Bulk reindexing elasticsearch to another cluster using jq

reindex.sh

#/bin/bash

if [ $# -lt 3 ]
then
  echo "Usage: reindex.sh source_url target_url index [query]"
  echo "Example: reindex.sh http://source.com:9200 http://target.com:9200 products_v1 '{\"query\":{\"range\":{\"mod_date\":{\"from\":\"2015-12-03T20:00:00\"}}}}'"
  exit 1
fi

SOURCE_URL=$1
DESTINATION_URL=$2

index=$3
query=$4

document_type="default-type"

scroll_id=$(curl -s -XPOST $SOURCE_URL'/'$index'/_search?size=50&scroll=1m&search_type=scan' -d "$query" | jq '."_scroll_id"' | tr -d '"')

echo "scroll_id: $scroll_id"

page=1
while true
do
  echo "page: $page"
  page=$((page + 1))
  file=/tmp/$document_type.json
  curl -s $SOURCE_URL'/_search/scroll?scroll=1m' -d "$scroll_id" | jq -c '.hits.hits[] ._source' > $file

  if [[ "$(wc -l $file | awk '{print $1}')" -eq "0" ]]
  then
    echo "finished"
    exit 0
  fi

  cat $file | jq -c '{"index": {"_index": "'$index'", "_type": "'$document_type'", "_id": .id}}, .' | curl -s -XPOST $DESTINATION_URL/_bulk --data-binary @- > /dev/null
done