developing a google wave extension
DESCRIPTION
Learn how to build a Wave robot from the ground up using Google App Engine, Java, and Eclipse. We walk through setting up your development environment, writing the extension, and deploying, troubleshooting, and packaging it. These slides are from a talk given at Silicon Valley Code Camp 2009.TRANSCRIPT
Austin Chau and Brian KennishGoogle Developer Relations
Developing a Google Wave ExtensionSilicon Valley Code Camp 2009
Topics
Writing and Deploying
Packaging
Questions
Introduction to Wave
Setting Up Your Development Environment
Troubleshooting
Introduction to Wave
Using Wave
What would email look like if it was invented today, rather than 40 years ago?
Wave combines email and many communication technologies since — instant messaging, bulletin boards, wikis, real-time document collaboration — in one place.
It's also a protocol and platform.
Developing with Wave: The Protocol
We want lots of Waves besides Google Wave, so we're drafting the protocol specification in public and open sourcing our client and server code.
http://www.waveprotocol.org/
Developing with Wave: The Platform
Embeds bring Wave to the world.
Extensions bring the world to Wave:• Gadgets let you safely run untrusted code in a wave.• Robots are automated wave participants.
Developing with Wave: Terminology
wave — A conversation and shared document in Wave.
wavelet — The unit of access control in a wave.
blip — A message in a wavelet.
Setting Up Your Development Environment
Tools
Robots are currently required to use Google App Engine. You can sign up for an account at http://appengine.google.com/.
Java robots are also required to use the Wave Java SDK (Python robots are possible too). You can download the latest JARs from http://code.google.com/p/wave-robot-java-client/downloads/list.
Using Eclipse isn't required, but we recommend doing so because the Google Plugin makes it easy to create and deploy App Engine applications. You can install the plugin via http://code.google.com/eclipse/.
Writing and Deploying
The Robot WAR File
/war/WEB-INF/web.xml binds the robot servletsto the Wave endpoints.
/war/WEB-INF/appengine-web.xml specifiesthe App Engine identifiers.
/war/_wave/capabilities.xml subscribes the robot to Wave events.
Sample Code: Hello-Worldy
Does "hello world"-type stuff.
Appends text, echoes submittedblips, and implements form UI.
http://code.google.com/p/google-wave-resources/source/browse/trunk/samples/extensions/robots/java/hello-worldy/
Sample Code: Stocky
Replaces stock symbols withreal-time quotes.
Incorporates third-party data intoWave.
http://code.google.com/p/google-wave-resources/source/browse/trunk/samples/extensions/robots/java/stocky/
Sample Code: Embeddy
Generates code to embed awave in your webpage.
Features all three of the currentWave APIs and two-way robot-to-gadget communication.
http://code.google.com/p/google-wave-resources/source/browse/trunk/samples/extensions/robots/java/embeddy
Troubleshooting
Tips
Check your App Engine logs for errors.
Go tohttp://app-id.appspot.com/_wave/capabilities.xml tosee if your capabilities file is live.
Make sure you updated your capabilities version string after adding events.
Increase your log level in/war/WEB-INF/logging.properties, e.g., toALL.
Packaging
The Extension Installer
Extension Hooks:• NEW_WAVE_MENU• TOOLBAR
Extension Actions:• createNewWave• addParticipants
<menuHook location="TOOLBAR" iconUrl="http://hello-worldy.appspot.com/images/robot.jpg" text="Add Hello-Worldy"> <addParticipants> <participant id="[email protected]" /> </addParticipants></menuHook>
Questions
Contact Us
Brian KennishGoogle Wave and Chrome
[email protected]://twitter.com/byoogle
Austin ChauGoogle Wave and YouTube