feat(config): Add config module

I added this mostly so that we use a consistent location to download EPW files to. I have verified that this module will work well on both Windows and Unix-based systems.

ladybug/config.json

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+{
+ "__comment__": "Add full paths to folders (eg. C:/epw_data, /usr/local/epw_data).",
+ "default_epw_folder": ""
+}

ladybug/config.py

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+"""Ladybug configurations.
+
+Import this into every module where access configurations are needed.
+
+Usage:
+ from ladybug.config import folders
+ print(folders.default_epw_folder)
+ folders.default_epw_folder = "C:/epw_data"
+"""
+import os
+import sys
+import json
+
+
+class Folders(object):
+ """Ladybug folders.
+
+ Args:
+ config_file: The path to the config.json file from which folders are loaded.
+ If None, the config.json module included in this package will be used.
+ Default: None.
+ mute: If False, the paths to the various folders will be printed as they
+ are found. If True, no printing will occur upon initialization of this
+ class. Default: True.
+
+ Properties:
+ * default_epw_folder
+ * config_file
+ * mute
+ """
+
+ def __init__(self, config_file=None, mute=True):
+ # set the mute value
+ self.mute = bool(mute)
+
+ # load paths from the config JSON file 
+ self.config_file = config_file
+
+ @property
+ def default_epw_folder(self):
+ """Get or set the path to the default folder where EPW files are stored."""
+ return self._default_epw_folder
+
+ @default_epw_folder.setter
+ def default_epw_folder(self, path):
+ if not path: # check the default location for epw files
+ path = self._find_default_epw_folder()
+
+ self._default_epw_folder = path
+
+ if not self.mute and self._default_epw_folder:
+ print('Path to the default epw folder is set to: '
+ '{}'.format(self._default_epw_folder))
+
+ @property 
+ def config_file(self):
+ """Get or set the path to the config.json file from which folders are loaded.
+ 
+ Setting this to None will result in using the config.json module included
+ in this package.
+ """
+ return self._config_file
+
+ @config_file.setter
+ def config_file(self, cfg):
+ if cfg is None:
+ cfg = os.path.join(os.path.dirname(__file__), 'config.json')
+ self._load_from_file(cfg)
+ self._config_file = cfg
+
+ def _load_from_file(self, file_path):
+ """Set all of the the properties of this object from a config JSON file.
+ 
+ Args:
+ file_path: Path to a JSON file containing the file paths. A sample of this
+ JSON is the config.json file within this package.
+ """
+ # check the default file path
+ assert os.path.isfile(file_path), \
+ ValueError('No file found at {}'.format(file_path))
+
+ # set the default paths to be all blank
+ default_path = {
+ "default_epw_folder": r''
+ }
+
+ with open(file_path, 'r') as cfg:
+ try:
+ paths = json.load(cfg)
+ except Exception as e:
+ print('Failed to load paths from {}.\nThey will be set to defaults '
+ 'instead\n{}'.format(file_path, e))
+ else:
+ for key, p in paths.items():
+ if not key.startswith('__') and p.strip():
+ default_path[key] = p.strip()
+
+ # set paths for the default_epw_folder
+ self.default_epw_folder = default_path["default_epw_folder"]
+
+ @staticmethod
+ def _find_default_epw_folder():
+ """Find the the default EPW folder in its usual location.
+ 
+ An attempt will be made to create the directory if it does not already exist.
+ """
+ try: # windows
+ sim_folder = os.path.join(os.environ['USERPROFILE'], 'ladybug')
+ except KeyError: # mac and linux
+ sim_folder = os.path.join(os.environ['HOME'], 'ladybug')
+ if not os.path.isdir(sim_folder):
+ try:
+ os.makedirs(sim_folder)
+ except Exception as e:
+ raise OSError('Failed to create default epw '
+ 'folder: %s\n%s' % (sim_folder, e))
+ return sim_folder
+
+
+"""Object possesing all key folders within the configuration."""
+folders = Folders()

tests/config_test.py

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+# coding=utf-8
+from ladybug.config import folders
+
+import pytest
+
+
+def test_config_init():
+ """Test the initialization of the config module and basic properties."""
+ assert hasattr(folders, 'default_epw_folder')
+ assert isinstance(folders.default_epw_folder, str)
+