python - bufsize must be an integer error while grepping a message

Question

I am running into following error while trying to grep for a message consisting of multipe lines in a log...can anyone provide inputs on how to overcome this error?

CODE:-

    print gerrit_commitmsg
    gerritlog = Popen('git','log','--grep','gerrit_commitmsg', stdout=PIPE, stderr=PIPE)
    print gerritlog

ERROR:-

Commit message:-

Build system changes

Build system changes to include packages in the build

Change-Id: I697558f01ae367d2baacdf2c7fcf1a03753edacd

Traceback (most recent call last):
  File "gerrits_in_workspace.py", line 87, in <module>
    main()
  File "gerrits_in_workspace.py", line 77, in main
    grep_commitmsg(gerrit_commitmsg)
  File "gerrits_in_workspace.py", line 48, in grep_commitmsg
    gerritlog = Popen('git','log','--grep','gerrit_commitmsg', stdout=PIPE, stderr=PIPE)
  File "/usr/lib/python2.7/subprocess.py", line 629, in __init__
    raise TypeError("bufsize must be an integer")

Answer 1

The subprocess.Popen class expects an argument list like this:

Popen(args, bufsize=0, ...)

So you're passing it:

• args = git
• bufsize = log

Hence the error (bufsize expects an integer value). The command vector needs to be a list, like this:

gerritlog = Popen(['git','log','--grep','gerrit_commitmsg'], stdout=PIPE, stderr=PIPE)