Strichliste.org Barcodescanner for raspberry pi

barcodescanner.py

# ----------------------------------------------------------------------------
# "THE BEER-WARE LICENSE" (Revision 42):
# <github@jko.dev> wrote this file. As long as you retain this notice you
# can do whatever you want with this stuff. If we meet some day, and you think
# this stuff is worth it, you can buy me a beer in return. Jannik Kolodziej
# ----------------------------------------------------------------------------
import time
from selenium import webdriver
from selenium.webdriver.common.keys import Keys
import os
import re
from pyzbar import pyzbar
import picamera
from io import BytesIO
from PIL import Image


def search_barcode():
    stream = BytesIO()
    camera.capture(stream, format='png')
    stream.seek(0)
    frame = Image.open(stream)
    barcodes = pyzbar.decode(frame)

    for barcode in barcodes:
        type = barcode.type
        data = barcode.data.decode("utf8")

        if type != "EAN13":
            continue
        if (len(data) != 13) or (not data.isdigit()):
            continue

        print("[INFO] found barcode of type {}, content is: {}".format(type, data))
        return data
    return None


def enter_barcode(data):
    driver.find_element_by_xpath('//body').send_keys(data)
    driver.find_element_by_xpath('//body').send_keys(Keys.ENTER)


user_url_pattern = re.compile('.*#!/user/\d+')

os.environ["LANG"] = "en_US.UTF-8"
os.environ["DISPLAY"] = ":0"

chrome_options = webdriver.ChromeOptions()
chrome_options.add_argument("--kiosk")
chrome_options.add_argument("--start-maximized")
chrome_options.add_argument("--disable-infobars")
chrome_options.add_argument("--user-data-dir=~/.selenium")
chrome_options.add_argument("--app https://demo.strichliste.org")
chrome_options.add_argument("--google-base-url=https://demo.strichliste.org")

print("[INFO] starting webbrowser")
driver = webdriver.Chrome(chrome_options=chrome_options)
driver.get("https://demo.strichliste.org")

print("[INFO] starting video stream")
with picamera.PiCamera(resolution=(800, 450), framerate=30) as camera:
    time.sleep(2.0)
    print("[INFO] entering main loop")
    last_valid_barcode = None
    while True:
        if user_url_pattern.match(driver.current_url):
            barcode = search_barcode()
            if barcode is not None:
                if last_valid_barcode == barcode:
                    print("[INFO] ignoring barcode to avoid double payment")
                    continue
                last_valid_barcode = barcode
                time.sleep(1.0)
                enter_barcode(barcode)
            else:
                last_valid_barcode = None
                continue
        time.sleep(0.5)