how to reference iam role (created in parent stack) in nested stack - nested

Question

how to reference the iam role (created in the parent stack) in a nested stack
Here are my yml files for the parent and child stack
I used the !Ref and !GetAtt, none of them are working.
Parent Stack:
AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description:
SAM Template for Nested application resources
Resources:
Layer:
Type: AWS::Lambda::LayerVersion
Properties:
CompatibleRuntimes:
- nodejs16.x
Content:
S3Bucket: bucketName
S3Key: Key
Description: My layer
LayerName: lambdaLayer
LicenseInfo: MIT
SourceIAMRole:
Type: AWS::IAM::Role
Properties:
RoleName: source-lambda-iam-omni-agent-role
AssumeRolePolicyDocument:
Version: '2012-10-17'
Statement:
- Sid: ''
Effect: Allow
Principal:
Service: lambda.amazonaws.com
Action: sts:AssumeRole
Policies:
- PolicyName: translate-policy
PolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Action:
- comprehend:DetectDominantLanguage
- translate:TranslateText
Resource: '*'
- PolicyName: invokeLambda-sns-sqs-sm-policy
PolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Action:
- lambda:InvokeAsync
- lambda:InvokeFunction
- sns:Publish
- iam:ListRoles
- iam:GetRole
- secretsmanager:GetSecretValue
- secretsmanager:ListSecrets
- secretsmanager:UpdateSecret
- sqs:*
Resource: '*'
- PolicyName: sts-policy
PolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Action:
- sts:AssumeRole
Resource: '*'
- PolicyName: write-cloudwatch-logs-policy
PolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Action:
- logs:CreateLogStream
- logs:CreateLogGroup
- logs:PutLogEvents
Resource: '*'
ManagedPolicyArns:
- arn:aws:iam::aws:policy/service-role/AWSLambdaKinesisExecutionRole
- arn:aws:iam::aws:policy/service-role/AWSLambdaVPCAccessExecutionRole
- arn:aws:iam::aws:policy/AmazonS3FullAccess
- arn:aws:iam::aws:policy/AmazonAPIGatewayInvokeFullAccess
- arn:aws:iam::aws:policy/AmazonDynamoDBFullAccess
- arn:aws:iam::aws:policy/AmazonConnect_FullAccess
config:
Type: AWS::Serverless::Application
Properties:
Location: customerconfig.yml
Parameters:
LayerARN: !Ref Layer
IAMRole: !Ref SourceIAMRole
DependsOn:
- Layer
- SourceIAMRole
I did pass the IAM role to the nested stack in the parameter as you can see above in the parent stack. Now I need to pass the ARN created in the parent stack to child (nested) stack
Child stack (Nested)
AWSTemplateFormatVersion: 2010-09-09
Description:
Start from scratch starter project
Transform: AWS::Serverless-2016-10-31
Globals:
Function:
Runtime: nodejs16.x
Timeout: 15
CodeUri: ./
VpcConfig:
SecurityGroupIds:
- sg-005941cb59bd3c74e
SubnetIds:
- subnet-083b8c9bc31cefb69
- subnet-0f77f5b03c7fc1bc7
Layers:
- !Ref LayerARN
MemorySize: 128
Parameters:
LayerARN:
Type: String
IAMRole:
Type: String
Resources:
helloFromLambdaFunction:
Type: AWS::Serverless::Function
Properties:
Role: !GetAtt IAMRole.Arn
Handler: api/getapplicationconfig.handler
Description: A Lambda function that returns a static string.

Answer 1

I did manage to make it work,
While passing the parameters to nested stack, for the IAM role we will use
!GetAtt SourceIAMRole.Arn.
config:
Type: AWS::Serverless::Application
Properties:
Location: customerconfig.yml
Parameters:
LayerARN: !Ref Layer
IAMRole: !GetAtt SourceIAMRole.Arn