Create one Lambda function for stop and the other for starting the rds instances respectively.

Start Function code:

import boto3
import os
import sys
import time
from datetime import datetime, timezone
from time import gmtime, strftime

def start_rds_all():
region=os.environ[‘REGION’]
key=os.environ[‘KEY’]
value=os.environ[‘VALUE’]
client = boto3.client(‘rds’, region_name=region)
response = client.describe_db_instances()

v_readReplica=[]
for i in response[‘DBInstances’]:
readReplica=i[‘ReadReplicaDBInstanceIdentifiers’]
v_readReplica.extend(readReplica)

for i in response[‘DBInstances’]:
#The if condition below filters aurora clusters from single instance databases as boto3 commands defer to start the aurora clusters.
if i[‘Engine’] not in [‘aurora-mysql’,‘aurora-postgresql’]:
#The if condition below filters Read replicas.
if i[‘DBInstanceIdentifier’] not in v_readReplica and len(i[‘ReadReplicaDBInstanceIdentifiers’]) == 0:
arn=i[‘DBInstanceArn’]
resp2=client.list_tags_for_resource(ResourceName=arn)
#check if the RDS instance is part of the Auto-Shutdown group.
if 0==len(resp2[‘TagList’]):
print(‘DB Instance {0} is not part of autoshutdown’.format(i[‘DBInstanceIdentifier’]))
else:
for tag in resp2[‘TagList’]:
if tag[‘Key’]==key and tag[‘Value’]==value:
if i[‘DBInstanceStatus’] == ‘available’:
print(‘{0} DB instance is already available’.format(i[‘DBInstanceIdentifier’]))
elif i[‘DBInstanceStatus’] == ‘stopped’:
client.start_db_instance(DBInstanceIdentifier = i[‘DBInstanceIdentifier’])
print(‘Started DB Instance {0}’.format(i[‘DBInstanceIdentifier’]))
elif i[‘DBInstanceStatus’]==‘starting’:
print(‘DB Instance {0} is already in starting state’.format(i[‘DBInstanceIdentifier’]))
elif i[‘DBInstanceStatus’]==‘stopping’:
print(‘DB Instance {0} is in stopping state. Please wait before starting’.format(i[‘DBInstanceIdentifier’]))
elif tag[‘Key’]!=key and tag[‘Value’]!=value:
print(‘DB instance {0} is not part of autoshutdown’.format(i[‘DBInstanceIdentifier’]))
elif len(tag[‘Key’]) == 0 or len(tag[‘Value’]) == 0:
print(‘DB Instance {0} is not part of autoShutdown’.format(i[‘DBInstanceIdentifier’]))
elif i[‘DBInstanceIdentifier’] in v_readReplica:
print(‘DB Instance {0} is a Read Replica.’.format(i[‘DBInstanceIdentifier’]))
else:
print(‘DB Instance {0} has a read replica. Cannot shutdown & start a database with Read Replica’.format(i[‘DBInstanceIdentifier’]))

response=client.describe_db_clusters()
for i in response[‘DBClusters’]:
cluarn=i[‘DBClusterArn’]
resp2=client.list_tags_for_resource(ResourceName=cluarn)
if 0==len(resp2[‘TagList’]):
print(‘DB Cluster {0} is not part of autoshutdown’.format(i[‘DBClusterIdentifier’]))
else:
for tag in resp2[‘TagList’]:
if tag[‘Key’]==key and tag[‘Value’]==value:
if i[‘Status’] == ‘available’:
print(‘{0} DB Cluster is already available’.format(i[‘DBClusterIdentifier’]))
elif i[‘Status’] == ‘stopped’:
client.start_db_cluster(DBClusterIdentifier=i[‘DBClusterIdentifier’])
print(‘Started Cluster {0}’.format(i[‘DBClusterIdentifier’]))
elif i[‘Status’]==‘starting’:
print(‘cluster {0} is already in starting state.’.format(i[‘DBClusterIdentifier’]))
elif i[‘Status’]==‘stopping’:
print(‘cluster {0} is in stopping state. Please wait before starting’.format(i[‘DBClusterIdentifier’]))
elif tag[‘Key’] != key and tag[‘Value’] != value:
print(‘DB Cluster {0} is not part of autoshutdown’.format(i[‘DBClusterIdentifier’]))
else:
print(‘DB Instance {0} is not part of autoShutdown’.format(i[‘DBClusterIdentifier’]))

def lambda_handler(event, context):
start_rds_all()

Stop Function code:

import boto3
import os
import sys
import time
from datetime import datetime, timezone
from time import gmtime, strftime

def shut_rds_all():
    region=os.environ['REGION']
    key=os.environ['KEY']
    value=os.environ['VALUE']

    
    client = boto3.client('rds', region_name=region)
    response = client.describe_db_instances()
    v_readReplica=[]
    for i in response['DBInstances']:
        readReplica=i['ReadReplicaDBInstanceIdentifiers']
        v_readReplica.extend(readReplica)
    
    for i in response['DBInstances']:
#The if condition below filters aurora clusters from single instance databases as boto3 commands defer to stop the aurora clusters.
        if i['Engine'] not in ['aurora-mysql','aurora-postgresql']:
#The if condition below filters Read replicas.
            if i['DBInstanceIdentifier'] not in v_readReplica and len(i['ReadReplicaDBInstanceIdentifiers']) == 0:
                arn=i['DBInstanceArn']
                resp2=client.list_tags_for_resource(ResourceName=arn)
#check if the RDS instance is part of the Auto-Shutdown group.
                if 0==len(resp2['TagList']):
                    print('DB Instance {0} is not part of autoshutdown'.format(i['DBInstanceIdentifier']))
                else:
                    for tag in resp2['TagList']:
#If the tags match, then stop the instances by validating the current status.
                        if tag['Key']==key and tag['Value']==value:
                            if i['DBInstanceStatus'] == 'available':
                                client.stop_db_instance(DBInstanceIdentifier = i['DBInstanceIdentifier'])
                                print('stopping DB instance {0}'.format(i['DBInstanceIdentifier']))
                            elif i['DBInstanceStatus'] == 'stopped':
                                print('DB Instance {0} is already stopped'.format(i['DBInstanceIdentifier']))
                            elif i['DBInstanceStatus']=='starting':
                                print('DB Instance {0} is in starting state. Please stop the cluster after starting is complete'.format(i['DBInstanceIdentifier']))
                            elif i['DBInstanceStatus']=='stopping':
                                print('DB Instance {0} is already in stopping state.'.format(i['DBInstanceIdentifier']))
                        elif tag['Key']!=key and tag['Value']!=value:
                            print('DB instance {0} is not part of autoshutdown'.format(i['DBInstanceIdentifier']))
                        elif len(tag['Key']) == 0 or len(tag['Value']) == 0:
                            print('DB Instance {0} is not part of auroShutdown'.format(i['DBInstanceIdentifier']))
            elif i['DBInstanceIdentifier'] in v_readReplica:
                print('DB Instance {0} is a Read Replica. Cannot shutdown a Read Replica instance'.format(i['DBInstanceIdentifier']))
            else:
                print('DB Instance {0} has a read replica. Cannot shutdown a database with Read Replica'.format(i['DBInstanceIdentifier']))

    response=client.describe_db_clusters()
    for i in response['DBClusters']:
        cluarn=i['DBClusterArn']
        resp2=client.list_tags_for_resource(ResourceName=cluarn)
        if 0==len(resp2['TagList']):
            print('DB Cluster {0} is not part of autoshutdown'.format(i['DBClusterIdentifier']))
        else:
            for tag in resp2['TagList']:
                if tag['Key']==key and tag['Value']==value:
                    if i['Status'] == 'available':
                        client.stop_db_cluster(DBClusterIdentifier=i['DBClusterIdentifier'])
                        print('stopping DB cluster {0}'.format(i['DBClusterIdentifier']))
                    elif i['Status'] == 'stopped':
                        print('DB Cluster {0} is already stopped'.format(i['DBClusterIdentifier']))
                    elif i['Status']=='starting':
                        print('DB Cluster {0} is in starting state. Please stop the cluster after starting is complete'.format(i['DBClusterIdentifier']))
                    elif i['Status']=='stopping':
                        print('DB Cluster {0} is already in stopping state.'.format(i['DBClusterIdentifier']))
                elif tag['Key'] != key and tag['Value'] != value:
                    print('DB Cluster {0} is not part of autoshutdown'.format(i['DBClusterIdentifier']))
                else:
                    print('DB Instance {0} is not part of auroShutdown'.format(i['DBClusterIdentifier']))

def lambda_handler(event, context):
    shut_rds_all()

Create Amazon EventBridge Rule:

In the EventBridge console, navigate to the Rule and create a rule. Provide the name, description, and the eventbus. Choose the rule type as ‘scheduled’ and click ‘continue’ to create the rule.

Under the schedule pattern, choose a specific time and enter the Cron expression. Click ‘next’. On the next page, select the target types as AWS Service. Choose your Lambda function (start/stop) that you want to trigger and enter your Lambda functions ARN. Select ‘Create’ at the bottom of the page to create the Rule. Now the EventBridge Rule will trigger your Lambda functions (start/stop).

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