elasticsearch/elasticsearch — pull request #9104 by dadoonet (2014-12-30 16:45:21+00:00)
Title: [Mapper] Add `ignore_null` option to `timestamp`

Related to #9049.

By default, the default value for `timestamp` is `now` which means the date the document was processed by the indexing chain.

You can now reject documents which not provide a `timestamp` value by setting `ignore_null` to false (default to `true`):

```js
{
"tweet" : {
"_timestamp" : {
"enabled" : true,
"ignore_null" : false
}
}
}
```

Closes #8882.