message: update explore-backend readme
diff: # explore-backend
  -Welcome to the explore-backend backend plugin!
  -
  -_This plugin was created through the Backstage CLI_
  +The `explore-backend` plugin provides a backend service for the Explore plugin.
  +This allows your organizations tools to be surfaced in the Explore plugin
  +through an API. It also provides a search collator to make it possible to search
  +for these tools.
  ## Getting started
  @@ -13,36 +14,6 @@ _This plugin was created through the Backstage CLI_
  yarn add --cwd packages/backend @backstage/plugin-explore-backend
  ```
  -### Create a ToolProvider
  -
  -Create a `ToolProvider` to provide `ExploreTool` objects.
  -
  -```ts
  -import {
  - GetExploreToolsRequest,
  - GetExploreToolsResponse,
  -} from '@backstage/plugin-explore-common';
  -
  -export async function getExploreTools(
  - request: GetExploreToolsRequest,
  -): Promise<GetExploreToolsResponse> {
  - const { filter } = request ?? {};
  -
  - // Get tool data from a file or some other source
  - const toolData = getToolData();
  -
  - // Populate ExploreTool[] objects & use filter to filter them
  - const tools = [...toolData].filter(filterToolPredicate);
  -
  - return {
  - tools,
  - };
  -}
  -```
  -
  -**NOTE: You can see the `plugins/explore-backend/src/example/getExampleTools.ts`
  -as a simple hardcoded example.**
  -
  ### Adding the plugin to your `packages/backend`
  You'll need to add the plugin to the router in your `backend` package. You can
  @@ -51,20 +22,18 @@ do this by creating a file called `packages/backend/src/plugins/explore.ts`
  ```ts
  import {
  createRouter,
  - getExampleTools,
  + StaticExploreToolProvider,
  } from '@backstage/plugin-explore-backend';
  import { Router } from 'express';
  import { PluginEnvironment } from '../types';
  -import { getExploreTools } from '../data/explore';
  +import { exploreTools } from '../path/to/your/exploreTools';
  export default async function createPlugin(
  env: PluginEnvironment,
  ): Promise<Router> {
  return await createRouter({
  logger: env.logger,
  - toolProvider: {
  - getTools: getExploreTools,
  - },
  + toolProvider: StaticExploreToolProvider.fromData(exploreTools),
  });
  }
  ```
  @@ -88,6 +57,29 @@ async function main() {
  apiRouter.use(notFoundHandler());
  ```
  +### Wire up Search Indexing
  +
  +To index explore tools you will need to register the search collator in the
  +`packages/backend/src/plugins/search.ts` file.
  +
  +```diff
  ++import { ToolDocumentCollatorFactory } from '@backstage/plugin-explore-backend';
  +
  +async function createSearchEngine(
  + env: PluginEnvironment,
  +): Promise<SearchEngine> {
  + ...
  ++ indexBuilder.addCollator({
  ++ schedule,
  ++ factory: ToolDocumentCollatorFactory.fromConfig(env.config, {
  ++ discovery: env.discovery,
  ++ logger: env.logger,
  ++ }),
  ++ });
  + ...
  +}
  +```
  +
  ### Wire up the Frontend
  See [the explore plugin README](../explore/README.md) for more information.
  