1. Service Oriented Architecture
Deel 4 – SOA vanuit technisch perspectief
Leiden
19 May 2010
Bas Kruiswijk

2. Service Oriented Architecture
Overzicht
Deel 4: SOA vanuit technisch perspectief
1. Basisconcepten
2. SOA vanuit organisatorisch perspectief
3. Procesbesturing
4. SOA vanuit technisch perspectief
– Service als technisch concept
– Web services
5. De SOA infrastructuur
6. SOA in het ontwerpproces
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3. Service Oriented Architecture
Services
– From a technical perspective a logical next step following
object- en component technology
– Broad adoption of (internet)standards for web services
– Platform independant
– Central concept in (almost) alle current software development
platforms (for instance the Java and .NET based platforms)
Visible service interface
description
request
Service
interface
Service respons
implementation
Invisible, encapsulated
internal implementation
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4. Service Oriented Architecture
Service
Visible service interface
description
request
Service
interface
Service respons
implementation
Invisible, encapsulated
internal implementation
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5. Service Oriented Architecture
Web services
– Web services are the most common technical implementation
of a service
– Web services are not the only possible technical implementation
– Term Web services refers to a collection of standards that cover
interoperability
– Fundamental standards
– XML (eXtensible Markup Language) and XSD (XML Schema
Definition)
– HTTP (HyperText Transfer Protocol)
– WSDL (Web Service Definition Language)
– SOAP (Simple Object Access Protocol)
– UDDI (Universal Description, Discovery and Integration)
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6. Service Oriented Architecture
Fundamental standards for web services (1)
HTTP and XML (existed before web services)
Visible service interface XML
description
request
Service
interface
XML
Service respons
HTTP
implementation
Invisible, encapsulated
internal implementation
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7. Service Oriented Architecture
XML Example
<books>
– eXtensible Markup Language <book>
<author>Don Box</author>
for data-exchange, -storage <title>Essential XML</title>
and –presentation <price>34,95</price>
</book>
– General format, tag-structure <book>
<author>Linus Torvalds</author>
– Most other web services <title>Linux for Fun</title>
<price>34,95</price>
standards (and many others) </book>
are based on XML </books>
<ClientSuwi>
<SofiNr>123456789</SofiNr>
<BankGironr>01982712</BankGironr>
<TelefoonnrClient>
<Telefoonnr>
<Netnr>020</Netnr>
<Abonneenr>4890000</Abonneenr>
</Telefoonnr>
</TelefoonnrClient>
</ClientSuwi>
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8. Service Oriented Architecture
XML and XSD (XML Schema Definition)
Example
<shiporder orderid="889923"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" – An XML File has a
xsi:noNamespaceSchemaLocation="shiporder.xsd">
"shiporder.xsd"
<orderperson>John Smith</orderperson> structure
<shipto>
<name>Ola Nordmann</name> – An XML Schema
<address>Langgt 23</address> Definition (XSD)
<city>4000 Stavanger</city>
<country>Norway</country> describes this structure
</shipto>
<item>
<title>Empire Burlesque</title>
<note>Special Edition</note>
<quantity>1</quantity>
<price>10.90</price>
</item>
<item>
<title>Hide your heart</title>
<quantity>1</quantity>
<price>9.90</price>
</item>
</shiporder>
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9. Service Oriented Architecture
XML and XSD (XML Schema Definition)
<shiporder orderid="889923"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="shiporder.xsd">
"shiporder.xsd" Part of the XSD
<xs:element name="shipto">
<orderperson>John Smith</orderperson>
<xs:complexType>
<shipto>
<xs:sequence>
<name>Ola Nordmann</name>
<xs:element name="name" type="xs:string"/>
<address>Langgt 23</address>
<xs:element name="address" type="xs:string"/>
<city>4000 Stavanger</city>
<xs:element name="city" type="xs:string"/>
<country>Norway</country>
<xs:element name="country" type="xs:string"/>
</shipto>
</xs:sequence>
<item>
</xs:complexType>
<title>Empire Burlesque</title>
</xs:element>
<note>Special Edition</note>
<quantity>1</quantity>
<price>10.90</price> <xs:element name="item" maxOccurs="unbounded">
</item> <xs:complexType>
<item> <xs:sequence>
<title>Hide your heart</title> <xs:element name="title" type="xs:string"/>
<quantity>1</quantity> <xs:element name="note" type="xs:string" minOccurs="0"/>
<price>9.90</price> <xs:element name="quantity" type="xs:positiveInteger"/>
</item> <xs:element name="price" type="xs:decimal"/>
</shiporder> </xs:sequence>
XML </xs:complexType>
</xs:element>
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10. Service Oriented Architecture
XML and XSD (XML Schema Definition)
Example <?xml version="1.0" encoding="ISO-8859-1" ?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<?xml version="1.0" encoding="ISO-8859-1"?> <xs:element name="shiporder">
<xs:complexType>
<shiporder orderid="889923" <xs:sequence>
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" <xs:element name="orderperson" type="xs:string"/>
xsi:noNamespaceSchemaLocation="shiporder.xsd"> <xs:element name="shipto">
<orderperson>John Smith</orderperson> <xs:complexType>
<shipto> <xs:sequence>
<name>Ola Nordmann</name> <xs:element name="name" type="xs:string"/>
<address>Langgt 23</address> <xs:element name="address" type="xs:string"/>
<city>4000 Stavanger</city> <xs:element name="city" type="xs:string"/>
<country>Norway</country> <xs:element name="country" type="xs:string"/>
</shipto> </xs:sequence>
<item> </xs:complexType>
<title>Empire Burlesque</title> </xs:element>
<note>Special Edition</note> <xs:element name="item" maxOccurs="unbounded">
<quantity>1</quantity> <xs:complexType>
<price>10.90</price> <xs:sequence>
</item> <xs:element name="title" type="xs:string"/>
<item> <xs:element name="note" type="xs:string" minOccurs="0"/>
<title>Hide your heart</title> <xs:element name="quantity" type="xs:positiveInteger"/>
<quantity>1</quantity> <xs:element name="price" type="xs:decimal"/>
<price>9.90</price> </xs:sequence>
</item> </xs:complexType>
</shiporder> </xs:element>
Complete XML </xs:sequence>
<xs:attribute name="orderid" type="xs:string" use="required"/>
</xs:complexType>
XSD Defines the </xs:element>
structure of every XML </xs:schema>
based on it Complete XSD
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11. Service Oriented Architecture
Fundamental standards for web services (2)
WSDL
Visible service interface XML WSDL
description
request
Service
interface
XML
Service respons
HTTP
implementation
Invisible, encapsulated
internal implementation
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12. Service Oriented Architecture
WSDL
Web Service Definition Language
– Web Service Definition Language <definitions>
– Define the service interface for a <types> XSD definitions
definition of types........ used
web service
</types>
– Contains all the information needed to
Possible
call the web service <message> request and
– Signature (name and paramaters): definition of a message.... response
description of the request and response </message> messages
messages
– Protocal an location: where to find the <portType> Interfaces
service, and how to access it definition of a port....... request/
</portType> response
combinations
<binding>
definition of a binding.... How to
call it
</binding>
</definitions>
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13. Service Oriented Architecture
WSDL example
A simple Glossary
<message name="getTermRequest">
Request message <part name="term" type="xs:string"/>
</message>
<message name="getTermResponse">
Response message <part name="value" type="xs:string"/>
</message>
<portType name="glossaryTerms">
Interface <operation name="getTerm">
When you send a <input message="getTermRequest"/>
“getTermRequest” <output message="getTermResponse"/>
you get a </operation>
“getTermResponse” back </portType>
<binding type="glossaryTerms" name="b1">
<soap:binding style="document"
SOAP action
transport="http://schemas.xmlsoap.org/soap/http" />
that corresponds
<operation>
to this action
<soap:operation soapAction="http://example.com/getTerm"/>
<input><soap:body use="literal"/></input>
<output><soap:body use="literal"/></output>
</operation>
</binding>
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14. Service Oriented Architecture
Fundamental standards for web services (3)
SOAP
Visible service interface XML WSDL
description
request
SOAP
Service
interface
XML
Service respons
HTTP
implementation
Invisible, encapsulated
internal implementation
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15. Service Oriented Architecture
SOAP
Simple Object Access Protocol
– Simple Object Access Protocol <?xml version="1.0"?>
– Call a component’s service by sending <soap:Envelope
an XML-message xmlns:soap="http://www.w3.org/2001/12/soap-
– Based on standard internet technology
envelope"
(HTTP)
soap:encodingStyle="http://www.w3.org/2001/
12/soap-encoding">
– Suitable for Business-to-Business
communication: communication <soap:Header>
between dissimilar systems (often
...
outside your own company)
</soap:Header>
<soap:Body>
– Requests and Responses can be ...
sent and received as SOAP <soap:Fault>
messages ...
</soap:Fault>
</soap:Body>
</soap:Envelope>
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16. Service Oriented Architecture
A SOAP message
van
Header
aan
Beste / /
Body
Envelope
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17. Service Oriented Architecture
SOAP
Example
Request
<?xml version="1.0"?>
<soap:Envelope
xmlns:soap="http://www.w3.org/2001/12/soap-envelope"
soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding">
<soap:Body>
<m:GetPrice xmlns:m="http://www.w3schools.com/prices">
<m:Item>Apples</m:Item>
</m:GetPrice>
</soap:Body>
Response
<?xml version="1.0"?>
</soap:Envelope>
<soap:Envelope
xmlns:soap="http://www.w3.org/2001/12/soap-envelope"
soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding">
<soap:Body>
<m:GetPriceResponse xmlns:m="http://www.w3schools.com/prices">
<m:Price>1.90</m:Price>
</m:GetPriceResponse>
</soap:Body>
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18. Service Oriented Architecture
Fundamental standards for web services (4)
UDDI
Visible service interface XML WSDL
description
request
SOAP
Service
interface
XML
Service respons
HTTP
implementation
Web
Services
Invisible, encapsulated
internal implementation
Rotterdam
UDDI
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19. Service Oriented Architecture
Web services
XML message
Described by
a WSDL
van
an
a
Bes te /
definition
Inside a
/
SOAP message
Sent over
internet (HTTP
HTTP)
HTTP
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20. Service Oriented Architecture
Web services protocols
UDDI
Supporting
protocol
WSDL
SOAP
Application
XML protocol
HTTP
TCP
Transport
protocol
IP
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21. Service Oriented Architecture
Bas Kruiswijk
bkr@tg.nl
www.twynstragudde.nl
All rights reserved. No part of this presentation may be
reproduced or published in any form or by any means
without the prior written permission of Twynstra Gudde.
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