesskey = si.BusinessKey;
GetBusinessDetail gbd = new GetBusinessDetail();
gbd.BusinessKeys.Add(si.BusinessKey);
BusinessDetail be = gbd.Send();
s.businessname = be.BusinessEntities[0].Names[0].Text;
GetServiceDetail gsd = new GetServiceDetail();
gsd.ServiceKeys.Add(si.ServiceKey);
ServiceDetail sd = gsd.Send();
s.accesspoint = sd.BusinessServices[0].BindingTemplates[0].AccessPoint.Text;
list.Add(s);
}
return list;
}
catch (Exception)
{
return null;
throw;
}
http://www.codeproject.com/Articles/34187/Publish-a-WSDL-to-aUDDI-Server