config.py

import json
import logging.config
import pathlib

import jsonschema

logger = logging.getLogger(__name__)

ERROR_REPORT_CONFIG_SCHEMA = {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "definitions": {
        "email-params": {
            "type": "object",
            "properties": {
                "from": {"type": "string"},
                "reply_to": {"type": "string"},
                "to": {"$ref": "#/definitions/string-or-array"},
                "cc": {"$ref": "#/definitions/string-or-array"},
                "hostname": {"type": "string"},
                "port": {"type": "integer"},
                "username": {"type": "string"},
                "password": {"type": "string"},
                "starttls": {"type": "boolean"},
            },
            "required": [
                "from",
                "to",
                "hostname",
            ],
            "additionalProperties": False,
        },
        "string-or-array": {
            "oneOf": [
                {"type": "string"},
                {"type": "array", "items": {"type": "string"}, "minItems": 1},
            ]
        },
        "influx-db-params": {
            "type": "object",
            "properties": {
                "ssl": {"type": "boolean"},
                "hostname": {"type": "string"},
                "port": {"type": "integer"},
                "username": {"type": "string"},
                "password": {"type": "string"},
                "database": {"type": "string"},
                "measurement": {"type": "string"},
            },
            "required": [
                # ssl, port are optional
                "hostname",
                "username",
                "password",
                "database",
                "measurement",
            ],
            "additionalProperties": False,
        },
    },
    "type": "object",
    "properties": {
        "email": {"$ref": "#/definitions/email-params"},
        "inventory": {
            "type": "array",
            "items": {"type": "string", "format": "uri"},
            "minItems": 1,
        },
        "influx": {"$ref": "#/definitions/influx-db-params"},
        "exclude-interfaces": {
            "type": "array",
            "items": {
                "type": "array",
                "prefixItems": [
                    {"type": "string"},
                    {"type": "string"},
                ],
            },
        },
    },
    "required": ["email", "influx"],
    "additionalProperties": False,
}


def load(config_file: pathlib.Path):
    """
    loads, validates and returns configuration parameters

    :param config_file: filename (file-like object, opened for reading)
    :return: a dict containing configuration parameters
    :raises: json.JSONDecodeError, jsonschema.ValidationError
    """

    config = json.loads(config_file.read_text())
    jsonschema.validate(config, ERROR_REPORT_CONFIG_SCHEMA)

    # convert str addresses into list of str
    if isinstance(config["email"]["to"], str):
        config["email"]["to"] = [config["email"]["to"]]
    if isinstance(config["email"].get("cc"), str):
        config["email"]["cc"] = [config["email"]["cc"]]
    return config