Add label and icon to nested fields in the doc table (#54199)

* Apply label and icon to nested fields in the doc table

* Include nested fields in the index pattern so we can identify them in the Discover UI

* use color recommended by design

* Fix unit tests

* Update api integration test

* Fix test comment

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>
Co-authored-by: Tim Roes <mail@timroes.de>

src/legacy/ui/public/directives/field_name/field_type_name.ts

@@ -61,6 +61,10 @@ export function getFieldTypeName(type: string) {
       return i18n.translate('common.ui.directives.fieldNameIcons.stringFieldAriaLabel', {
         defaultMessage: 'String field',
       });
+    case 'nested':
+      return i18n.translate('common.ui.directives.fieldNameIcons.nestedFieldAriaLabel', {
+        defaultMessage: 'Nested field',
+      });
     default:
       return i18n.translate('common.ui.directives.fieldNameIcons.unknownFieldAriaLabel', {
         defaultMessage: 'Unknown field',

src/plugins/data/server/index_patterns/fetcher/lib/field_capabilities/field_caps_response.test.js

@@ -37,7 +37,7 @@ describe('index_patterns/field_capabilities/field_caps_response', () => {
     describe('conflicts', () => {
       it('returns a field for each in response, no filtering', () => {
         const fields = readFieldCapsResponse(esResponse);
-        expect(fields).toHaveLength(24);
+        expect(fields).toHaveLength(25);
       });
 
       it(
@@ -68,8 +68,8 @@ describe('index_patterns/field_capabilities/field_caps_response', () => {
         sandbox.spy(shouldReadFieldFromDocValuesNS, 'shouldReadFieldFromDocValues');
         const fields = readFieldCapsResponse(esResponse);
         const conflictCount = fields.filter(f => f.type === 'conflict').length;
-        // +2 is for the object and nested fields which get filtered out of the final return value from readFieldCapsResponse
+        // +1 is for the object field which is filtered out of the final return value from readFieldCapsResponse
-        sinon.assert.callCount(shouldReadFieldFromDocValues, fields.length - conflictCount + 2);
+        sinon.assert.callCount(shouldReadFieldFromDocValues, fields.length - conflictCount + 1);
       });
 
       it('converts es types to kibana types', () => {
@@ -159,10 +159,12 @@ describe('index_patterns/field_capabilities/field_caps_response', () => {
         });
       });
 
-      it('does not include the field actually mapped as nested itself', () => {
+      it('returns the nested parent as not searchable or aggregatable', () => {
         const fields = readFieldCapsResponse(esResponse);
         const child = fields.find(f => f.name === 'nested_object_parent');
-        expect(child).toBeUndefined();
+        expect(child.type).toBe('nested');
+        expect(child.aggregatable).toBe(false);
+        expect(child.searchable).toBe(false);
       });
 
       it('should not confuse object children for multi or nested field children', () => {

src/plugins/data/server/index_patterns/fetcher/lib/field_capabilities/field_caps_response.ts

@@ -195,6 +195,6 @@ export function readFieldCapsResponse(fieldCapsResponse: FieldCapsResponse): Fie
   });
 
   return kibanaFormattedCaps.filter(field => {
-    return !['object', 'nested'].includes(field.type);
+    return !['object'].includes(field.type);
   });
 }

src/plugins/kibana_react/public/field_icon/field_icon.tsx

@@ -36,6 +36,7 @@ interface FieldIconProps {
     | 'number'
     | '_source'
     | 'string'
+    | 'nested'
     | string;
   label?: string;
   size?: IconSize;
@@ -61,6 +62,7 @@ export const typeToEuiIconMap: Partial<Record<string, IconMapEntry>> = {
   number: { icon: 'number', color: colors[0] },
   _source: { icon: 'editorCodeBlock', color: colors[3] },
   string: { icon: 'string', color: colors[4] },
+  nested: { icon: 'nested', color: colors[2] },
 };
 
 /**

test/api_integration/apis/index_patterns/fields_for_wildcard_route/response.js

@@ -71,6 +71,14 @@ export default function({ getService }) {
               name: 'foo',
               readFromDocValues: true,
             },
+            {
+              aggregatable: false,
+              esTypes: ['nested'],
+              name: 'nestedField',
+              readFromDocValues: false,
+              searchable: false,
+              type: 'nested',
+            },
             {
               aggregatable: false,
               esTypes: ['keyword'],
@@ -153,6 +161,14 @@ export default function({ getService }) {
               name: 'foo',
               readFromDocValues: true,
             },
+            {
+              aggregatable: false,
+              esTypes: ['nested'],
+              name: 'nestedField',
+              readFromDocValues: false,
+              searchable: false,
+              type: 'nested',
+            },
             {
               aggregatable: false,
               esTypes: ['keyword'],