flectra/addons/hw_scanner/controllers/main.py
2018-01-16 02:34:37 -08:00

241 lines
8.1 KiB
Python

# -*- coding: utf-8 -*-
# Part of Odoo, Flectra. See LICENSE file for full copyright and licensing details.
import logging
import time
from os import listdir
from os.path import join
try:
from queue import Queue, Empty
except ImportError:
from Queue import Queue, Empty # pylint: disable=deprecated-module
from select import select
from threading import Thread, Lock
from flectra import http
from flectra.addons.hw_proxy.controllers import main as hw_proxy
_logger = logging.getLogger(__name__)
try:
import evdev
except ImportError:
_logger.error('Flectra module hw_scanner depends on the evdev python module')
evdev = None
class ScannerDevice():
def __init__(self, path):
self.evdev = evdev.InputDevice(path)
self.evdev.grab()
self.barcode = []
self.shift = False
class Scanner(Thread):
def __init__(self):
Thread.__init__(self)
self.lock = Lock()
self.status = {'status':'connecting', 'messages':[]}
self.input_dir = '/dev/input/by-id/'
self.open_devices = []
self.barcodes = Queue()
self.keymap = {
2: ("1","!"),
3: ("2","@"),
4: ("3","#"),
5: ("4","$"),
6: ("5","%"),
7: ("6","^"),
8: ("7","&"),
9: ("8","*"),
10:("9","("),
11:("0",")"),
12:("-","_"),
13:("=","+"),
# 14 BACKSPACE
# 15 TAB
16:("q","Q"),
17:("w","W"),
18:("e","E"),
19:("r","R"),
20:("t","T"),
21:("y","Y"),
22:("u","U"),
23:("i","I"),
24:("o","O"),
25:("p","P"),
26:("[","{"),
27:("]","}"),
# 28 ENTER
# 29 LEFT_CTRL
30:("a","A"),
31:("s","S"),
32:("d","D"),
33:("f","F"),
34:("g","G"),
35:("h","H"),
36:("j","J"),
37:("k","K"),
38:("l","L"),
39:(";",":"),
40:("'","\""),
41:("`","~"),
# 42 LEFT SHIFT
43:("\\","|"),
44:("z","Z"),
45:("x","X"),
46:("c","C"),
47:("v","V"),
48:("b","B"),
49:("n","N"),
50:("m","M"),
51:(",","<"),
52:(".",">"),
53:("/","?"),
# 54 RIGHT SHIFT
57:(" "," "),
}
def lockedstart(self):
with self.lock:
if not self.isAlive():
self.daemon = True
self.start()
def set_status(self, status, message = None):
if status == self.status['status']:
if message != None and message != self.status['messages'][-1]:
self.status['messages'].append(message)
else:
self.status['status'] = status
if message:
self.status['messages'] = [message]
else:
self.status['messages'] = []
if status == 'error' and message:
_logger.error('Barcode Scanner Error: '+message)
elif status == 'disconnected' and message:
_logger.info('Disconnected Barcode Scanner: %s', message)
def get_devices(self):
try:
if not evdev:
return []
if not os.path.isdir(self.input_dir):
return []
new_devices = [device for device in listdir(self.input_dir)
if join(self.input_dir, device) not in [dev.evdev.fn for dev in self.open_devices]]
scanners = [device for device in new_devices
if (('kbd' in device) and ('keyboard' not in device.lower()))
or ('barcode' in device.lower()) or ('scanner' in device.lower())]
for device in scanners:
_logger.debug('opening device %s', join(self.input_dir,device))
self.open_devices.append(ScannerDevice(join(self.input_dir,device)))
if self.open_devices:
self.set_status('connected','Connected to '+ str([dev.evdev.name for dev in self.open_devices]))
else:
self.set_status('disconnected','Barcode Scanner Not Found')
return self.open_devices
except Exception as e:
self.set_status('error',str(e))
return []
def release_device(self, dev):
self.open_devices.remove(dev)
def get_barcode(self):
""" Returns a scanned barcode. Will wait at most 5 seconds to get a barcode, and will
return barcode scanned in the past if they are not older than 5 seconds and have not
been returned before. This is necessary to catch barcodes scanned while the POS is
busy reading another barcode
"""
self.lockedstart()
while True:
try:
timestamp, barcode = self.barcodes.get(True, 5)
if timestamp > time.time() - 5:
return barcode
except Empty:
return ''
def get_status(self):
self.lockedstart()
return self.status
def _get_open_device_by_fd(self, fd):
for dev in self.open_devices:
if dev.evdev.fd == fd:
return dev
def run(self):
""" This will start a loop that catches all keyboard events, parse barcode
sequences and put them on a timestamped queue that can be consumed by
the point of sale's requests for barcode events
"""
self.barcodes = Queue()
barcode = []
shift = False
devices = None
while True: # barcodes loop
devices = self.get_devices()
try:
while True: # keycode loop
r,w,x = select({dev.fd: dev for dev in [d.evdev for d in devices]},[],[],5)
if len(r) == 0: # timeout
break
for fd in r:
device = self._get_open_device_by_fd(fd)
if not evdev.util.is_device(device.evdev.fn):
_logger.info('%s disconnected', str(device.evdev))
self.release_device(device)
break
events = device.evdev.read()
for event in events:
if event.type == evdev.ecodes.EV_KEY:
# _logger.debug('Evdev Keyboard event %s',evdev.categorize(event))
if event.value == 1: # keydown events
if event.code in self.keymap:
if device.shift:
device.barcode.append(self.keymap[event.code][1])
else:
device.barcode.append(self.keymap[event.code][0])
elif event.code == 42 or event.code == 54: # SHIFT
device.shift = True
elif event.code == 28: # ENTER, end of barcode
_logger.debug('pushing barcode %s from %s', ''.join(device.barcode), str(device.evdev))
self.barcodes.put( (time.time(),''.join(device.barcode)) )
device.barcode = []
elif event.value == 0: #keyup events
if event.code == 42 or event.code == 54: # LEFT SHIFT
device.shift = False
except Exception as e:
self.set_status('error',str(e))
scanner_thread = None
if evdev:
scanner_thread = Scanner()
hw_proxy.drivers['scanner'] = scanner_thread
class ScannerDriver(hw_proxy.Proxy):
@http.route('/hw_proxy/scanner', type='json', auth='none', cors='*')
def scanner(self):
return scanner_thread.get_barcode() if scanner_thread else None