The document provides an overview of web services and their evolution from traditional siloed applications to today's interconnected standards-based services. It begins by describing how early applications operated independently with isolated data and functionality. It then discusses the rise of distributed computing technologies that allowed some inter-application communication but still lacked open connectivity. The document focuses on how web services standards like SOAP, REST, XML, and HTTP have enabled true interoperability and reusability across organizations and platforms. It provides examples of SOAP and REST usage and highlights some key web service specifications and standards.

1. TEACHING THE WORLD
TO SING IN HARMONY
With Web Services

2. WHO AM I?
(JUSTIN PASCHAL)
Application Architect – ADI
18 yrs experience
Early Years: COBOL, Visual Basic 4
Lately: C#, PHP, JavaScript, etc.
justin.paschal@vanderbilt.edu

3. WHO ARE YOU? Intros.

4. WHY ARE YOU HERE? Applications love solos.

5. IN THE BEGINNING
THERE WERE
COMPUTERS.
Data
Screen
Screen
Report
Report
Traditional Applications
- Seemingly Miraculous (they did stuff!)
- Financial calculations, data collection
- Screens and Reports were input/output
- “Silos” of data and functionality
- No interconnectedness
- Could always import/export
- Special coding required
- Data was rarely “fresh”

6. DISTRIBUTED
COMPUTING (RPC):
A SECOND
MELODY+ Allowed for inter-application
communication
• CORBA, DCOM, EDI
• MTS (Microsoft Transaction Server)
• JAVA Enterprise Beans
• COM+
+ Registry of available components/libraries
+ Used MOM (Message-Oriented
Middleware), a system of sending and
queuing messages
- Still closed systems, costly to develop and
maintain
- Required client/server to be on same
platform/language/architecture
- Not designed to be accessed publicly
Transaction Coordinator
DB Ops File Ops Msg Ops

7. WEB SERVICES: TRUE
HARMONY
La La La Laaaa!

8. WEB SERVICES: BEGINNINGS
HTTP became a communication standard in 1994.
XML became a standard in February, 1998.
“Web” and “Services” first put together by Bill Gates at the Microsoft
Developers Conference in July, 2000.
SOAP announced as first messaging specification by Microsoft in
2000. 1 month after the announcement of .NET Framework (June,
2000).*
“The problem was getting people to think it was good, even though
it came from Microsoft” – Andrew Layman (The First Web Services
Architect)
SOAP-CL (WSDL) arrives in fall, 2000.

9. WEB SERVICES ARCHITECTURE
(SOA)
Pros
Standards-based (XML, HTTP)
Language Independent
Reusability
Stateless Connections
Encapsulation of functionality
Simpler, cheaper to maintain
Cons
Learning Curve
Verbose
Stateless Connections

10. WHY/WHEN WOULD YOU USE WEB
SERVICES?
External access to YOUR data or processes (server)
Want to consume other’s data or processes (client)
When data needs to be validated/approved
Make your web application *appear* to be faster or more responsive
Different applications need to use the same business rules
(reusability)
??

11. WEB SERVICE STANDARD:
SOAP
XML-based messaging in a
major key.

12. SIMPLE OBJECT ACCESS
PROTOCOL (SOAP)
Widely supported
HTTP as delivery mechanism, XML as messaging
Platform, Language independent
Uses “envelopes” to contain messages (request/response)
Dozens of specifications for enterprise
WS-Security
WS-Policy
WSDL for discovery
Many tools support proxy generation, language-specific
implementations

13. WEB SERVICES STANDARD:
XML/SOAP
Request
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:con="http://itsm.vanderbilt.edu/services/configuration/">
<soapenv:Header/>
<soapenv:Body>
<con:GetCIByName>
<!--Optional:-->
<con:apiKey>ASDF123</con:apiKey>
<con:ciName>PEGASUS</con:ciName>
</con:GetCIByName>
</soapenv:Body>
</soapenv:Envelope>

14. WEB SERVICES STANDARD:
XML/SOAP
Response
<soap:Envelope ..>
<soap:Body>
<GetCIByNameResponse xmlns="http://itsm.vanderbilt.edu/services/configuration/">
<GetCIByNameResult>
<Success>true</Success>
<Message>Successful Response.</Message>
<CIData>
<CIModelExtension>
<AdminID>33</AdminID>
<AdminName>ADI - SERVICE DELIVERY SOLUTIONS</AdminName>
<Name>PEGASUS</Name>
<StatusName>Installed</StatusName>
</CIModelExtension>
</CIData>
</GetCIByNameResult>
</GetCIByNameResponse>
</soap:Body>
</soap:Envelope>

15. WEB SERVICE STANDARD:
REST
It doesn’t mean PAUSE.

16. REPRESENTATIONAL STATE
TRANSFER (REST)
New(er), young(er) than SOAP
Designed to be leaner, faster, less complicated than other options
Platform, Language independent
Uses URIs and HTTP Methods to determine actions and responses
5 basic principles:
Give every “thing” an ID
Link things together*
Use standard methods
Resources with multiple representations
Communicate statelessly

17. USING STANDARD
METHODS
Using the HTTP protocol as intended
HTTP Methods:
• GET
• POST (insert)
• PUT (update)
• DELETE

18. WEB SERVICES STANDARD: REST
GET
https://wstest.mc.vanderbilt.edu/core/a
pi/secure/{KEY}/emailprocessing/outbox
HTTP/1.1
Accept-Encoding: gzip,deflate
Host: services.mc.vanderbilt.edu
Connection: Keep-Alive
User-Agent: Apache-HttpClient/4.1.1
(java 1.5)
Request
POST
/users
HTTP/1.1
Host: myserver
Content-Type:
application/xml <?xml
version="1.0"?>
<user>
<name>Robert</nam
e> </user>

19. WEB SERVICES STANDARD: REST
{
"EmailItems": [ {
"ExchangeProperties": {
"Id": null,
"ConversationId": null
},
"ID": "ef70454ba333486c929b5bcaf8a0e212",
"FromName": null,
"FromAddress": null,
"To": “someone@Vanderbilt.Edu",
"Cc": null,
"Subject": "Incident created for {CI}",
"Body": “{BODY}”,
"HasAttachments": false,
"Attachments": [],
"ModuleID": 1,
"ItemResourceID": "IM1261589",
"EmailDate": "2015-07-21T22:20:11",
"EmailType": 0,
"ParentEmailTrackingID": null,
"IsRead": false,
"ReadDate": null,
"ReadBy": null,
"MatchesRule": false,
"MatchedRuleName": null
}],
"ConfigurationData": null,
"Success": true,
"Message": null,
"RawData": null
}
Response

20. DEMOS Watch me now, hey!

21. ONLINE RESOURCES
Understanding Web Services (Basics) -
http://www.ibm.com/developerworks/webservices/tutorials/ws-
understand-web-services1/ws-understand-web-services1.html
RESTful Web Services (Introduction) -
http://www.ibm.com/developerworks/library/ws-restful/
SOAP UI (free Web Services testing tool) -
http://www.soapui.org/downloads/soapui/open-source.html
Web Service Frameworks List -
https://en.wikipedia.org/wiki/List_of_web_service_frameworks