def write_image_surface(doc, printer, resolution=96):
dppx = resolution / 96
# This duplicates the hinting logic in Page.paint. There is a
# dependency cycle otherwise:
# this → hinting logic → context → surface → this
# But since we do no transform here, cairo_context.user_to_device and
# friends are identity functions.
widths = [int(math.ceil(p.width * dppx)) for p in doc.pages]
heights = [
int(math.ceil(p._page_box.children[0].height * dppx))
for p in doc.pages
]
max_width = max(widths)
printer._raw(escpos.constants.ESC + b"3\x16")
for page, width, height in zip(doc.pages, widths, heights):
surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, max_width, height)
context = cairo.Context(surface)
pos_x = (max_width - width) / 2
page.paint(context, pos_x, 0, scale=dppx, clip=True)
target = io.BytesIO()
surface.write_to_png(target)
target.seek(0)
im = Image.open(target)
im.load()
im = convert_image(im)
print_image(im, printer)
printer._raw(escpos.constants.ESC + b"2")
def on_message(client, userdata: Context, msg: mqtt.MQTTMessage):
try:
payload = json.loads(msg.payload)
except json.decoder.JSONDecodeError as e:
print(f"JSON decode error {e}", flush=True)
return
subject = payload.get("subject")
if subject is None:
subject = "None"
message = payload.get("message")
if message is None:
return
attachments = payload.get("attachments")
if attachments is None:
attachments = {}
sender = payload.get("from")
formatted_time = time.strftime("%Y-%m-%dT%H:%M:%S")
printer = userdata.printer
print(f"New email from {sender}, subject: {subject}", flush=True)
print(message, flush=True)
# Print header
parse_html(
printer,
TEMPLATE.render(subject=subject, time=formatted_time, sender=sender),
{})
# Print message
parse_html(printer, message, attachments)
printer._raw(b"\n" * 3)
print("Done!", flush=True)
def print_image(im: Image.Image, printer: escpos.escpos.Escpos):
outp = []
header = escpos.constants.ESC + b"*\x21" + struct.pack("<H", im.width)
im = im.transpose(Image.ROTATE_270).transpose(Image.FLIP_LEFT_RIGHT)
line_height = 24
width_pixels, height_pixels = im.size
top = 0
left = 0
while left < width_pixels:
box = (left, top, left + line_height, top + height_pixels)
im_slice = im.transform((line_height, height_pixels), Image.EXTENT,
box)
im_bytes = im_slice.tobytes()
outp.append(header + im_bytes + b"\n")
left += line_height
printer._raw(b''.join(outp))
def print_codepage(printer, codepage):
printer.charcode(codepage)
# Table header
printer.set(text_type='B')
printer._raw(" %s\n" % " ".join(map(lambda s: hex(s)[2:], range(0, 16))))
printer.set()
# The table
for x in range(0, 16):
# First column
printer.set(text_type='B')
printer._raw("%s " % hex(x)[2:])
printer.set()
for y in range(0, 16):
byte = six.int2byte(x * 16 + y)
if byte in (ESC, CTL_LF, CTL_FF, CTL_CR, CTL_HT, CTL_VT):
byte = ' '
printer._raw(byte)
printer._raw(" ")
printer._raw('\n')
def print_codepage(printer, codepage):
if codepage.isdigit():
codepage = int(codepage)
printer._raw(CODEPAGE_CHANGE + six.int2byte(codepage))
printer._raw("after")
else:
printer.charcode(codepage)
sep = ""
# Table header
printer.set(text_type='B')
printer._raw(" {}\n".format(
sep.join(map(lambda s: hex(s)[2:], range(0, 16)))))
printer.set()
# The table
for x in range(0, 16):
# First column
printer.set(text_type='B')
printer._raw("{} ".format(hex(x)[2:]))
printer.set()
for y in range(0, 16):
byte = six.int2byte(x * 16 + y)
if byte in (ESC, CTL_LF, CTL_FF, CTL_CR, CTL_HT, CTL_VT):
byte = ' '
printer._raw(byte)
printer._raw(sep)
printer._raw('\n')
def print_codepage(printer, codepage):
if codepage.isdigit():
codepage = int(codepage)
printer._raw(CODEPAGE_CHANGE + six.int2byte(codepage))
printer._raw("after")
else:
printer.charcode(codepage)
sep = ""
# Table header
printer.set(text_type='B')
printer._raw(" {}\n".format(sep.join(map(lambda s: hex(s)[2:], range(0, 16)))))
printer.set()
# The table
for x in range(0, 16):
# First column
printer.set(text_type='B')
printer._raw("{} ".format(hex(x)[2:]))
printer.set()
for y in range(0, 16):
byte = six.int2byte(x * 16 + y)
if byte in (ESC, CTL_LF, CTL_FF, CTL_CR, CTL_HT, CTL_VT):
byte = ' '
printer._raw(byte)
printer._raw(sep)
printer._raw('\n')
# Print header
parse_html(
printer,
TEMPLATE.render(subject=subject, time=formatted_time, sender=sender),
{})
# Print message
parse_html(printer, message, attachments)
printer._raw(b"\n" * 3)
print("Done!", flush=True)
if __name__ == "__main__":
printer = escpos.printer.Usb(0x0416, 0x5011)
#printer = escpos.printer.Dummy()
printer._raw(escpos.constants.ESC + b"@")
context = Context(printer)
client = mqtt.Client(userdata=context)
client.on_connect = on_connect
client.message_callback_add("printer/print", on_message)
client.connect(os.getenv("MQTT_SERVER", "172.30.2.10"), 1883, 60)
while True:
try:
client.loop()
except (KeyboardInterrupt, SystemExit):
print("Bye!")
break