[Timelion] Communicate the index pattern to the dashboard

Closes elastic#86418

.eslintignore

@@ -22,7 +22,7 @@ snapshots.js
 /src/core/lib/kbn_internal_native_observable
 /src/legacy/plugin_discovery/plugin_pack/__tests__/fixtures/plugins/broken
 /src/plugins/data/common/es_query/kuery/ast/_generated_/**
-/src/plugins/vis_type_timelion/public/_generated_/**
+/src/plugins/vis_type_timelion/common/_generated_/**
 /x-pack/legacy/plugins/**/__tests__/fixtures/**
 /x-pack/plugins/apm/e2e/tmp/*
 /x-pack/plugins/canvas/canvas_plugin

src/plugins/vis_type_timelion/common/types.ts

@@ -33,3 +33,19 @@ export interface ITimelionFunction {
     [key: string]: TimelionFunctionArgs[];
   };
 }
+
+export interface TimelionExpressionNamedArgument {
+  function: string;
+  type: 'namedArg';
+  location: {
+    min: number;
+    max: number;
+  };
+  name: string;
+  text: string;
+  value: {
+    type: string;
+    value: string;
+    text: string;
+  };
+}

src/plugins/vis_type_timelion/public/components/timelion_expression_input_helpers.ts

@@ -13,7 +13,7 @@ import { monaco } from '@kbn/monaco';
 import { Parser } from 'pegjs';
 
 // @ts-ignore
-import { parse } from '../_generated_/chain';
+import { parse } from '../../common/_generated_/chain';
 
 import { ArgValueSuggestions, FunctionArg, Location } from '../helpers/arg_value_suggestions';
 import { ITimelionFunction, TimelionFunctionArgs } from '../../common/types';

src/plugins/vis_type_timelion/public/timelion_vis_type.tsx

@@ -13,8 +13,13 @@ import { DefaultEditorSize } from '../../vis_default_editor/public';
 import { TimelionOptionsProps } from './timelion_options';
 import { TimelionVisDependencies } from './plugin';
 import { toExpressionAst } from './to_ast';
+import { getIndexPatterns } from './helpers/plugin_services';
 
-import { VIS_EVENT_TO_TRIGGER } from '../../visualizations/public';
+// @ts-ignore
+import { parse } from '../common/_generated_/chain';
+
+import { VIS_EVENT_TO_TRIGGER, VisParams } from '../../visualizations/public';
+import { TimelionExpressionNamedArgument } from '../common/types';
 
 const TimelionOptions = lazy(() => import('./timelion_options'));
 
@@ -47,6 +52,19 @@ export function getTimelionVisDefinition(dependencies: TimelionVisDependencies)
     getSupportedTriggers: () => {
       return [VIS_EVENT_TO_TRIGGER.applyFilter];
     },
+    getUsedIndexPattern: (params: VisParams) => {
+      try {
+        const args: TimelionExpressionNamedArgument[] = parse(params.expression)?.args ?? [];
+        const indexArg = args.find((arg) => arg.function === 'es' && arg.name === 'index');
+
+        if (indexArg?.value.text) {
+          return getIndexPatterns().find(indexArg?.value.text);
+        }
+      } catch {
+        // timelion expression is invalid
+      }
+      return [];
+    },
     options: {
       showIndexSelection: false,
       showQueryBar: false,

src/plugins/vis_type_timelion/server/handlers/lib/parse_sheet.js

@@ -7,17 +7,12 @@
  */
 
 import { i18n } from '@kbn/i18n';
-import fs from 'fs';
-import path from 'path';
-import _ from 'lodash';
-const grammar = fs.readFileSync(path.resolve(__dirname, '../../../common/chain.peg'), 'utf8');
-import PEG from 'pegjs';
-const Parser = PEG.generate(grammar);
+import { parse } from '../../../common/_generated_/chain';
 
 export default function parseSheet(sheet) {
-  return _.map(sheet, function (plot) {
+  return sheet.map(function (plot) {
     try {
-      return Parser.parse(plot).tree;
+      return parse(plot).tree;
     } catch (e) {
       if (e.expected) {
         throw new Error(

tasks/config/peg.js

@@ -15,7 +15,7 @@ module.exports = {
     },
   },
   timelion_chain: {
-    src: 'src/plugins/vis_type_timelion/public/chain.peg',
-    dest: 'src/plugins/vis_type_timelion/public/_generated_/chain.js',
+    src: 'src/plugins/vis_type_timelion/common/chain.peg',
+    dest: 'src/plugins/vis_type_timelion/common/_generated_/chain.js',
   },
 };