GY-21 SI7021 sensor data monitoring with Mosquitto, InfluxDB and Grafana

Projects

• mosquitto: Mosquitto Docker container configuration files
• bridge: Python script that receives MQTT data and persists those to InfluxDB
• GY-21 SI7021: Arduino sketch file for the ESP8266 and the GY-21 SI7021 that publishes sensor data to MQTT

Setup

Mosquitto + InfluxDB + Grafana

Make sure you have docker and docker-compose installed.
To install docker and docker-compose, you need to install docker-install.sh file in the project directory

chmod +x docker-install.sh && ./docker-install.sh

Set the DATA_DIR environment variable to the path where will be stored local data (e.g. in /home/ubuntu/gy21):

export DATA_DIR=/home/ubuntu/gy21

Create data directories with write access:

mkdir -p ${DATA_DIR}/mosquitto/data ${DATA_DIR}/mosquitto/log ${DATA_DIR}/influxdb ${DATA_DIR}/grafana
sudo chown -R 1883:1883 ${DATA_DIR}/mosquitto
sudo chown -R 472:472 ${DATA_DIR}/grafana

Run docker compose:

$ docker-compose up -d

Simple Way to run start.sh script in main project

chmod +x start.sh && ./start.sh

Mosquitto username and passwords are mqttuser and mqttpassword. To change these, see the Optional: Update mosquitto credentials section.

Sensor

Sensor should send data to the mosquitto broker to the following topic:
home/{peripheralName}/{temperature|humidity|battery|status}.
For example: home/GY-21-SI7021/temperature.

Arduino sketches for the ESP8266 are provided to communicate with a GY-21-SI7021 (GY-21-SI7021)
Before flashing, you need to change the WIFI_SSID, WIFI_PASSWORD, and MQTT_SERVER constants to your WiFi information and MQTT server address.

Grafana setup

• Access Grafana from http://<host ip>:3000
• Log in with user/password admin/admin
• Go to Configuration > Data Sources
• Add data source (InfluxDB)
  • Name: InfluxDB
  • URL: http://influxdb:8086
  • Database: home_db
  • User: root
  • Password: root
  • Save & Test
• Create a Dashboard
  • Add Graph Panel
  • Edit Panel
  • Data Source: InfluxDB
  • Temperature
    • FROM: [default] [temperature] WHERE [location]=[GY-21-SI7021]
    • SELECT: field(value)
    • FORMAT AS: Time series
    • Draw mode: Lines
    • Stacking & Null value: Null value [connected]
    • Left Y
      • Unit: Temperature > Celcius
    • Panel title: Temperature (°C)
  • Humidity
    • FROM: [default] [humidity] WHERE [location]=[GY-21-SI7021]
    • SELECT: field(value)
    • FORMAT AS: Time series
    • Draw mode: Lines
    • Stacking & Null value: Null value [connected]
    • Left Y
      • Unit: Misc > Humidity (%H)
    • Panel title: Humidity (%H)

Optional: Update mosquitto credentials

To change default MQTT username and password, run the following, replacing [USER] and [PASSWORD]:

$ cd mosquitto
$ echo -n "" > users
$ docker run --rm -v `pwd`/mosquitto.conf:/mosquitto/config/mosquitto.conf -v `pwd`/users:/mosquitto/config/users eclipse-mosquitto:1.5 mosquitto_passwd -b /mosquitto/config/users [USER] [PASSWORD]
$ cd -

Then, update the MQTT_USER and MQTT_PASSWORD constants in all the subdirectories, and launch docker compose again.

Alternative: Using docker manually instead of docker compose

$ cd mosquitto
$ docker run -d -p 1883:1883 -v $PWD/mosquitto.conf:/mosquitto/config/mosquitto.conf -v $PWD/users:/mosquitto/config/users -v $DATA_DIR/mosquitto/data:/mosquitto/data -v $DATA_DIR/mosquitto/log:/mosquitto/log --name mosquitto eclipse-mosquitto:1.5
$ cd -

$ docker run -d -p 8086:8086 -v $DATA_DIR/influxdb:/var/lib/influxdb --name influxdb influxdb:1.7

$ cd bridge
$ docker build -t amirmohseninia/mqttbridge .
$ docker run -d --name mqttbridge amirmohseninia/mqttbridge
$ cd -

$ docker run -d -p 3000:3000 -v $DATA_DIR/grafana:/var/lib/grafana --name=grafana grafana/grafana:5.4.3