#!/usr/bin/python
# -*- coding: utf-8 -*-
""" Main class
This module contains the 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
"""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
import qrcode
import textwrap
from .constants import *
from .exceptions import *
from abc import ABCMeta, abstractmethod # abstract base class support
from escpos.image import EscposImage
@six.add_metaclass(ABCMeta)
[docs]class Escpos(object):
""" ESC/POS Printer object
This class is the abstract base class for an esc/pos-printer. The printer implementations are children of this
class.
"""
device = None
codepage = None
def __init__(self, columns=32):
""" Initialize ESCPOS Printer
:param columns: Text columns used by the printer. Defaults to 32."""
self.columns = columns
def __del__(self):
""" call self.close upon deletion """
self.close()
@abstractmethod
def _raw(self, msg):
""" Sends raw data to the printer
This function has to be individually implemented by the implementations.
:param msg: message string to be sent to the printer
:type msg: bytes
"""
pass
[docs] def image(self, img_source, high_density_vertical=True, high_density_horizontal=True, impl="bitImageRaster"):
""" Print an image
You can select whether the printer should print in high density or not. The default value is high density.
When printing in low density, the image will be stretched.
Esc/Pos supplies several commands for printing. This function supports three of them. Please try to vary the
implementations if you have any problems. For example the printer `IT80-002` will have trouble aligning
images that are not printed in Column-mode.
The available printing implementations are:
* `bitImageRaster`: prints with the `GS v 0`-command
* `graphics`: prints with the `GS ( L`-command
* `bitImageColumn`: prints with the `ESC *`-command
:param img_source: PIL image or filename to load: `jpg`, `gif`, `png` or `bmp`
:param high_density_vertical: print in high density in vertical direction *default:* True
:param high_density_horizontal: print in high density in horizontal direction *default:* True
:param impl: choose image printing mode between `bitImageRaster`, `graphics` or `bitImageColumn`
"""
im = EscposImage(img_source)
if impl == "bitImageRaster":
# GS v 0, raster format bit image
density_byte = (0 if high_density_horizontal else 1) + (0 if high_density_vertical else 2)
header = GS + b"v0" + six.int2byte(density_byte) + self._int_low_high(im.width_bytes, 2) + self._int_low_high(im.height, 2)
self._raw(header + im.to_raster_format())
if impl == "graphics":
# GS ( L raster format graphics
img_header = self._int_low_high(im.width, 2) + self._int_low_high(im.height, 2)
tone = b'0'
colors = b'1'
ym = six.int2byte(1 if high_density_vertical else 2)
xm = six.int2byte(1 if high_density_horizontal else 2)
header = tone + xm + ym + colors + img_header
raster_data = im.to_raster_format()
self._image_send_graphics_data(b'0', b'p', header + raster_data)
self._image_send_graphics_data(b'0', b'2', b'')
if impl == "bitImageColumn":
# ESC *, column format bit image
density_byte = (1 if high_density_horizontal else 0) + (32 if high_density_vertical else 0)
header = ESC + b"*" + six.int2byte(density_byte) + self._int_low_high(im.width, 2)
outp = [ESC + b"3" + six.int2byte(16)] # Adjust line-feed size
for blob in im.to_column_format(high_density_vertical):
outp.append(header + blob + b"\n")
outp.append(ESC + b"2") # Reset line-feed size
self._raw(b''.join(outp))
def _image_send_graphics_data(self, m, fn, data):
"""
Wrapper for GS ( L, to calculate and send correct data length.
:param m: Modifier//variant for function. Usually '0'
:param fn: Function number to use, as byte
:param data: Data to send
"""
header = self._int_low_high(len(data) + 2, 2)
self._raw(GS + b'(L' + header + m + fn + data)
[docs] def qr(self, content, ec=QR_ECLEVEL_L, size=3, model=QR_MODEL_2, native=False):
""" Print QR Code for the provided string
:param content: The content of the code. Numeric data will be more efficiently compacted.
:param ec: Error-correction level to use. One of QR_ECLEVEL_L (default), QR_ECLEVEL_M, QR_ECLEVEL_Q or
QR_ECLEVEL_H.
Higher error correction results in a less compact code.
:param size: Pixel size to use. Must be 1-16 (default 3)
:param model: QR code model to use. Must be one of QR_MODEL_1, QR_MODEL_2 (default) or QR_MICRO (not supported
by all printers).
:param native: True to render the code on the printer, False to render the code as an image and send it to the
printer (Default)
"""
# Basic validation
if ec not in [QR_ECLEVEL_L, QR_ECLEVEL_M, QR_ECLEVEL_H, QR_ECLEVEL_Q]:
raise ValueError("Invalid error correction level")
if not 1 <= size <= 16:
raise ValueError("Invalid block size (must be 1-16)")
if model not in [QR_MODEL_1, QR_MODEL_2, QR_MICRO]:
raise ValueError("Invalid QR model (must be one of QR_MODEL_1, QR_MODEL_2, QR_MICRO)")
if content == "":
# Handle edge case by printing nothing.
return
if not native:
# Map ESC/POS error correction levels to python 'qrcode' library constant and render to an image
if model != QR_MODEL_2:
raise ValueError("Invalid QR model for qrlib rendering (must be QR_MODEL_2)")
python_qr_ec = {
QR_ECLEVEL_H: qrcode.constants.ERROR_CORRECT_H,
QR_ECLEVEL_L: qrcode.constants.ERROR_CORRECT_L,
QR_ECLEVEL_M: qrcode.constants.ERROR_CORRECT_M,
QR_ECLEVEL_Q: qrcode.constants.ERROR_CORRECT_Q
}
qr_code = qrcode.QRCode(version=None, box_size=size, border=1, error_correction=python_qr_ec[ec])
qr_code.add_data(content)
qr_code.make(fit=True)
qr_img = qr_code.make_image()
im = qr_img._img.convert("RGB")
# Convert the RGB image in printable image
self.image(im)
return
# Native 2D code printing
cn = b'1' # Code type for QR code
# Select model: 1, 2 or micro.
self._send_2d_code_data(six.int2byte(65), cn, six.int2byte(48 + model) + six.int2byte(0))
# Set dot size.
self._send_2d_code_data(six.int2byte(67), cn, six.int2byte(size))
# Set error correction level: L, M, Q, or H
self._send_2d_code_data(six.int2byte(69), cn, six.int2byte(48 + ec))
# Send content & print
self._send_2d_code_data(six.int2byte(80), cn, content.encode('utf-8'), b'0')
self._send_2d_code_data(six.int2byte(81), cn, b'', b'0')
def _send_2d_code_data(self, fn, cn, data, m=b''):
""" Wrapper for GS ( k, to calculate and send correct data length.
:param fn: Function to use.
:param cn: Output code type. Affects available data.
:param data: Data to send.
:param m: Modifier/variant for function. Often '0' where used.
"""
if len(m) > 1 or len(cn) != 1 or len(fn) != 1:
raise ValueError("cn and fn must be one byte each.")
header = self._int_low_high(len(data) + len(m) + 2, 2)
self._raw(GS + b'(k' + header + cn + fn + m + data)
@staticmethod
def _int_low_high(inp_number, out_bytes):
""" Generate multiple bytes for a number: In lower and higher parts, or more parts as needed.
:param inp_number: Input number
:param out_bytes: The number of bytes to output (1 - 4).
"""
max_input = (256 << (out_bytes * 8) - 1)
if not 1 <= out_bytes <= 4:
raise ValueError("Can only output 1-4 byes")
if not 0 <= inp_number <= max_input:
raise ValueError("Number too large. Can only output up to {0} in {1} byes".format(max_input, out_bytes))
outp = b''
for _ in range(0, out_bytes):
outp += six.int2byte(inp_number % 256)
inp_number //= 256
return outp
[docs] def charcode(self, code):
""" Set Character Code Table
Sends the control sequence from :py:mod:`escpos.constants` to the printer
with :py:meth:`escpos.printer.'implementation'._raw()`.
:param code: Name of CharCode
:raises: :py:exc:`~escpos.exceptions.CharCodeError`
"""
# TODO improve this (rather unhandy code)
# TODO check the codepages
if code.upper() == "USA":
self._raw(CHARCODE_PC437)
self.codepage = 'cp437'
elif code.upper() == "JIS":
self._raw(CHARCODE_JIS)
self.codepage = 'cp932'
elif code.upper() == "MULTILINGUAL":
self._raw(CHARCODE_PC850)
self.codepage = 'cp850'
elif code.upper() == "PORTUGUESE":
self._raw(CHARCODE_PC860)
self.codepage = 'cp860'
elif code.upper() == "CA_FRENCH":
self._raw(CHARCODE_PC863)
self.codepage = 'cp863'
elif code.upper() == "NORDIC":
self._raw(CHARCODE_PC865)
self.codepage = 'cp865'
elif code.upper() == "WEST_EUROPE":
self._raw(CHARCODE_WEU)
self.codepage = 'latin_1'
elif code.upper() == "GREEK":
self._raw(CHARCODE_GREEK)
self.codepage = 'cp737'
elif code.upper() == "HEBREW":
self._raw(CHARCODE_HEBREW)
self.codepage = 'cp862'
# elif code.upper() == "LATVIAN": # this is not listed in the constants
# self._raw(CHARCODE_PC755)
# self.codepage = 'cp'
elif code.upper() == "WPC1252":
self._raw(CHARCODE_PC1252)
self.codepage = 'cp1252'
elif code.upper() == "CIRILLIC2":
self._raw(CHARCODE_PC866)
self.codepage = 'cp866'
elif code.upper() == "LATIN2":
self._raw(CHARCODE_PC852)
self.codepage = 'cp852'
elif code.upper() == "EURO":
self._raw(CHARCODE_PC858)
self.codepage = 'cp858'
elif code.upper() == "THAI42":
self._raw(CHARCODE_THAI42)
self.codepage = 'cp874'
elif code.upper() == "THAI11":
self._raw(CHARCODE_THAI11)
self.codepage = 'cp874'
elif code.upper() == "THAI13":
self._raw(CHARCODE_THAI13)
self.codepage = 'cp874'
elif code.upper() == "THAI14":
self._raw(CHARCODE_THAI14)
self.codepage = 'cp874'
elif code.upper() == "THAI16":
self._raw(CHARCODE_THAI16)
self.codepage = 'cp874'
elif code.upper() == "THAI17":
self._raw(CHARCODE_THAI17)
self.codepage = 'cp874'
elif code.upper() == "THAI18":
self._raw(CHARCODE_THAI18)
self.codepage = 'cp874'
else:
raise CharCodeError()
[docs] def barcode(self, code, bc, height=64, width=3, pos="BELOW", font="A", align_ct=True, function_type="A"):
""" Print Barcode
This method allows to print barcodes. The rendering of the barcode is done by the printer and therefore has to
be supported by the unit. Currently you have to check manually whether your barcode text is correct. Uncorrect
barcodes may lead to unexpected printer behaviour. There are two forms of the barcode function. Type A is
default but has fewer barcodes, while type B has some more to choose from.
.. todo:: Add a method to check barcode codes. Alternatively or as an addition write explanations about each
barcode-type. Research whether the check digits can be computed autmatically.
Use the parameters `height` and `width` for adjusting of the barcode size. Please take notice that the barcode
will not be printed if it is outside of the printable area. (Which should be impossible with this method, so
this information is probably more useful for debugging purposes.)
.. todo:: On TM-T88II width from 1 to 6 is accepted. Try to acquire command reference and correct the code.
.. todo:: Supplying pos does not have an effect for every barcode type. Check and document for which types this
is true.
If you do not want to center the barcode you can call the method with `align_ct=False`, which will disable
automatic centering. Please note that when you use center alignment, then the alignment of text will be changed
automatically to centered. You have to manually restore the alignment if necessary.
.. todo:: If further barcode-types are needed they could be rendered transparently as an image. (This could also
be of help if the printer does not support types that others do.)
:param code: alphanumeric data to be printed as bar code
:param bc: barcode format, possible values are for type A are:
* UPC-A
* UPC-E
* EAN13
* EAN8
* CODE39
* ITF
* NW7
Possible values for type B:
* All types from function type A
* CODE93
* CODE128
* GS1-128
* GS1 DataBar Omnidirectional
* GS1 DataBar Truncated
* GS1 DataBar Limited
* GS1 DataBar Expanded
If none is specified, the method raises :py:exc:`~escpos.exceptions.BarcodeTypeError`.
:param height: barcode height, has to be between 1 and 255
*default*: 64
:type height: int
:param width: barcode width, has to be between 2 and 6
*default*: 3
:type width: int
:param pos: where to place the text relative to the barcode, *default*: BELOW
* ABOVE
* BELOW
* BOTH
* OFF
:param font: select font (see ESC/POS-documentation, the device often has two fonts), *default*: A
* A
* B
:param align_ct: If this parameter is True the barcode will be centered. Otherwise no alignment command will be
issued.
:type align_ct: bool
:param function_type: Choose between ESCPOS function type A or B, depending on printer support and desired
barcode.
*default*: A
:raises: :py:exc:`~escpos.exceptions.BarcodeSizeError`,
:py:exc:`~escpos.exceptions.BarcodeTypeError`,
:py:exc:`~escpos.exceptions.BarcodeCodeError`
"""
# Align Bar Code()
if align_ct:
self._raw(TXT_ALIGN_CT)
# Height
if 1 <= height <= 255:
self._raw(BARCODE_HEIGHT + six.int2byte(height))
else:
raise BarcodeSizeError("height = {height}".format(height=height))
# Width
if 2 <= width <= 6:
self._raw(BARCODE_WIDTH + six.int2byte(width))
else:
raise BarcodeSizeError("width = {width}".format(width=width))
# Font
if font.upper() == "B":
self._raw(BARCODE_FONT_B)
else: # DEFAULT FONT: A
self._raw(BARCODE_FONT_A)
# Position
if pos.upper() == "OFF":
self._raw(BARCODE_TXT_OFF)
elif pos.upper() == "BOTH":
self._raw(BARCODE_TXT_BTH)
elif pos.upper() == "ABOVE":
self._raw(BARCODE_TXT_ABV)
else: # DEFAULT POSITION: BELOW
self._raw(BARCODE_TXT_BLW)
bc_types = BARCODE_TYPES[function_type.upper()]
if bc.upper() not in bc_types.keys():
# TODO: Raise a better error, or fix the message of this error type
raise BarcodeTypeError("Barcode type {bc} not valid for barcode function type {function_type}".format(
bc=bc,
function_type=function_type,
))
self._raw(bc_types[bc.upper()])
if function_type.upper() == "B":
self._raw(six.int2byte(len(code)))
# Print Code
if code:
self._raw(code.encode())
else:
raise BarcodeCodeError()
if function_type.upper() == "A":
self._raw(NUL)
[docs] def text(self, txt):
""" Print alpha-numeric text
The text has to be encoded in the currently selected codepage.
The input text has to be encoded in unicode.
:param txt: text to be printed
:raises: :py:exc:`~escpos.exceptions.TextError`
"""
if txt:
if self.codepage:
self._raw(txt.encode(self.codepage))
else:
self._raw(txt.encode())
else:
# TODO: why is it problematic to print an empty string?
raise TextError()
[docs] def block_text(self, txt, columns=None):
""" Text is printed wrapped to specified columns
Text has to be encoded in unicode.
:param txt: text to be printed
:param columns: amount of columns
:return: None
"""
col_count = self.columns if columns is None else columns
self.text(textwrap.fill(txt, col_count))
[docs] def set(self, align='left', font='a', text_type='normal', width=1, height=1, density=9, invert=False, smooth=False,
flip=False):
""" Set text properties by sending them to the printer
:param align: horizontal position for text, possible values are:
* CENTER
* LEFT
* RIGHT
*default*: LEFT
:param font: font type, possible values are A or B, *default*: A
:param text_type: text type, possible values are:
* B for bold
* U for underlined
* U2 for underlined, version 2
* BU for bold and underlined
* BU2 for bold and underlined, version 2
* NORMAL for normal text
*default*: NORMAL
:param width: text width multiplier, decimal range 1-8, *default*: 1
:param height: text height multiplier, decimal range 1-8, *default*: 1
:param density: print density, value from 0-8, if something else is supplied the density remains unchanged
:param invert: True enables white on black printing, *default*: False
:param smooth: True enables text smoothing. Effective on 4x4 size text and larger, *default*: False
:param flip: True enables upside-down printing, *default*: False
:type invert: bool
"""
# Width
if height == 2 and width == 2:
self._raw(TXT_NORMAL)
self._raw(TXT_4SQUARE)
elif height == 2 and width == 1:
self._raw(TXT_NORMAL)
self._raw(TXT_2HEIGHT)
elif width == 2 and height == 1:
self._raw(TXT_NORMAL)
self._raw(TXT_2WIDTH)
elif width == 1 and height == 1:
self._raw(TXT_NORMAL)
elif 1 <= width <= 8 and 1 <= height <= 8 and isinstance(width, int) and isinstance(height, int):
self._raw(TXT_SIZE + six.int2byte(TXT_WIDTH[width] + TXT_HEIGHT[height]))
else:
raise SetVariableError()
# Upside down
if flip:
self._raw(TXT_FLIP_ON)
else:
self._raw(TXT_FLIP_OFF)
# Smoothing
if smooth:
self._raw(TXT_SMOOTH_ON)
else:
self._raw(TXT_SMOOTH_OFF)
# Type
if text_type.upper() == "B":
self._raw(TXT_BOLD_ON)
self._raw(TXT_UNDERL_OFF)
elif text_type.upper() == "U":
self._raw(TXT_BOLD_OFF)
self._raw(TXT_UNDERL_ON)
elif text_type.upper() == "U2":
self._raw(TXT_BOLD_OFF)
self._raw(TXT_UNDERL2_ON)
elif text_type.upper() == "BU":
self._raw(TXT_BOLD_ON)
self._raw(TXT_UNDERL_ON)
elif text_type.upper() == "BU2":
self._raw(TXT_BOLD_ON)
self._raw(TXT_UNDERL2_ON)
elif text_type.upper() == "NORMAL":
self._raw(TXT_BOLD_OFF)
self._raw(TXT_UNDERL_OFF)
# Font
if font.upper() == "B":
self._raw(TXT_FONT_B)
else: # DEFAULT FONT: A
self._raw(TXT_FONT_A)
# Align
if align.upper() == "CENTER":
self._raw(TXT_ALIGN_CT)
elif align.upper() == "RIGHT":
self._raw(TXT_ALIGN_RT)
elif align.upper() == "LEFT":
self._raw(TXT_ALIGN_LT)
# Density
if density == 0:
self._raw(PD_N50)
elif density == 1:
self._raw(PD_N37)
elif density == 2:
self._raw(PD_N25)
elif density == 3:
self._raw(PD_N12)
elif density == 4:
self._raw(PD_0)
elif density == 5:
self._raw(PD_P12)
elif density == 6:
self._raw(PD_P25)
elif density == 7:
self._raw(PD_P37)
elif density == 8:
self._raw(PD_P50)
else: # DEFAULT: DOES NOTHING
pass
# Invert Printing
if invert:
self._raw(TXT_INVERT_ON)
else:
self._raw(TXT_INVERT_OFF)
[docs] def cut(self, mode=''):
""" Cut paper.
Without any arguments the paper will be cut completely. With 'mode=PART' a partial cut will
be attempted. Note however, that not all models can do a partial cut. See the documentation of
your printer for details.
.. todo:: Check this function on TM-T88II.
:param mode: set to 'PART' for a partial cut
"""
# Fix the size between last line and cut
# TODO: handle this with a line feed
self._raw(b"\n\n\n\n\n\n")
if mode.upper() == "PART":
self._raw(PAPER_PART_CUT)
else: # DEFAULT MODE: FULL CUT
self._raw(PAPER_FULL_CUT)
[docs] def cashdraw(self, pin):
""" Send pulse to kick the cash drawer
Kick cash drawer on pin 2 or pin 5 according to parameter.
:param pin: pin number, 2 or 5
:raises: :py:exc:`~escpos.exceptions.CashDrawerError`
"""
if pin == 2:
self._raw(CD_KICK_2)
elif pin == 5:
self._raw(CD_KICK_5)
else:
raise CashDrawerError()
[docs] def hw(self, hw):
""" Hardware operations
:param hw: hardware action, may be:
* INIT
* SELECT
* RESET
"""
if hw.upper() == "INIT":
self._raw(HW_INIT)
elif hw.upper() == "SELECT":
self._raw(HW_SELECT)
elif hw.upper() == "RESET":
self._raw(HW_RESET)
else: # DEFAULT: DOES NOTHING
pass
[docs] def control(self, ctl, pos=4):
""" Feed control sequences
:param ctl: string for the following control sequences:
* LF *for Line Feed*
* FF *for Form Feed*
* CR *for Carriage Return*
* HT *for Horizontal Tab*
* VT *for Vertical Tab*
:param pos: integer between 1 and 16, controls the horizontal tab position
:raises: :py:exc:`~escpos.exceptions.TabPosError`
"""
# Set tab positions
if not (1 <= pos <= 16):
raise TabPosError()
else:
self._raw(CTL_SET_HT + six.int2byte(pos))
# Set position
if ctl.upper() == "LF":
self._raw(CTL_LF)
elif ctl.upper() == "FF":
self._raw(CTL_FF)
elif ctl.upper() == "CR":
self._raw(CTL_CR)
elif ctl.upper() == "HT":
self._raw(CTL_HT)
elif ctl.upper() == "VT":
self._raw(CTL_VT)
[docs]class EscposIO(object):
"""ESC/POS Printer IO object
Allows the class to be used together with the `with`-statement. You have to define a printer instance
and assign it to the EsposIO-class.
This example explains the usage:
.. code-block:: Python
with EscposIO(printer.Serial('/dev/ttyUSB0')) as p:
p.set(font='a', height=2, align='center', text_type='bold')
p.printer.set(align='left')
p.printer.image('logo.gif')
p.writelines('Big line\\n', font='b')
p.writelines('Привет')
p.writelines('BIG TEXT', width=2)
After the `with`-statement the printer automatically cuts the paper if `autocut` is `True`.
"""
def __init__(self, printer, autocut=True, autoclose=True, **kwargs):
"""
:param printer: An EscPos-printer object
:type printer: escpos.Escpos
:param autocut: If True, paper is automatically cut after the `with`-statement *default*: True
:param kwargs: These arguments will be passed to :py:meth:`escpos.Escpos.set()`
"""
self.printer = printer
self.params = kwargs
self.autocut = autocut
self.autoclose = autoclose
[docs] def set(self, **kwargs):
""" Set the printer-parameters
Controls which parameters will be passed to :py:meth:`Escpos.set() <escpos.escpos.Escpos.set()>`.
For more information on the parameters see the :py:meth:`set() <escpos.escpos.Escpos.set()>`-methods
documentation. These parameters can also be passed with this class' constructor or the
:py:meth:`~escpos.escpos.EscposIO.writelines()`-method.
:param kwargs: keyword-parameters that will be passed to :py:meth:`Escpos.set() <escpos.escpos.Escpos.set()>`
"""
self.params.update(kwargs)
[docs] def writelines(self, text, **kwargs):
params = dict(self.params)
params.update(kwargs)
if isinstance(text, six.text_type):
lines = text.split('\n')
elif isinstance(text, list) or isinstance(text, tuple):
lines = text
else:
lines = ["{0}".format(text), ]
# TODO check unicode handling
# TODO flush? or on print? (this should prob rather be handled by the _raw-method)
for line in lines:
self.printer.set(**params)
if isinstance(text, six.text_type):
self.printer.text(u"{0}\n".format(line))
else:
self.printer.text("{0}\n".format(line))
[docs] def close(self):
""" called upon closing the `with`-statement
"""
self.printer.close()
def __enter__(self, **kwargs):
return self
def __exit__(self, type, value, traceback):
"""
If :py:attr:`autocut <escpos.escpos.EscposIO.autocut>` is `True` (set by this class' constructor),
then :py:meth:`printer.cut() <escpos.escpos.Escpos.cut()>` will be called here.
"""
if not (type is not None and issubclass(type, Exception)):
if self.autocut:
self.printer.cut()
if self.autoclose:
self.close()