FindInMap.py

"""
Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
SPDX-License-Identifier: MIT-0
"""

from __future__ import annotations

from typing import Any

from cfnlint.jsonschema import ValidationResult, Validator
from cfnlint.rules.functions._BaseFn import BaseFn, singular_types


class FindInMap(BaseFn):
    """Check if FindInMap values are correct"""

    id = "E1011"
    shortdesc = "FindInMap validation of configuration"
    description = "Making sure the function is a list of appropriate config"
    source_url = "https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/intrinsic-function-reference-findinmap.html"
    tags = ["functions", "findinmap"]

    def __init__(self) -> None:
        super().__init__("Fn::FindInMap", ("array",) + singular_types)

    def schema(self, validator: Validator, instance: Any) -> dict[str, Any]:
        scalar_schema = {
            "functions": [
                "Fn::FindInMap",
                "Ref",
            ],
            "schema": {
                "type": ["string"],
            },
        }

        schema = {
            "type": "array",
            "minItems": 3,
            "maxItems": 3,
            "fn_items": [
                scalar_schema,
                scalar_schema,
                scalar_schema,
            ],
        }

        if validator.context.transforms.has_language_extensions_transform():
            scalar_schema["functions"] = [
                "Fn::FindInMap",
                "Fn::Join",
                "Fn::Sub",
                "Fn::If",
                "Fn::Select",
                "Fn::Length",
                "Fn::ToJsonString",
                "Ref",
            ]
            schema["maxItems"] = 4
            schema["fn_items"] = [
                scalar_schema,
                scalar_schema,
                scalar_schema,
                {
                    "functions": [],
                    "schema": {
                        "findinmap_parameters": True,
                        "type": ["object"],
                        "properties": {
                            "DefaultValue": {
                                "default_value": True,
                            }
                        },
                        "additionalProperties": False,
                        "required": ["DefaultValue"],
                    },
                },
            ]

        return schema

    def _default_value(
        self, validator: Validator, s: Any, instance: Any, schema: Any
    ) -> ValidationResult:
        validator = validator.evolve(
            context=validator.context.evolve(
                functions=["Ref"],
            ),
        )
        yield from validator.descend(
            instance,
            {
                "type": ("array",) + singular_types,
            },
        )

    def fn_findinmap(
        self, validator: Validator, s: Any, instance: Any, schema: Any
    ) -> ValidationResult:

        if validator.context.transforms.has_language_extensions_transform():
            # we have to use a special validator for this
            # as we don't want DefaultValue: !Ref AWS::NoValue
            # is valid
            mapping_validator = validator.extend(
                validators={
                    "default_value": self._default_value,
                },
            )(validator.schema)
            validator = mapping_validator.evolve(
                context=validator.context.evolve(
                    resources={},
                ),
                cfn=validator.cfn,
                function_filter=validator.function_filter,
                resolver=validator.resolver,
            )
            yield from super().validate(validator, s, instance, schema)
            return

        validator = validator.evolve(
            context=validator.context.evolve(
                resources={},
            )
        )
        yield from super().validate(validator, s, instance, schema)