- Web Worker context compared to SSJS context - Mixte Synchronous / Asynchronous APIs - Making Existing Client-side JS APIs recommendations adaptable to the server context - Defining W3C recommendation for Server-side JavaScript APIs? - Remote debugging for Remote (Server) Workers - Potential common package/module format support (CommonJS, AMD, ECMAScript 6) - DOM Events, ProgressEvent, EventSource, Server Events (EventEmitter?), & Client Events - Feedback on previous work at CommonJS and from some SSJS implementations - Feedback on our experiences in the Wakanda implementation - start the activity of the community group

1. End-to-end
W3C APIs
By Alexandre Morgaut
TPAC 2012 - Lyon, France

2. Agenda
• The Web & JavaScript
• W3C APIs
• Server-Side JavaScript
• Web Applications
• Now & Tomorrow

3. The Web & JavaScript

4. REST
• Representational State Transfer
• Client-Server
• Stateless, Cache, Uniform Interface
• Layered System
• Code on Demand: JavaScript
• defined in 2000 by Roy Thomas Fielding

5. Web Standards

6. W3C
• Created at the MIT in 1994
• Led by Tim Berners-Lee and Dr. Jeffrey Jaffe
• Joint agreement among three "Host Institutions"
• MIT, ERCIM, Keio University
• Working Groups
• HTML, MathML, RDF, SVG, CSS, Audio, Device...

7. ECMA
• European Computer Manufacturers Association
• Standards
• CD-ROM, ECMAScript, C#, Office Open XML File Formats
• JavaScript
• ECMA-262 aka ECMAScript aka ISO/IEC 16262
• TC39-TG1 managed by Mr. J. Neumann
• E4X: ECMAScript for XML
• ECMAScript Internationalization API
• Test262
http://wiki.ecmascript.org

8. W3C on Server-Side ?

9. DOM
• Java
• JavaScript
• .NET
• PHP
• python
• ..;

10. Server-Side JavaScript

11. Standards
• ECMAScript
• CommonJS
More than 60 SSJS implementations

12. Servers
• Microsoft IIS
• Persevere
• Jaxer
• node.js
• Wakanda
• RingoJS
• SilkJS

13. NoSQL Databases
• CouchDB
• MongoDB
• Riak
• WakandaDB
• ArangoDB
• OrientDB

14. Web Application “1.0”

15. HTML5 APIs
• XMLHttpRequest 2 • Web Cryptography
• Blob • ImageData
• File / FileSystem • Typed Arrays
• Web SQL • Storage Quota
• Web Storage • System Information
• Web Workers • URL
• Web Sockets • WebCL

16. WebCL
“This section proposes mechanisms for transferring pixel
data between WebCL memory objects and HTML media
elements. Server-side or Web Worker based
implementations of WebCL will not be
required to support these features.”
https://cvs.khronos.org/svn/repos/registry/trunk/public/webcl/spec/latest/index.html#4

17. Web SQL
“This document was on the W3C Recommendation track
but specification work has stopped.The specification
reached an impasse: all interested implementors
have used the same SQL backend (Sqlite),
but we need multiple independent
implementations to proceed along a standardisation
path.”
http://www.w3.org/TR/webdatabase/

18. Async “and” Sync
• XMLHttpRequest(method, url, async)
• FileReaderSync()
• requestFileSystemSync()
• openDatabaseSync()
• indexedDBSync.open()
• localStorage.getItem()

19. IndexedDB
“The synchronous database API methods provide a
blocking access pattern to IndexedDB databases. Since
they block the calling thread they are only
available from workers.”
http://www.w3.org/TR/IndexedDB/#sync-database

20. Web Workers
• Dedicated or Shared
• No Window, No Document
• WorkerGlobal, WorkerUtils
• WorkerNavigator, WorkerLocation
• postMessage(), onmessage(), onerror()
• importScripts()

21. Concept
• Server JS contexts == Workers
• multi-threaded -> Dedicated Workers
• single threaded EventLoop -> Shared
• Server JS contexts === Remote JS Workers

22. Now & Tomorrow

23. RingoJS
• W3C
• Web Worker
• CommonJS
• Modules
• System, fs, binary, IO, Unit Test
• Other: console

24. SilkJS
• W3C
• XMLHttpRequest
• CommonJS
• Modules

25. node.js
• W3C via modules
• XMLHttpRequest (node-xmlhttprequest)
• Web Sockets (node-websocket-client)
• DOM (node-o3-fastxml), IndexedDB (perstore)
• CommonJS
• Modules, Packages
• Other: console

26. Wakanda
• W3C
• XMLHttpRequest, WindowTimer,
• Web Storage, Web Worker,
• File, FileSystem, Blob, ...
• CommonJS
• Modules, System, Unit Test
• Other: console

27. Wakanda
• Web Storage
• sessionStorage, user.storage, storage
• Web Workers
• Worker, SharedWorker, SystemWorker

28. Wakanda
• Server-side JS context
• CommonJS (module.id, require, ...)
• Worker (importScripts, WindowTimer, ...)

29. Summary
• ECMAScript is already everywhere
• Modules: CommonJS already standard, AMD, ECMAScript 6
• Many W3C APIs already applicable server-side
• Same APIs means
• better learning curve
• more shared libraries / modules
• DRY -> shared Model work Offline

30. Client and Server JavaScript APIs
W3C Community Group
http://www.w3.org/community/jseverywhere/
Let’s start!