Hello, World! A first look at the library Node.js® for Cloudant

Hello, World! A first look at the library
®
Node.js for Cloudant
Mike Broberg
Director of Marketing Communications, Cloudant, an IBM Company
Jason Smith
Developer Advocate, Cloudant, an IBM Company
Agenda
•  About Node.js and Cloudant
•  Why they’re best friends
•  Resources
•  Intro to the library Node.js for Cloudant
•  Questions
2
Node.js and Cloudant
•  Node.js
•  Implements everything that’s not already built into JavaScript for
writing server-side apps
•  Great at building fast, interactive Web apps
•  Cloudant
•  NoSQL JSON document data store, accessed via an HTTP API and
delivered as a fully managed database service (DBaaS)
•  Scales big, both in terms of data and concurrent users
3
Node.js: Server-Side and Small
•  “Asynchronous I/O library for file, socket, and HTTP
communication”
•  Thanks, Wikipedia
•  People use Node.js to deal with server processes, and import only
the modules they need from Node Package Manager (npm)
•  One app generally depends on dozens of Node.js modules
4
Node.js: Asynchronous, Rethought
•  Moar I/O!
•  Most apps are I/O-bound
•  In Node.js, I/O is non-blocking
•  Instead of multiple processes/threads
to perform work, Node.js uses an
event loop
•  Node.js is single-threaded,
but event-based
•  Can handle many I/O connections in a
single thread
•  I/O is event-driven & asynchronous
•  Everything runs in parallel, except your
code
•  More from blog.mixu.net and
Tom Hughes-Croucher (thanks)
5
Node.js: Stream It Like a Boss
User
client
Node.js
server
DB
•  Minimize client response time
•  Good for simple Web apps that stream data & asynchronicity is OK
•  News feeds or collaboration apps
•  Not cars or missile silos
6
Cloudant: JavaScript Object Notation
•  Cloudant is based on Apache CouchDB™ and represents
records as JSON documents
{!
"docs": [!
{!
"_id": "df8cecd9809662d08eb853989a5ca2f2",!
"_rev": "1-8522c9a1d9570566d96b7f7171623270",!
"Movie_runtime": 162,!
"Movie_rating": "PG-13",!
"Person_name": "Zoe Saldana",!
"Actor_actor_id": "0757855",!
"Movie_genre": "AVYS",!
"Movie_name": "Avatar",!
"Actor_movie_id": "0499549",!
"Movie_earnings_rank": "1",!
"Person_pob": "New Jersey, USA",!
"Person_id": "0757855",!
"Movie_id": "0499549",!
"Movie_year": 2009,!
"Person_dob": "1978-06-19"!
}!
]!
}!
7
JavaScript All the Things
•  JavaScript on the client, Node.js on the server, and JSON in the
database
Single-Language Stack
Cloudant or CouchDB
Angular.js
Node.js
Express
https://twitter.com/filmaj/statuses/415615280069353472
8
Messy Data
•  Interactive Web apps create messy data
•  The flexible, self-describing schema of JSON documents handles it
well
•  Flexible schema allows for fast agile development to add new features and
data to applications without the need for downtime or locking, like an RDBMS
9
Cloudant: (Pop and) No Locking
•  Cloudant does not enforce locking of records
•  Append-only data store
•  Don’t update documents in place; instead post new versions of the same doc,
incrementing reserved "_rev": field
•  Cloudant designed to be highly available, durable DB
•  Stores many copies of data across different physical infrastructure
•  Makes all copies available for reads & writes
•  Quorum protocol resolves changes behind the scenes
•  Eventually consistent
10
Besties
•  Asynchronous code + DB that doesn’t lock records = best friends
•  Support lots of concurrent I/O connections, process lots of data
streams, make lots of application users very happy
11
Recap
•  Node.js popular for interactive Web apps, which is a great fit for
a document store
•  JSON
•  Lots of templates and code modules available
•  npm
•  Single-language stack in JavaScript
•  CANE
•  Asynchronous code with a database that doesn't lock
•  Non-blocking I/O operations in Node.js
•  Non-locking database in Cloudant/CouchDB
12
Resources – Useful Tools
•  Cloudant blog on getting started with Node.js:
https://cloudant.com/blog/using-cloudant-with-node-js/
•  Third-party libraries:
•  nano - https://github.com/dscape/nano
•  sag - https://github.com/sbisbee/sag-js
•  cradle - https://github.com/flatiron/cradle
•  Template for Express framework:
https://github.com/cloudant-labs/express-cloudant
•  Tool to upload spreadsheet/csv into Cloudant:
https://github.com/garbados/Cloudant-Uploader
•  Getting started with Node.js on Bluemix:
http://thoughtsoncloud.com/2014/07/getting-started-ibm-bluemix-node-js/
13
Resources – Development Examples
•  Node.js CRUD example with Cloudant on Haengematte:
https://github.com/cloudant/haengematte/tree/master/nodejs
•  Twilio blog on building a Node.js app using Cloudant:
https://www.twilio.com/blog/2012/09/building-a-real-time-smsvoting-app-part-1-node-js-couchdb.html
•  Bluemix blog on building a simple word game:
http://www.ibm.com/developerworks/cloud/library/clguesstheword-app/index.html?ca=drs•  Article on integrating Rasberry Pi/Node.js/Bluemix:
http://www.ibm.com/developerworks/library/ba-remoteservpi-app/
index.html
14
Introducing Node.js for Cloudant
Cloudant’s first officially supported language-specific library
•  GitHub: https://github.com/cloudant/nodejs-cloudant
•  npm: https://www.npmjs.org/package/cloudant
•  A live code example with Jason Smith (@_jhs)
•  voxel-deathmatch: https://github.com/jhs/voxel-deathmatch
15
Thank You
mbroberg@us.ibm.com
@mikebroberg
@cloudant
jason@cloudant.com
@_jhs