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Web 2.0 PatternsShaping the Geoweb
Introduction to the GeowebGregory L. GuntherUniversity of Colorado at Denver
Common Web 2.0 Patterns Influencing the Geoweb Service Oriented Architecture (SOA) Software as a Service (SaaS) Participation-Collaboration Asynchronous Particle Update Mashup Rich User Experience Collaborative Tagging Structured Information
Formulated By Real Examples….
Pattern Formulation
(Govenor et al. 2009)
PatternContext
Derived RequirementsProblem
Business problem (story)Context
Generalized• Specifications, static structure, dynamic behavior
Consequences References Business problem resolved Implementations• Known use
Service Oriented Architecture
No single definition (ubiquitous, depends on context)
Standardized framework or software architecture which implements interoperable software components (web services)
SOA brings a new way to look at applicationsSeparates messages from processingProvides consistent platform for interoperability
“is an architectural paradigm, a way of architecting a framework for matchingneeds and capabilities. A key feature of SOA is support for integratingservices that are owned and managed independently” (OASIS 2006)
(Govenor et al. 2009)
Principles of SOA
Simplicity (At least now) Loose Coupling
Separates messages from processing Reusable, modular Facilitates integration, eliminates
stovepipe barriers Not just technology
(King, 2006, ESRI 2007)
Classic SOA Reference Model
(King, 2006)
SOAP and WSDL
SOA Dynamic Behaviors Refined
Request/Response Via Registry
Subscribe/Push
Probe/Match
(Govenor et al. 2009)
Quick Word On SOAP
“is a protocol for exchanging XML-based messages over computer networks, normally using HTTP. SOAP forms the foundation layer of the Web services stack, providing a basic messaging framework that more abstract layers can build on”
Envelope Format: A way of putting data into an envelope
“Big Web Services”
SOA Implementation
(SOA Tag Cloud, 2009)
REST
HTTPXML/JSON/GeoRSSResource Oriented ArchitecturesMashupsAsynchronous Particle Update
(Richardson, 2007. Govenor et al. 2009)
Software as a Service (SaaS)
(Govenor et al. 2009)
EmailSpam
Filtering Software
Client
Client
Client
Rules Collect
or
http://www.esri.com/events/uc/images/workshops/cloud.html
The web IS the platform
(Morehouse et al. 2009)
Web GIS and the Cloud
Participation-Collaboration
(Govenor et al. 2009)
Asynchronous Particle Update (AJAX)
Time
Length of timeBlocked from further Input
Network LatencyProblem
(Crane et al. 2006)
Concepts related to software usability Based on usability expert Alan Cooper
Transient: used everyday but only in short burst and often as a secondary activity Delays are tolerated Examples
File System manager Amazon Search Engines
Sovereign: requires users full attention Used more intensely Desktop applications Delays become intolerable (2 second delay each
time you type a letter in a Word Processor
Sovereign and Transient Usage Patterns
(Crane et al. 2006)
Web Application LifeCycle
Just ViewsOf the User and ApplicationData Model
TraditionalInitial DataAnd ApplicationDownload
(Crane et al. 2006)
(Crane et al. 2006)
(Crane et al. 2006)
Mashup
{}
Web Server(www.gishacks.com)
Web Browser
Mashup
{}
{}{}
Node1
Node1
CSS Styling(If Applicable)
DOM
XMLData
www.google.com
JavaScript Logic
GXmlHttpXML HTTP Request
(AJAX)
MapData
Usergishacksserver
googleserver
Request Page
Return Page
API
XML Data
Map Data
Page LoadedRequest and Get XML
Request and Get Map
Rich Internet Application
Flex 3 Component Explorer: http://tinyurl.com/2o78vd
ADOBE FLEX
MS SilverlightJavaFX
Collaborative Tagging
“users add metadata in the form of keywords to shared content “
Structured Information
MICROFORMATS
POSH
GEO
Semantic XHTML
hCard
vCard
hCalendar
(Microformat. 2009)
Additional Patterns
Constant Beta The Synchronized Web Declarative Living and Tag
Garderning Semantic Web Grounding Persistent Rights Management
Conclusions Bottom-up prevails while top down does not.
REST vs SOAP Folksonomy vs Taxonomy Crowdsourced vs. traditional media
Time Magazine person of theYear 2006— You! Systems get better the more people use them The web is the system platform Persistence of Web 2.0
Architectures and platforms where people can participate beat websites
Plug-in business models Simplicity and scalability Agility Ease of use Security and privacy
(Govenor et al. 2009)
Geoweb
GIS 2.0
Web 2.0 and the Geoweb Web as platform Continuous improvement Lightweight programming models
and techn0logies Immersive (social, RIA) YOU
Law 2.0
Gov 2.0
Library 2.0
Media 2.0
References Cited
Crane, Dave, Eric Pascarello and Darren James (2006). AJAX in Action. Connecticut: Manning Publishing.
ESRI. (2007). Geospatial Service Oriented Architectures. ESRI Whitepaper. http://www.esri.com/library/whitepapers/pdfs/geospatial-soa.pdf
Governor, James, Dion Hunchcliffe and Duane Nickull (2009). Web 2.0 Architectures. California: O’Reilly Media Inc.
King, JJ. SOA What? Introduction to Service Oriented Architecture. Rocky Mountain Oracle Users Group. Denver, 2006.
References Cited
Microformat. (2009, August 13). In Wikipedia, The Free Encyclopedia. Retrieved 07:50, August 13, 2009, from http://en.wikipedia.org/w/index.php?title=Microformat&oldid=307705991
Morehouse, Scott, Gorter, Dirk and Brenda Wolfe. 2009, Taking Advantage of The Cloud, ESRI 2009 International Users Conference, San Diego, CA, San Diego Convention Center.
OASIS. (2006). Reference Model for Service Oriented Architecture 1.0. http://www.oasis-open.org/committees/download.php/19679/soa-rm-cs.pdf
Richardson, Leonard, Ruby,Sam (2007). RESTful Web Services California: O’Reilly Media Inc.
SOA Tag Cloud. Swik.com. 09 August 2009 http://swik.net/SOA?tagCloud.