c11: enabling your openedge ® application with web 2.0 ken wilner vp of technology

C11: Enabling Your OpenEdge® Application With Web 2.0

Ken WilnerVP of Technology

© 2008 Progress Software Corporation2

Content Producer

Content Consumers

Web 1.0 - Very Little Content Sharing

Web-based

Services

Users

Internet


Content Prosumers

Content Prosumers

Web 2.0 - Content Flows in All Directions

Web-based Services

Users

Internet


Web 2.0 Core Principles

User generated content Harnessing the power of the crowd Data on an epic scale Architecture of participation Network effects Openness – easy to access

What Is Web 2.0?, Design Patterns and Business Models for the Next Generation of Software, Tim O'Reilly, http://www.oreilly.com/pub/a/oreilly/tim/news/2005/09/30/what-is-web-20.html

What is Web 2.0? Ideas, technologies, and implications for education, Paul Anderson, http://www.jisc.ac.uk/media/documents/techwatch/tsw0701b.pdf

Collaboration, Contribution, and Community


Mashups

Combining data from a web-based service with your application or another web-based service

Types:• Client-side

– Presentation focused– Browser-based using Javascript, e.g. Google maps.

• Server-side– Data focused– Using your preferred programming language or

specialized tools to access service via standard protocol (api)

Applications Leveraging the Power of Web 2.0


Web 2.0 Mashups- Impact on an OpenEdge Application

Mashup Web 2.0 services with your application• Learn the api

• Use a standard protocol

Make your application mashable• Follow the “openness principle”

• Easy to access in lots of ways using standard protocols


Agenda

A Walk Through Flickr’s Web 2.0 Interface REST RSS OpenEdge and Web 2.0


Demo - Walk Through Flickr’s Web 2.0 Interface


Flickr - Open and Easy to Access

Traverse the website Access content directly

• Simple to understand URL Access programmatically

• Well-documented API

• Access via REST Be notified of changes

• Use RSS


Agenda



REST

Representational State Transfer Design pattern based on existing Web

capabilities – HTTP Resources, methods, representations Lots of nouns (resources) with a few verbs

(methods) – compare with Web Services (RPC)


Resources

The thing you are acting on, e.g. an employee, a collection of photos, etc.

Unique URL for each entity (resource)

Resources can be nested, e.g. employee last name

Format:http://<host>/<path>?<query>

• Host - location of resource• Path - name of resource• Query - filters the resource, indicates

response format, etc.


Resources - Examples

http://www.domain.com/employees • all employees

http://www.domain.com/employees/17624• employee 17624

http://www.domain.com/employees/17624/lastname• last name attribute of employee 17624

http://www.domain.com/employees/17624?format=xml• Return the result in xml format

http://www.domain.com/employees?location=France• Only the employees in France


REST – CRUD Methods

HTTP Method Meaning

POST Create (Update)

GET Read

PUT Update (Create)

DELETE Delete

Examples:

GET http://www.domain.com/employees• Get all employees

DELETE http://www.domain.com/employees/17624• Delete employee 17624

PUT http://www.domain.com/employees/17624/state• Update the state attribute of employee 17624


Representation

Format of the resource – any well-known content type, e.g.• XML - most popular

• JSON - becoming popular

• JPEG

• HTML

• Text Contains links to other resources where

appropriate


Representation - Example

GET http://www.domain.com/employees?limit=3

XML:

<Employees>

<Employee id=“17624” href=“http://www.domain.com/employees/17624” />



</Employees>

JSON:

{“Employees”:[

{“id”: “17624”,”ref”: “http://www.domain.com/employees/17624” },

{“id”: “62371”,”ref”: “http://www.domain.com/employees/62371” },

{“id”: “63412”,”ref”: “http://www.domain.com/employees/63412” }

]}


Flickr - Examples

GET http://www.flickr.com/photos/kenwilner• Ken Wilner’s photos in HTML

GET http://www.flickr.com/photos/kenwilner/2521135043/ • Ken Wilner’s photo number 2521135043 in HTML

GET http://api.flickr.com/services/rest/?method=flickr.photos.search&

api_key=d7c94440fdce1b53a39b071f471b74a0&user_id=65153788%40N00

• Ken Wilner’s photos in XML Not very RESTfulWhy not?

GET http://www.flickr.com/photos/kenwilner&api_key=d7c94440fdce1b53a39b071f471b74a0&format=XML


Agenda



RSS – Really Simple Syndication

Used to publish frequently updated web content Typically, used with news items, weblogs, web

site updates, company announcements, etc. Can reference any digital content, i.e. anything

that has a URL – use REST Easy access to all updated information from

one place


RSS Concepts

Web Server Application

RSS File

Syndicate

www.mysite.com

RSSReader

RSSReader

GET http://www.mysite.com

Response (RSS file)

RSSCache

Subscribe www.mysite.co

m Subscriptions: www.mysite.com

www.cnn.com

Aggregate

Syndication – publishing something – dynamically or statically

Subscription – saying what you are interested in

Aggregation – fetching what you are interested in

12

3

4

Read


Syndication - Readers

Browser-based • Firefox

– Live Bookmarks– Wizz RSS add-on

• Internet Explorer – V7

Desktop• infoRSS (http://inforss.mozdev.org)• NewzCrawler (http://www.newzcrawler.com)

E-mail client• Outlook 2007

Web-based• Bloglines (http://www.bloglines.com)• Google (http://www.google.com/reader)

Multiple formats• Newsgator (http://www.newsgator.com)

Summary information on multiple readers• RSS Compendium (http://www.allrss.com)


RSS Formats


RSS 2.0

<rss version="2.0“ …>

<channel>

<title>Uploads from kcdubya, tagged tahoe</title>

<link>http://www.flickr.com/photos/kenwilner/tags/tahoe/</link>

<description></description>

<item>

<title>Tahoe-73</title>

<link>http://www.flickr.com/photos/kenwilner/2521135043/</link>

<description><p><a href="http://www.flickr.com/people/kenwilner/" … </description>

</item>

<item>




</item>

<item>




</item>

</channel>

</rss>


rsschannel

RSS Message Format

…

item

title

link

description

title

link

description

item

title

link

description

Channel Properties

List of items


RSS 2.0 – Building a Document

<rss version="2.0">

<channel>

[…]

</channel>

</rss>


RSS 2.0 Channel Attributes

<rss version="2.0">

<channel>


<link>http://www.flickr.com/photos/kenwilner/tags/tahoe/</link>

<description></description>

[…]

</channel>

</rss>


RSS 2.0 Items

<rss version="2.0“ …> <channel>


<link>http://www.flickr.com/photos/kenwilner/tags/tahoe/</link> <description></description> <item>

<title>Tahoe-73</title> <link>http://www.flickr.com/photos/kenwilner/2521135043/</

link> <description> <p><ahref="

http://www.flickr.com/people/kenwilner/" …</description>

</item>[…]

</channel> </rss>


RSS 2.0 – Channel Property Elements

Property Description

title* Name of the site or blog that the feed refers to

link* URL of the site that associated with the feed

description* Description of the feed

category A self-described category for the feed. Used for sorting. Can be multiple.

cloud Used by consumer to register a Web service to be called when feed is updated.

copyright Copyright of feed

image Image to display with feed

language Language of feed, e.g. en-us

pubDate Publication date for feed

skipDays Days of week when the feed is not expected to be updated

lastBuildDate The last time the content of the channel changed.

ttl Indication of how often to check for content

* Required

Selected Elements


RSS 2.0 – Item Elements

Property Description

title* Title for the item

link* URL of the item

description* Summary description of the item

comments URL of a Web page where you can enter a comment about the page

enclosure Specifies a media object, e.g. mp3 podcast, associated with the item

guid Uniquely identifies the item within the feed. Used to detect updates to items.

author E-mail address of author of item

pubDate Date and time of publication

source The title and URL of the feed

category A self-described category for the feed. Used for sorting. Can be multiple.

* Typically specified

Selected Elements – All Theoretically Optional


Other RSS Formats


Agenda



OpenEdge and Web 2.0 Examples

REST• A library system which locates a book on

Amazon.com

• An HR system that searches sites like Monster.com and Careerbuilder.com for potential candidates

RSS• A financial site that fetches relevant news feeds for

some financial news site

• A travel site that fetches the latest photos from Flickr.com

Mashup REST and RSS Services


OpenEdge and Web 2.0

Use sockets to communicate with HTTP service• Progress Knowledge Base Solution ID: 20011

and p125506

XML-based service• DOM

• SAX

Mashup REST and RSS services


OpenEdge and Web 2.0 Examples

REST• Anything you can do with Web Services

RSS• A shipping system that indicates the status of

an order• A data warehouse system that indicates when

there is some critical problem in the warehouse

Expose Your Application as a Web 2.0 Service


OpenEdge and Web 2.0

Use AppServer™ with Web Services Use WebSpeed for REST and RSS

• REST – for simplified access– Design with simple well-defined URLs– Manipulate resources using HTTP verbs– Use DOM or SAX parser to build XML document– Consider also supporting JSON– Use CGI and modify script to convert URL to

WebSpeed URL• RSS – a powerful notification mechanism

– Use DOM or SAX parser to build RSS document– Use REST principles to point back to key resources

Expose Your Application as a Web 2.0 Service


Things We’re Thinking About…

REST adapter for OpenEdge AppServer ABL HTTP and REST objects ProDataSet to JSON serialization RSS object


In Summary

Web 2.0 – the web is a platform

Extend the value of your application with Web 2.0 technologies

Open up your application in lots of ways

Consider using REST to simplify access

Leverage RSS as a very powerful notification mechanism

Leap ahead of the

competition!!


For More Information, go to…

Books• Beginning RSS and Atom Programming, Danny Ayers

and Andrew Watt, Wrox Press, 2005• How to Do Everything with Web 2.0 Mashups, Jesse

Feiler, McGraw Hill, 2008• Pro Web 2.0 Mashups, Raymond Lee, Apress, 2008

Web Sites• O'Reilly -- What Is Web 2.0

http://www.oreilly.com/pub/a/oreilly/tim/news/2005/09/30/what-is-web-20.html

• ProgrammableWebhttp://www.programmableweb.com/


Thank You

c11: enabling your openedge ® application with web 2.0 ken wilner vp of technology

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