cmdhelper

cmdhelper is a Python utility for writing command line scripts with a consistent style, default set of command line options, and common approach to logging.

cmdhelper provides:

• Parsing of command line options using either argparse or optparse.
• Setup of logging with the possibility to copy stdout or stderr into the logfile.
• Possibility to e-mail log messages upon completion with an option to send the e-mail only if a log message with a severity at or above a trigger level was recorded.
• Definition of a set of default options, including options to set verbosity and logging options.
• A utility function to run external commands whose output can be logged and parsed for error messages.
• A utility function for asking the user to confirm actions.

Example

A script that processes different commands with optional command arguments might include:

from cmdhelper import *

cmdHelper = CmdHelper('argparse', __version__)
cmdHelper.add_argument('cmd', help='command')
cmdHelper.add_argument('args', help='command arguments', nargs='*')
cmdHelper.add_option('-x', '--example', dest='value', default=None, help='sample option')
options = cmdHelper.parse()

try:
    # processing goes here
    pass

except Exception as e:
     handleError(e, options.debug)

Running the above code with --help will produce the following output:

usage: example.py [-h] [--version] [-i] [-v] [--debug] [--noscreen]
                  [--logfile LOGFILE] [--loglevel LOGLEVEL]
                  [--logseparator LOGSEPARATOR]
                  [--logtimestampfmt LOGTIMESTAMPFMT]  [--emailto EMAILTO]
                  [--emailsubject EMAILSUBJECT] [--emaillevel EMAILLEVEL]
                  [--emailtriglevel EMAILTRIGLEVEL] [-x VALUE]
                  cmd [args [args ...]]

positional arguments:
  cmd                   command
  args                  command arguments

optional arguments:
  -h, --help            show this help message and exit
  --version             show program's version number and exit
  -i, --interactive     enter interactive Python at completion
  -v, --verbose         verbose output
  --debug               debugging output
  --noscreen            disable logging output to screen
  --logfile LOGFILE     write logging information to this file (default: )
  --loglevel LOGLEVEL   logging level for logfile (default: INFO or DEBUG)
  --logseparator LOGSEPARATOR
                        message to write to logfile at beginning of new log
  --logtimestampfmt LOGTIMESTAMPFMT
                        timestamp format string (in logging formatter format)
  --emailto EMAILTO     email address receiving any log messages
  --emailsubject EMAILSUBJECT
                        subject for log e-mails
  --emaillevel EMAILLEVEL
                        logging level for e-mails (default: WARNING)
  --emailtriglevel EMAILTRIGLEVEL
                        trigger level for sending e-mails (default: None)
  -x VALUE, --example VALUE
                        sample option