Invoking AWS Lambda from Genesys Cloud Architect Data Action

Architect & Flows
1

How should I properly to configure the IAM role for a Lambda function invoked via a Genesys Cloud Architect Data Action?

I am writing a Go service to deploy these resources but hitting a 403 Forbidden error from the Lambda service. The Data Action uses the aws.lambda.invoke integration. My current IAM policy allows lambda:InvokeFunction but the execution fails. Do I need a resource-based policy on the Lambda function itself to allow the Genesys Cloud service principal?

2

This looks like a permissions mismatch between the Genesys Cloud integration credentials and the target Lambda’s execution environment. The aws.lambda.invoke data action relies on the IAM user or role configured within the AWS integration profile in Genesys Cloud. If that profile uses an IAM User, the user needs explicit lambda:InvokeFunction permissions. If it uses IAM Roles (via AssumeRole), the trust policy on the Lambda’s execution role must allow the specific AWS account/role from Genesys Cloud to assume it, and the Lambda function itself might need a resource-based policy if cross-account.

However, the 403 often stems from the Lambda execution role lacking permissions to write to CloudWatch Logs, causing the invocation to fail during startup, or the Genesys Cloud AWS integration profile having incorrect region settings.

First, verify the IAM policy attached to the identity used by the Genesys Cloud AWS integration. It must include:

{
 "Version": "2012-10-17",
 "Statement": [
 {
 "Effect": "Allow",
 "Action": "lambda:InvokeFunction",
 "Resource": "arn:aws:lambda:eu-west-1:123456789012:function:YourFunctionName"
 }
 ]
}

If the Lambda is in a different AWS account than the Genesys Cloud integration’s AWS account, you must add a resource-based policy to the Lambda function:

{
 "Version": "2012-10-17",
 "Statement": [
 {
 "Effect": "Allow",
 "Principal": {
 "AWS": "arn:aws:iam::GENESYS_ACCOUNT_ID:role/GENESYS_ROLE_NAME"
 },
 "Action": "lambda:InvokeFunction",
 "Resource": "arn:aws:lambda:eu-west-1:YOUR_ACCOUNT_ID:function:YourFunctionName"
 }
 ]
}

Also, ensure the Lambda execution role has logs:CreateLogGroup, logs:CreateLogStream, and logs:PutLogEvents. Without these, the Lambda fails to initialize, and Genesys Cloud reports a generic invocation error that can look like a 403. Check the CloudWatch Logs for the Lambda function for specific runtime errors. The documentation states: “The AWS Lambda function must have permissions to write to CloudWatch Logs.” This is a common oversight.

3

Check your resource-based policy on the Lambda. The suggestion above mentions execution roles, but you likely need a permission policy attached directly to the function allowing the Genesys Cloud principal. Here is the JSON snippet:

{
 "Effect": "Allow",
 "Principal": { "AWS": "arn:aws:iam::123456789:role/GenesysIntegrationRole" },
 "Action": "lambda:InvokeFunction",
 "Resource": "arn:aws:lambda:eu-west-1:123456789:function:MyAuditFunc"
}