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|
"""Usage:
quick_example.py tcp [<host>] [--force] [--timeout=<seconds>]
quick_example.py serial <port> [--baud=<rate>] [--timeout=<seconds>]
quick_example.py -h | --help | --version
"""
from docopt import docopt
def load_json_config():
import json
# Pretend that we load the following JSON file:
source = """
{"--force": true,
"--timeout": "10",
"--baud": "9600"}
"""
return json.loads(source)
def load_ini_config():
try: # Python 2
from ConfigParser import ConfigParser
from StringIO import StringIO
except ImportError: # Python 3
from configparser import ConfigParser
from io import StringIO
# By using `allow_no_value=True` we are allowed to
# write `--force` instead of `--force=true` below.
config = ConfigParser(allow_no_value=True)
# Pretend that we load the following INI file:
source = """
[default-arguments]
--force
--baud=19200
<host>=localhost
"""
# ConfigParser requires a file-like object and
# no leading whitespace.
config_file = StringIO("\n".join(source.split()))
config.readfp(config_file)
# ConfigParsers sets keys which have no value
# (like `--force` above) to `None`. Thus we
# need to substitute all `None` with `True`.
return dict(
(key, True if value is None else value)
for key, value in config.items("default-arguments")
)
def merge(dict_1, dict_2):
"""Merge two dictionaries.
Values that evaluate to true take priority over falsy values.
`dict_1` takes priority over `dict_2`.
"""
return dict(
(str(key), dict_1.get(key) or dict_2.get(key))
for key in set(dict_2) | set(dict_1)
)
if __name__ == "__main__":
json_config = load_json_config()
ini_config = load_ini_config()
arguments = docopt(__doc__, version="0.1.1rc")
# Arguments take priority over INI, INI takes priority over JSON:
result = merge(arguments, merge(ini_config, json_config))
from pprint import pprint
print("\nJSON config:")
pprint(json_config)
print("\nINI config:")
pprint(ini_config)
print("\nResult:")
pprint(result)
|
