ApproachingLimitSize.py

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

import os
from pathlib import Path

from cfnlint._typing import RuleMatches
from cfnlint.helpers import LIMITS
from cfnlint.rules import CloudFormationLintRule, RuleMatch
from cfnlint.template import Template


class LimitSize(CloudFormationLintRule):
    """Check Template Size"""

    id = "I1002"
    shortdesc = "Validate approaching the template size limit"
    description = "Check the size of the template is approaching the upper limit"
    source_url = "https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/cloudformation-limits.html"
    tags = ["limits"]

    def match(self, cfn: Template) -> RuleMatches:
        matches = []
        # Only check if the file exists. The template could be passed in using stdIn
        if cfn.filename:
            if Path(cfn.filename).is_file():
                statinfo = os.stat(cfn.filename)
                if (
                    LIMITS["threshold"] * LIMITS["template"]["body"]
                    < statinfo.st_size
                    <= LIMITS["template"]["body"]
                ):
                    message = (
                        "The template file size ({0} bytes) is approaching the limit"
                        " ({1} bytes)"
                    )
                    matches.append(
                        RuleMatch(
                            ["Template"],
                            message.format(
                                statinfo.st_size, LIMITS["template"]["body"]
                            ),
                        )
                    )
        return matches