SOAP

1
SOAP

• Ashish V. Tendulkar
• Directory Database integration group
• (www.eusersolutions.com)
• Persistent Systems Pvt. Ltd. Pune
• (www.pspl.co.in)

2
Outline

• The problem..
• Why XML?
• Why HTTP?
• XMLHTTP SOAP
• SOAP Details
• Uses of SOAP
• Example

3
The problem..
Proxy Server
Server
Client App.
Application Server
Firewall
4
Implications

• Industry not shifted completely to either one
• Vendor specific
• Lack of interoperability
• Require high-tech runtime environment

5
Why XML?

• Simple text markup language
• Platform, language and vendor agnostic
• Easily extensible
• Capable of solving interoperability problem

6
Why HTTP?

• Ubiquitous
• Supported by every web browser and server
• Effective technology for transferring text,
  graphics and other information

7
XML HTTP SOAP

• HTTP is used for transport
• XML as encoding scheme
• Endpoint HTTP based URL for the target
• Object mapping implementation specific

8
SOAP call anatomy
9
SOAP Component
Object Endpoint ID
Method/Interface ID
Extension Headers
Parameter Data
Call element
10
Uses of SOAP

• SOAP greatly simplifies data exchange in B2B
  application over extranet
• Enables web site to integrate services from other
  sites
• Remote scripting more prevalent with SOAP
• Non-browser client could seamlessly access a
  service across web

11
Example Message

• POST /string_server/Object17 HTTP/1.1
• Host 209.110.197.2
• Content-Type text/xml
• Content-Length 152
• SOAPMethodName urnstrings-comIStringreverse
• ltEnvelopegt
• ltBodygt
• ltmreverse xmlnsm'urnstrings-comISt
  ring'gt lttheStringgtHello, Worldlt/theStringgt
  lt/mreversegt
• lt/Bodygt
• lt/Envelopegt

12
Example Response

• 200 OK
• Content-Type text/xml
• Content-Length 162
• ltEnvelopegt
• ltBodygt
• ltmreverseResponse xmlnsm'urnstrings-
  comIString'gt
• ltresultgtdlroW ,olleHlt/resultgt
• lt/mreverseResponsegt
• lt/Bodygt
• lt/Envelopegt

13
Conclusion

• SOAP is platform independent, language neutral
  protocol
• SOAP does not replace COM and CORBA
• SOAP works in place of DCOM and IIOP
• SOAP does not pose huge security risks
• Supports interoperation between different vendor
  specific implementations