Join.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
from cfnlint.jsonschema.protocols import Validator
from cfnlint.rules.functions._BaseFn import BaseFn


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

    id = "E1022"
    shortdesc = "Join validation of parameters"
    description = "Making sure the join function is properly configured"
    source_url = "https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/intrinsic-function-reference-join.html"
    tags = ["functions", "join"]

    def __init__(self) -> None:
        super().__init__("Fn::Join", ("string",), resolved_rule="W1032")
        self.child_rules.update(
            {
                "I1022": None,
            }
        )

    def schema(self, validator, instance) -> dict[str, Any]:
        return {
            "type": "array",
            "maxItems": 2,
            "minItems": 2,
            "fn_items": [
                {
                    "schema": {
                        "type": ["string"],
                    },
                },
                {
                    "functions": [
                        "Fn::Cidr",
                        "Fn::FindInMap",
                        "Fn::GetAtt",
                        "Fn::If",
                        "Fn::Split",
                        "Ref",
                    ],
                    "schema": {
                        "type": ["array"],
                        "fn_items": {
                            "functions": [
                                "Fn::Base64",
                                "Fn::FindInMap",
                                "Fn::GetAtt",
                                "Fn::If",
                                "Fn::ImportValue",
                                "Fn::Join",
                                "Fn::Select",
                                "Fn::Sub",
                                "Fn::Transform",
                                "Ref",
                            ],
                            "schema": {
                                "type": ["string"],
                            },
                        },
                    },
                },
            ],
        }

    def fn_join(
        self, validator: Validator, s: Any, instance: Any, schema: Any
    ) -> ValidationResult:
        validator = validator.evolve(
            context=validator.context.evolve(strict_types=True)
        )
        errs = list(super().validate(validator, s, instance, schema))
        if errs:
            yield from iter(errs)

        for rule in self.child_rules.values():
            if rule is None or not hasattr(rule, "validate"):
                continue

            yield from rule.validate(validator, s, instance, schema)