Source code for gammapy.utils.scripts

# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""Utils to create scripts and command-line tools"""
import logging
import os.path
import sys
from pathlib import Path
import yaml

__all__ = ["read_yaml", "write_yaml", "make_path", "recursive_merge_dicts"]

def _configure_root_logger(level="info", format=None):
    """Configure root log level and format.

    This is a helper function that can be called form
    log = logging.getLogger()  # Get root logger

    # Set log level
    # level = getattr(logging, level.upper())
    numeric_level = getattr(logging, level.upper(), None)
    if not isinstance(numeric_level, int):
        raise ValueError(f"Invalid log level: {level}")

    # Format log handler
    if not format:
        # format = '%(asctime)s %(name)-12s %(levelname)-8s %(message)s'
        format = "%(levelname)-8s %(message)s [%(name)s]"
    formatter = logging.Formatter(format)

    # Not sure why there sometimes is a handler attached to the root logger,
    # and sometimes not, i.e. why this is needed:
    if len(log.handlers) == 0:
        handler = logging.StreamHandler(sys.stderr)


    return log

[docs]def read_yaml(filename, logger=None): """Read YAML file. Parameters ---------- filename : `~pathlib.Path` Filename logger : `~logging.Logger` Logger Returns ------- data : dict YAML file content as a dict """ path = make_path(filename) if logger is not None:"Reading {path}") text = path.read_text() return yaml.safe_load(text)
[docs]def write_yaml(dictionary, filename, logger=None, sort_keys=True): """Write YAML file. Parameters ---------- dictionary : dict Python dictionary filename : `~pathlib.Path` Filename logger : `~logging.Logger` Logger sort_keys : bool Whether to sort keys. """ text = yaml.safe_dump(dictionary, default_flow_style=False, sort_keys=sort_keys) path = make_path(filename) path.parent.mkdir(exist_ok=True) if logger is not None:"Writing {path}") path.write_text(text)
[docs]def make_path(path): """Expand environment variables on `~pathlib.Path` construction. Parameters ---------- path : str, `pathlib.Path` path to expand """ # TODO: raise error or warning if environment variables that don't resolve are used # e.g. "spam/$DAMN/ham" where `$DAMN` is not defined # Otherwise this can result in cryptic errors later on return Path(os.path.expandvars(path))
[docs]def recursive_merge_dicts(a, b): """Recursively merge two dictionaries. Entries in b override entries in a. The built-in update function cannot be used for hierarchical dicts, see: Parameters ---------- a : dict dictionary to be merged b : dict dictionary to be merged Returns ------- c : dict merged dict Examples -------- >>> from gammapy.utils.scripts import recursive_merge_dicts >>> a = dict(a=42, b=dict(c=43, e=44)) >>> b = dict(d=99, b=dict(c=50, g=98)) >>> c = recursive_merge_dicts(a, b) >>> print(c) {'a': 42, 'b': {'c': 50, 'e': 44, 'g': 98}, 'd': 99} """ c = a.copy() for k, v in b.items(): if k in c and isinstance(c[k], dict): c[k] = recursive_merge_dicts(c[k], v) else: c[k] = v return c