"""
Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
SPDX-License-Identifier: MIT-0
"""
from cfnlint.rules import CloudFormationLintRule, RuleMatch
class TaskDefinitionEssentialContainer(CloudFormationLintRule):
"""Check ECS TaskDefinition ContainerDefinitions Property Specifies at least one Essential Container"""
id = "E3042"
shortdesc = "Check at least one essential container is specified"
description = (
"Check that every TaskDefinition specifies at least one essential container"
)
source_url = "https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-ecs-taskdefinition-containerdefinitions.html#cfn-ecs-taskdefinition-containerdefinition-essential"
tags = ["properties", "ecs", "task", "container", "fargate"]
def match(self, cfn):
"""Check at least one essential container is specified"""
matches = []
results = cfn.get_resource_properties(
["AWS::ECS::TaskDefinition", "ContainerDefinitions"]
)
for result in results:
path = result["Path"]
has_essential_container = False
for container in result["Value"]:
if "Essential" in container:
if container["Essential"]:
has_essential_container = True
else:
pass
else:
# If 'Essential' is not specified, it defaults to an essential container
has_essential_container = True
if not has_essential_container:
error_message = (
f"No essential containers defined for {'/'.join(map(str, path))}"
)
rule_match = RuleMatch(path, error_message)
matches.append(rule_match)
return matches