Getting error while testing AWS Lambda function: "Invalid database identifier" - amazon-web-services

Question

Hi I'm getting error while testing lambda function like:
{
"errorMessage": "An error occurred (InvalidParameterValue) when calling the DescribeDBInstances operation: Invalid database identifier: <RDS instance id>",
"errorType": "ClientError",
"stackTrace": [
" File \"/var/task/lambda_function.py\", line 25, in lambda_handler\n db_instances = rdsClient.describe_db_instances(DBInstanceIdentifier=rdsInstanceId)['DBInstances']\n",
" File \"/var/runtime/botocore/client.py\", line 391, in _api_call\n return self._make_api_call(operation_name, kwargs)\n",
" File \"/var/runtime/botocore/client.py\", line 719, in _make_api_call\n raise error_class(parsed_response, operation_name)\n"
]
}
AND here is my lambda code :
import json
import boto3
import logging
import os
#Logging
LOGGER = logging.getLogger()
LOGGER.setLevel(logging.INFO)
#Initialise Boto3 for RDS
rdsClient = boto3.client('rds')
def lambda_handler(event, context):
#log input event
LOGGER.info("RdsAutoRestart Event Received, now checking if event is eligible. Event Details ==> ", event)
#Input event from the SNS topic originated from RDS event notifications
snsMessage = json.loads(event['Records'][0]['Sns']['Message'])
rdsInstanceId = snsMessage['Source ID']
stepFunctionInput = {"rdsInstanceId": rdsInstanceId}
rdsEventId = snsMessage['Event ID']
#Retrieve RDS instance ARN
db_instances = rdsClient.describe_db_instances(DBInstanceIdentifier=rdsInstanceId)['DBInstances']
db_instance = db_instances[0]
rdsInstanceArn = db_instance['DBInstanceArn']
# Filter on the Auto Restart RDS Event. Event code: RDS-EVENT-0154.
if 'RDS-EVENT-0154' in rdsEventId:
#log input event
LOGGER.info("RdsAutoRestart Event detected, now verifying that instance was tagged with auto-restart-protection == yes")
#Verify that instance is tagged with auto-restart-protection tag. The tag is used to classify instances that are required to be terminated once started.
tagCheckPass = 'false'
rdsInstanceTags = rdsClient.list_tags_for_resource(ResourceName=rdsInstanceArn)
for rdsInstanceTag in rdsInstanceTags["TagList"]:
if 'auto-restart-protection' in rdsInstanceTag["Key"]:
if 'yes' in rdsInstanceTag["Value"]:
tagCheckPass = 'true'
#log instance tags
LOGGER.info("RdsAutoRestart verified that the instance is tagged auto-restart-protection = yes, now starting the Step Functions Flow")
else:
tagCheckPass = 'false'
#log instance tags
LOGGER.info("RdsAutoRestart Event detected, now verifying that instance was tagged with auto-restart-protection == yes")
if 'true' in tagCheckPass:
#Initialise StepFunctions Client
stepFunctionsClient = boto3.client('stepfunctions')
# Start StepFunctions WorkFlow
# StepFunctionsArn is stored in an environment variable
stepFunctionsArn = os.environ['STEPFUNCTION_ARN']
stepFunctionsResponse = stepFunctionsClient.start_execution(
stateMachineArn= stepFunctionsArn,
name=event['Records'][0]['Sns']['MessageId'],
input= json.dumps(stepFunctionInput)
)
else:
LOGGER.info("RdsAutoRestart Event detected, and event is not eligible")
return {
'statusCode': 200
}
I'm trying to Stop an Amazon RDS database which starts automatically after 7 days. I'm following this AWS document: Field Notes: Stopping an Automatically Started Database Instance with Amazon RDS | AWS Architecture Blog
Can anyone help me?

Answer 1

The error message is saying: Invalid database identifier: <RDS instance id>"
It seems to be coming from this line:
db_instances = rdsClient.describe_db_instances(DBInstanceIdentifier=rdsInstanceId)['DBInstances']
The error message is saying that the rdsInstanceId variable contains <RDS instance id>, which seems to be an example value rather than a real value.
In looking at the code on Field Notes: Stopping an Automatically Started Database Instance with Amazon RDS | AWS Architecture Blog, it is asking you to create a test event that includes this message:
"Message": "{\"Event Source\":\"db-instance\",\"Event Time\":\"2020-07-09 15:15:03.031\",\"Identifier Link\":\"https://console.aws.amazon.com/rds/home?region=<region>#dbinstance:id=<RDS instance id>\",\"Source ID\":\"<RDS instance id>\",\"Event ID\":\"http://docs.amazonwebservices.com/AmazonRDS/latest/UserGuide/USER_Events.html#RDS-EVENT-0154\",\"Event Message\":\"DB instance started\"}",
If you look closely at that line, it includes this part to identify the Amazon RDS instance:
dbinstance:id=<RDS instance id>
I think that you are expected to modify the provided test event to fill-in your own values for anything in <angled brackets> (such as the Instance Id of your Amazon RDS instance).