Shell script for mongoexport with query

mongoexport_with_query.sh

#!/bin/sh

#########################################################
# usage
#do_mongoexport '2015-04-01' '2015-04-02' 'hoge'
#########################################################

get_millis()
{
  if [ $# != 1 ]; then
    echo $#
    echo "ERROR: Too few arguments." 1>&2
    return 1
  fi

  utc_time=$(date -d $1 -u)
  time_secs=$(date +"%s" -d "$utc_time")
  time_millis=`expr $time_secs \* 1000`
  echo $time_millis

  return 0
}

do_mongoexport()
{
  if [ $# != 3 ]; then
    echo $#
    echo "ERROR: Too few arguments." 1>&2
    return 1
  fi

  database_name="database_name"
  collection_name="collection_name"
  #out_dir=/mnt/mongoexport/working/
  #log_dir=/mnt/mongoexport/working/log/
  out_dir=./
  log_dir=./
  
  start_day=$1
  end_day=$2
  #action_name=$3
  #name=$4
  name=$3

  end_millis=`get_millis $end_day`
  start_millis=`get_millis $start_day`


  echo "do mongoexport for gte $start_day lt $end_day with name $name"

  log_filename="mongoexport_${name}_gte_${start_day}_lt_${end_day}.log"
  out_filename="mongoexport_${name}_gte_${start_day}_lt_${end_day}.json"
  out_path="${out_dir}${out_filename}"
  log_path="${log_dir}${log_filename}"
  query="{time:{\$gte:new Date(${start_millis}),\$lt:new Date(${end_millis})},name:\"${name}\"}"

  nohup mongoexport -d ${database_name} -c ${collection_name} -q "${query}" -o ${out_path} > ${log_path} &

  pid=$! # PID of the most recent background command
  echo "PID is $pid"

}