imap-notify

#!/usr/bin/env bash

if [ -z "$4" ]; then
  echo "Imap idle listener"
  echo "Usage: $0 user@domain.com password server:993 /usr/bin/notify_command"
  exit 1
fi

user=$1
password=$2
server=$3
command=$4

start_idle () {
  echo ". login \"$user\" \"$password\""
  echo ". select inbox"
  echo ". idle"
  while true; do
    sleep 600;
    echo "done"
    echo ". noop"
    echo ". idle"
  done
}

# Start ssl connection
echo "Starting imap idle client, logging in as $user at $server"
while read -r line ; do
  # Debug info, turn this off for silent operation
  echo "$line"
  if echo "$line" | grep -Eq ". [1-9][0-9]? EXISTS"; then
    echo "New mail received, executing $command"
    $command
  fi
  if echo "$line" | grep -Eq ". [1-9][0-9]? EXPUNGE"; then
    echo "Mail removed from server, executing $command"
    $command
  fi
done < <(openssl s_client -crlf -quiet -connect "$server" 2>/dev/null < <(start_idle))