# Licensed under a 3-clause BSD style license - see LICENSE.rst
"""Utilities to create scripts and command-line tools."""
import codecs
import os.path
import warnings
from base64 import urlsafe_b64encode
from pathlib import Path
from uuid import uuid4
import yaml
from gammapy.utils.check import add_checksum, verify_checksum
__all__ = [
"get_images_paths",
"make_path",
"read_yaml",
"recursive_merge_dicts",
"write_yaml",
]
PATH_DOCS = Path(__file__).resolve().parent / ".." / ".." / "docs"
SKIP = ["_static", "_build", "_checkpoints", "docs/user-guide/model-gallery/"]
[docs]def get_images_paths(folder=PATH_DOCS):
"""Generator yields a Path for each image used in notebook.
Parameters
----------
folder : str
Folder where to search.
"""
for i in Path(folder).rglob("images/*"):
if not any(s in str(i) for s in SKIP):
yield i.resolve()
[docs]def read_yaml(filename, logger=None, checksum=False):
"""Read YAML file.
Parameters
----------
filename : `~pathlib.Path`
Filename.
logger : `~logging.Logger`
Logger.
checksum : bool
Whether to perform checksum verification. Default is False.
Returns
-------
data : dict
YAML file content as a dictionary.
"""
path = make_path(filename)
if logger is not None:
logger.info(f"Reading {path}")
text = path.read_text()
data = yaml.safe_load(text)
checksum_str = data.pop("checksum", None)
if checksum:
index = text.find("checksum")
if not verify_checksum(text[:index], checksum_str):
warnings.warn(f"Checksum verification failed for {filename}.", UserWarning)
return data
[docs]def write_yaml(dictionary, filename, logger=None, sort_keys=True, checksum=False):
"""Write YAML file.
Parameters
----------
dictionary : dict
Python dictionary.
filename : `~pathlib.Path`
Filename.
logger : `~logging.Logger`, optional
Logger. Default is None.
sort_keys : bool, optional
Whether to sort keys. Default is True.
checksum : bool, optional
Whether to add checksum keyword. Default is False.
"""
text = yaml.safe_dump(dictionary, default_flow_style=False, sort_keys=sort_keys)
if checksum:
text = add_checksum(text, sort_keys=sort_keys)
path = make_path(filename)
path.parent.mkdir(exist_ok=True)
if logger is not None:
logger.info(f"Writing {path}")
path.write_text(text)
def make_name(name=None):
"""Make a dataset name."""
if name is None:
name = urlsafe_b64encode(codecs.decode(uuid4().hex, "hex")).decode()[:8]
while name[0] == "_":
name = urlsafe_b64encode(codecs.decode(uuid4().hex, "hex")).decode()[:8]
if not isinstance(name, str):
raise ValueError(
"Name argument must be a string, "
f"got '{name}', which is of type '{type(name)}'"
)
return name
[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
if path is None:
return None
else:
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:
http://stackoverflow.com/questions/3232943/update-value-of-a-nested-dictionary-of-varying-depth/3233356#3233356
Parameters
----------
a : dict
Dictionary to be merged.
b : dict
Dictionary to be merged.
Returns
-------
c : dict
Merged dictionary.
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