Creating a CloudWatch Metrics from the Athena Query results - amazon-web-services

Question

My Requirement
I want to create a CloudWatch-Metric from Athena query results.
Example
I want to create a metric like user_count of each day.
In Athena, I will write an SQL query like this
select date,count(distinct user) as count from users_table group by 1
In the Athena editor I can see the result, but I want to see these results as a metric in Cloudwatch.
CloudWatch-Metric-Name ==> user_count
Dimensions ==> Date,count
If I have this cloudwatch metric and dimensions, I can easily create a Monitoring Dashboard and send send alerts
Can anyone suggest a way to do this?

Answer 1

You can use CloudWatch custom widgets, see "Run Amazon Athena queries" in Samples.

Answer 2

It's somewhat involved, but you can use a Lambda for this. In a nutshell:
Setup your query in Athena and make sure it works using the Athena console.
Create a Lambda that:
Runs your Athena query
Pulls the query results from S3
Parses the query results
Sends the query results to CloudWatch as a metric
Use EventBridge to run your Lambda on a recurring basis
Here's an example Lambda function in Python that does step #2. Note that the Lamda function will need IAM permissions to run queries in Athena, read the results from S3, and then put a metric into Cloudwatch.
import time
import boto3
query = 'select count(*) from mytable'
DATABASE = 'default'
bucket='BUCKET_NAME'
path='yourpath'
def lambda_handler(event, context):
#Run query in Athena
client = boto3.client('athena')
output = "s3://{}/{}".format(bucket,path)
# Execution
response = client.start_query_execution(
QueryString=query,
QueryExecutionContext={
'Database': DATABASE
},
ResultConfiguration={
'OutputLocation': output,
}
)
#S3 file name uses the QueryExecutionId so
#grab it here so we can pull the S3 file.
qeid = response["QueryExecutionId"]
#occasionally the Athena hasn't written the file
#before the lambda tries to pull it out of S3, so pause a few seconds
#Note: You are charged for time the lambda is running.
#A more elegant but more complicated solution would try to get the
#file first then sleep.
time.sleep(3)
###### Get query result from S3.
s3 = boto3.client('s3');
objectkey = path + "/" + qeid + ".csv"
#load object as file
file_content = s3.get_object(
Bucket=bucket,
Key=objectkey)["Body"].read()
#split file on carriage returns
lines = file_content.decode().splitlines()
#get the second line in file
count = lines[1]
#remove double quotes
count = count.replace("\"", "")
#convert string to int since cloudwatch wants numeric for value
count = int(count)
#post query results as a CloudWatch metric
cloudwatch = boto3.client('cloudwatch')
response = cloudwatch.put_metric_data(
MetricData = [
{
'MetricName': 'MyMetric',
'Dimensions': [
{
'Name': 'DIM1',
'Value': 'dim1'
},
],
'Unit': 'None',
'Value': count
},
],
Namespace = 'MyMetricNS'
)
return response
return