cloudformation_include: TypeError when Lambda Layers defined with Condition in template #36140
Description
Describe the bug
When including a CloudFormation template via CfnInclude, if a Lambda function defines its Layers property using a Fn::If intrinsic function, CDK throws: TypeError: props.layers?.forEach is not a function.
Regression Issue
- Select this option if this issue appears to be a regression.
Last Known Working CDK Library Version
2.226.0
Expected Behavior
cdk synth should succeed and produce a valid CloudFormation template.
$ cdk synth
Conditions:
MyCondition: true
Resources:
MyFunctionRole:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Version: "2012-10-17"
Statement:
- Action: sts:AssumeRole
Effect: Allow
Principal:
Service: lambda.amazonaws.com
MyFunction:
Type: AWS::Lambda::Function
Properties:
Code:
ZipFile: ""
Handler: lambda_function.lambda_handler
Layers:
Fn::If:
- MyCondition
- []
- - arn:123456789012:lambda:aaa:123456789012:layer:example-layer:1
Role:
Fn::GetAtt: MyFunctionRole.Arn
Runtime: python3.12
Parameters:
BootstrapVersion:
Type: AWS::SSM::Parameter::Value<String>
Default: /cdk-bootstrap/hnb659fds/version
Description: Version of the CDK Bootstrap resources in this environment, automatically retrieved from SSM Parameter Store. [cdk:skip]Current Behavior
cdk synth fails
$ cdk synth
<..snip..>
TypeError: props.layers?.forEach is not a function
at new CfnFunction (/workspaces/my-workspace/node_modules/aws-cdk-lib/aws-lambda/lib/lambda.generated.js:1:86020)
at Function._fromCloudFormation (/workspaces/my-workspace/node_modules/aws-cdk-lib/aws-lambda/lib/lambda.generated.js:1:82530)
at CfnInclude.getOrCreateResource (/workspaces/my-workspace/node_modules/aws-cdk-lib/cloudformation-include/lib/cfn-include.js:1:15441)
at new CfnInclude (/workspaces/my-workspace/node_modules/aws-cdk-lib/cloudformation-include/lib/cfn-include.js:1:2904)
at /workspaces/my-workspace/src/app.ts:5:1
at ViteNodeRunner.runModule (file:///workspaces/my-workspace/node_modules/vite-node/dist/client.mjs:397:4)
at ViteNodeRunner.directRequest (file:///workspaces/my-workspace/node_modules/vite-node/dist/client.mjs:375:3)
at ViteNodeRunner.cachedRequest (file:///workspaces/my-workspace/node_modules/vite-node/dist/client.mjs:189:11)
at ViteNodeRunner.executeFile (file:///workspaces/my-workspace/node_modules/vite-node/dist/client.mjs:162:10)
at CAC.run (file:///workspaces/my-workspace/node_modules/vite-node/dist/cli.mjs:102:28)Reproduction Steps
app.ts
import * as cdk from "aws-cdk-lib";
const app = new cdk.App();
const stack = new cdk.Stack(app, "MyStack");
new cdk.cloudformation_include.CfnInclude(stack, "MyCfnInclude", {
templateFile: "my.template.yml",
});my.template.yml
Conditions:
MyCondition: true
Resources:
MyFunction:
Type: AWS::Lambda::Function
Properties:
Role: !GetAtt "MyFunctionRole.Arn"
Handler: lambda_function.lambda_handler
Layers: !If
- MyCondition
- []
- ["arn:123456789012:lambda:aaa:123456789012:layer:example-layer:1"]
Code:
ZipFile: ""
Runtime: python3.12
MyFunctionRole:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Version: "2012-10-17"
Statement:
- Action: sts:AssumeRole
Effect: Allow
Principal:
Service: lambda.amazonaws.comPossible Solution
No response
Additional Information/Context
Using vite-node to run CDK app
AWS CDK Library version (aws-cdk-lib)
2.227.0
AWS CDK CLI version
2.1022.0
Node.js Version
v22.21.1
OS
Linux 6.6.87.2 (WSL2)
Language
TypeScript
Language Version
TypeScript 5.9.2
Other information
No response