#!/bin/bash

STATE_OK=0
STATE_WARNING=1
STATE_CRITICAL=2
STATE_UNKNOWN=3

socket=$1

info=$(redis-cli -s $socket info replication)
lag=$(echo "$info" | grep master_last_io_seconds_ago | cut -d":" -f2 | sed -e "s/\s//g")
slave_offset=$(echo "$info" | grep slave_repl_offset | cut -d":" -f2 | sed -e "s/\s//g")
master_offset=$(echo "$info" | grep master_repl_offset | cut -d":" -f2 | sed -e "s/\s//g")
offset=$(($master_offset - $slave_offset))

exit_code=$?

if [[ $exit_code -ne 0 ]]; then
  echo "UNKNOWN - Impossible to run redis command"
  exit $STATE_UNKNOWN
elif [[ -z "$lag" ]]; then
  echo "UNKNOWN - No replication found"
  exit $STATE_UNKNOWN
else
  output="Replication lag for redis is ${lag}s and offset is ${offset}"
  LC_ALL=C lag=$(printf "%.*f" 0 $lag)

  if [[ $lag -lt 5 && $offset -lt 5 ]]; then
    echo "OK - $output"
    exit $STATE_OK
  elif [[ $lag -lt 10 && $offset -lt 10 ]]; then
    echo "WARNING - $output"
    exit $STATE_WARNING
  else
    echo "CRITICAL - $output"
    exit $STATE_CRITICAL
  fi
fi