A microservice that sends commands to connected Raspberry Pi devices.
Commands are sent in form of messages, using RabbitMQ as the message broker. Daemons on Raspberry Pi end pick these messages up and execute specific tasks on the device.
As a prerequisite, install make on your OS: https://www.gnu.org/software/make/.
Also, you'd need Python 3.x and Docker.
To start the app, run the following command in a terminal
make start
The command above uses docker-compose to run the application.
The custom Dockerfile installs all required packages (which are listed in the setup.py) and runs the nameko service from a custom shell script (run.sh).
Before running the nameko service, script confirms if RabbitMQ is running. If not, nameko service won't start.
Open an API client like Postman and do a POST request:
POST http://localhost:8001/buzzer
{ "turn_on": true }
To review the messages stacking in the queue use the RabbitMQ management portal: http://localhost:15673/#/queues
App configuration is defined in the config.yml file
Such configuration values can be accessed by importing the nameko's config package
from nameko import config
And then by using the get method of that config object.
print(config.get('AMQP_URI'))
Travis CI builds and deploys the service to Heroku.
The file travis.yml contains all definitions to build and deploy the microservice to the abovementioned cloud provider.
Travis CI automatically deploys to Heroku when build is successfull
deploy:
provider: heroku
The heroku provider uses the heroku.yml file to deploy the application, with its addons (RabbitMQ)
setup:
addons:
- plan: cloudamqp:lemur
as: BROKER
build:
docker:
web: Dockerfile-heroku
config:
APP_ENV: production
The application is deployed as a Docker container in Heroku. To build the container specifically for the cloud provider, a Dockerfile-heroku file is defined, which is slightly different from the default Dockerfile.