kegnet client

kegnet-client

kegnet-client is the KegNet client temperature and pour transmitter daemon.

Versions

There are 2 versions, in separate branches in GitHub:

• master branch is the current, which uses REST and PKI and send data directly to KegNet servers
• xively branch is older/alternate, which uses Xively a 3rd party service provider

Function

• Reads temperature from W1 device
• Transmits signed temperature at regular intervals (pings)
• Monitors /usr/share/kegnet-client/spool for new .pour files
• Transmits signed our data
• Deletes .pour file upon successful transmission

Code

• Written in Python, code at client.py
• Uses ConfigParser to read configuration
• Uses Pyinotify to monitor directory for new files
• Uses M2Crypto to load private key and sign data
• Uses base64 to convert signature bytes to ascii
• Uses Requests to communicate over HTTPS to KegNet servers
• Uses syslog library to write logs

Operation

• Executable located at /usr/share/kegnet-client/lib/client.py
• Started and managed as a daemon by systemd
• Service configuration file is /usr/share/kegnet-client/service/kegnet-client.service
• .service file is linked into /etc/systemd/system/multi-user.target.wants to start up on multi-user run level
• To manually start kegnet-client execute /usr/share/kegnet-client/start-kegnet-client or systemctl start kegnet-client.service
• To manually stop kegnet-client execute /usr/share/kegnet/stop-kegnet-client or systemctl stop kegnet-client.service

Configuration

• /usr/share/kegnet-client/conf/privkey.pem is the client's private key file
• Reads configuration from /usr/share/kegnet-client/conf/client.conf
• /usr/share/kegnet-client/conf/client.conf contains 2 parameters: uuid and serviceBaseURL
• uuid is the KegNet client's unique UUID, which identifies it to the KegNet servers
• serviceBaseURL is the URL to the KegNet REST API

Output

• Logs using syslog to /var/log/user.log