python-escpos/escpos/printer.py

#!/usr/bin/python
""" This module contains the implentations of abstract base class :py:class:`Escpos`.

:author: `Manuel F Martinez <manpaz@bashlinux.com>`_ and others
:organization: Bashlinux and `python-escpos <https://github.com/python-escpos>`_
:copyright: Copyright (c) 2012 Bashlinux
:license: GNU GPL v3
"""

import usb.core
import usb.util
import serial
import socket

from .escpos import *
from .constants import *
from .exceptions import *


class Usb(Escpos):
    """ USB printer

    This class describes a printer that natively speaks USB.
    """

    def __init__(self, idVendor, idProduct, interface=0, in_ep=0x82, out_ep=0x01, *args, **kwargs):
        """
        :param idVendor: Vendor ID
        :param idProduct: Product ID
        :param interface: USB device interface
        :param in_ep: Input end point
        :param out_ep: Output end point
        """
        Escpos.__init__(self, *args, **kwargs)
        self.idVendor  = idVendor
        self.idProduct = idProduct
        self.interface = interface
        self.in_ep = in_ep
        self.out_ep = out_ep
        self.open()

    def open(self):
        """ Search device on USB tree and set it as escpos device """
        self.device = usb.core.find(idVendor=self.idVendor, idProduct=self.idProduct)
        if self.device is None:
            print("Cable isn't plugged in")

        check_driver = None

        try:
            check_driver = self.device.is_kernel_driver_active(0)
        except NotImplementedError:
            pass

        if check_driver is None or check_driver:
            try:
                self.device.detach_kernel_driver(0)
            except usb.core.USBError as e:
                if check_driver is not None:
                    print("Could not detatch kernel driver: %s" % str(e))

        try:
            self.device.set_configuration()
            self.device.reset()
        except usb.core.USBError as e:
            print("Could not set configuration: %s" % str(e))

    def _raw(self, msg):
        """ Print any command sent in raw format

        :param msg: arbitrary code to be printed
        """
        self.device.write(self.out_ep, msg, self.interface)

    def __del__(self):
        """ Release USB interface """
        if self.device:
            usb.util.dispose_resources(self.device)
        self.device = None


class Serial(Escpos):
    """ Serial printer

    This class describes a printer that is connected by serial interface.
    """

    def __init__(self, devfile="/dev/ttyS0", baudrate=9600, bytesize=8, timeout=1,
                 parity=serial.PARITY_NONE, stopbits=serial.STOPBITS_ONE,
                 xonxoff=False, dsrdtr=True, *args, **kwargs):
        """

        :param devfile:  Device file under dev filesystem
        :param baudrate: Baud rate for serial transmission
        :param bytesize: Serial buffer size
        :param timeout:  Read/Write timeout
        :param parity:   Parity checking
        :param stopbits: Number of stop bits
        :param xonxoff:  Software flow control
        :param dsrdtr:   Hardware flow control (False to enable RTS/CTS)
        """
        Escpos.__init__(self, *args, **kwargs)
        self.devfile  = devfile
        self.baudrate = baudrate
        self.bytesize = bytesize
        self.timeout  = timeout
        self.parity = parity
        self.stopbits = stopbits
        self.xonxoff = xonxoff
        self.dsrdtr = dsrdtr

        self.open()

    def open(self):
        """ Setup serial port and set is as escpos device """
        self.device = serial.Serial(port=self.devfile, baudrate=self.baudrate,
                                    bytesize=self.bytesize, parity=self.parity,
                                    stopbits=self.stopbits, timeout=self.timeout,
                                    xonxoff=self.xonxoff, dsrdtr=self.dsrdtr)

        if self.device is not None:
            print("Serial printer enabled")
        else:
            print("Unable to open serial printer on: %s" % self.devfile)

    def _raw(self, msg):
        """ Print any command sent in raw format

        :param msg: arbitrary code to be printed
        """
        self.device.write(msg)

    def __del__(self):
        """ Close Serial interface """
        if self.device is not None:
            self.device.close()


class Network(Escpos):
    """ Network printer

    This class is used to attach to a networked printer. You can also use this in order to attach to a printer that
    is forwarded with `netcat`.
    """

    def __init__(self, host, port=9100, *args, **kwargs):
        """

        :param host : Printer's hostname or IP address
        :param port : Port to write to
        """
        Escpos.__init__(self, *args, **kwargs)
        self.host = host
        self.port = port
        self.open()

    def open(self):
        """ Open TCP socket and set it as escpos device """
        self.device = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        self.device.connect((self.host, self.port))

        if self.device is None:
            print("Could not open socket for %s" % self.host)

    def _raw(self, msg):
        """ Print any command sent in raw format

        :param msg: arbitrary code to be printed
        """
        self.device.send(msg)

    def __del__(self):
        """ Close TCP connection """
        self.device.close()


class File(Escpos):
    """ Generic file printer

    This class is used for parallel port printer or other printers that are directly attached to the filesystem.
    Note that you should stay away from using USB-to-Parallel-Adapter since they are unreliable
    and produce arbitrary errors.
    """

    def __init__(self, devfile="/dev/usb/lp0", *args, **kwargs):
        """

        :param devfile : Device file under dev filesystem
        """
        Escpos.__init__(self, *args, **kwargs)
        self.devfile = devfile
        self.open()

    def open(self):
        """ Open system file """
        self.device = open(self.devfile, "wb")

        if self.device is None:
            print("Could not open the specified file %s" % self.devfile)

    def flush(self):
        """ Flush printing content """
        self.device.flush()

    def _raw(self, msg):
        """ Print any command sent in raw format

        :param msg: arbitrary code to be printed
        """
        if type(msg) is str:
            self.device.write(msg.encode());
        else:
            self.device.write(msg);

    def __del__(self):
        """ Close system file """
        self.device.close()