A little api for the UV sensor (veml6075), and the CO2 / VOC sensor (sgp30)

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Just a little bit of code so you can remotely get values from these sensors. I have them connected together using the Breakout Garden on a Pi Zero.

You’ll need flask installed, sudo apt install python-flask if you haven’t. Otherwise it just uses the python modules you have already from installing the devices.

You can test it with:

curl -s [IP of the Pi with the sensors]:5000/sensor/co2_voc

and

curl -s [IP of the Pi with the sensors]:5000/sensor/uv_raw

curl -s [IP of the Pi with the sensors]:5000/sensor/uv_index

  #!/usr/bin/env python
from flask import Flask, jsonify, make_response
import veml6075
from sgp30 import SGP30
import smbus
import sys

bus = smbus.SMBus(1)
sgp30 = SGP30()

# Create VEML6075 instance and set up
uv_sensor = veml6075.VEML6075(i2c_dev=bus)
uv_sensor.set_shutdown(False)
uv_sensor.set_high_dynamic_range(False)
uv_sensor.set_integration_time('100ms')

def crude_progress_bar():
    sys.stdout.write('.')
    sys.stdout.flush()

sgp30.start_measurement(crude_progress_bar)

app = Flask(__name__)

@app.route('/sensor/uv_raw', methods=['GET'])
def uv_raw_readings():
    uva, uvb = uv_sensor.get_measurements()
    return jsonify({'uva_raw' : uva, 'uvb_raw' : uvb})

@app.route('/sensor/uv_index', methods=['GET'])
def uv_index_readings():
    uva, uvb = uv_sensor.get_measurements()
    uv_comp1, uv_comp2 = uv_sensor.get_comparitor_readings()
    uv_indices = uv_sensor.convert_to_index(uva, uvb, uv_comp1, uv_comp2)

    return jsonify({'uva_index' : float(round(uv_indices[0],3)), 'uvb_index' : float(round(uv_indices[1], 3))})

@app.route('/sensor/co2_voc', methods=['GET'])
def co2_voc():
    split_result = str(sgp30.get_air_quality()).split(' ')
    first = 0
    co2 = 0
    voc = 0
    for i in split_result:
        if i.isdigit() and first == 0:
            co2 = i
            first = 1
        if i.isdigit() and first == 1:
            voc = i
    return jsonify({'CO2' : co2, 'VOC' : voc})

@app.errorhandler(404)
def not_found(error):
    return make_response(jsonify({'error': 'Not found'}), 404)

if __name__ == '__main__':
    app.run(host='0.0.0.0', debug=False)

I have it feeding the data into my Home Assistant, and here’s how those entries look:

## UV Sensor - Raspberry Pi Breakout

  - platform: rest
    name: UV Raw Values
    json_attributes:
      - uva_raw
      - uvb_raw
    resource: http://192.xxx.xxx.xxx:5000/sensor/uv_raw

  - platform: rest
    name: UV Index Values
    json_attributes:
      - uva_index
      - uvb_index
    resource: http://192.xxx.xxx.xxx:5000/sensor/uv_index
    
  - platform: template
    sensors:
      uva_index_reading:
         friendly_name: UV A Index
         value_template: '{{ states.sensor.uv_index_values.attributes["uva_index"] }}'    

  - platform: template
    sensors:
      uvb_index_reading:
         friendly_name: UV B Index
         value_template: '{{ states.sensor.uv_index_values.attributes["uvb_index"] }}'  


## CO2 & VOC Sensor - Raspberry Pi Breakout

  - platform: rest
    name: CO2 and VOC levels
    json_attributes:
      - CO2
      - VOC
    resource: http://192.xxx.xxx.xxx:5000/sensor/co2_voc


  - platform: template
    sensors:
      co2_levels:
         friendly_name: CO2 Levels
         value_template: '{{ states.sensor.co2_and_voc_levels.attributes["CO2"] }}'
         unit_of_measurement: ppm

  - platform: template
    sensors:
      voc_levels:
         friendly_name: VOC Levels
         value_template: '{{ states.sensor.co2_and_voc_levels.attributes["VOC"] }}'
         unit_of_measurement: ppb