vpc_config | Patterned Designs Documentation

Type object({ subnet_ids = list(string) security_group_ids = list(string) })

Default null

Module lambda-function

VPC configuration for private network access

VPC Configuration Structure

vpc_config = {
  subnet_ids         = ["subnet-abc123", "subnet-def456"]
  security_group_ids = ["sg-123456"]
}

When to Use VPC

Access to RDS, ElastiCache, or other VPC resources
Compliance requirements for data isolation
Integration with on-premises resources via VPN/Direct Connect

Important Considerations

Cold starts: VPC-enabled functions have longer cold starts
Internet access: Requires NAT Gateway for outbound internet
IP addresses: Functions use Elastic Network Interfaces (ENIs)
Concurrency: ENI limits may affect scaling

Best Practices

Use private subnets for Lambda functions
Create dedicated security groups for Lambda
Place functions in multiple AZs for availability
Consider AWS PrivateLink for AWS service access

Full Module Example

module "lambda_function" {
  source  = "registry.patterneddesigns.ca/patterneddesigns/lambda-function/aws"
  version = "0.1.0"

  # vpc_config
  vpc_config = "..."

  # Other required inputs
  function_name = my-resource
  runtime = python3.9
  handler = example-value
  source_path = /path/to/resource
}