Cameteo/cameteo-interface/mqtt2epaper.py

# -*- coding: utf-8 -*-
"""
Display data from MQTT broker on ePaper screen

@author: arofarn
"""

###########
# IMPORTS #
###########

from cameteo_conf import *
import paho.mqtt.client as mqtt
from spidev import SpiDev
import EPD_driver
import json
import netifaces

mqtt_client_id = "epaper_display"

#############
# CALLBACKS #
#############

#Callback pour la connection au MQTT : souscriptions aux topics
def on_connect(client, userdata, flags, rc):
    print(mqtt.connack_string(rc))
    if rc == 0:
        print("Subscribing to %s ..." % mqtt_topic)
        client.subscribe([(mqtt_topic, 0),
                          (camera_mqtt_topic + "/#", 0)]
                        )
        print("OK")
    
#Callback de gestion des messages arrivant au MQTT :
#  affichage et enregistrement en base de données
def on_message(client, userdata, msg):
    top=msg.topic[len(mqtt_topic)-1:].strip()
    subtopics = top.split("/")
    
    if subtopics[0] == "AdaBME280_1":
        payload = msg.payload.decode()
        print(payload)
        val = json.loads(payload)
        
        #Test présence et cohérence de la valeur        
        try:
            val['value'] = float(val['value'] )
        except:
            print("Value error: {}".format(val['value']))
            val['value'] = float('nan')
        
        #Gestion du symbole des degrés parfois difficile pour certaines sources
        #val['unit'] = val['unit'].replace('deg', '°')
        
        #Affichage des données
        coord_type = { 'TA' : 33,
                       'HR' : 49,
                       'SLPA' : 65
                       }
        if val['type'] in coord_type:
            disp.Dis_String(125, coord_type[val['type']], "{} {}  ".format(val['value'], val['unit']), 16)
        
#Callback managing date and time from MQTT broker 
def on_message_date(client, userdata, msg):
    payload = msg.payload.decode()
    print("Date : " + payload)
    try:
        d = datetime.strptime(payload, "%H:%M:%S %d/%m/%Y")
        disp.Dis_String(0, 17, datetime.strftime(d + TimeZone.utcoffset(None), "%d/%m/%Y %H:%M:%S"), 16)
    except:
        disp.Dis_String(0, 17, payload, 16)

#Update display with info from camera (camera shooting new photo or name of the
# last photo)
def on_message_camera(client, userdata, msg):
    pl = msg.payload.decode()
    print("{} : {} ({})".format(msg.topic, pl, type(pl)))    
    if pl == "1" and msg.topic == camera_mqtt_topic + "/shooting" :
        disp.Dis_String(0, 105, "Shooting photo...              ", 16)
    if msg.topic == camera_mqtt_topic + "/last_photo":
        disp.Dis_String(0, 105, "Last: " + pl, 16)
        
#Callback de déconnexion au broker MQTT
def on_disconnect(client, userdata, msg):
    if msg != 0:
        print("Déconnexion imprévu : %s" % msg)
    exit()
    
########
# Main #
########

#init and Clear full screen
bus = 0 
device = 0
disp = EPD_driver.EPD_driver(spi=SpiDev(bus, device))

print("Start display...")
disp.Dis_Clear_full()
disp.Dis_Clear_part()
print("OK")

#disp.Dis_String(0, 0, "{} | {}".format(socket.gethostname(), netifaces.ifaddresses('wlan0')[2][0]['addr']), 12)
disp.Dis_String(0, 0,  "IPv4         : {}".format(netifaces.ifaddresses('wlan0')[2][0]['addr']), 16)
disp.Dis_String(0, 33, "Temperature  : ", 16)
disp.Dis_String(0, 49, "Humidity     : ", 16)
disp.Dis_String(0, 65, "Sea Pression : ", 16)

#Connect to MQTT broker and loop...
mqtt_client = mqtt.Client(mqtt_client_id, clean_session=True)
mqtt_client.username_pw_set(mqtt_user, mqtt_pass)
mqtt_client.on_connect = on_connect
mqtt_client.on_message = on_message
mqtt_client.on_disconnect = on_disconnect

mqtt_client.message_callback_add("huzzah0/NTP/date", on_message_date)
mqtt_client.message_callback_add(camera_mqtt_topic + "/#", on_message_camera)

print(mqtt_host + ":" + str(mqtt_port))
mqtt_client.connect(mqtt_host, int(mqtt_port), 60)

mqtt_client.loop_forever()