7. Monitoring Setup

import json
import boto3
from datetime import datetime, timedelta
from boto3.dynamodb.conditions import Key

def lambda_handler(event, context):
    print("Custom Metrics Publisher Started")
    
    # Initialize AWS clients
    dynamodb = boto3.resource('dynamodb')
    cloudwatch = boto3.client('cloudwatch')
    
    try:
        # Get risk assessment data
        risk_metrics = get_risk_metrics(dynamodb)
        
        # Get certification metrics
        cert_metrics = get_certification_metrics(dynamodb)
        
        # Publish custom metrics
        publish_metrics(cloudwatch, risk_metrics, cert_metrics)
        
        return {
            'statusCode': 200,
            'body': json.dumps('Custom metrics published successfully')
        }
        
    except Exception as e:
        print(f'Error publishing metrics: {str(e)}')
        return {
            'statusCode': 500,
            'body': json.dumps(f'Error: {str(e)}')
        }

def get_risk_metrics(dynamodb):
    """Get risk assessment metrics from DynamoDB"""
    table = dynamodb.Table('RiskAssessments')
    
    # Get latest user risk assessments
    response = table.scan(
        FilterExpression='AssessmentType = :type',
        ExpressionAttributeValues={':type': 'User Risk Assessment'}
    )
    
    risk_levels = {'LOW': 0, 'MEDIUM': 0, 'HIGH': 0, 'CRITICAL': 0}
    
    for item in response['Items']:
        risk_level = item.get('RiskLevel', 'LOW')
        if risk_level in risk_levels:
            risk_levels[risk_level] += 1
    
    return risk_levels

def get_certification_metrics(dynamodb):
    """Get certification metrics from DynamoDB"""
    table = dynamodb.Table('AccessCertifications')
    
    response = table.scan()
    
    total_certifications = len(response['Items'])
    recent_certifications = 0
    
    # Count recent certifications (last 30 days)
    thirty_days_ago = (datetime.now() - timedelta(days=30)).isoformat()
    
    for item in response['Items']:
        cert_date = item.get('CertificationDate', '')
        if cert_date > thirty_days_ago:
            recent_certifications += 1
    
    return {
        'total': total_certifications,
        'recent': recent_certifications
    }

def publish_metrics(cloudwatch, risk_metrics, cert_metrics):
    """Publish custom metrics to CloudWatch"""
    
    # Publish risk metrics
    for risk_level, count in risk_metrics.items():
        cloudwatch.put_metric_data(
            Namespace='IdentityGovernance',
            MetricData=[
                {
                    'MetricName': f'{risk_level}RiskUserCount',
                    'Value': count,
                    'Unit': 'Count',
                    'Timestamp': datetime.now()
                }
            ]
        )
    
    # Publish certification metrics
    cloudwatch.put_metric_data(
        Namespace='IdentityGovernance',
        MetricData=[
            {
                'MetricName': 'TotalCertifications',
                'Value': cert_metrics['total'],
                'Unit': 'Count',
                'Timestamp': datetime.now()
            },
            {
                'MetricName': 'RecentCertifications',
                'Value': cert_metrics['recent'],
                'Unit': 'Count',
                'Timestamp': datetime.now()
            }
        ]
    )
    
    print(f"Published metrics: Risk={risk_metrics}, Cert={cert_metrics}")