config.py

import functools
import logging.config

import mongoengine
import pydantic as p


logging.basicConfig()


class MongoDbDsn(p.AnyUrl):
    allowed_schemes = {'mongodb', 'mongodb+srv', 'mongomock'}


class SettingsBase(p.BaseSettings):
    ENVIRONMENT: str = 'dev'

    class Config:
        env_file = '.env'
        env_file_encoding = 'utf-8'


class Settings(SettingsBase):

    MONGODB_URL: MongoDbDsn = 'mongodb://localhost/...'
    SECRET_KEY: str = '...'

    EMAIL_HOST_USER: p.EmailStr = '...'
    EMAIL_HOST_PASSWORD: str = ''
    EMAIL_HOST: str = 'smtp.office365.com'
    EMAIL_PORT: int = 587

    # How many minutes the access codes are valid
    ACCESS_CODE_EXPIRATION_PERIOD = 10

    # Sharing-area maximum file size in bytes
    SHARING_AREA_MAX_FILE_SIZE = 8_000_000

    # For how many minutes the session cookie is valid (since the user made an API call)
    AUTH_COOKIE_LIFETIME = 60 * 8
    AUTH_COOKIE_SECURE = False
    AUTH_COOKIE_NAME = 'session'

    # Username for accessing docs; if empty -- docs are disabled
    DOCS_USERNAME: str = 'docs'
    # Password for accessing docs; if empty -- docs are not password protected
    DOCS_PASSWORD: str = 'pass'

    UPDATE_DB_BASE_URL: p.AnyUrl = "..."
    AZURE_OAUTH: dict = {
        "authority": "https://login.microsoftonline.com/...",
        "client_id": "...",
        "scope": [ "api://.../.default" ],
        "secret": "...",
        "endpoint": "https://graph.microsoft.com/v1.0/users",
    }

    LOGGING: dict = {
        'version': 1,
        'disable_existing_loggers': False,
        'formatters': {
            'verbose': {
                'format': '[%(asctime)s] %(levelname)s %(name)s:%(lineno)s - %(message)s',
                'datefmt': '%Y-%m-%d %H:%M:%S',
            },
            'simple': {
                'format': '%(levelname)s %(asctime)s %(message)s',
                'datefmt': '%H:%M:%S',
            },
        },
        'handlers': {
            'console': {
                'level': 'INFO',
                'formatter': 'simple',
                'class': 'logging.StreamHandler',
            },
            'console_debug': {
                'level': 'DEBUG',
                'formatter': 'verbose',
                'class': 'logging.StreamHandler',
            },
            'mongodb': {
                'level': 'INFO',
                'formatter': 'verbose',
                'class': '...',
                # For now we don't compress the logs for humans to be able to easily analyze them
                'compress': False,
            },
        },
        'loggers': {
            '': {
                'handlers': ['console', 'mongodb'],
                'level': 'NOTSET',
            },
        }
    }


class SettingsProd(Settings):
    UPDATE_DB_BASE_URL: p.AnyUrl = "..."
    # The docs are disabled on prod
    DOCS_USERNAME: str = ''


class SettingsStaging(Settings):
    UPDATE_DB_BASE_URL: p.AnyUrl = "..."


class SettingsDev(Settings):

    # The docs are not password protected in dev environment
    DOCS_PASSWORD: str = ''


class SettingsTest(Settings):
    MONGODB_URL: MongoDbDsn = 'mongomock://localhost'
    LOGGING: dict = {
        'version': 1,
        'disable_existing_loggers': False,
        'formatters': {
            'simple': {
                'format': '%(levelname)s %(asctime)s %(message)s',
                'datefmt': '%H:%M:%S',
            },
        },
        'handlers': {
            'console': {
                'level': 'WARNING',
                'formatter': 'simple',
                'class': 'logging.StreamHandler',
            },
        },
        'loggers': {
            '': {
                'handlers': ['console'],
            },
        }
    }

    class Config:
        # We don't want tests to use env variables/files
        env_file = None
        env_prefix = '~'


@functools.cache
def get_settings() -> Settings:
    # https://rednafi.github.io/digressions/python/2020/06/03/python-configs.html
    environment = SettingsBase().ENVIRONMENT

    settings_class = {
        'dev': SettingsDev,
        'staging': SettingsStaging,
        'prod': SettingsProd,
        'testing': SettingsTest,
    }.get(environment.lower())

    if not settings_class:
        raise RuntimeError(f'Invalid `ENVIRONMENT`: {environment!r}')

    settings = settings_class()

    mongoengine.register_connection(mongoengine.DEFAULT_CONNECTION_NAME, host=settings.MONGODB_URL)

    logging.config.dictConfig(settings.LOGGING)

    return settings