[Discover][Main] Introduce dataType text for enable rendering for text based query languages

[kertal]

Discover currently is optimized for handling searches of documents in Elasticsearch. Due to our upcoming support of text based query languages we need to make our interface configureable to handle aggregated and similar data. To start a MVP to allowing displaying the results of a SQL query we should make Discover configureable.

Generally we are using Observable to connect data state changes with ui state changes. This channel should be used to let the UI know which kind of data is to be expected. We should extend our current base message with recordRawType indicating which kind of data records are expected:

export enum RecordRawType {
  /**
   * Documents returned from Elasticsearch, nested structure
   */
  DOCUMENT = 'document',
  /**
   * Data returned e.g. SQL queries, flat structure
   * */
  PLAIN = 'plain',
}

export interface DataMsg {
  fetchStatus: FetchStatus;
  error?: Error;
  recordRawType?: RecordRawType;
}

This way all messages sent to the UI can be used to read this state.

Depending on recordRawType , Discover's main interface should provide different features

Generally

feature	document	plain
add filters	✅	-
field statistics	✅	-
histogram	✅	-
number of hits	✅	-
Surrounding documents	✅	-
Single document	✅	-

Toolbar

feature	document	plain
Alerts	✅	-
Share	✅	-

Sidebar

Currently sidebar is displaying documents of the dataView, when using SQL it should show the fields of the SQL result

feature	document	plain
add filters	✅	-
filter fields	✅	-
field popover	✅	- later on
popular fields	✅	-
add field	✅	-

Also don't show field type icons with plain data. We could just partly match those with data view field, so the MVP approach is: don's show them for now.

Document explorer

When using text based languages no time field should be prepended

feature	document	plain
Doc expansion	✅	-
Sorting	✅	-
Document selection	✅	✅ ... it would work, so why not

Classic table should not be supported for this effort, there should be info panel to inform the user. Generally it's recommendable to configure e.h. the availability of filter functionality by providing or not providing the function depending on recordRawType ... no filter functionality when plain data records are used. With this way we can prevent adding new parameters to components.

POC: #134984
Storybook PR, useful for development of UI: #134716

[elasticmachine]

Pinging @elastic/kibana-data-discovery (Team:DataDiscovery)

[stratoula]

@kertal I think we can close this, right?

[kertal]

sure, thx