# -*- coding: utf-8 -*- import time import copy import io import base64 import math import md5 import re import traceback import xml.etree.ElementTree as ET import xml.dom.minidom as minidom from PIL import Image try: import jcconv except ImportError: jcconv = None try: import qrcode except ImportError: qrcode = None from constants import * from exceptions import * def utfstr(stuff): """ converts stuff to string and does without failing if stuff is a utf8 string """ if isinstance(stuff,basestring): return stuff else: return str(stuff) class StyleStack: """ The stylestack is used by the xml receipt serializer to compute the active styles along the xml document. Styles are just xml attributes, there is no css mechanism. But the style applied by the attributes are inherited by deeper nodes. """ def __init__(self): self.stack = [] self.defaults = { # default style values 'align': 'left', 'underline': 'off', 'bold': 'off', 'size': 'normal', 'font' : 'a', 'width': 48, 'indent': 0, 'tabwidth': 2, 'bullet': ' - ', 'line-ratio':0.5, 'color': 'black', 'value-decimals': 2, 'value-symbol': '', 'value-symbol-position': 'after', 'value-autoint': 'off', 'value-decimals-separator': '.', 'value-thousands-separator': ',', 'value-width': 0, } self.types = { # attribute types, default is string and can be ommitted 'width': 'int', 'indent': 'int', 'tabwidth': 'int', 'line-ratio': 'float', 'value-decimals': 'int', 'value-width': 'int', } self.cmds = { # translation from styles to escpos commands # some style do not correspond to escpos command are used by # the serializer instead 'align': { 'left': TXT_ALIGN_LT, 'right': TXT_ALIGN_RT, 'center': TXT_ALIGN_CT, '_order': 1, }, 'underline': { 'off': TXT_UNDERL_OFF, 'on': TXT_UNDERL_ON, 'double': TXT_UNDERL2_ON, # must be issued after 'size' command # because ESC ! resets ESC - '_order': 10, }, 'bold': { 'off': TXT_BOLD_OFF, 'on': TXT_BOLD_ON, # must be issued after 'size' command # because ESC ! resets ESC - '_order': 10, }, 'font': { 'a': TXT_FONT_A, 'b': TXT_FONT_B, # must be issued after 'size' command # because ESC ! resets ESC - '_order': 10, }, 'size': { 'normal': TXT_NORMAL, 'double-height': TXT_2HEIGHT, 'double-width': TXT_2WIDTH, 'double': TXT_DOUBLE, '_order': 1, }, 'color': { 'black': TXT_COLOR_BLACK, 'red': TXT_COLOR_RED, '_order': 1, }, } self.push(self.defaults) def get(self,style): """ what's the value of a style at the current stack level""" level = len(self.stack) -1 while level >= 0: if style in self.stack[level]: return self.stack[level][style] else: level = level - 1 return None def enforce_type(self, attr, val): """converts a value to the attribute's type""" if not attr in self.types: return utfstr(val) elif self.types[attr] == 'int': return int(float(val)) elif self.types[attr] == 'float': return float(val) else: return utfstr(val) def push(self, style={}): """push a new level on the stack with a style dictionnary containing style:value pairs""" _style = {} for attr in style: if attr in self.cmds and not style[attr] in self.cmds[attr]: print 'WARNING: ESC/POS PRINTING: ignoring invalid value: '+utfstr(style[attr])+' for style: '+utfstr(attr) else: _style[attr] = self.enforce_type(attr, style[attr]) self.stack.append(_style) def set(self, style={}): """overrides style values at the current stack level""" _style = {} for attr in style: if attr in self.cmds and not style[attr] in self.cmds[attr]: print 'WARNING: ESC/POS PRINTING: ignoring invalid value: '+utfstr(style[attr])+' for style: '+utfstr(attr) else: self.stack[-1][attr] = self.enforce_type(attr, style[attr]) def pop(self): """ pop a style stack level """ if len(self.stack) > 1 : self.stack = self.stack[:-1] def to_escpos(self): """ converts the current style to an escpos command string """ cmd = '' ordered_cmds = self.cmds.keys() ordered_cmds.sort(lambda x,y: cmp(self.cmds[x]['_order'], self.cmds[y]['_order'])) for style in ordered_cmds: cmd += self.cmds[style][self.get(style)] return cmd class XmlSerializer: """ Converts the xml inline / block tree structure to a string, keeping track of newlines and spacings. The string is outputted asap to the provided escpos driver. """ def __init__(self,escpos): self.escpos = escpos self.stack = ['block'] self.dirty = False def start_inline(self,stylestack=None): """ starts an inline entity with an optional style definition """ self.stack.append('inline') if self.dirty: self.escpos._raw(' ') if stylestack: self.style(stylestack) def start_block(self,stylestack=None): """ starts a block entity with an optional style definition """ if self.dirty: self.escpos._raw('\n') self.dirty = False self.stack.append('block') if stylestack: self.style(stylestack) def end_entity(self): """ ends the entity definition. (but does not cancel the active style!) """ if self.stack[-1] == 'block' and self.dirty: self.escpos._raw('\n') self.dirty = False if len(self.stack) > 1: self.stack = self.stack[:-1] def pre(self,text): """ puts a string of text in the entity keeping the whitespace intact """ if text: self.escpos.text(text) self.dirty = True def text(self,text): """ puts text in the entity. Whitespace and newlines are stripped to single spaces. """ if text: text = utfstr(text) text = text.strip() text = re.sub('\s+',' ',text) if text: self.dirty = True self.escpos.text(text) def linebreak(self): """ inserts a linebreak in the entity """ self.dirty = False self.escpos._raw('\n') def style(self,stylestack): """ apply a style to the entity (only applies to content added after the definition) """ self.raw(stylestack.to_escpos()) def raw(self,raw): """ puts raw text or escpos command in the entity without affecting the state of the serializer """ self.escpos._raw(raw) class XmlLineSerializer: """ This is used to convert a xml tree into a single line, with a left and a right part. The content is not output to escpos directly, and is intended to be fedback to the XmlSerializer as the content of a block entity. """ def __init__(self, indent=0, tabwidth=2, width=48, ratio=0.5): self.tabwidth = tabwidth self.indent = indent self.width = max(0, width - int(tabwidth*indent)) self.lwidth = int(self.width*ratio) self.rwidth = max(0, self.width - self.lwidth) self.clwidth = 0 self.crwidth = 0 self.lbuffer = '' self.rbuffer = '' self.left = True def _txt(self,txt): if self.left: if self.clwidth < self.lwidth: txt = txt[:max(0, self.lwidth - self.clwidth)] self.lbuffer += txt self.clwidth += len(txt) else: if self.crwidth < self.rwidth: txt = txt[:max(0, self.rwidth - self.crwidth)] self.rbuffer += txt self.crwidth += len(txt) def start_inline(self,stylestack=None): if (self.left and self.clwidth) or (not self.left and self.crwidth): self._txt(' ') def start_block(self,stylestack=None): self.start_inline(stylestack) def end_entity(self): pass def pre(self,text): if text: self._txt(text) def text(self,text): if text: text = utfstr(text) text = text.strip() text = re.sub('\s+',' ',text) if text: self._txt(text) def linebreak(self): pass def style(self,stylestack): pass def raw(self,raw): pass def start_right(self): self.left = False def get_line(self): return ' ' * self.indent * self.tabwidth + self.lbuffer + ' ' * (self.width - self.clwidth - self.crwidth) + self.rbuffer class Escpos: """ ESC/POS Printer object """ device = None encoding = None img_cache = {} def _check_image_size(self, size): """ Check and fix the size of the image to 32 bits """ if size % 32 == 0: return (0, 0) else: image_border = 32 - (size % 32) if (image_border % 2) == 0: return (image_border / 2, image_border / 2) else: return (image_border / 2, (image_border / 2) + 1) def _print_image(self, line, size): """ Print formatted image """ i = 0 cont = 0 buffer = "" self._raw(S_RASTER_N) buffer = "%02X%02X%02X%02X" % (((size[0]/size[1])/8), 0, size[1], 0) self._raw(buffer.decode('hex')) buffer = "" while i < len(line): hex_string = int(line[i:i+8],2) buffer += "%02X" % hex_string i += 8 cont += 1 if cont % 4 == 0: self._raw(buffer.decode("hex")) buffer = "" cont = 0 def _raw_print_image(self, line, size, output=None ): """ Print formatted image """ i = 0 cont = 0 buffer = "" raw = "" def __raw(string): if output: output(string) else: self._raw(string) raw += S_RASTER_N buffer = "%02X%02X%02X%02X" % (((size[0]/size[1])/8), 0, size[1], 0) raw += buffer.decode('hex') buffer = "" while i < len(line): hex_string = int(line[i:i+8],2) buffer += "%02X" % hex_string i += 8 cont += 1 if cont % 4 == 0: raw += buffer.decode("hex") buffer = "" cont = 0 return raw def _convert_image(self, im): """ Parse image and prepare it to a printable format """ pixels = [] pix_line = "" im_left = "" im_right = "" switch = 0 img_size = [ 0, 0 ] if im.size[0] > 512: print "WARNING: Image is wider than 512 and could be truncated at print time " if im.size[1] > 255: raise ImageSizeError() im_border = self._check_image_size(im.size[0]) for i in range(im_border[0]): im_left += "0" for i in range(im_border[1]): im_right += "0" for y in range(im.size[1]): img_size[1] += 1 pix_line += im_left img_size[0] += im_border[0] for x in range(im.size[0]): img_size[0] += 1 RGB = im.getpixel((x, y)) im_color = (RGB[0] + RGB[1] + RGB[2]) im_pattern = "1X0" pattern_len = len(im_pattern) switch = (switch - 1 ) * (-1) for x in range(pattern_len): if im_color <= (255 * 3 / pattern_len * (x+1)): if im_pattern[x] == "X": pix_line += "%d" % switch else: pix_line += im_pattern[x] break elif im_color > (255 * 3 / pattern_len * pattern_len) and im_color <= (255 * 3): pix_line += im_pattern[-1] break pix_line += im_right img_size[0] += im_border[1] return (pix_line, img_size) def image(self,path_img): """ Open image file """ im_open = Image.open(path_img) im = im_open.convert("RGB") # Convert the RGB image in printable image pix_line, img_size = self._convert_image(im) self._print_image(pix_line, img_size) def print_base64_image(self,img): print 'print_b64_img' id = md5.new(img).digest() if id not in self.img_cache: print 'not in cache' img = img[img.find(',')+1:] f = io.BytesIO('img') f.write(base64.decodestring(img)) f.seek(0) img_rgba = Image.open(f) img = Image.new('RGB', img_rgba.size, (255,255,255)) channels = img_rgba.split() if len(channels) > 3: # use alpha channel as mask img.paste(img_rgba, mask=channels[3]) else: img.paste(img_rgba) print 'convert image' pix_line, img_size = self._convert_image(img) print 'print image' buffer = self._raw_print_image(pix_line, img_size) self.img_cache[id] = buffer print 'raw image' self._raw(self.img_cache[id]) def qr(self,text): """ Print QR Code for the provided string """ qr_code = qrcode.QRCode(version=4, box_size=4, border=1) qr_code.add_data(text) 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._convert_image(im) def barcode(self, code, bc, width=255, height=2, pos='below', font='a'): """ Print Barcode """ # Align Bar Code() self._raw(TXT_ALIGN_CT) # Height if height >=2 or height <=6: self._raw(BARCODE_HEIGHT) else: raise BarcodeSizeError() # Width if width >= 1 or width <=255: self._raw(BARCODE_WIDTH) else: raise BarcodeSizeError() # 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) # Type if bc.upper() == "UPC-A": self._raw(BARCODE_UPC_A) elif bc.upper() == "UPC-E": self._raw(BARCODE_UPC_E) elif bc.upper() == "EAN13": self._raw(BARCODE_EAN13) elif bc.upper() == "EAN8": self._raw(BARCODE_EAN8) elif bc.upper() == "CODE39": self._raw(BARCODE_CODE39) elif bc.upper() == "ITF": self._raw(BARCODE_ITF) elif bc.upper() == "NW7": self._raw(BARCODE_NW7) else: raise BarcodeTypeError() # Print Code if code: self._raw(code) else: raise exception.BarcodeCodeError() def receipt(self,xml): """ Prints an xml based receipt definition """ def strclean(string): if not string: string = '' string = string.strip() string = re.sub('\s+',' ',string) return string def format_value(value, decimals=3, width=0, decimals_separator='.', thousands_separator=',', autoint=False, symbol='', position='after'): decimals = max(0,int(decimals)) width = max(0,int(width)) value = float(value) if autoint and math.floor(value) == value: decimals = 0 if width == 0: width = '' if thousands_separator: formatstr = "{:"+str(width)+",."+str(decimals)+"f}" else: formatstr = "{:"+str(width)+"."+str(decimals)+"f}" ret = formatstr.format(value) ret = ret.replace(',','COMMA') ret = ret.replace('.','DOT') ret = ret.replace('COMMA',thousands_separator) ret = ret.replace('DOT',decimals_separator) if symbol: if position == 'after': ret = ret + symbol else: ret = symbol + ret return ret def print_elem(stylestack, serializer, elem, indent=0): elem_styles = { 'h1': {'bold': 'on', 'size':'double'}, 'h2': {'size':'double'}, 'h3': {'bold': 'on', 'size':'double-height'}, 'h4': {'size': 'double-height'}, 'h5': {'bold': 'on'}, 'em': {'font': 'b'}, 'b': {'bold': 'on'}, } stylestack.push() if elem.tag in elem_styles: stylestack.set(elem_styles[elem.tag]) stylestack.set(elem.attrib) if elem.tag in ('p','div','section','article','receipt','header','footer','li','h1','h2','h3','h4','h5'): serializer.start_block(stylestack) serializer.text(elem.text) for child in elem: print_elem(stylestack,serializer,child) serializer.start_inline(stylestack) serializer.text(child.tail) serializer.end_entity() serializer.end_entity() elif elem.tag in ('span','em','b','left','right'): serializer.start_inline(stylestack) serializer.text(elem.text) for child in elem: print_elem(stylestack,serializer,child) serializer.start_inline(stylestack) serializer.text(child.tail) serializer.end_entity() serializer.end_entity() elif elem.tag == 'value': serializer.start_inline(stylestack) serializer.pre(format_value( elem.text, decimals=stylestack.get('value-decimals'), width=stylestack.get('value-width'), decimals_separator=stylestack.get('value-decimals-separator'), thousands_separator=stylestack.get('value-thousands-separator'), autoint=(stylestack.get('value-autoint') == 'on'), symbol=stylestack.get('value-symbol'), position=stylestack.get('value-symbol-position') )) serializer.end_entity() elif elem.tag == 'line': width = stylestack.get('width') if stylestack.get('size') in ('double', 'double-width'): width = width / 2 lineserializer = XmlLineSerializer(stylestack.get('indent')+indent,stylestack.get('tabwidth'),width,stylestack.get('line-ratio')) serializer.start_block(stylestack) for child in elem: if child.tag == 'left': print_elem(stylestack,lineserializer,child,indent=indent) elif child.tag == 'right': lineserializer.start_right() print_elem(stylestack,lineserializer,child,indent=indent) serializer.pre(lineserializer.get_line()) serializer.end_entity() elif elem.tag == 'ul': serializer.start_block(stylestack) bullet = stylestack.get('bullet') for child in elem: if child.tag == 'li': serializer.style(stylestack) serializer.raw(' ' * indent * stylestack.get('tabwidth') + bullet) print_elem(stylestack,serializer,child,indent=indent+1) serializer.end_entity() elif elem.tag == 'ol': cwidth = len(str(len(elem))) + 2 i = 1 serializer.start_block(stylestack) for child in elem: if child.tag == 'li': serializer.style(stylestack) serializer.raw(' ' * indent * stylestack.get('tabwidth') + ' ' + (str(i)+')').ljust(cwidth)) i = i + 1 print_elem(stylestack,serializer,child,indent=indent+1) serializer.end_entity() elif elem.tag == 'pre': serializer.start_block(stylestack) serializer.pre(elem.text) serializer.end_entity() elif elem.tag == 'hr': width = stylestack.get('width') if stylestack.get('size') in ('double', 'double-width'): width = width / 2 serializer.start_block(stylestack) serializer.text('-'*width) serializer.end_entity() elif elem.tag == 'br': serializer.linebreak() elif elem.tag == 'img': if 'src' in elem.attrib and 'data:' in elem.attrib['src']: self.print_base64_image(elem.attrib['src']) elif elem.tag == 'barcode' and 'encoding' in elem.attrib: serializer.start_block(stylestack) self.barcode(strclean(elem.text),elem.attrib['encoding']) serializer.end_entity() elif elem.tag == 'cut': self.cut() elif elem.tag == 'partialcut': self.cut(mode='part') elif elem.tag == 'cashdraw': self.cashdraw(2) self.cashdraw(5) stylestack.pop() try: stylestack = StyleStack() serializer = XmlSerializer(self) root = ET.fromstring(xml.encode('utf-8')) self._raw(stylestack.to_escpos()) print_elem(stylestack,serializer,root) if 'open-cashdrawer' in root.attrib and root.attrib['open-cashdrawer'] == 'true': self.cashdraw(2) self.cashdraw(5) if not 'cut' in root.attrib or root.attrib['cut'] == 'true' : self.cut() except Exception as e: errmsg = str(e)+'\n'+'-'*48+'\n'+traceback.format_exc() + '-'*48+'\n' self.text(errmsg) self.cut() raise e def text(self,txt): """ Print Utf8 encoded alpha-numeric text """ if not txt: return try: txt = txt.decode('utf-8') except: try: txt = txt.decode('utf-16') except: pass self.extra_chars = 0 def encode_char(char): """ Encodes a single utf-8 character into a sequence of esc-pos code page change instructions and character declarations """ char_utf8 = char.encode('utf-8') encoded = '' encoding = self.encoding # we reuse the last encoding to prevent code page switches at every character encodings = { # TODO use ordering to prevent useless switches # TODO Support other encodings not natively supported by python ( Thai, Khazakh, Kanjis ) 'cp437': TXT_ENC_PC437, 'cp850': TXT_ENC_PC850, 'cp852': TXT_ENC_PC852, 'cp857': TXT_ENC_PC857, 'cp858': TXT_ENC_PC858, 'cp860': TXT_ENC_PC860, 'cp863': TXT_ENC_PC863, 'cp865': TXT_ENC_PC865, 'cp866': TXT_ENC_PC866, 'cp862': TXT_ENC_PC862, 'cp720': TXT_ENC_PC720, 'cp936': TXT_ENC_PC936, 'iso8859_2': TXT_ENC_8859_2, 'iso8859_7': TXT_ENC_8859_7, 'iso8859_9': TXT_ENC_8859_9, 'cp1254' : TXT_ENC_WPC1254, 'cp1255' : TXT_ENC_WPC1255, 'cp1256' : TXT_ENC_WPC1256, 'cp1257' : TXT_ENC_WPC1257, 'cp1258' : TXT_ENC_WPC1258, 'katakana' : TXT_ENC_KATAKANA, } remaining = copy.copy(encodings) if not encoding : encoding = 'cp437' while True: # Trying all encoding until one succeeds try: if encoding == 'katakana': # Japanese characters if jcconv: # try to convert japanese text to a half-katakanas kata = jcconv.kata2half(jcconv.hira2kata(char_utf8)) if kata != char_utf8: self.extra_chars += len(kata.decode('utf-8')) - 1 # the conversion may result in multiple characters return encode_str(kata.decode('utf-8')) else: kata = char_utf8 if kata in TXT_ENC_KATAKANA_MAP: encoded = TXT_ENC_KATAKANA_MAP[kata] break else: raise ValueError() else: encoded = char.encode(encoding) break except ValueError: #the encoding failed, select another one and retry if encoding in remaining: del remaining[encoding] if len(remaining) >= 1: encoding = remaining.items()[0][0] else: encoding = 'cp437' encoded = '\xb1' # could not encode, output error character break; if encoding != self.encoding: # if the encoding changed, remember it and prefix the character with # the esc-pos encoding change sequence self.encoding = encoding encoded = encodings[encoding] + encoded return encoded def encode_str(txt): buffer = '' for c in txt: buffer += encode_char(c) return buffer txt = encode_str(txt) # if the utf-8 -> codepage conversion inserted extra characters, # remove double spaces to try to restore the original string length # and prevent printing alignment issues while self.extra_chars > 0: dspace = txt.find(' ') if dspace > 0: txt = txt[:dspace] + txt[dspace+1:] self.extra_chars -= 1 else: break self._raw(txt) def set(self, align='left', font='a', type='normal', width=1, height=1): """ Set text properties """ # 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) # Font if font.upper() == "B": self._raw(TXT_FONT_B) else: # DEFAULT FONT: A self._raw(TXT_FONT_A) # Type if type.upper() == "B": self._raw(TXT_BOLD_ON) self._raw(TXT_UNDERL_OFF) elif type.upper() == "U": self._raw(TXT_BOLD_OFF) self._raw(TXT_UNDERL_ON) elif type.upper() == "U2": self._raw(TXT_BOLD_OFF) self._raw(TXT_UNDERL2_ON) elif type.upper() == "BU": self._raw(TXT_BOLD_ON) self._raw(TXT_UNDERL_ON) elif type.upper() == "BU2": self._raw(TXT_BOLD_ON) self._raw(TXT_UNDERL2_ON) elif type.upper == "NORMAL": self._raw(TXT_BOLD_OFF) self._raw(TXT_UNDERL_OFF) # Width if width == 2 and height != 2: self._raw(TXT_NORMAL) self._raw(TXT_2WIDTH) elif height == 2 and width != 2: self._raw(TXT_NORMAL) self._raw(TXT_2HEIGHT) elif height == 2 and width == 2: self._raw(TXT_2WIDTH) self._raw(TXT_2HEIGHT) else: # DEFAULT SIZE: NORMAL self._raw(TXT_NORMAL) def cut(self, mode=''): """ Cut paper """ # Fix the size between last line and cut # TODO: handle this with a line feed self._raw("\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) def cashdraw(self, pin): """ Send pulse to kick the cash drawer """ if pin == 2: self._raw(CD_KICK_2) elif pin == 5: self._raw(CD_KICK_5) else: raise CashDrawerError() def hw(self, hw): """ Hardware operations """ 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 def control(self, ctl): """ Feed control sequences """ 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)