index.js

var elasticsearch = require('elasticsearch');

/*
 * Elasticsearch document updater script
 *
 * Given a query that returns the ids of records meeting some sort of criteria,
 * run a bunch of individual update queries to fix the records.
 *
 * Obviously for this to work, the search query has to return fewer and fewer
 * documents as those changes are made.
 */

var client = new elasticsearch.Client({
  host: 'localhost:9200',
  //host: '192.168.6.145:9200' //dev
});

// how many documents to update in one run of the script
var query_size = 100;

client.search({
  "index": "pelias",
  "body": {
    "query": {
      "filtered": {
        "query": {
          "bool": {
            "must": [
              {
                "match": {
                  "parent.region_id": "85682581"
                }
              },
              {
                "match": {
                  "parent.country_a": "SWE"
                }
              }
            ],
            "should": [
              {
                "terms": {
                  "source": [
                    "whosonfirst",
                    "geonames"
                  ]
                }
              }
            ]
          }
        }
      }
    }
  },
  "size": query_size,
  "fields": []
}).then(function(body){
  console.log(body.hits.total + " hits!");

  if (body.hits.total === 0) {
    return;
  }

  var update_doc = {
          "parent": {
            "country_a": [ "DNK"],
            "country": ["Denmark"],
            "country_id": "85633121"
          }
        };

  var bulk_body = body.hits.hits.reduce(function(bulk, hit) {
    var header = {
      update: {
        _index: 'pelias',
        _type: hit['_type'],
        _id: hit['_id']
      }
    };
    var body = {
      doc: update_doc
    };

    return bulk.concat(header, body);
  }, []);

  console.log("updating " + body.hits.hits.length + " documents");
  client.bulk({
    body: bulk_body,
    refresh: true
  },function(err, resp) {
    if (err) {
      console.log("there was an error");
      console.log(err);
      console.log(resp);
    } else {
      console.log("updated!");
    }
  });
});