"""
Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
SPDX-License-Identifier: MIT-0
"""
from cfnlint.helpers import RESOURCE_SPECS
from cfnlint.rules import CloudFormationLintRule, RuleMatch
class Value(CloudFormationLintRule):
"""Check if Outputs have string values"""
id = "E6003"
shortdesc = "Outputs have values of strings"
description = "Making sure the outputs have strings as values"
source_url = "https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/outputs-section-structure.html"
tags = ["outputs"]
def __init__(self):
"""Init"""
super().__init__()
self.resourcetypes = []
def initialize(self, cfn):
resourcespecs = RESOURCE_SPECS[cfn.regions[0]]
self.resourcetypes = resourcespecs["ResourceTypes"]
def match(self, cfn):
matches = []
template = cfn.template
getatts = cfn.search_deep_keys("Fn::GetAtt")
refs = cfn.search_deep_keys("Ref")
# If using a getatt make sure the attribute of the resource
# is not of Type List
for getatt in getatts:
if getatt[0] == "Outputs":
if getatt[2] == "Value":
obj = getatt[-1]
if isinstance(obj, list):
objtype = (
template.get("Resources", {}).get(obj[0], {}).get("Type")
)
if objtype:
attribute = (
self.resourcetypes.get(objtype, {})
.get("Attributes", {})
.get(obj[1], {})
.get("Type")
)
if attribute == "List":
if getatt[-4] != "Fn::Join" and getatt[-3] != 1:
message = "Output {0} value {1} is of type list"
matches.append(
RuleMatch(
getatt,
message.format(getatt[1], "/".join(obj)),
)
)
# If using a ref for an output make sure it isn't a
# Parameter of Type List
for ref in refs:
if ref[0] == "Outputs":
if ref[2] == "Value":
obj = ref[-1]
if isinstance(obj, str):
param = template.get("Parameters", {}).get(obj)
if param:
paramtype = param.get("Type")
if paramtype:
if paramtype.startswith("List<"):
if ref[-4] != "Fn::Join" and ref[-3] != 1:
message = "Output {0} value {1} is of type list"
matches.append(
RuleMatch(ref, message.format(ref[1], obj))
)
return matches