How to format a date to insert in Elasticsearch

Question

I'm coding a Java app to insert data in Elasticsearch 7.5.1. When creating the index the property was set like this:

"datetime":{
   "type":"date"            
}

Now when inserting the date I'm getting this error:

org.elasticsearch.index.mapper.MapperParsingException: failed to parse field [datetime] of type [date] in document with id '195'. Preview of field's value: '2018-11-23 10:38:00'

I'm currently doing it like this:

DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String v = dateFormat.format(date);

And checking a working index I can see it's formatted like this, example: 2019-10-09T11:11:38.879-04:00

What is the mask to create that format?

I recommend you don’t use `SimpleDateFormat` and `Date`. Those classes are poorly designed and long outdated, the former in particular notoriously troublesome. Instead use for example `LocalDateTime` and `DateTimeFormatter`, both from [java.time, the modern Java date and time API](https://docs.oracle.com/javase/tutorial/datetime/). — Ole V.V., Jan 15 '20 at 06:11

ibexit · Accepted Answer · 2020-01-14T23:11:01.197

According to the docs, you can specify multiple date formats for your field "datetime".

The datetime from the error message above, 2018-11-23 10:38:00, needs to be mapped with yyyy-MM-dd HH:mm:ss in order to get indexed.

Please consider setting a timezone or even better use ISO 8601 format as elastic internally stores all dates as UTC. If you don't provide a Timezone, the datetime you are indexing will be assumed as UTC but your application may run in a different Timezone. This can cause trouble ;)

Back to the solution. Define the mapping like this for the datetime field:

PUT my_index
{
  "mappings": {
    "properties": {
      "datetime": {
        "type":   "date",
        "format": "yyyy-MM-dd HH:mm:ss||yyyy-MM-dd'T'HH:mm:ss.SSSZ||epoch_millis"
      }
    }
  }
}

And it will process datetime values like

2018-11-23 10:38:00 (your current format)
2001-07-04T12:08:56.235-0700 (ISO 8601)
1095379198 (unix time)

If you want more background information on date & time handling in java, have a look at this. Old, but gold.

Cheers!

How to format a date to insert in Elasticsearch

1 Answers1