apiVersion: v1
kind: ConfigMap
metadata:
  name: fluent-bit-sidecar-wrapper
  namespace: sparkns
  labels:
    app.kubernetes.io/name: fluent-bit
data:
  subprocess.sh: |
    MOUNT_PATH="/var/log/fluentd"
    FILE_TO_WATCH="$MOUNT_PATH/main-container-terminated"
    INITIAL_HEARTBEAT_TIMEOUT_THRESHOLD=120
    HEARTBEAT_TIMEOUT_THRESHOLD=30
    SLEEP_DURATION=5
    WAIT_BEFORE_TERMINATION=15

    echo "Waiting for file $FILE_TO_WATCH to appear..."
    start_wait=$(date +%s)
    echo "Start wait: $start_wait"

    #echo "Found file $FILE_TO_WATCH; watching for heartbeats..."

    # Waiting for the first heartbeat sent by Spark main container
    NOTFOUND_COUNT=0
    while ! [[ -f "$FILE_TO_WATCH" ]]; do
      elapsed_wait=$(expr $(date +%s) - $start_wait)
      echo "Elapsed Wait: $elapsed_wait"
      if [ "$elapsed_wait" -gt "$INITIAL_HEARTBEAT_TIMEOUT_THRESHOLD" ]; then
        echo "File $FILE_TO_WATCH not found after $INITIAL_HEARTBEAT_TIMEOUT_THRESHOLD seconds; aborting"
        terminate_main_process
        exit 1
      fi
      echo "Not found count: $NOTFOUND_COUNT"
      echo "Waiting..."
      sleep $SLEEP_DURATION;
      NOTFOUND_COUNT=$((NOTFOUND_COUNT+1))
    done;

    function terminate_main_process() {
      echo "TERMINATED PROCESS"
      fpid=`pidof fluent-bit`
      echo "Fluent-Bit pid: $fpid"
      echo "Killing process after sleeping for $WAIT_BEFORE_TERMINATION seconds"
      
      ps -ef | grep fluent
      sleep $WAIT_BEFORE_TERMINATION
      echo "Killing process $fpid"
      kill $fpid
    }

    # Waiting for the first heartbeat sent by Spark main container
    echo "Waiting for file $FILE_TO_WATCH to appear..."
    start_wait=$(date +%s)

    #echo "Found file $FILE_TO_WATCH; watching for heartbeats..."

    FOUND_COUNT=0
    while [[ -f "$FILE_TO_WATCH" ]]; do
        LAST_HEARTBEAT=$(stat -c %Y $FILE_TO_WATCH)
        ELAPSED_TIME_SINCE_AFTER_HEARTBEAT=$(expr $(date +%s) - $LAST_HEARTBEAT)

        echo "Last heartbeat: $LAST_HEARTBEAT"
        echo "Elapsed Time since after heartbeat: $ELAPSED_TIME_SINCE_AFTER_HEARTBEAT"

        if [ "$ELAPSED_TIME_SINCE_AFTER_HEARTBEAT" -gt "$HEARTBEAT_TIMEOUT_THRESHOLD" ]; then
          echo "Last heartbeat to file $FILE_TO_WATCH was more than $HEARTBEAT_TIMEOUT_THRESHOLD seconds ago at $LAST_HEARTBEAT; terminating"
          terminate_main_process
          exit 0
        fi

        echo "Found count: $FOUND_COUNT"
        echo "list files:"
        ls -l $FILE_TO_WATCH

        sleep $SLEEP_DURATION;
        FOUND_COUNT=$((FOUND_COUNT+1))

    done;

    echo "Outside of loop, main-container-terminated file no longer exists"
    ls -l $FILE_TO_WATCH
    
    # the file will be deleted once the fluentd container is terminated
    echo "The file $FILE_TO_WATCH doesn't exist anymore;"
    terminate_main_process
    exit 0

  wrapper.sh: |
    echo -n "AWS for Fluent Bit Container Image Version "
    cat /AWS_FOR_FLUENT_BIT_VERSION
    /fluent-bit/bin/fluent-bit -e /fluent-bit/firehose.so -e /fluent-bit/cloudwatch.so -e /fluent-bit/kinesis.so -c /fluent-bit/etc/fluent-bit.conf