Embedded #python

read_serial.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

""" This Module reads data from serial port
	then converts to JSON and sends to Amazon Firebase
"""

import serial
from time import sleep
from firebase import firebase
import json

arduino = serial.Serial('/dev/ttyACM0', baudrate=9600, timeout=65)
sleep(2)
arduino.flushInput()

firebase = firebase.FirebaseApplication('https://garden-c4dc3.firebaseio.com/')


def closeAndOpen(ser):
    ser.close()
    sleep(5)
    try:
        ser.open()
    except serial.SerialException as e:
        print("Trying recursice to open connection")
        print(e)
        sleep(5)
        closeAndOpen(ser)
    ser.flushInput()
    print("Connection closed and opend")
    return


def processInput(input):
    if(isValidJson(input) is True):
        data = json.loads(input)
        postToFirebase(data['type'], data)
    else:
        print("input is not valid json or desnt have type key:")
        print(input)
        postToFirebase('debug', data)
    return


def isValidJson(myjson):
    try:
        data = json.loads(myjson)
    except ValueError:
        return False
    if 'type' in data:
        return True

    return False


def postToFirebase(path, data):
    try:
        firebase.post(path, data)
        print('data successfuly posted')
        print(data)
    except Exception as e:
        print('error by upoading to firebase')
        print(e)
    return


while True:

    print("Waiting for input...")
    try:
        dataIn = arduino.readline()[:-1]
    except serial.SerialException as e:
        print("There is no new data from serial port")
        print(e)
        closeAndOpen(arduino)
    except TypeError as e:
        # Disconnect of USB->UART occured
        print("Disconnect of USB->UART occured")
        closeAndOpen(arduino)
    else:
        # Some data was received
        processInput(dataIn)