AWS CDK Target Group

An AWS CDK construct for creating Application Load Balancer (ALB) Target Groups with health checks and conditional deregistration delays.

Overview

This CDK construct creates an Elastic Load Balancing V2 Target Group with the following features:

• VPC Integration: Imports VPC from an existing ECS stack
• Health Checks: Configurable HTTP health checks with custom paths
• Conditional Logic: Different deregistration delays for dev vs production environments
• Flexible Configuration: Parameterized port, protocol, and health check settings

Features

• ✅ HTTP/HTTPS protocol support
• ✅ Customizable health check endpoints
• ✅ Environment-specific deregistration delays (0s for dev, configurable for prod)
• ✅ Health check status codes 200-299
• ✅ Configurable health check intervals and timeouts
• ✅ CloudFormation outputs for target group ARN

Installation

pip install alb-target-group

Usage

from aws_cdk import Stack
from constructs import Construct
from alb_target_group import TargetGroupStack

class MyStack(Stack):
    def __init__(self, scope: Construct, construct_id: str, **kwargs):
        super().__init__(scope, construct_id, **kwargs)
        
        target_group = TargetGroupStack(
            self, "MyTargetGroup",
            ecs_stack_name="my-ecs-stack",
            health_check_path="/api/health",
            channel="prod",  # or "dev"
            port=80,
            protocol="HTTP",
            max_request_duration=300,
            health_threshold_count=2,
            health_check_timeout_seconds=5,
            health_check_interval_seconds=10
        )

Configuration Parameters

Parameter	Type	Description
ecs_stack_name	string	Name of the ECS stack to import VPC from
health_check_path	string	Path for health check endpoint (e.g., /api/health)
channel	string	Environment channel (dev or prod)
port	int	Target group port (e.g., 80, 443)
protocol	string	Protocol (HTTP or HTTPS)
max_request_duration	int	Max request duration in seconds (used for non-dev deregistration delay)
health_threshold_count	int	Number of consecutive successful health checks required
health_check_timeout_seconds	int	Health check timeout in seconds
health_check_interval_seconds	int	Health check interval in seconds

Environment Behavior

• Dev Environment (channel="dev"): Deregistration delay is set to 0 seconds for faster deployments
• Production Environment (any other channel): Deregistration delay uses the max_request_duration value

Outputs

The construct exports:

• TargetGroupArn: The ARN of the created target group

Requirements

• AWS CDK v2
• Python 3.7+