pbs.convert raise an error

[ifduyue]

here is the command:

import pbs
pbs.convert("-crop +0+67", "some.jpg", "crop.jpg")

raises an error:

Traceback (most recent call last):
  File "test.py", line 5, in <module>
    pbs.convert("-crop +0+67", "some.jpg", "crop.jpg")
  File "/usr/lib/python2.7/site-packages/pbs.py", line 436, in __call__
    return RunningCommand(command_ran, process, call_args, actual_stdin)
  File "/usr/lib/python2.7/site-packages/pbs.py", line 142, in __init__
    self._handle_exit_code(self.process.wait())
  File "/usr/lib/python2.7/site-packages/pbs.py", line 207, in _handle_exit_code
    raise get_rc_exc(rc)(self.command_ran, self._stdout, self._stderr)
pbs.ErrorReturnCode_1: 

Ran: '/usr/bin/convert -crop +0+67 some.jpg crop.jpg'

STDOUT:



STDERR:

  convert: unrecognized option `-crop +0+67' @ error/convert.c/ConvertImageCommand/10

I found that subprocess.Popen(["/usr/bin/convert", "-crop", "+0+67", "some.jpg", "crop.jpg"]) is OK,
but subprocess.Popen(["/usr/bin/convert", "-crop +0+67", "some.jpg", "crop.jpg"]) is NOT.

Maybe this is not a bug, maybe it's subprocess's bug.
However, can psb take this situation into account and work around?

Thanks.

Best regards,
Du Yue

[ifduyue]

convert is a command tool ImageMagick provides

[amoffat]

Hi Du, unfortunately this is a problem with how pbs and shlex split up arguments. There will be a workaround in v1.0 if I can find it, but in the meantime, you can do this:

pbs.convert("-crop", "+0+67", "some.jpg", "crop.jpg")

[amoffat]

Just an update, there will be no workaround in v1.0. It seems that the best way to handle passing arguments to commands is to split them up with the understanding that 1 argument to the pbs command should correspond to 1 argument being passed to the subprocess. I've updated the readme to reflect this.

So in other words, this:

pbs.convert("-crop +0+67", "some.jpg", "crop.jpg")

should always be this:

pbs.convert("-crop", "+0+67", "some.jpg", "crop.jpg")

Because "-crop" and "+0+67" are separate arguments to the "convert" binary, and using shlex.split() to split up arguments automagically is broken and full of problems.

[ifduyue]

pbs.convert("-crop", "+0+67", "some.jpg", "crop.jpg") works.

thanks, amoffat.