Wave Presentation

Google Wave

Monday, August 31, 2009

Google Wave for Developers
A Quick Overview

Google Wave Hackfest STL
William J. Edney
bedney@technicalpursuit.com

© 2007 William J. Edney
Last updated 20090824
You are free to use this work, with certain restrictions.
For full licensing information, please see the last slide/page.


What is Wave?

 Email re-imagined
 A uniﬁcation of email, IM, blogs
and wikis
 A new collaborative platform


But wait… there’s more…


A lot more for developers…
A real platform


A real platform
 Client


A real platform
 Client
 Server


A real platform
 Client
 Server
 Protocols (several, in fact)


Terminology


A Wave
 What the user sees in
the ‘email-like’ Web client
 A threaded discussion
 A logical grouping of wavelets


A Wavelet
 A container for 1..n blips
 Can have 1..n participants
 Entity that is hosted
 Manages access control


A Blip
 A single message
 Uses a Document to hold content
 Blips can be nested in other blips
 Uses Annotations to hold metadata


A Document
 Holds the content of a blip


An Annotation
 Holds metadata, like formatting
 Unlike HTML, formatting
information is not embedded in a
Wave Document


A Participant
 An entity that can create or edit
waves
 Can be a human
 Can be a robot (agent)


Architecture


Multi-client / single-server



GWT protocol



GWT protocol

Google protobuf



GWT protocol

Google protobuf Google protobuf



GWT protocol JSON-RPC

Google protobuf Google protobuf


Multi-client / multi-server


Multi-client / multi-server

Wave
Federation
Protocol (XMPP-
based)


Operational
Transformation


Wave is a multi-user, real-time
environment
How do we keep things in sync?


Changes to a document can be
modeled as operations
 Operations can be transformed into
other operations
 Operations can be composed
(condensed) into other operations


Operations Example
Skip 8

ElementStart
tagName: “li”

Insert
“hello”

ElementEnd

Operations are how changes are
modeled
 Operations can be transformed into
other operations
 Operations can be composed
(condensed) into other operations


Concurrency (naive)


Concurrency (correct)


Editors do not produce HTML
 Editors extract operations against
documents and store ‘metadata’ like
formatting in annotations
 Editors perform operations against
documents and, using formatting
metadata in annotations, produce the
visible result


Embed API
 Embed the Wave ‘editor’ GUI into a
web page

loadWave(waveId:String,
opt_loadCallback:Function)
addParticipant()
addReply()


Embed API tips
 For now, you must be logged in to
Wave in order to view a Wave on a
web page
 The Wave ID can only be
determined from the full client -
see the “Debug” menu
 The Wave being viewed must have
the ‘public@a.gwave.com’ user added


Gadget API
 Write Wave gadgets to use inside of
a Wave
 Similar to writing a Google Gadget

setStateCallback(callback:Function,
opt_context:Object)
setParticipantCallback(callback:Function,
opt_context:Object)
wave.getState()
submitDelta(delta:Object)


Gadget API tips/caveats
 If you want to know when your
gadget is loaded, register an ‘onload’
handler
 The full OpenSocial API isn’t
supported, but its coming
 The security model is still being
worked out - submitDelta() has no
restrictions.


Robot (Agent) API
Write your own ‘automated
participant’ for the Wave system
 Two supported languages: Java and
Python
 Runs on Google App Engine
 Has full access to a wave - its
wavelets, blips, etc.


Robot (Agent) API tips/caveats
 Only runs on Google App Engine for
now
 Think ‘events’ - wave events
received from the wave:
Wavelet Created/Removed
Participants Changed
Blip Deleted/Submitted
Document Changed


Robot (Agent) API tips/caveats
 If you’re writing in Java, you need to
manually create your capabilities.xml
ﬁle
 Don’t forget to include the Wave
client libraries as part of your project!


Conclusion


Thank you!

Email: bedney@technicalpursuit.com


Licensing of this work
This work is licensed under the Creative Commons Attribution-ShareAlike
License.

To view a copy of this license, visit
http://creativecommons.org/licenses/by-sa/1.0
or send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford,
California 94305, USA.

In addition to the rights and restrictions common to all Creative Commons
licenses, the Attribution-ShareAlike License features the following key
conditions:

Attribution. The licensor permits others to copy, distribute, display, and
perform the work. In return, licensees must give the original author credit.

Share Alike. The licensor permits others to distribute derivative works under a
license identical to the one that governs the licensor’s work.

Questions? Email bedney@technicalpursuit.com


Wave Presentation

Recomendados

Recomendados

Mais conteúdo relacionado

Destaque

Destaque (8)

Semelhante a Wave Presentation

Semelhante a Wave Presentation (8)

Último

Último (20)

Wave Presentation