converts ansible.cfg settings to shell environment variables

ansible-cfg2env

#!/bin/env python3

import os
import re
import yaml
import ast
import pprint
import configparser
import subprocess
import argparse
import textwrap
from shlex import quote

def val2env(cfg, val, name, _from):
    global args
    if args.c:
        ftmstr = "{}setenv {} {}"
    else:
        fmtstr = "{}export {}={}"

    try:
        if cfg['env'][-1]['name'][0] == '_':
            return "# Skipping '{}' -- for internal use only.".format(name)
    except:
        pass

    if 'default' not in cfg:
        df = 'None'
    else:    
        df = cfg['default']

    try:
        df = ast.literal_eval(df)
    except:
        try:
            df = ast.literal_eval("'" + df + "'")
        except:
            df = cfg['default']

    if _from == 'default':
        vj = df
    else:
        try:
            vj = ast.literal_eval(val)
        except:
            try:
                vj = ast.literal_eval("'" + val + "'")
            except:
                vj = val

    if "{}".format(vj) == "{}".format(df):
        print("# Skipping '{}' because specified value is the same as the default.".format(name))
        skp = '# '
    else:
        skp = ''

    if 'env' not in cfg:
        return "# No 'env' equivalent; skipping."
    if len(cfg['env']) == 0:
        return "# No 'env' equivalent; skipping."
    if isinstance(cfg['env'],list) and len(cfg['env']) > 0 and 'name' in cfg['env'][-1]:
        cfg_env_name = cfg['env'][-1]['name']
    else:
        cfg_env_name = '_missing_'

    iterable=False
    try:
      iter(vj)
      if not isinstance(vj, str):
          iterable = True
    except:
      pass

    if vj == None:
        return fmtstr.format(skp, cfg_env_name, 'None')
    elif 'type' not in cfg:
        try:
            qvj = quote(vj)
            return fmtstr.format(skp, cfg_env_name, quote(vj))
        except:
            return fmtstr.format(skp, cfg_env_name, vj)
    elif cfg['type'] == 'pathspec':
        return fmtstr.format(skp, cfg_env_name, quote(':'.join(vj)) if iterable else quote("{}".format(vj)))
    elif cfg['type'] in ['bool', 'boolean']:
        return fmtstr.format(skp, cfg_env_name, 'None' if vj == None else 'True' if vj else 'False')
    elif cfg['type'] in ['list', 'pathlist']:
        return fmtstr.format(skp, cfg_env_name, quote(','.join(vj)) if iterable else quote("{}".format(vj)))
    elif cfg['type'] in ['dict']:
        return fmtstr.format(skp, cfg_env_name, quote("{}".format(vj)))
    else:
        return fmtstr.format(skp, cfg_env_name, quote("{}".format(vj)))

def main():
    global args

    parser = argparse.ArgumentParser(epilog=textwrap.dedent('''\
         ansible-cfg2env converts ansible configuration settings from ansible.cfg
         format to a format suitable to set the equivalent command shell environment
         variables. Given that Ansible ignores system level ansible.cfg files after
         finding a user's ~/.ansible.cfg (rather than combining settings from all
         found config files), we're now recommending that users use environment
         variables to override only those settings they need to change. Settings
         from environment variables take precedence over those from found
         ansible.cfg files.

         Typical usage:
           ansible-cfg2env -a > ~/.ansible.cfg.sh
           mv ~/.ansible.cfg ~/.ansible.cfg-$(date -r ~/.ansible.cfg +%Y-%m-%d)
           echo ". ~/.ansible.cfg.sh" >> ~/.bash_profile
           . ~/.ansible.cfg.sh
         '''),
         formatter_class=argparse.RawDescriptionHelpFormatter)

    parser.add_argument('-c', help='format for csh/tcsh instead of sh/ksh/bash.',
                              action='store_true', default=False)
    parser.add_argument('-a', help='include comments for all settings, not just those differing from their default values.',
                              action='store_true', default=False)
    args = parser.parse_args()
    # pprint.pprint(args)

    # `ansible-config list` produces yaml output that describes all
    # ansible configuration options.
    
    cfg_list = subprocess.run(['ansible-config', 'list'], stdout=subprocess.PIPE)
    cfg_ref = yaml.load(cfg_list.stdout.decode('utf-8'), Loader=yaml.SafeLoader)
    # print("{}".format(cfg_ref))
    
    cfg_dump = subprocess.run(['ansible-config', 'dump'], stdout=subprocess.PIPE)
    # print("{}".format(cfg_dump.stdout.decode('utf-8')))
    for line in cfg_dump.stdout.decode('utf-8').split("\n"):
        ma = re.match("(\w+)\(([^()]+)\) *= *(.*)", line)
        if ma:
           _name = ma.group(1)
           _from = ma.group(2)
           _val  = ma.group(3)
           if args.a or _from != 'default':
               print("### name: {}\n### from: {}\n###  val: {}".format(_name, _from, _val))
               if _name in cfg_ref:
                   print("# {}\n".format('\n# '.join(pprint.pformat(cfg_ref[_name]).splitlines())), end='')
                   print("{}\n".format(val2env(cfg_ref[_name], _val, _name, _from)))
               else:
                   print("# No config definition for '{}'.".format(_name))

if __name__ == '__main__':
    main()