sqspoll.sh

#!/usr/bin/env bash
set -e

for x in "$@"; do
    case $x in
        --help|-h|help)
            echo "Usage:"
            echo "$0 <options>"
            echo "   -h         this help message"
            echo "   -v         verbose output"
            echo "   --timeout= sets the timeout to wait for new messages"
            echo "   --queue=   sets the queue url"
            echo "   --run=     the command to run (the body of the sqs message will be sent to stdin of this command)"
            echo "   --count=   exit after x number of messages"
            echo "   --loop=    exit after x number of timeouts"
            echo "   --region=  specify the aws region for the queue url"
            exit
            ;;
        -v)
            VERBOSE=1
            ;;
        --timeout=*)
            TIMEOUT=$(echo $x | cut -d= -f2)
            ;;
        --region=*)
            AWS_REGION=$(echo $x | cut -d= -f2)
            ;;
        --queue=*)
            QUEUE_URL=$(echo $x | cut -d= -f2)
            ;;
        --run=*)
            RUN_CMD=$(echo $x | cut -d= -f2)
            ;;
        --count=*)
            COUNT=$(echo $x | cut -d= -f2)
            ;;
        --loop=*)
            LOOP=$(echo $x | cut -d= -f2)
            ;;
    esac
done
: ${AWS_REGION:?"You must provide the AWS region with --region"}
: ${QUEUE_URL:?"You must provide a queue url with --queue"}
: ${RUN_CMD:?"You must provide a run command with --run"}
: ${VERBOSE:="0"}
: ${TIMEOUT:="10"}
: ${COUNT:=""}
: ${LOOP:=""}

function log () {
    [[ $VERBOSE == 1 ]] && logerr $@
    return 0
}
function logerr () {
    (>&2 echo $@)
    return 0
}

set +e

log "Queue: $QUEUE_URL"
log "Timeout = $TIMEOUT"
while (true); do
    logerr -n .
    MESSAGES=$(aws --region "$AWS_REGION" sqs receive-message --queue-url "$QUEUE_URL" --wait-time-seconds "$TIMEOUT" --max-number-of-messages 1)
    if [[ "$MESSAGES" != "" ]]; then
        MESSAGE=$(echo $MESSAGES | jq '.Messages[]' -r)
        RECEIPT=$(echo $MESSAGE | jq '.ReceiptHandle' -r)
        BODY=$(echo $MESSAGE | jq '.Body' -r)
        log
        log "Receipt: $RECEIPT"
        log "Got Message:"
        log "$BODY"
        (echo "$BODY" | $RUN_CMD) > /dev/null 2>&1
        SUCCESS=$?
        if [ "$SUCCESS" == "0" ]; then
            aws --region "$AWS_REGION" sqs delete-message --queue-url "$QUEUE_URL" --receipt-handle "$RECEIPT"
            logerr -n √
        else
            logerr -n X
        fi
        if [[ $COUNT != "" ]]; then
            let COUNT--
            log "Count: $COUNT"
            (( $COUNT < 1 )) && exit
        fi
    fi
    if [[ $LOOP != "" ]]; then
        let LOOP--
        log "Loop: $LOOP"
        (( $LOOP < 1 )) && exit
    fi
done