1. SOAP : Simple Object Access Protocol
Dr. Yuhong Yan
NRC-IIT-Fredericton
Internet logic

2. Service Oriented Architecture (SOA)/Web Service triangle
UDDI
Services
The correlation of SOA and Web services
The principle of SOA/Web services
The benefit of SOA/Web services
The bridge between IT implementation and business development.
WSDL
SOAP
From “Web Services Architecture W3C Working Draft”

3. Transport HTTP, SMTP, FTP, BEEP XML messaging XML-RPC, SOAP, XML
Web Service Stack
Process BPEL4WS, WSCI, WS-CDL
Discovery UDDI
Transport HTTP, SMTP, FTP, BEEP
Description WSDL
XML messaging XML-RPC, SOAP, XML
Services
Many, many more specification
interoperabilities

4. SOAP (Simple Object Access Protocol)
SOAP is a lightweight protocol for exchange of information in a decentralized, distributed environment. It is an XML based protocol that consists of three parts: an envelope that defines a framework for describing what is in a message and how to process it, a set of encoding rules for expressing instances of application-defined data types, and a convention for representing remote procedure calls and responses.

5. Look into a SOAP message
<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv=" xmlns:xsd=" xmlns:xsi="
<soapenv:Body>
<ns1:getQuote soapenv:encodingStyle=" xmlns:ns1="urn:xmltoday-delayed-quotes">
<symbol xsi:type="xsd:string">XXX</symbol>
</ns1:getQuote>
</soapenv:Body>
</soapenv:Envelope>

6. Response SOAP message
<soapenv:Envelope xmlns:soapenv=" xmlns:xsd=" xmlns:xsi="
<soapenv:Body>
<ns1:getQuoteResponse soapenv:encodingStyle=" xmlns:ns1="urn:xmltoday-delayed-quotes">
<ns1:getQuoteReturn href="#id0"/>
</ns1:getQuoteResponse>
<multiRef id="id0" soapenc:root="0" soapenv:encodingStyle=" xsi:type="xsd:float" xmlns:soapenc="
</soapenv:Body>
</soapenv:Envelope>

7. Inside SOAP P53, figure 3-2 SOAP message Envelope (required)
Header (optional)
Body (required)
Fault (optional)
P53, figure 3-2

8. Why SOAP
Inter-application communication between systems written in arbitrary languages, across the Internet.
An XML-based protocol for exchanging messages over Internet transport protocols, like HTTP, SMTP, FTP, etc.
SOAP is platform-independent.

9. Apache SOAP architecture4
Service: HelloService.java
sayHello(“Yuhong”, “Yan”)
“Yuhong Yan, Welcome to SOAP…” 3
SOAP client: HelloClient.java
AXIS SOAP engine
rpcrouter servlet 1
SOAP request: Service name: urn:HelloWorld Method name: sayHello Parameter: firstName=“Yuhong”
lastName=“Yan” 2
Jakarta Tomcat server 5
SOAP response:
Return value: “Yuhong Yan,
welcome to SOAP”
Http POST
Http GET
p69,. Fig 4-3

10. Anatomy of HelloWorld Server side code Client side code SOAP request
SOAP response

11. HelloWorldService.java package samples.HelloWorld;
public class HelloWorldService {
public String sayHello(String firstName, String lastName) throws Exception
String aString = firstName + “ " + lastName + ", welcome to SOAP Web Service World!";
return aString; }
public String addString(String symbol, String dataType) throws Exception
String aString = symbol + dataType;

12. Parse the arg[ ] into options (user,url,etc) and non-options args.
TestClient
public class TestClient {
public static void main(String args[])
try
Options opts = new Options( args );
args = opts.getRemainingArgs();
Parse the arg[ ] into options (user,url,etc) and non-options args.
get non-options args.

13. TestClient.java (2) Service service = new Service();
The start point of access SOAP web services
Default URL "
Or You can use the SOAP endpoint as in WSDL
"
Call invokes SOAP web services
Service service = new Service();
Call call = (Call) service.createCall();
call.setTargetEndpointAddress( new java.net.URL(opts.getURL()) );
if( args[0].equals("1") )
call.setOperationName( new QName("urn:HelloWorld", "sayHello") );
else
call.setOperationName( new QName("urn:HelloWorld", "addString") );
Service Name
Service Method

14. TestClient.java
Add the parameters for the remote method
Parameter name. Arbitrary. Appear in request SOAP message
XML data type for the para
IN/OUT/INOUT
call.addParameter( “p1", XMLType.XSD_STRING, ParameterMode.IN );
call.addParameter( “p2", XMLType.XSD_STRING, ParameterMode.IN );
call.setReturnType( XMLType.XSD_STRING );
call.setUsername( opts.getUser() );
call.setPassword( opts.getPassword() );
Define the return value
Security options

15. Request SOAP message <?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv=" xmlns:xsd=" xmlns:xsi="
<soapenv:Body>
<ns1:sayHello soapenv:encodingStyle=" xmlns:ns1="urn:HelloWorld">
<p1 xsi:type="xsd:string">Yuhong</p1>
<p2 xsi:type="xsd:string">Yan</p2>
</ns1:sayHello>
</soapenv:Body>
</soapenv:Envelope>
Remote method name
Name of the web service
Parameter name.
Parameter type. need to match WSDL.
Value of the parameter

16. TestClient.java
Invoke the web service
Return value
Passing parameters
String res = (String) call.invoke( new Object[] { args[1], args[2] } );
System.out.println( "Return is: " + res ); }
catch( Exception e ) {
e.printStackTrace();
}//end of class

17. Response SOAP message
<soapenv:Envelope xmlns:soapenv=" xmlns:xsd=" xmlns:xsi="
<soapenv:Body>
<ns1:sayHelloResponse soapenv:encodingStyle=" xmlns:ns1="urn:HelloWorld">
<ns1:sayHelloReturn xsi:type="soapenc:string" xmlns:soapenc=" Welcome to SOAP Web Service World!</ns1:sayHelloReturn>
</ns1:sayHelloResponse>
</soapenv:Body>
</soapenv:Envelope>

18. Inside SOAP P53, figure 3-2 SOAP message Envelope (required)
Header (optional)
Body (required)
Fault (optional)
P53, figure 3-2

19. Envelope The root element of SOAP message
Uses XML namespaces to differentiate versions
Two versions 1.1, 1.2
No third string
<soapenv:Envelope xmlns:soapenv="

20. Header (optional)
For authentication, transaction management, and payment authorization
Two defined attributes
Actor attribute: the chained node
MustUnderstand attribute: force the recipient to process the element, if not understandable, return a fault

21. Header (optional) (2) <SOAP-ENV:Header>
<ns1:PaymentAccount xmlns:ns1=“urn:ecerami” SOAP-ENV:mustUnderstand=“true”>
orsenigo473
</ns1:PaymentAccount>
</SOAP-ENV:Header>
P54. the soapheader

22. Body Where the transferred data is Data encoding via XML Schemas
<soapenv:Body>
<ns1:sayHello soapenv:encodingStyle=" xmlns:ns1="urn:HelloWorld">
<p1 xsi:type="xsd:string">Yuhong</p1>
<p2 xsi:type="xsd:string">Yan</p2>
</ns1:sayHello>
</soapenv:Body>

23. Fault (optional) faultCode SOAP-ENV:VersionMismatch
SOAP-ENV:MustUnderstand
SOAP-ENV:Client (non existing methods)
SOAP-ENV:Server (not able to access DB)
faultString
faultActor
detail

24. Fault (optional)-2 P55. xml part (for faults)
<?xml version=‘1.0’ encoding=‘UTF-8’?>
<SOAP-ENV:Envelope
xmlns:SOAP-ENV=“
xmlns:xsi=“
xmlns:xsd=“
<SOAP-ENV:Body>
<SOAP-ENV:Fault>
<faultcode xsi:type=“xsd:string”>SOAP-ENV:Client</faultcode>
<faultstring xsi:type=“xsd:string”>
Failed to locate method (ValidateCreditCard) in class
(examplesCreditCard) at /usr/local/ActivePerl-5.6/lib/
site_perl/5.6.0/SOAP/Lite.pm line 1555.
</faultstring>
</SOAP-ENV:Fault>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>
P55. xml part (for faults)

25. SOAP message inside HTTP message
SOAP is inside a HTTP message
How client-server talks in HTTP
The client identifies the server via a URI
connects to it using the underlying TCP/IP network
issues a HTTP request message (POST)
receives a HTTP response message (GET)

26. SOAP request message is within HTTP POST
Here is the HTTP header you see from the log
POST /axis/services/urn:HelloWorld HTTP/1.0
Content-Type: text/xml; charset=utf-8
Accept: application/soap+xml, application/dime, multipart/related, text/*
User-Agent: Axis/1.2alpha
Host: localhost:8080
Cache-Control: no-cache
Pragma: no-cache
SOAPAction: ""
Content-Length: 474
Authorization: Basic dXNlcjE6cGFzczE=

27. SOAP request message is within HTTP POST
Here is the HTTP body – That is the SOAP message
<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv=" xmlns:xsd=" xmlns:xsi="
<soapenv:Body>
<ns1:sayHello soapenv:encodingStyle=" xmlns:ns1="urn:HelloWorld">
<p1 xsi:type="xsd:string">Yuhong</p1>
<p2 xsi:type="xsd:string">Yan</p2>
</ns1:sayHello>
</soapenv:Body>
</soapenv:Envelope>

28. SOAP response message is within HTTP GET
This should be in HTTP header
GET /axis/services/urn:HelloWorld HTTP/1.0
Content-Type: text/xml; charset=utf-8
Accept: application/soap+xml, application/dime, multipart/related, text/*
User-Agent: Axis/1.2alpha
Host: localhost:8080 ……

29. SOAP response message is within HTTP GET
<soapenv:Envelope xmlns:soapenv=" xmlns:xsd=" xmlns:xsi="
<soapenv:Body>
<ns1:sayHelloResponse soapenv:encodingStyle=" xmlns:ns1="urn:HelloWorld">
<ns1:sayHelloReturn xsi:type="soapenc:string" xmlns:soapenc=" Welcome to SOAP Web Service World!</ns1:sayHelloReturn>
</ns1:sayHelloResponse>
</soapenv:Body>
</soapenv:Envelope>

30. Axis Client Client XML Schema Java Objects and data types XML
follows
Java Objects
and data types
XML
data types
SOAP
Server

31. Axis client Map java data types to XSD data type
Serialize java objects into XML
Send SOAP request to server (not necessarily Axis server)
Interpret SOAP response

32. XML <-> Java Data Mapping in Axis
Primitives
Beans
User Defined Types (classes)
Code Demo
References:
AXIS User Guide
AXIS sample code

33. Primitives: the mapping table
xsd:base64Binary byte[]
xsd:boolean boolean
xsd:byte byte
xsd:dateTime java.util.Calendar
xsd:decimal java.math.BigDecimal
xsd:double double
xsd:float float
xsd:hexBinary byte[]
xsd:int int
xsd:integer java.math.BigInteger
xsd:long long
xsd:QName javax.xml.namespace.QName
xsd:short short
xsd:string java.lang.String