Index Template editor should support mappings types

[cjcenizal]

In 7.5, if you create an index template that uses a type in the mappings, you'll get an error. Here's an example of mappings with a type:

 {
    "mytype": {
      "properties": {
        "host_name": {
          "type": "keyword"
        },
        "otherfield": {
          "type":"keyword"
        }
      }
    }
  }

Here's the resulting error:

The solution to this is to detect when types are being used and add the include_type_name query parameter to the underlying ES API request. For example:

PUT _template/test2?include_type_name
{
  "index_patterns": [
    "test*"
  ],
  "settings": {
    "number_of_shards": 1
  },
  "mappings": {
    "mytype": {
      "properties": {
        "host_name": {
          "type": "keyword"
        },
        "otherfield": {
          "type":"keyword"
        }
      }
    }
  }
}

Response:

#! Deprecation: [types removal] Specifying include_type_name in put index template requests is deprecated. The parameter will be removed in the next major version.
{
  "acknowledged" : true
}

[elasticmachine]

Pinging @elastic/es-ui (Team:Elasticsearch UI)

[cjcenizal]

Note that this change should only target 7.x, since the include_type_name query param has been removed in 8.0.

[cjcenizal]

After investigation, I think the bug is more severe than I originally outlined in the issue description. We'll need to fix this with the following:

1. Load index templates with include_type_name.
2. If the index template has a custom type or if the user specifies one manually, show a warning callout with a link to the types removal docs. Note that we're just adding the callout above the JSON editor. We're not hiding or removing any functionality.
3. When the index template is saved, check if there is a custom type defined and set include_type_name if there is a custom type defined.

This will preserve an existing custom type and allow the user to specify a custom type, while notifying the user of the types deprecation.

To help users protect themselves against this in 7.4 and 7.5 we should add a warning banner to the docs for these versions, which outlines the problem and steps to avoid it (https://www.elastic.co/guide/en/kibana/current/managing-indices.html#manage-index-templates).

[cjcenizal]

Fixed by #55804

[sebelga]

@cjcenizal Do you know why Github doesn't close automatically the issue although the PR description says "Fix #xxx" ?

Maybe that line should be the last of the PR description for Github to close the related issue?

[cjcenizal]

Not sure, it should still work per the docs.

Maybe that line should be the last of the PR description for Github to close the related issue?

I don't think the position of the line matters based on the above link.

[sebelga]

It is strange. I realized that since a few weeks we had to manually close the issue behind the PR... I see in the doc that it is Fixes and not Fix. I'll use that word from now on 😊