user-data

#!/bin/bash

function get_contents() {
    if [ -x "$(which curl)" ]; then
        curl -s -f "$1"
    elif [ -x "$(which wget)" ]; then
        wget "$1" -O -
    else
        die "No download utility (curl, wget)"
    fi
}

BUCKET_NAME="<CHANGE ME!!>"

readonly SCRIPT_NAME="aws-install-ssm-agent"
SCRIPT_URL="https://s3.amazonaws.com/$BUCKET_NAME/ssm/$SCRIPT_NAME"

cd /tmp
FILE_SIZE=0
MAX_RETRY_COUNT=3
RETRY_COUNT=0

while [ $RETRY_COUNT -lt $MAX_RETRY_COUNT ] ; do
  echo AWS-UpdateLinuxAmi: Downloading script from $SCRIPT_URL
  get_contents "$SCRIPT_URL" > "$SCRIPT_NAME"
  FILE_SIZE=$(du -k /tmp/$SCRIPT_NAME | cut -f1)
  echo AWS-UpdateLinuxAmi: Finished downloading script, size: $FILE_SIZE
  if [ $FILE_SIZE -gt 0 ]; then
    break
  else
    if [[ $RETRY_COUNT -lt MAX_RETRY_COUNT ]]; then
      RETRY_COUNT=$((RETRY_COUNT+1));
      echo AWS-UpdateLinuxAmi: FileSize is 0, retryCount: $RETRY_COUNT
    fi
  fi 
done

if [ $FILE_SIZE -gt 0 ]; then
  chmod +x "$SCRIPT_NAME"
  echo AWS-UpdateLinuxAmi: Running UpdateSSMAgent script now ....
  ./"$SCRIPT_NAME"
else
  echo AWS-UpdateLinuxAmi: Unable to download script, quitting ....
fi