If you have a spare Raspberry Pi sitting around (and who doesn't) or are seeking an excuse to buy that newly released
Model B+ model with 4 USB ports, then have you considered combining it with a
Siren of Shame to hassle your build breaking office mates whether you're at the office or not? If that sounds good this article is for you.
Getting Started
You'll need a Siren of Shame
device and a Raspberry Pi that's running and connected to the Internet. Element14 has a great
getting started set of videos if you're completely new to Raspberry Pi. This post used the Raspbian OS, but theoretically it shouldn't matter what OS you use.
libusb
Libusb provides an API for applications to interface with USB devices, including Human Interface Devices (HID) such as the Siren of Shame. To install libusb use apt-get (the universal Linux installer).
If this is a new Raspberry Pi with a fresh install of Linux then you will need to update your list of available packages with
sudo apt-get update
Follow that up with:
sudo apt-get install libusb-dev
You should now be able to run lsusb from the command line to list devices. Plug in a Siren of Shame, run lsusb, and you should get a device with an id of 16d0:0646 called GrauTec. It should look like:
lsusb
...
Bus 001 Device 011: ID 16d0:0646 GrauTec
If your device doesn't show up, it could be an issue with the cable.
Andy Lowry, who has an excellent blog post where he lights up his siren of shame when freight trains are near, reports that he had to try several cables before finding one that worked.
Node.js
Thanks exclusively to
Joe Ferner and his
node-sos-device project we have a solution for connecting Siren of Shame's to linux using Node.js. To install Node.js it should be as easy as:
sudo apt-get install nodejs
sudo apt-get install npm
Incidentally, rather than using
node-sos-device directly, we will be using the higher-level
node-sos-client, which knows how to monitor Jenkins and Bamboo CI servers.
Node-sos-client
If you haven't configured your device to work with git you could do it the right way with SSH and
generate an ssh key or you could just:
git clone https://github.com/AutomatedArchitecture/node-sos-client.git
and
cd node-sos-client
Next you'll need to download all Node dependencies. If this is a fresh install you'll need to tell the node package manager (npm) where to retrieve dependencies from:
npm config set registry http://registry.npmjs.org/
Now you can install all dependencies for node-sos-client by running
npm install
Upgrading Node
For some fortunate users (
Andy Lowry for one) installing node via apt-get works fine. If, however, you get an error about node being out of date you'll have to uninstall, download, and update your path.
First, to uninstall the old version of node:
sudo apt-get remove npm
sudo apt-get remove node
No download and unpack:
cd ~
wget http://nodejs.org/dist/v0.10.2/node-v0.10.2-linux-arm-pi.tar.gz
tar -xvzf node-v0.10.2-linux-arm-pi.tar.gz
To add it to your path
nano .bashrc
And add the following two lines at the bottom:
NODE_JS_HOME=/home/pi/node-v0.10.2-linux-arm-pi
PATH=$PATH:$NODE_JS_HOME/bin
If you restart your command prompt and type node --version you should get v0.10.2.
Now retry npm install.
cd node-sos-client
npm install
And you should be good to go.
Running node-sos-client
First make a copy of the default configuration file:
cp config.json.example config.json
We'll configure it correctly later. Next pick up the dependency on node-sos-device by running:
npm install sos-device
To run the app you should be able to run
sudo node build/sos-client.js
However, if you had to install node with the wget method, then you'll need to run
sudo $NODE_JS_HOME/bin/node build/sos-client.js
If you're lucky you'll see the app print out the device stats as json and a configuration error, something like:
deviceInfo: { version: 1,
hardwareType: 1,
hardwareVersion: 1,
externalMemorySize: 0,
audioMode: 0,
audioPlayDuration: 0,
ledMode: 0,
ledPlayDuration: 0,
ledPatterns:
[ { id: 2, name: 'On/Off' },
{ id: 3, name: 'Fade' },
{ id: 4, name: 'Chase' },
{ id: 5, name: 'Fade Chase' } ],
audioPatterns:
[ { id: 1, name: 'Sad Trombone' },
{ id: 2, name: 'Ding!' },
{ id: 3, name: 'Plunk' } ] }
Failed to poll: bamboo0 { [Error: getaddrinfo ENOTFOUND] code: 'ENOTFOUND', errno: 'ENOTFOUND', syscall: 'getaddrinfo' }
However, if you have a cable that doesn't work well, or are connecting through a non-powered USB hub you may see:
Error: usb_detach_kernel_driver_np: -113 could not detach kernel driver from interface 0: No route to host
In this case try experimenting with the way you connect the device to the Pi.
Configuring the Connection
Today node-sos-client can connect to two CI servers: Bamboo, and Jenkins. To connect to Jenkins update the config file to something like:
{
"builds": [
{
"type": "jenkins",
"config": {
"url": "http://127.0.0.1/jenkins/api/json/",
"username": "[username]",
"password": "[password]"
}
}
]
}
And you're done. With any luck running sudo node build/sos-client.js will light the siren and sound the speaker on initial connection, and whenever the build breaks.
Summary
And now you too can terrorize your build breaking colleagues, even when you're not at the office. Enjoy!
