assume role policy

resource "aws_iam_role" "test_role" {
 name = "test_role"

 # Terraform's "jsonencode" function converts a
 # Terraform expression result to valid JSON syntax.
 assume_role_policy = jsonencode({
   Version = "2012-10-17"
   Statement = [
     {
       Action = "sts:AssumeRole"
       Effect = "Allow"
       Sid    = ""
       Principal = {
         Service = "ec2.amazonaws.com"
       }
     },
   ]
 })

 tags = {
   tag-key = "tag-value"
 }
}

AWS IAM role, AWS service roles, AWS IAM Roles Anywhere: [ list-roles | get-role | create-role | put-role-policy | create-service-linked-role | attach-role-policy | update-role | add-role-to-instance-profile ], aws ec2 describe-iam-instance-profile-associations ], IAM roles for EC2 instances, AWSServiceRoleForAutoScaling