osm_pla/config/config.py

   1 # -*- coding: utf-8 -*-
   2 # Copyright 2020 ArctosLabs Scandinavia AB
   3 #
   4 # Licensed under the Apache License, Version 2.0 (the "License");
   5 # you may not use this file except in compliance with the License.
   6 # You may obtain a copy of the License at
   7 #
   8 #    http://www.apache.org/licenses/LICENSE-2.0
   9 #
  10 # Unless required by applicable law or agreed to in writing, software
  11 # distributed under the License is distributed on an "AS IS" BASIS,
  12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
  13 # implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16 """Global configuration managed by environment variables."""
  17
  18 import logging
  19 import os
  20
  21 import pkg_resources
  22 import yaml
  23
  24 logger = logging.getLogger(__name__)
  25
  26
  27 class Config:
  28     def __init__(self, config_file: str = ''):
  29         self.conf = {}
  30         self._read_config_file(config_file)
  31         self._read_env()
  32
  33     def _read_config_file(self, config_file):
  34         if not config_file:
  35             path = 'pla.yaml'
  36             config_file = pkg_resources.resource_filename(__name__, path)
  37         with open(config_file) as f:
  38             self.conf = yaml.load(f)
  39
  40     def _read_env(self):
  41         for env in os.environ:
  42             if not env.startswith("OSMPLA_"):
  43                 continue
  44             elements = env.lower().split("_")
  45             if len(elements) < 3:
  46                 logger.warning(
  47                     "Environment variable %s=%s does not comply with required format. Section and/or field missing.",
  48                     env, os.getenv(env))
  49                 continue
  50             section = elements[1]
  51             field = '_'.join(elements[2:])
  52             value = os.getenv(env)
  53             if section not in self.conf:
  54                 self.conf[section] = {}
  55             self.conf[section][field] = value
  56
  57     def get(self, section, field=None):
  58         if not field:
  59             return self.conf[section]
  60         return self.conf[section][field]
  61
  62     def set(self, section, field, value):
  63         if section not in self.conf:
  64             self.conf[section] = {}
  65         self.conf[section][field] = value