A small wrapper around trafaret and yaml that does nice error reporting (python)
APACHE-2.0 License
:Status: Stable :Documentation: http://trafaret-config.readthedocs.io/
This is a wrapper that loads yaml and checks config using trafaret_ while keeping track of actual lines of file where error has happened. Additionally, it can pretty print the error.
Basic Usage:
.. code-block:: python
import argparse
import trafaret
from trafaret_config import commandline
TRAFARET = trafaret.Dict({'x': trafaret.String()})
def main():
ap = argparse.ArgumentParser()
commandline.standard_argparse_options(ap, default_config='config.yaml')
#
# define your command-line arguments here
#
options = ap.parse_args()
config = commandline.config_from_options(options, TRAFARET)
pprint.pprint(config)
Example output when there is an error in config (from a example.py
which
has better trafaret than example above)::
bad.yaml:3: smtp.port: value can't be converted to int
-> 'unknown'
bad.yaml:4: smtp.ssl_port: value can't be converted to int
-> 'NaN'
bad.yaml:5: port: value can't be converted to int
-> '???'
Help looks like this::
usage: example.py [-h] [-c CONFIG] [--print-config] [--print-config-vars] [-C]
optional arguments:
-h, --help show this help message and exit
-c CONFIG, --config CONFIG
Configuration file (default: 'config.yaml')
--print-config Print config as it is read after parsing and exit
--print-config-vars Print variables used in configuration file
-C, --check-config Check configuration and exit
Since trafaret-config 2.0 environment variables in the config are replaced by default, this means that config like this:
.. code-block:: yaml
url: http://${HOST}:$PORT/
Will get HOST
and PORT
variables insert from the environment, and if
variable does not exist, you will get the following error::
config.yaml:2: variable 'PORT' not found
-> 'http://${HOST}:$PORT/'
Low-level interface, without relying on argparse:
.. code-block:: python
import sys import trafaret from trafaret_config import ConfigError, read_and_validate
TRAFARET = trafaret.Dict({'x': trafaret.String()})
try: config = read_and_validate('config.yaml', TRAFARET) except ConfigError as e: e.output() sys.exit(1)
.. _trafaret: http://github.com/Deepwalker/trafaret
::
pip install trafaret-config==2.0.2
Licensed under either of
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.