> ## Documentation Index
> Fetch the complete documentation index at: https://algolia.com/llms.txt
> Use this file to discover all available pages before exploring further.

# insights

> Middleware for setting the user token and sending click and conversion events to the Insights API.

```ts Signature theme={"system"}
createInsightsMiddleware({
  insightsClient: null | InsightsClient,
  insightsInitParams?: object,
  onEvent?: (event: InsightsEvent, aa: null | InsightsClient) => void,
});
```

## Import

<CodeGroup>
  ```js Package manager theme={"system"}
  import { createInsightsMiddleware } from "instantsearch.js/es/middlewares";
  ```

  ```js CDN theme={"system"}
  const { createInsightsMiddleware } = instantsearch.middlewares;
  // or directly use instantsearch.middlewares.createInsightsMiddleware()
  ```
</CodeGroup>

## About this widget

<Note>
  Starting from v4.55.0, you can use the [`insights`](/doc/api-reference/widgets/instantsearch/js#param-insights)
  option instead of setting up the Insights middleware yourself.
</Note>

The `createInsightsMiddleware` creates an insights middleware to help you achieve the following:

1. Set the `userToken` for insights purposes (Click Analytics, Personalization, etc.)
2. Automatically send events from built-in widgets (you can turn this off)
3. Lets you send events from your own custom widgets

### Requirements

* [`search-insights`](https://github.com/algolia/search-insights.js) v1.6.2 or later.
* [InstantSearch.js](https://github.com/algolia/instantsearch) v4.8.3 or later.

See also: [Send click and conversion events with InstantSearch.js](/doc/guides/building-search-ui/events/js)

## Examples

```js JavaScript icon=code theme={"system"}
const insightsMiddleware = createInsightsMiddleware({
  insightsClient,
  insightsInitParams,
  onEvent,
});

search.use(insightsMiddleware);
```

## Options

<ParamField body="insightsClient" type="InsightsClient | null">
  The [Insights client](/doc/libraries/search-insights?client=javascript) is used to send events.
  It synchronizes the [user token](/doc/guides/sending-events/concepts/usertoken#exclude-users-who-want-to-opt-out-of-analytics-recommend-and-personalization)
  between search and analytics calls.

  To disable `userToken` synchronization and automatic event sending, set this to `null`.

  <CodeGroup>
    ```html UMD theme={"system"}
    <script>
      /*
        A snippet to include `search-insights`
        You can find it here
        https://github.com/algolia/search-insights.js
      */
    </script>

    <script>
      const insightsMiddleware = instantsearch.middlewares.createInsightsMiddleware({
        insightsClient: window.aa,
      });

      search.use(insightsMiddleware);

      const userToken = // Get the user token (synchronously or asynchronously).

      // The `insights` middleware receives a notification
      // and attaches the `userToken` to search calls onwards.
      window.aa('setUserToken', userToken);
    </script>
    ```

    ```js ESM theme={"system"}
    import aa from "search-insights";
    import { createInsightsMiddleware } from "instantsearch.js/es/middlewares";

    const insightsMiddleware = createInsightsMiddleware({
      insightsClient: aa,
    });

    search.use(insightsMiddleware);

    // Get the user token (synchronously or asynchronously).
    const userToken = /*...*/;

    // The `insights` middleware receives a notification
    // and attaches the `userToken` to search calls onwards.
    aa("setUserToken", userToken);
    ```
  </CodeGroup>
</ParamField>

<ParamField body="insightsInitParams" type="object" post={['since: v4.11.0']}>
  Insights parameters to forward to the Insights client's [`init`](/doc/libraries/search-insights/init) method.

  With `search-insights >= v1.7.0 and < 2.0.0`,
  the Insights client accepts `useCookie` and `userToken` parameters in the [`init`](/doc/libraries/search-insights/init) method.
  You can pass `useCookie: false` to prevent the usage of cookies to store an anonymous `userToken`.
  You can also pass a custom `userToken` while creating `insights` middleware, if you have one.

  With `search-insights >= 2.0.0`, the default value of `useCookie` is `false`.

  <Note>
    You can set an authenticated user token and a user token in `insightsInitParams`.
    Both tokens are passed to the Insights API for sending events.
    If both are set, InstantSearch uses the authenticated user token for search queries.
  </Note>

  <CodeGroup>
    ```js Cookie theme={"system"}
    createInsightsMiddleware({
      insightsInitParams: {
        useCookie: true,
      },
    });
    ```

    ```js Tokens theme={"system"}
    createInsightsMiddleware({
      insightsInitParams: {
        userToken: "user-token",
        authenticatedUserToken: "auth-user-token",
      },
    });
    ```
  </CodeGroup>
</ParamField>

<ParamField body="onEvent" type="(event: InsightsEvent, aa: null | InsightsClient) => void">
  By default, the middleware sends events to Algolia using the provided `insightsClient`.
  You can also control events and send them yourself by implementing an `onEvent` method for the middleware to call instead.
  The method lets you access data, and filter or modify the payload. You can also use it to send events to third-party trackers.

  If you want to use `onEvent` to send events to third-party trackers,
  but don't want to send them to Algolia,
  you can set `insightsClient` to `null`,
  and you don't need the `search-insights` library in your application.

  <Expandable title="event properties">
    <ParamField body="event.insightsMethod" type="string">
      The Insights method, such as, `'viewedObjectIDs'`, `'clickedObjectIDsAfterSearch'`.
      For more information, see the [Insights API reference](/doc/libraries/search-insights).
    </ParamField>

    <ParamField body="event.payload" type="[key: string]: any">
      Event payload.
    </ParamField>

    <ParamField body="event.widgetType" type="string">
      Widget type given by connectors, such as `'ais.refinementList` or `'ais.hits`.
    </ParamField>

    <ParamField body="event.eventType" type="string">
      Event type, such as `'view'`, `'click'`, `'conversion'`, or anything else if you customized it.
    </ParamField>
  </Expandable>

  ```js JavaScript icon=code theme={"system"}
  createInsightsMiddleware({
    insightsClient: window.aa,
    onEvent: (event, aa) => {
      const { insightsMethod, payload, widgetType, eventType } = event;

      // Send the event to Algolia
      if (insightsMethod) {
        aa(insightsMethod, payload);
      }

      // Send the event to a third-party tracker
      if (widgetType === "ais.hits" && eventType === "click") {
        thirdPartyTracker.send("Product Clicked", payload);
      }
    },
  });
  ```
</ParamField>

## Custom events

<ParamField body="Connectors">
  Many of the InstantSearch connectors expose the `sendEvent` method.
  If you use these connectors to create custom widgets, you can leverage the method to send custom events.

  Here's a list of connectors that expose `sendEvent`.

  * `connectAutocomplete`: [`autocomplete`](/doc/api-reference/widgets/autocomplete/js#param-indices)
  * `connectGeoSearch`: [`geoSearch`](/doc/api-reference/widgets/geo-search/js#param-send-event)
  * `connectHierarchicalMenu`: [`hierarchicalMenu`](/doc/api-reference/widgets/hierarchical-menu/js#param-send-event)
  * `connectHits`: [`hits`](/doc/api-reference/widgets/hits/js#param-send-event)
  * `connectInfiniteHits`: [`infiniteHits`](/doc/api-reference/widgets/infinite-hits/js#param-send-event)
  * `connectMenu`: [`menu`](/doc/api-reference/widgets/menu/js#param-send-event) and [`menuSelect`](/doc/api-reference/widgets/menu-select/js#param-send-event) \*
  * `connectNumericMenu`: [`numericMenu`](/doc/api-reference/widgets/numeric-menu/js#param-send-event)
  * `connectRange`: [`rangeInput`](/doc/api-reference/widgets/range-input/js#param-send-event) and [`rangeSlider`](/doc/api-reference/widgets/range-slider/js#param-send-event) \*
  * `connectRatingMenu`: [`ratingMenu`](/doc/api-reference/widgets/rating-menu/js#param-send-event) \*
  * `connectRefinementList`: [`refinementList`](/doc/api-reference/widgets/refinement-list/js#param-send-event)
  * `connectToggleRefinement`: [`toggleRefinement`](/doc/api-reference/widgets/toggle-refinement/js#param-send-event)

  <Note>
    \* The `sendEvent` method provided to `connectNumericMenu`, `connectRange`, and `connectRatingMenu` can't be used to send [clicked filter](/doc/libraries/sdk/v1/methods/clicked-filters) events.
  </Note>

  ```js JavaScript icon=code theme={"system"}
  const renderRefinementList = (renderOptions, isFirstRendering) => {
    const { sendEvent } = renderOptions;

    // `sendEvent` from `connectRefinementList` can send `click` events.
    const clickedFacetValue = "Apple";

    // This sends an event like the following:
    /*
      {
        eventType: 'click',
        insightsMethod: 'clickedFilters',
        payload: {
          eventName: 'Filter Applied',
          filters: ['brand:"Apple"'],
          index: '<your-index-name>',
        },
        widgetType: 'ais.refinementList',
      }
    */
    sendEvent("click", clickedFacetValue);

    // Or, you can send a custom payload
    sendEvent({
      eventType: "click",
      insightsMethod: "clickedFilters",
      payload: {
        eventName: "Filter Applied",
        filters: [`brand:${JSON.stringify(clickedFacetValue)}`],
        index: "<your-index-name>",
      },
      widgetType: "ais.refinementList",
    });
  };

  const customRefinementList = connectRefinementList(renderRefinementList);
  ```
</ParamField>

<ParamField body="Hits">
  The [`hits`](/doc/api-reference/widgets/hits/js) and [`infiniteHits`](/doc/api-reference/widgets/infinite-hits/js)
  widgets provide templates with an exposed `sendEvent` function.

  The `sendEvent(eventType, payload, eventName)` function triggers an event.
  When clicking the button, InstantSearch sends it to Algolia, or forwards it to `onEvent` if provided.

  * `eventType: 'click' | 'conversion'`
  * `payload: Hit`
  * `eventName: string`

  ```js JavaScript icon=code theme={"system"}
  hits({
    // or `infiniteHits`
    // ...
    templates: {
      item: (hit, { html, components, sendEvent }) => {
        return html`
          <div>
            <p>${components.Highlight({ attribute: "title", hit })}</p>
            <button
              type="button"
              onClick=${() => sendEvent("conversion", hit, "Product Added")}
            >
              Add to cart
            <button>
          </div>
        `;
      },
    },
  });
  ```
</ParamField>