[SOLVED] Print PDF from web without saving to filesystem first

Print PDF from web without saving to filesystem first

In Python3.4 I am using the following code to print a PDF from a website using the requests library:

with open(temp_pdf_file, 'wb') as handle:
   response = requests.get(html.unescape(message['body']), stream=True)
   for block in response.iter_content(1024):
       handle.write(block)
cmd = '/usr/bin/lpr -P {} {}'.format(self.printer_name,temp_pdf_file)
print(cmd)
proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)
stdout, stderr = proc.communicate()
exit_code = proc.wait()

Is there a way to skip the temporary file save and stream directly the printer directly?

Solution

You can have the subprocess read its input from stdin and write to the stdin "file" directly.

import requests
from subprocess import Popen, PIPE

message = ...

cmd = '/usr/bin/lpr -P {}'.format(self.printer_name)
proc = Popen(cmd, stdin=PIPE, stdout=PIPE, stderr=PIPE, shell=True)
response = requests.get(html.unescape(message['body']), stream=True)
for block in response.iter_content(1024):
    proc.stdin.write(block)
stdout, stderr = proc.communicate()
exit_code = proc.wait()
print exit_code