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Smart Cities Group Project

Development Setup

Follow the sections for embedded and backend to setup a development environment for the CMB device and the backend, respectively.

Network Temporary

For now to connect the CMB device to a network turn your computer into a wifi hotspot with the following credentials: SSID: test, Password: test12345. This is only temporary until we have a better solution for provisioning the device.

Embedded

Power the ESP32 device and open a Serial Monitor (for example PlatformIO's built-in Serial Monitor in VSCode) with the baud rate set to 115200. You should see the device booting up and trying to connect to the wifi network. If it connects successfully you should see the IP address it received from the network. If it fails to connect it will retry every 60 seconds.

After connecting to the network it will try to connect to the MQTT broker on the backend. If it connects successfully it will start sending sensor data every 10 seconds. If it fails to connect it will retry every 60 seconds.

Backend

Environment variables

See security / environment variables for an explanation of all environment variables.

For a development setup you need to create your own .env file which you can copy from .env.example. You only need to provide your own secrets, which is described in the security file.

Docker

Every service is defined in the docker-compose.yml file. During development you will need to run the database, mqtt-broker, and optionally mqttx a web client for viewing / debugging mqtt events in a docker container.

To run those services on your local machine:

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docker compose up -d mariadb mosquitto mqttx

If you have changed the seed.sql file or want to reset the database you can do this by executing:

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docker compose down
rm -rf ./docker/config/mariadb/*
docker compose up -d

To view data from sensors you can execute (example for SHT41 sensor):

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docker exec -it cmb-mariadb sh -c 'mariadb -uroot -p"${MARIADB_PASSWORD}" "${MARIADB_DATABASE}" -e "SELECT * FROM SHT41;"'

Backend API

The NodeJS docker service is only for production. To run the API on your local machine you need to install the npm dependencies and start it.

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cd web
npm install
npm run dev

MQTTX (mqtt event viewer)

You can easily view and send MQTT events using the MQTTX web client. Go to http://localhost:8080 in a web browser and use this configuration:

MQTTX

  • Name: whatever you want
  • Host: ws:// localhost
  • Port: 9001
  • Client ID: doesn't matter whatever is already filled in
  • Path: /mqtt

And press Connect.

See the MQTTX docs for more information.

Database

You can connect to the datbase with any database explorer using your credentials. The database is seeded with the data/seed.sql file. If you want to reseed the database, see the section above about Docker.

And replace the UPPERCASE variables with your env variables.

Database explorer

It is useful to install a database explorer if you want to view the database show. I recommend DBBeaver