A presentation on Google Wave (well, at least what was known as of Aug 25th, 2009 ;-) )

1. Google Wave
Monday, August 31, 2009

2. 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.
Monday, August 31, 2009

3. What is Wave?
 Email re-imagined
 A unification of email, IM, blogs
and wikis
 A new collaborative platform
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11. But wait… there’s more…
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12. But wait… there’s more…
A lot more for developers…
A real platform
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13. But wait… there’s more…
A lot more for developers…
A real platform
 Client
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14. But wait… there’s more…
A lot more for developers…
A real platform
 Client
 Server
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15. But wait… there’s more…
A lot more for developers…
A real platform
 Client
 Server
 Protocols (several, in fact)
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17. Terminology
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18. A Wave
 What the user sees in
the ‘email-like’ Web client
 A threaded discussion
 A logical grouping of wavelets
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19. A Wavelet
 A container for 1..n blips
 Can have 1..n participants
 Entity that is hosted
 Manages access control
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24. A Blip
 A single message
 Uses a Document to hold content
 Blips can be nested in other blips
 Uses Annotations to hold metadata
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27. A Document
 Holds the content of a blip
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28. An Annotation
 Holds metadata, like formatting
 Unlike HTML, formatting
information is not embedded in a
Wave Document
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29. A Participant
 An entity that can create or edit
waves
 Can be a human
 Can be a robot (agent)
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30. Architecture
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39. Multi-client / single-server
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40. Multi-client / single-server
GWT protocol
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41. Multi-client / single-server
GWT protocol
Google protobuf
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42. Multi-client / single-server
GWT protocol
Google protobuf Google protobuf
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43. Multi-client / single-server
GWT protocol JSON-RPC
Google protobuf Google protobuf
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44. Multi-client / multi-server
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45. Multi-client / multi-server
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46. Multi-client / multi-server
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47. Multi-client / multi-server
Wave
Federation
Protocol (XMPP-
based)
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48. Operational
Transformation
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49. Wave is a multi-user, real-time
environment
How do we keep things in sync?
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50. Changes to a document can be
modeled as operations
 Operations can be transformed into
other operations
 Operations can be composed
(condensed) into other operations
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51. Operations Example
Skip 8
ElementStart
tagName: “li”
Insert
“hello”
ElementEnd
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52. Operations are how changes are
modeled
 Operations can be transformed into
other operations
 Operations can be composed
(condensed) into other operations
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53. Concurrency (naive)
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54. Concurrency (correct)
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55. 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
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56. API
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57. Embed API
 Embed the Wave ‘editor’ GUI into a
web page
loadWave(waveId:String,
opt_loadCallback:Function)
addParticipant()
addReply()
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58. 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
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59. 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)
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60. 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.
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61. 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.
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62. 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
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63. 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!
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64. Conclusion
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65. Thank you!
Email: bedney@technicalpursuit.com
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66. 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.
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Share Alike. The licensor permits others to distribute derivative works under a
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Questions? Email bedney@technicalpursuit.com
Monday, August 31, 2009