Python subprocess AttributeError

Question

I have the following issue:

 try:
 with subprocess.check_call(query):
 return 1
 except ValueError:
 return -1

This code runs a shell script and it's working so far. The script returns 0. Nevertheless I got this error:

with subprocess.check_call(query):
AttributeError: 'int' object has no attribute '__exit__'

so there has to be someting wrong with my try/except block.

Answer 1

subprocess.check_call() returns an int status code 0, not a context manager. You cannot use it in a with statement.

return subprocess.check_call(query)

Just return the return value of that call. Note that it will not raise a ValueError exception either; it'll raise CalledProcessError if the process exits with a non-zero status code.

Perhaps what you really wanted to use was subprocess.call().