iBeans = Dead-simple integration for web app development

iBeans = dead-simple integration + web app development Ken Yagen Silicon Valley Code Camp, October, 2009

Agenda

Introduction to Mule iBeans
Demo
How it works
Using iBeans
The Future of iBeans

What is an iBean?

A way to access external services, Facebook, AWS, eBay
A well-defined interface to a hosted service

‘ service’ can be public or internal to your company

A Java interface with annotated method
A really easy way to create a reusable component

Introduction to Mule iBeans

Dramatically simplified integration for web applications
Simple API using annotations
Works with JSP, JSF, Struts, Spring, JavaScript
Task-based integration, e.g.:

Send/receive email
Subscribe to JMS queue
Poll RSS or Twitter feed
Publish REST service

Open source
Based on Mule

Do we need another framework?

Plenty of ESB/integration frameworks out there –

Mule, Open ESB, Camel, Spring Integration

All feel SOA-influenced
Not much for the WebApp developers who just wants grab data quickly
Focus on:

Dead simple API
Reuse
Task-based integration

How it Works

Container-based approach

iBeans bundled with Tomcat, not WebApp
Auto discovery

Web Apps select services by adding servlet definitions
Full support for AJAX messaging and RPC
iBeans console used for updating and removing features
IBean and Application annotations
Modules for: Email, Scheduling, Atom, Jms, Rest, Ajax, Xml, Guice, Spring
Built with the cloud in mind

The @Call and @UriParam Annotations public interface TwitterIBean { @Call (uri = " http://www.twitter.com/statuses/show/{id}.json ") String statusesShow( @UriParam (" id ") String id) throws CallException; } All contents Copyright © 2009, MuleSoft Inc.

The @State Annotation public interface TwitterIBean { @State void init( @UriParam (“ format ”) String format); @Call (uri = “ http://www.twitter.com/statuses/show/{id}.{format} ”) String statusesShow( @UriParam (" id ") String id) throws CallException; } All contents Copyright © 2009, MuleSoft Inc.

Static Defaults public interface TwitterIBean { @UriParam (“ format ”) static String DEFAULT_FORMAT = “ json ”; @State void init( @UriParam (“ format ”) String format); @Call (uri = " http://www.twitter.com/statuses/show/{id}.{format} ") String statusesShow( @UriParam (" id ") String id) throws CallException; } All contents Copyright © 2009, MuleSoft Inc.

The @ReturnType Annotation and Generic Types public interface TwitterIBean { @UriParam (“ format ”) static String DEFAULT_FORMAT = “ json ”; @State void init( @UriParam (“ format ”) String format, @ReturnType Class retType); @Call (uri = " http://www.twitter.com/statuses/show/{id}.{format} ") <T>T statusesShow( @UriParam (" id ") String id) throws CallException; } All contents Copyright © 2009, MuleSoft Inc.

Always provide sensible defaults public interface TwitterIBean { @UriParam (“ format ”) static String DEFAULT_FORMAT = “ json ” ; @ReturnType static Class DEFAULT_RETURN_TYPE = String. class ; @State void init( @UriParam (“ format ”) String format, @ReturnType Class retType); @Call (uri = " http://www.twitter.com/statuses/show/{id}.{format} ") <T>T statusesShow( @UriParam (" id ") String id) throws CallException; } All contents Copyright © 2009, MuleSoft Inc.

Testing the iBean public class TwitterIBeanTest extends AbstractIBeansTestCase { @IntegrationBean private TwitterIBean twitter; public void testTwitter() throws Exception { twitter.init(“ xml ”, Document. class ); Document doc = twitter.statusesShow(“ 1234567890 ”); } } All contents Copyright © 2009, MuleSoft Inc.

Other Annotations Annotation Description Type @HeaderParam Configures a header on the outgoing message Param, Field @PayloadParam Used for Http, configures a POST parameter Param @Payload Attaches data to the body of the message Param @State Will store values on the instance of the bean for later reference Method @PropertyParam Adds a property to the message that can be used later i.e. user/pass for authentication Param, Field All contents Copyright © 2009, MuleSoft Inc.

Transforming Response Data public class TwitterTransformers { @Transformer protected Status twitterXmlToStatus(Document doc) { String status = selectValue(" /status/text ", doc); String user = selectValue(" /user/name ", doc); return new Status(status, user); } } All contents Copyright © 2009, MuleSoft Inc.

public class TwitterIBeanTest extends AbstractIBeansTestCase { @IntegrationBean private TwitterIBean twitter; public void testTwitter() throws Exception { registerBeans( new TwitterTransformers()); twitter.init(“ xml ”, Status. class ); Status status = twitter.statusesShow(“ 1234567890 ”); } } Testing iBeans All contents Copyright © 2009, MuleSoft Inc.

Application Annotations Annotation Description Type @Schedule Cron scheduling for calling a method, can be used to poll channels Method @Receive Receive Data on a channel URI Method @Send Send the return of the method on a channel URI Method @ReceiveAndReply Receive Data on a channel URI and send the return back to the caller Method All contents Copyright © 2009, MuleSoft Inc.

@Schedule, @Send Example public class TwitterSchedule { @IntegrationBean private TwitterIBean twitter; @Schedule (interval = 5000) @Send (uri = " ajax:///ibeans/ajax/twitter ") public Document getTimeline() throws Exception { twitter.init(“ xml ”, Document. class ) return twitter.getPublicTimeline(); } } All contents Copyright © 2009, MuleSoft Inc.