Spacebrew @ SFPC

Spacebrew at SFPC - Brett Renfer

Spacebrew @ SFPC10/28/2014

Spacebrew at SFPC - Brett Renfer

Spacebrew Basics

Spacebrew at SFPC - Brett RenferObligatory hype video!

Spacebrew at SFPC - Brett Renfer

Spacebrew…• is a service and toolkit for choreographing interactive spaces

• makes it easy to connect interactive things to one another over networks

• was developed to support prototyping-driven design efforts

Spacebrew at SFPC - Brett Renfer

Spacebrew is supported by a group of amazing people.

Arduino Day - NYU ITP - Brett Renfer & Julio TerraRemote Presence Experiments Havas Madsci Lab

Whispering Stairs, Shu Yang Lin

Next Round Gustavo Faria, Bernardo Schorr and Stephanie Burgess

Forget Me Not Remote Flower Watering, Lucy Matchett, Joselyn McDonald, Nicole Messier

Spacebrew at SFPC - Brett Renfer

client app

client app

client app

client app

Client-Server ModelEach client can feature one or more publishers and subscribers. The server can be hosted online or run on a local network.

Spacebrew at SFPC - Brett Renfer

client app

client app

client app

client app

Client-Server ModelClients communicate with the server via WebSockets. All data is formatted as JSON

Spacebrew at SFPC - Brett Renfer

Client-Server ModelThe server routes all publishers and subscribers. Routes can be edited in real time via a switchboard-like interface

Spacebrew at SFPC - Brett Renfer

Data TypesThree standard types allow for quick and easy routing. Custom types are also supported

= true or false

= 0-1023

= “some text”

Spacebrew at SFPC - Brett Renfer

Data TypesEach publisher and subscriber announces its type, allowing for automatic routing between different apps

= true or false

= 0-1023

= “some text”

Spacebrew at SFPC - Brett Renfer

LibrariesSpacebrew aims to be implementation agnostic.We want to use the right tools at the right time!

JS

Spacebrew at SFPC - Brett Renfer

Why?• Create a glue between our favorite toolkits and languages

• Focus on real-time communication

• Wanted to build a toolkit with a low floor and a high ceiling

Spacebrew at SFPC - Brett Renfer

Using Spacebrew

Spacebrew at SFPC - Brett Renfer

Thinking About Apps• We try to silo apps whenever possible • Create specialized apps that are easy to re-use • Allows for multiple languages for each need • Quickly and easily move between machines/networks when necessary

• Allows for easy prototypes in the future!

Spacebrew at SFPC - Brett Renfer

Thinking About Prototypes• What’s the quickest path to a prototype?

• Can you use one of the existing examples?Or multiple examples? • Phone can become a “jump sensor”,string example can stand-in for Twitter or text messaging

Spacebrew at SFPC - Brett Renfer

Spacebrew LibrariesEach Spacebrew library: • Connects to a Spacebrew server (via WebSockets)

• Has an API to declare its publisher(s) and subscriber(s)

• Can send + receive messages to/from Spacebrew

Spacebrew at SFPC - Brett Renfer

Spacebrew LibrariesConnecting to Spacebrew

1. Create a Spacebrew Object

2. Tell your object where Spacebrew server is

3. Declare any publishers and subscribers

4. Connect!

Spacebrew at SFPC - Brett Renfer

Spacebrew + Processing• install the library at ~/Documents/Processing/libraries (make the folder if it doesn’t exist!)

• restart Processing if it was open

• open the spacebrew_base example to get started!

Spacebrew at SFPC - Brett Renfer

Spacebrew + Arduino• Two routes:

• the easy road: use Processing + Serial

• the road less travelled: Spacebrew Arduino libhttp://github.com/labatrockwell/spacebrew-arduino-library

• requires Arduino Ethernet shield • notoriously difficult to debug!

Spacebrew at SFPC - Brett Renfer

Spacebrew + Javascript• spacebrew.js is a stand-alone script that can run in any browser that supports WebSockets

• this includes: Chrome (OS X, Windows, Android, iOS), Safari (OS X, iOS), Firefox, Opera, IE 10

• open the spacebrew slider example in your text editor

• open http://bit.ly/sbslide on your smartphone

• also try http://bit.ly/sbaccel

Spacebrew at SFPC - Brett Renfer

Spacebrew + openFrameworks• ofxSpacebrew connects to Spacebrew via ofxLibwebsockets

• once you have both installed, you can create ofxSpacebrew projects via the OF project generator

• let’s look at example_button

Spacebrew at SFPC - Brett Renfer

Custom Types

Spacebrew at SFPC - Brett Renfer

Custom Types• Spacebrew supports arbitrary type names and data (anything that reads as valid JSON will work)

• Similar to built-in types, you can only route to matching names (e.g. we might know that “float” could probably route to “int”, but to Spacebrew they’re wholly different)

Spacebrew at SFPC - Brett Renfer

Spacebrew at SFPC - Brett Renfer

Example: Ultrabook Tree• Each input station sent a custom “bloom” object:

• Which image (id) • Number of laptops • Radius • Relative position (x,y) • Velocity • Rotation

Spacebrew at SFPC - Brett Renfer

Custom Type Demo• https://github.com/robotconscience/spacebrew-JSON-examples

• JSON in spacebrew.js, ofxSpacebrew, and spacebrewP5

• Why JSON? • It’s a simple way to send arbitrary objects • Spacebrew uses it, so all libs have some sort of JSON library included (if there isn’t one built in)

Spacebrew at SFPC - Brett Renfer

You Got Served

Spacebrew at SFPC - Brett Renfer

Running Your Own Server• Why?

• sandbox.spacebrew.cc is on the slowest AWS tier

• Running over the internet introduces some level of latency

• Running a local server OR a remote server allows a level of control: only people you choose can route/reroute, break your routes, etc

• Allows you to customize the server code if you choose!

Spacebrew at SFPC - Brett Renfer

Running Your Own Server• How?

• Setup! Only needs to be done once

• Download and install nodejs: www.nodejs.org

• Install node dependencies:

• npm install ws • npm install forever-monitor

Spacebrew at SFPC - Brett Renfer

Running Your Own Server• How?

• Run! What you’ll do every time:

• In terminal, cd to the spacebrew directory

• Run: node node_server_forever.js

Spacebrew at SFPC - Brett Renfer

Keep in touch!@robotconscience brett@robotconscience.com

@spacebrewcc spacebrew.cc

Spacebrew at SFPC - Brett Renfer

Bonus stuff

Spacebrew at SFPC - Brett Renfer

More on WebSockets• What? • Full-duplex (simultaneous input + output) TCP protocol • Fast, simple to use, (relatively) simple to implement • Allows both simple messages (strings, JSON, etc) and binary data steams

• http://tools.ietf.org/html/rfc6455

• Why? • Works in many languages across many platforms • Works over the internet and on local networks • Super easy to debug!

Spacebrew at SFPC - Brett Renfer

Persistent Admin

Spacebrew at SFPC - Brett Renfer

Persistence• Another advantage of running your own server is you can use the persistent admin

• The persistent admin is a separate service that lets you edit, save, load, and persist routes

• It allows you to specify specific app routings:coolApp -> coolPub to lameApp -> lameSub

• It also allows for powerful wild card routings: .* -> coolPub to .* -> lameSub

• This routes any app that publishes “coolPub” to any other app that subscribes to “lameSub”

Spacebrew at SFPC - Brett Renfer

Persistence• You can run the persistent admin from the spacebrew directory:node node_persistent_admin.js

• Run it in parallel with your server!

• From the command line, you can list, add, remove, load, and save routes:

• list: ls

• add: add client1Name,pub,client2Name,sub • use .* to create a wildcard

• remove: remove [index] • you can find an index after add or by listing

• save / load (just that!) • load is called on start automatically

Spacebrew at SFPC - Brett Renfer

Admin API

Spacebrew at SFPC - Brett Renfer

The Admin API• You don’t just have to use our web interface!

• Javascript, openFrameworks and Cinder (Processing soon) support the Admin API

• The Admin API subscribes to Spacebrew similar to a client, firing events each time a client connects/disconnects or changes its pub/sub map

• It allows you to view, edit, and add any and all routes in real time!

• This allows for apps like the Admin Randomizer from the Zip! Zap! Zow! exercise

Spacebrew at SFPC - Brett Renfer

The Admin API• Try it out: http://bit.ly/sbslider-admin

• Let’s look at the Admin API in Javascript