expressions indexPattern function (#70315)

src/plugins/data/public/index_patterns/expressions/index.ts

@@ -0,0 +1,20 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+export * from './load_index_pattern';

src/plugins/data/public/index_patterns/expressions/load_index_pattern.test.ts

@@ -0,0 +1,39 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { indexPatternLoad } from './load_index_pattern';
+
+jest.mock('../../services', () => ({
+  getIndexPatterns: () => ({
+    get: (id: string) => ({
+      toSpec: () => ({
+        title: 'value',
+      }),
+    }),
+  }),
+}));
+
+describe('indexPattern expression function', () => {
+  test('returns serialized index pattern', async () => {
+    const indexPatternDefinition = indexPatternLoad();
+    const result = await indexPatternDefinition.fn(null, { id: '1' }, {} as any);
+    expect(result.type).toEqual('index_pattern');
+    expect(result.value.title).toEqual('value');
+  });
+});

src/plugins/data/public/index_patterns/expressions/load_index_pattern.ts

@@ -0,0 +1,62 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { i18n } from '@kbn/i18n';
+import { ExpressionFunctionDefinition } from '../../../../../plugins/expressions/public';
+import { getIndexPatterns } from '../../services';
+import { IndexPatternSpec } from '../../../common/index_patterns';
+
+const name = 'indexPatternLoad';
+
+type Input = null;
+type Output = Promise<{ type: 'index_pattern'; value: IndexPatternSpec }>;
+
+interface Arguments {
+  id: string;
+}
+
+export const indexPatternLoad = (): ExpressionFunctionDefinition<
+  typeof name,
+  Input,
+  Arguments,
+  Output
+> => ({
+  name,
+  type: 'index_pattern',
+  inputTypes: ['null'],
+  help: i18n.translate('data.functions.indexPatternLoad.help', {
+    defaultMessage: 'Loads an index pattern',
+  }),
+  args: {
+    id: {
+      types: ['string'],
+      required: true,
+      help: i18n.translate('data.functions.indexPatternLoad.id.help', {
+        defaultMessage: 'index pattern id to load',
+      }),
+    },
+  },
+  async fn(input, args) {
+    const indexPatterns = getIndexPatterns();
+
+    const indexPattern = await indexPatterns.get(args.id);
+
+    return { type: 'index_pattern', value: indexPattern.toSpec() };
+  },
+});

src/plugins/data/public/plugin.ts

@@ -82,6 +82,7 @@ import {
   ValueClickActionContext,
 } from './actions/value_click_action';
 import { SavedObjectsClientPublicToCommon } from './index_patterns';
+import { indexPatternLoad } from './index_patterns/expressions/load_index_pattern';
 
 declare module '../../ui_actions/public' {
   export interface ActionContextMapping {
@@ -126,6 +127,7 @@ export class DataPublicPlugin implements Plugin<DataPublicPluginSetup, DataPubli
     };
 
     expressions.registerFunction(esaggs);
+    expressions.registerFunction(indexPatternLoad);
 
     const queryService = this.queryService.setup({
       uiSettings: core.uiSettings,