Realtime Apps with RethinkDB and Socket.io

Talk at Melbourne NodeJS Meetup. Wednesday 18th November, 2015.

Transcript

1. RethinkDB and Socket.io MAKING REALTIME WEB APPS WITH @itscatkins 1
2. Who’s this guy anyway? echo $(whoami) 2
3. WHO’S THIS GUY ANYWAY? BY DAY ▸ Senior Software Engineer at Zendesk ▸ Writes of lots of Ruby and Javascript ▸ Lots of contemplative beard stroking + 3 +
4. WHO’S THIS GUY ANYWAY? BY NIGHT ▸ Kendama Enthusiast ▸ Dreamer of Stilton ▸ Reddit induced insomniac ▸ Lover of noisey guitars 4
5. Realtime apps 5
6. REALTIME APPS EXAMPLES OF REALTIME APPS ▸ Collaboration tools ▸ Google Docs ▸ Google Wave ▸ Trello ▸ Communication Tools ▸ Slack ▸ Facebook Chat ▸ Twitter ▸ Games 6
7. REALTIME APPS TWO MAIN ISSUES ▸ Persistence ▸ How do I know when data has changed? ▸ Transport ▸ How do I send updates to to my users? 7
8. REALTIME APPS SOLUTIONS IN THE SPACE ▸ End to end – persistence + transport ▸ Meteor ▸ Firebase ▸ Hosted Messaging platforms ▸ Pusher ▸ Pubnub 8 ▸ Server push libraries ▸ Socket.io (NodeJS) ▸ SockJS ▸ SignalR (.NET) ▸ Faye (Ruby + Node) ▸ Ratchet (PHP) ▸ Traditional push solutions ▸ Ajax Polling ▸ Comet / Long polling ▸ HTML5 Server Sent Events (SSE) / EventSource
9. REALTIME APPS PERSISTENCE ▸ ActiveRecord callbacks (Rails) ▸ As CRUD actions occur in your app publish updates ▸ Very manual + error prone ▸ Tightly couples your models with other app concerns ▸ “[ActiveRecord] callbacks are the devil” – Sam Mullen 9
10. REALTIME APPS PERSISTENCE ▸ MongoDB ▸ Polling ▸ Oplog tailing ▸ Mainly for replication on sharded clusters ▸ Also used by Meteor ▸ Have to decide in the application layer what to send to who 10
12. SOCKET.IO FEATURES ▸ Client + Server Libraries ▸ Easy to install via npm ▸ Abstracts away transport via engine.io ▸ Falls back to polling on older browsers without WebSocket supply ▸ Namespaces / Rooms ▸ Broadcasting ▸ Distributed via socket.io-redis ▸ ~2 million downloads a month 12
13. 13 RethinkDB
14. RETHINKDB FEATURES ▸ JSON database ▸ Changefeeds ▸ Clustered ▸ ReQL ▸ Automatically parallelised queries ▸ Slick Administration Console http://localhost:8080 ▸ Official drivers for Python, Ruby + NodeJS ▸ Distributed Joins ▸ Map/Reduce ▸ Geospatial indicies 14
15. RETHINKDB HISTORY ▸ 2009 ▸ Started as MySQL storage engine designed to take advantage of SSDs ▸ YCombinator backed ▸ Append-only design, similar to ideas to Datomic ▸ November 2012 (1.2) ▸ First open source release, transformed into a JSON Database ▸ June 2014 (1.13) ▸ Changefeeds introduced ▸ April 2015 (2.0) ▸ Declared Production Ready ▸ August 2015 (2.1) ▸ High Availablity ▸ Automatic Failover 15
16. RETHINKDB DOWNSIDES ▸ Not sure yet ▸ No unique constraints on secondary indicies ▸ Some limitations on change feeds ▸ Tricky to secure – need SSH tunnels to db servers 16
17. ClickSquad GOTY EDITION 17
18. CLICKSQUAD BASIC GAME IDEA ▸ Teams compete in real time to click on a big blue button the most times ▸ Live leaderboard ▸ Yep. ▸ I’ll see y’all next year for my keynote at PAX 18
19. CLICKSQUAD TOOLS USED ▸ RethinkDB + Socket.io (unsurprisingly) ▸ Express ▸ Node v4.2.2 ▸ Webpack ▸ React ▸ Rethinkdbdash (alternate driver) 19
20. DEMO TIME 20 https://github.com/catkins/realtime-rethinkdb
21. QUESTIONS? 21
22. https://www.rethinkdb.com/faq/ https://www.quora.com/What-happened-to-RethinkDBs-initial-idea-approach- to-build-a-MySQL-optimized-for-SSDs-by-ripping-out-parts-meant-for-spindles http://www.infoworld.com/article/2607757/javascript/socket-io-javascript- framework-ready-for-real-time-apps.html http://samuelmullen.com/2012/01/guidelines-for-using-activerecord-callbacks/ https://www.rethinkdb.com/docs/sql-to-reql/javascript/ https://github.com/neumino/rethinkdbdash http://faye.jcoglan.com/ https://thinky.io/ http://siliconangle.com/blog/2015/04/14/rethinkdb-releases-first-production- version-of-its-real-time-database/ https://www.flickr.com/photos/davedugdale/5102910864 22