Subprocess call python script not producing Jasper Report but cmd execution does

Question

When I run this at command line it generates my Jasper report correctly:

jasperstarter pr "C:\users\ant\jaspersoftworkspace\myreports\carereport.jrxml" -f pdf -t postgres -H localhost -n template_postgis_20 -u postgres -p postgres -P SiteID=123

However, if I then try to run it through python with the following code the report doesn't get created. Am I messing up the syntax somewhere?

import subprocess
from subprocess import call

subprocess.call(["cmd","/C","jasperstarter","pr","""C:\users\ant\jaspersoftworkspace\myreports\carereport.jrxml""","-f","pdf",
"-t","postgres","-H","localhost","-n","template_postgis_20","-u","postgres","-p","postgres",
"-P","SiteID=123"], shell=True)

EDIT:

Following the comments, I tried running this at cmd after typing python to bring up >>>:

jasperstarter pr "C:\users\ant\jaspersoftworkspace\myreports\carereport.jrxml" -f pdf -t postgres -H localhost -n template_postgis_20 -u postgres -p postgres -P SiteID=123

This time I got a syntax error at -u. I then tried reordering the parameters and the syntax error then occurred at the same character number, rather than at the -u. So is there a maximum line length when entering commands in python at cmd?

Answer 1

\\a is a escape sequence that is same to \\x07 (BEL). You should escape \\ or use raw string literal to make \\a represent \\a literally.

>>> '\a' # not escaped
'\x07'
>>> '\\a' # escaped
'\\a'
>>> r'\a' # raw string literal
'\\a'

So, replace following:

"""C:\users\ant\jaspersoftworkspace\myreports\carereport.jrxml"""

with

"""C:\\users\\ant\\jaspersoftworkspace\\myreports\\carereport.jrxml"""

or

r"""C:\users\ant\jaspersoftworkspace\myreports\carereport.jrxml"""

UPDATE

Try following:

subprocess.call(r'jasperstarter pr "C:\users\ant\jaspersoftworkspace\myreports\carereport.jrxml" -f pdf -t postgres -H localhost -n template_postgis_20 -u postgres -p postgres -P SiteID=123', shell=True)