publish.py

import paho.mqtt.client as paho
import time
import os
from virtru_sdk import Client, LogLevel, Policy, EncryptStringParams

virtru_owner="<VIRTRU PROVIDED>"
virtru_appid="<VIRTRU PROVIDED>"
virtru_share=["user1@example.com","user2@demo.com"]
mqtt_broker="<IP/HOST of MQTT Broker>"

def encrypt_string(clear_text):
    vclient = Client(owner=virtru_owner,
                            app_id=virtru_appid)
    vclient.set_eas_url("https://api.virtru.com/accounts")
    vclient.set_kas_url("https://api.virtru.com/kas")
    vclient.set_acm_url("https://api.virtru.com/acm")

    policy = Policy()
    policy.share_with_users(virtru_share)
    policy.expire_in_days(10)

    string_params = EncryptStringParams(clear_text)
    string_params.set_policy(policy)
    (policy_id, tdf_data) = vclient.encrypt_string(encrypt_string_params=string_params)
    return tdf_data

def measure_temp():
    temp = os.popen("vcgencmd measure_temp").readline()
    return (temp.replace("temp=","")).replace("'C",'').strip()
    #return "0"

client = paho.Client()
client.connect(mqtt_broker, 1883)
client.loop_start()

while True:
    temperature = measure_temp()
    ticks = str(time.time())
    print(f"{ticks} Temp: {temperature}")
    enc_temp = encrypt_string(str(f"{ticks} {temperature}"))
    (rc, mid) = client.publish("sensor/temperature", enc_temp, qos=1)
    time.sleep(1)