Best Practices

This guide covers recommended practices for deploying and operating the GenAI IDP Accelerator with Terraform.

Deployment Best Practices

Environment Management

Use Separate Environments:

# terraform/environments/dev/terraform.tfvars
environment = "dev"
region = "us-east-1"

# Reduced resources for development
lambda_memory_size = 512
lambda_timeout = 60
enable_detailed_monitoring = false

Consistent Tagging:

locals {
  common_tags = {
    Environment = var.environment
    Project     = "genai-idp-accelerator"
    Owner       = var.owner
    Terraform   = "true"
  }
}

State Management

Remote State Backend:

terraform {
  backend "s3" {
    bucket         = "terraform-state-${var.environment}"
    key            = "idp-accelerator/terraform.tfstate"
    region         = "us-east-1"
    encrypt        = true
    dynamodb_table = "terraform-locks"
  }
}

State Locking:

resource "aws_dynamodb_table" "terraform_locks" {
  name           = "terraform-locks"
  billing_mode   = "PAY_PER_REQUEST"
  hash_key       = "LockID"

  attribute {
    name = "LockID"
    type = "S"
  }
}

Security Best Practices

IAM Permissions

Least Privilege Principle:

resource "aws_iam_policy" "lambda_policy" {
  name = "${var.environment}-idp-lambda-policy"

  policy = jsonencode({
    Version = "2012-10-17"
    Statement = [
      {
        Effect = "Allow"
        Action = [
          "textract:DetectDocumentText",
          "textract:AnalyzeDocument"
        ]
        Resource = "*"
      },
      {
        Effect = "Allow"
        Action = [
          "s3:GetObject",
          "s3:PutObject"
        ]
        Resource = "${aws_s3_bucket.documents.arn}/*"
      }
    ]
  })
}

Data Protection

Encryption at Rest:

resource "aws_s3_bucket_server_side_encryption_configuration" "documents" {
  bucket = aws_s3_bucket.documents.id

  rule {
    apply_server_side_encryption_by_default {
      sse_algorithm = "AES256"
    }
  }
}

Encryption in Transit:

• Use HTTPS for all API endpoints
• Enable SSL/TLS for data transfer
• Use VPC endpoints where possible

Performance Best Practices

Lambda Optimization

Memory and Timeout Settings:

resource "aws_lambda_function" "document_processor" {
  memory_size = 1024  # Adjust based on workload
  timeout     = 300   # 5 minutes for document processing

  environment {
    variables = {
      POWERTOOLS_LOG_LEVEL = "INFO"
    }
  }
}

Connection Reuse:

import boto3

# Initialize clients outside handler for reuse
s3_client = boto3.client('s3')
textract_client = boto3.client('textract')

def lambda_handler(event, context):
    # Use pre-initialized clients
    response = textract_client.detect_document_text(...)

Storage Optimization

S3 Lifecycle Policies:

resource "aws_s3_bucket_lifecycle_configuration" "documents_lifecycle" {
  bucket = aws_s3_bucket.documents.id

  rule {
    id     = "transition_to_ia"
    status = "Enabled"

    transition {
      days          = 30
      storage_class = "STANDARD_IA"
    }

    transition {
      days          = 90
      storage_class = "GLACIER"
    }
  }
}

Monitoring Best Practices

CloudWatch Configuration

Log Groups:

resource "aws_cloudwatch_log_group" "lambda_logs" {
  name              = "/aws/lambda/${var.environment}-idp-processor"
  retention_in_days = var.log_retention_days
}

Alarms:

resource "aws_cloudwatch_metric_alarm" "lambda_errors" {
  alarm_name          = "${var.environment}-lambda-errors"
  comparison_operator = "GreaterThanThreshold"
  evaluation_periods  = "2"
  metric_name         = "Errors"
  namespace           = "AWS/Lambda"
  period              = "300"
  statistic           = "Sum"
  threshold           = "5"

  alarm_actions = [aws_sns_topic.alerts.arn]
}

Operational Best Practices

Deployment Process

Validation Steps:

1. Run terraform plan and review changes
2. Test in development environment first
3. Use gradual rollout for staging
4. Monitor deployment metrics

Rollback Strategy:

# Keep previous state file versions
terraform state pull > terraform.tfstate.backup

# Quick rollback if needed
terraform apply -target=aws_lambda_function.processor \
  -var="lambda_version=previous"

Documentation

Infrastructure Documentation:

• Document all custom configurations
• Maintain architecture diagrams
• Keep runbooks updated
• Record operational procedures

Backup and Recovery

State File Backup:

resource "aws_s3_bucket_versioning" "state_bucket_versioning" {
  bucket = aws_s3_bucket.terraform_state.id
  versioning_configuration {
    status = "Enabled"
  }
}

Data Backup:

resource "aws_dynamodb_table" "documents" {
  point_in_time_recovery {
    enabled = true
  }
}

Testing Best Practices

Infrastructure Testing

Validation:

# Validate Terraform configuration
terraform validate

# Check formatting
terraform fmt -check

# Security scanning
tfsec .

Integration Testing:

# Test deployment in staging
terraform plan -var-file="staging.tfvars"
terraform apply -var-file="staging.tfvars"

# Run smoke tests
./scripts/smoke-tests.sh staging

Troubleshooting

Common Issues

Permission Errors:

• Check IAM policies and roles
• Verify service-linked roles exist
• Review resource policies

Resource Limits:

• Check AWS service quotas
• Monitor resource utilization
• Request quota increases if needed

State Issues:

• Use terraform refresh to sync state
• Import existing resources if needed
• Handle state lock conflicts

Debugging Tools

Terraform Debugging:

export TF_LOG=DEBUG
terraform apply

AWS CLI Debugging:

aws logs describe-log-groups --debug
aws lambda get-function --function-name processor --debug

Maintenance

Regular Tasks

Weekly:

• Review CloudWatch alarms and metrics
• Update documentation as needed

Monthly:

• Review and update IAM permissions
• Analyze performance metrics
• Plan capacity adjustments

Quarterly:

• Security review and updates
• Disaster recovery testing
• Architecture review

Updates and Patches

Terraform Updates:

# Update Terraform version
terraform version
terraform init -upgrade

# Update provider versions
terraform init -upgrade

Lambda Runtime Updates:

resource "aws_lambda_function" "processor" {
  runtime = "python3.11"  # Keep updated
}

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For more detailed information, see:

• Environment Setup
• Monitoring Guide
• Troubleshooting Guide