Concurrently execute a lambda function for warming purposes

lambda-concurrent.sh

#!/bin/bash

# This attempts to concurrently execute an AWS Lambda function. WIP.
# After execution, roughly NUM_EXECUTION containers will be ready
# to accept requests.

# More advanced strategies are out there. Check out @lambdacult on twitter, for example.

AWS_LAMBDA_FUNCTION_NAME=LambdaInfo
NUM_EXECUTIONS=3

TMP_FILE=$(mktemp)

# get 7-day max invocations in 1 minute
# todo: use this value to set the number of executions
aws cloudwatch get-metric-statistics --namespace AWS/Lambda --dimensions Name=FunctionName,Value=LambdaInfo --metric-name Invocations --start-time $(date -v -2d -u +"%Y-%m-%dT%H:%M:%SZ") --end-time $(date -u +"%Y-%m-%dT%H:%M:%SZ") --statistics Maximum --period 86400

for i in `seq 1 $NUM_EXECUTIONS`;
do
  echo "[$i] Executing $AWS_LAMBDA_FUNCTION_NAME..."
	  aws lambda invoke --invocation-type Event --function-name $AWS_LAMBDA_FUNCTION_NAME --payload '' --qualifier \$LATEST --log-type None /dev/null >> $TMP_FILE 2>&1 &
done

wait

echo "Finished executing $AWS_LAMBDA_FUNCTION_NAME!"

cat $TMP_FILE
rm $TMP_FILE