Whipped Cream
HTTP topping for Raspberry Pi
Whipped Cream is a tool which does a couple of things:
- Parses a simple plugin DSL to create web servers for Raspberry Pi I/O (input and output).
- Creates and tests plugins on your computer.
- Deploys plugins to your Rapsberry Pis.
It has a CLI (command line interface) command which parses a plugin:
name "Garage"
button "Open/Close", pin: 18
...and can start a web server:
$ whipped-cream start garage.rb
...which can be deployed to your Pi:
$ whipped-cream deploy garage.rb 192.168.1.123
...
Getting Started
Get a Pi
You'll need:
- Raspberry Pi
- Power adapter
- 4GB+ SD Card
You might also want:
- Solderless breadboard & jumper cables, for prototyping
- GPIO breakout cable (Adafruit), for easily extending the GPIO pins to your breadboard
- Mini USB wifi adapter, for placing the Pi anywhere in your house when you're done
- A case for your Raspberry Pi
Install Ruby on your computer
Whipped Cream runs on Ruby 1.9.3 and above.
Mac
We recommend ruby-install for installing Ruby versions, and chruby for switching between them. RVM will also work fine.
You can also install Ruby 2.0 with Homebrew.
Windows
Linux
Most package managers have recent Ruby versions available. Try sudo apt-get install ruby1.9.3
or sudo yum install ruby1.9.3
. You can also use
ruby-install and
chruby.
Install the whipped-cream CLI to your computer
That's right, we're still on your computer, not your Raspberry Pi.
gem install whipped-cream
Check to make sure everything works
$ whipped-cream demo
[2013-10-11 07:59:19] INFO WEBrick 1.3.1
[2013-10-11 07:59:19] INFO ruby 1.9.3 (2013-06-27) [x86_64-darwin12.4.0]
[2013-10-11 07:59:19] INFO WEBrick::HTTPServer#start: pid=5351 port=35511
You should now be able to point your browser to http://127.0.0.1:35511 and see the demo running.
Creating Plugins
Whipped Cream creates a web page which maps HTML controls to GPIO pins.
Pins
You'll want to use the pin numbering from the BCM chip (not the actual pin number, and not the WiringPi numbers).
Raspberry Pi Rev1 | Raspberry Pi Rev2 |
---|---|
Images from HobbyTronics |
Controls
Name
Gets shown at the top of the page.
name "Garage"
Switches
Toggle a pin on or off.
switch "Light", pin: 24
Buttons
Momentarily turn a pin on for 0.25 seconds.
button "Open/Close", pin: 18
Sensors
Display something on the web page based on a pin's value.
sensor "Door", high: "Closed", low: "Open", pin: 23
Sensors can also be created with a block to show non-pin data.
sensor "Pi Uptime" do
system 'uptime'
end
Testing
- Run the tests with
rake
- Deploy to a Vagrant box with
rake vagrant:deploy
Thanks
Web UI designed by Ashton Harris.
Logo designed by Jeff Bloch.