Vidoop CouchDB Talk

Who Am I? • Chris Anderson <jchris@apache.org> • CouchDB committer • Blog: http://jchrisa.net

Couch History • Damien Katz <http://damienkatz.net/> • Worked on Lotus Notes & MySQL • Started CouchDB in 2005 • 2006: Moved to Erlang, JSON and JavaScript • Approaching 0.9 Release

2008 Erlang User of the Year

This Talk • Hello CouchDB • Hands on with CouchApp • The Future • Get Involved

Hello CouchDB • JSON Documents • HTTP / REST (You already know the API) • ACID Storage Engine • Map Reduce Views • Replication for Freedom • Portable Standalone Applications

JSON Documents {“json” : “key / value pairs”, “_id” : “some uuid”, “_rev” : “mvcc key”, “string keys” : [1,2,3,”four”,null], “schema free” : true} Your programming language supports JSON.

JSON Documents {“json” : “key / value pairs”, “_id” : “some uuid”, “_rev” : “mvcc key”, “string keys” : [1,2,3,”four”,null], “schema free” : “ﬂexible”} Adapt data as your application changes.

HTTP / CRUD You already know the API. GET read PUT create or update DELETE delete POST bulk operation

ACID Storage Engine • Append Only • Multi Version Concurrency Control • B-Tree Indexes O(log n) • Attachment Streaming Oooh, self-similar

Map Reduce Views Docs Map { “user” : “Chris”, { “key” : “Alice”, “value” : 5 } “points” : 3 } function(doc) { { “key” : “Bob”, “value” : 7 } { “user” : “Joe”, if (doc.user && doc.points) { { “key” : “Chris”, “value” : 3 } emit(doc.user, doc.points); “points” : 10 } { “key” : “Joe”, “value” : 10 } } { “user” : “Alice”, { “key” : “Mary”, “value” : 9 } } “points” : 5 } { “user” : “Mary”, Reduce “points” : 9 } { “user” : “Bob”, “points” : 7 } function(keys, values, rereduce) { Alice ... Chris: 15 return sum(values); Everyone: 34 }

Peer-Based Replication for Freedom Triggered Incremental Filtered*

Let’s Replicate Everything! • Take full advantage of CouchDB • View-source Open Source • The Future is Distributed

But that’s not RESTful! Representational State Transfer... it’s more than just verbs, it’s the hyperlinks. Webpage Webpage Webpage Webpage ∴ We need HTML.

Render JSON Docs as HTML shows/post.js /drl/_show/sofa/post/Hello-World-For-Real-This-Time

Render Views as HTML lists/index.js /drl/_list/sofa/index/recent-posts?descending=true&limit=8

Hands On with CouchApp • CouchApp is just some ﬁlesystem helpers • Embodies “best practices” • CouchApp is not opinionated, CouchDB is. • Don’t shoot the messenger.

Install CouchApp sudo easy_install couchapp or git clone git://github.com/jchris/couchapp.git

Check Your CouchDB http://127.0.0.1:5984/_utils/

Setup Credentials Leaky Abstraction! edit: /usr/local/etc/couchdb/local.ini add: [admins] username = secretpassword

Get the Example App (ajax version) couchapp clone http://jchrisa.net/sofa-ajax/_design/sofa cd sofa couchapp push http://user:pass@localhost:5984/sofa-ajax

The Guts

First Post!

Firebug to see requests

Upgrade to real HTML couchapp clone http://jchrisa.net/drl/_design/sofa cd sofa couchapp push http://user:pass@localhost:5984/sofa

How’s it Work? Macros so functions can be in multiple ﬁles.

Templating

The Future • Key-Centric Identity? • P2P Topologies don’t leave room to trust the server. • Multi-Node clusters • High performance, large databases

Resources • #couchdb and #couchapp on irc.freenode.net • http://couchdb.apache.org for mailing lists • http://planet.couchdb.org/ • http://books.couchdb.org/relax/ • Twitter search for “couchdb”

Thank You!

http://jchrisa.net	110
http://tpno.blogspot.com	42
http://www.slideshare.net	18
http://tpno.blogspot.in	2
http://static.slideshare.net	1
http://tpno.blogspot.it	1
http://tpno.blogspot.se	1
http://tpno.blogspot.de	1

Vidoop CouchDB Talk

by Chris Anderson on Mar 12, 2009

Accessibility

Categories

Tags

Upload Details

Usage Rights

8 Embeds 176

Statistics

Vidoop CouchDB Talk — Presentation Transcript