markusressel/container-app-conf

#  Copyright (c) 2019 Markus Ressel
#  .
#  Permission is hereby granted, free of charge, to any person obtaining a copy
#  of this software and associated documentation files (the "Software"), to deal
#  in the Software without restriction, including without limitation the rights
#  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
#  copies of the Software, and to permit persons to whom the Software is
#  furnished to do so, subject to the following conditions:
#  .
#  The above copyright notice and this permission notice shall be included in all
#  copies or substantial portions of the Software.
#  .
#  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
#  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
#  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
#  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
#  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
#  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
#  SOFTWARE.
from typing import Type

from container_app_conf import ConfigEntry


class ListConfigEntry(ConfigEntry):
    """
    Config entry allowing to specify a list of items of specified type
    """

    def __init__(self, item_type: Type[ConfigEntry], key_path: [str], example: any = None,
                 description: str or None = None,
                 default: any = None,
                 required: bool = None,
                 secret: bool = None,
                 item_args: dict = None,
                 delimiter: str = None):
        """
        :param item_type: the type of the ConfigEntry to use for individual list items
        :param item_args: additional constructor arguments for the item_entry
        :param delimiter: delimiter to use for splitting items when specifying the list as a string
        :param key_path: list of yaml tree entries
        :param example: example str value
        :param description: a description of this list entry
        :param default: default value
        :param required: if None is allowed for this config entry
        """
        if item_args is None:
            item_args = {}

        # pass "secret" value to item if necessary
        if secret:
            item_args["secret"] = secret

        self._item_entry = item_type(key_path=key_path, **item_args)
        self.delimiter = delimiter if delimiter is not None else ","

        super().__init__(
            key_path=key_path,
            description=description,
            example=example,
            default=default,
            required=required,
            secret=secret
        )

    @property
    def example(self) -> any:
        if self.default is not None:
            return self.default

        if self._example is not None:
            return self._example

        single_example = self._item_entry.example
        return [single_example, single_example, single_example]

    def _value_to_type(self, value: any) -> [any] or None:
        """
        Tries to permissively convert the given value to a list of values.
        :param value: the value to parse
        :return: the parsed list
        """
        if not isinstance(value, list):
            value = str(value).split(self.delimiter)

        return list(map(lambda x: self._item_entry._value_to_type(x), filter(lambda x: x, value)))

    def _type_to_value(self, type: list or str) -> any:
        if type is None:
            return None
        if isinstance(type, str):
            return type
        str_items = list(map(lambda x: self._item_entry._type_to_value(x), type))
        return str_items