Scala勉強会第9回 in 渋谷 発表資料

1. Lift のチュートリアルを改造
して
Twitter 連携チャットを作る
Scala 勉強会第 9 回 in 渋谷
鹿島和郎（かしまかずお）

2. 自己紹介
• 鹿島和郎（かしまかずお）
• 今日は時間があまりないので省略。

3. Agenda
• Chat App demo
• Programs used
– Lift
– Dispatch
• Code reading
• Related Technologies
– OAuth
– Comet

4. Chat App demo
• Authentication (OAuth)
• Callback
• Chat (Comet)
• Known issues

5. This app uses…
• Lift
– Web framework
– View first
– http://liftweb.net/
• Databinder Dispatch
– Library for http and http services
– Written in Scala
– http://dispatch.databinder.net/About

6. Code reading
• Basics
– index.html & OAuthTest.scala
– Boot.scala
– TwitterCallback.scala
• Comet
– index.html & Chat.scala
• Model
– User.scala

7. OAuth
• Players
– Provider (Twitter)
– Consumer (app)
– User (human)
• Steps
– The owner of the app registers it on dev.twitter.com.
– The user approves the app to use his resource via
API.
– The app gets an access token.
– The app uses the access token to use the API.
• http://www.atmarkit.co.jp/fsecurity/special/106oa
uth/oauth02.html

8. Comet
• Traditional web apps (pull)
– Request & response
– Need real time?
→ A typical approach is Ajax polling.
• Comet (push)
– Server sends data when it’s ready.
– How? → Several approaches

9. Comet (cont.)
• Implementation models
– Streaming
– Long polling (★ 今回はこっち、のはず )
• Server side
– Different challenges, approaches
→ Out of scope of this presentation
• 参考
– Wikipediaのエントリ
– Comet の正しい使い方：奥さん（ Cyboze
Labs ）

10. Comet (cont.)
• Implementation models
– Streaming
– Long polling (★ 今回はこっち、のはず )
• Server side
– Different challenges, approaches
→ Out of scope of this presentation
• 参考
– Wikipediaのエントリ
– Comet の正しい使い方：奥さん（ Cyboze
Labs ）