import json
import pymysql
import boto3
import base64

secret_name = "serverless-app-rds-secret"
region_name = "ap-northeast-2"

def get_secret():    
    session = boto3.session.Session()
    client = session.client(
        service_name = 'secretsmanager',
        region_name = region_name
    )

    get_secret_value_response = client.get_secret_value(
        SecretId=secret_name
    )

    if 'SecretString' in get_secret_value_response:
        secret = get_secret_value_response['SecretString']
        return secret
    else:
        decoded_binary_secret = base64.b64decode(get_secret_value_response['SecretBinary'])
        return decoded_binary_secret

secret = get_secret()
json_secret = json.loads(secret)

db = pymysql.connect(
    host = 'YOUR RDS PROXY ENDPOINT', 
    user = json_secret['username'], 
    password = json_secret['password']
    )

cursor = db.cursor()

def lambda_handler(event, context):
    cursor.execute("select now()")
    result = cursor.fetchone()

    db.commit()
    
    return {
        'statusCode': 200,
        'body': json.dumps(result[0].isoformat())
    }