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

## Submitting Feedback

If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:

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  "path": "/optimize/feedback", # the path of the page where the issue is observed
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</AgentInstructions>

# Index Data from a Linked Module

In this guide, you'll learn how to include a linked module's data in a [search index definition](https://docs.medusajs.com/resources/infrastructure-modules/search/index-definitions).

### Prerequisites

- [Medusa v2.21.1+](https://github.com/medusajs/medusa/releases/tag/v2.21.1)

An index isn't limited to the fields of its own `entity`. [Query](https://docs.medusajs.com/learn/fundamentals/query) resolves [module links](https://docs.medusajs.com/learn/fundamentals/module-links), so `graphSeed` and `graphConsume` can select a linked module's fields with the same dotted paths that `query.graph` accepts.

The examples in this section index products along with the brand each product is linked to, using the [custom Brand Module](https://docs.medusajs.com/learn/customization/custom-features/module) and the [product-brand link](https://docs.medusajs.com/learn/customization/extend-features/define-link) from the Medusa documentation.

The product indexes in this guide's snippets are simplified to show one feature at a time. For examples of indexing prices in multiple currencies, option values, categories, and other product data, refer to the [Product Index Examples guide](https://docs.medusajs.com/resources/infrastructure-modules/search/product-index-examples).

## Select and Declare the Linked Fields

To hold a linked module's data in the index:

1. Select the linked fields in `graphSeed` and `graphConsume`, the way you'd select them in `query.graph`. For example, `brand.name`.
2. Declare them in the index's `fields` with `search.object`, mirroring the shape `query.graph` returns.

For example, create the file `src/search/product.ts` with the following content:

```ts title="src/search/product.ts"
import {
  defineSearchIndex,
  graphConsume,
  graphSeed,
  search,
} from "@medusajs/framework/utils"

const fields = [
  "id",
  "title",
  "status",
  "brand.id",
  "brand.name",
]

export const productIndex = defineSearchIndex({
  name: "product",
  entity: "product",
  fields: search.define({
    id: search.keyword().filterable(),
    title: search.text().searchable({ weight: 3 }),
    status: search.keyword().filterable(),
    brand: search.object({
      id: search.keyword().filterable(),
      name: search
        .keyword()
        .searchable()
        .filterable()
        .facetable(),
    }),
  }),
  events: [
    "product.created",
    "product.updated",
    "product.deleted",
  ],
  consume: graphConsume({ fields }),
  seed: graphSeed({ fields }),
})
```

`query.graph` returns a linked brand as a nested object, so an indexed document has the following shape:

```json
{
  "id": "1",
  "title": "Product Title",
  "status": "active",
  "brand": {
    "id": "10",
    "name": "Acme",
  },
}
```

Refer to [Search Index Fields](https://docs.medusajs.com/resources/infrastructure-modules/search/index-definitions/fields) for every field type and modifier.

The [Store Search API route](https://docs.medusajs.com/api/store/search/search-indexes) resolves the index by the `entity` a query names, so the fields you add to your `product` index become available to storefront searches. Refer to [Search Products](https://docs.medusajs.com/resources/infrastructure-modules/search#search-products) for how to query it.

***

## Reference Nested Fields by Their Full Path

The search engine flattens an object field into its leaves, each keyed by its dotted path, such as `brand.name`. Filters, facets, and sorting take that path as a string key.

For example, to filter and facet products by their linked brand's name:

```ts
const { data: products } = await query.search({
  entity: "product",
  fields: ["id", "title", "brand.name"],
  filters: {
    q: "shirt",
    "brand.name": "Acme",
  },
  search_options: {
    facets: ["brand.name"],
  },
})
```

Keep the following in mind when you filter, facet, or sort on nested fields:

- The object itself isn't a field. Only the leaves are indexed, so `brand` is not something you can filter on. A filter on it throws `Unknown filter field "brand"`.
- Put the full path in the filter's key, not in its value. `{ "brand.name": "Acme" }` works, whereas `{ brand: { name: "Acme" } }` throws the same error, since the provider reads a nested object as an operator map.
- A leaf must be declared, and it must carry the modifier for what you're doing with it. Filtering on `brand.name` requires `filterable()` on that leaf, faceting requires `facetable()`, and sorting requires `sortable()`.

***

## Keep the Index Current When Linked Data Changes

Changing a brand doesn't emit a product event, so a product's document keeps the brand name it was indexed with until something re-ingests that product. The same is true when a link is created or removed, which emits no event at all.

You can ensure the index stays current when a brand is updated by:

1. [Emit the brand update event in the workflow updating it](https://docs.medusajs.com/learn/fundamentals/events-and-subscribers/emit-event#emit-event-in-a-workflow).
2. Pass the brand update event to the product index's `events` array so it can trigger the `consume` function and re-ingest the affected products.
3. Implement the `consume` function to handle the brand update event, resolve the affected products, and re-ingest them.

For example, to pass the brand update event to the product index and handle it in the `consume` function:

```ts title="src/search/product.ts"
import {
  defineSearchIndex,
  graphConsume,
  graphSeed,
  search,
} from "@medusajs/framework/utils"

const consumeProducts = graphConsume({ fields })

export const productIndex = defineSearchIndex({
  // ...
  events: [
    "product.created",
    "product.updated",
    "product.deleted",
    "brand.updated",
  ],
  async consume(event, context) {
    if (event.name.startsWith("product.")) {
      return await consumeProducts(event, context)
    }

    const { data: brands } = await context.container
      .query.graph({
        entity: "brand",
        fields: ["products.id"],
        filters: { id: event.data.id },
      })

    const ids = brands[0]?.products?.map(
      (product) => product.id
    ) ?? []

    return await consumeProducts(
      { name: "product.updated", data: { id: ids } },
      context
    )
  },
  seed: graphSeed({ fields }),
})
```

You use `graphConsume` to handle product events. For brand updates, you manually resolve the affected products and re-ingest them as `product.updated` events.

### Re-Ingest a Product After a Link Change

Creating or removing a link doesn't emit an event either, so nothing tells the index that a product's brand changed. To keep the index current, [emit your own event in the workflow that changes the link](https://docs.medusajs.com/learn/fundamentals/events-and-subscribers/emit-event#emit-event-in-a-workflow), then handle it in `consume` as you do the brand update event.

For example, , add the event to the index's `events` array and handle it in `consume`:

```ts title="src/search/product.ts"
export const productIndex = defineSearchIndex({
  // ...
  events: [
    "product.created",
    "product.updated",
    "product.deleted",
    "brand.updated",
    "product-brand.linked",
  ],
  async consume(event, context) {
    // ...

    if (event.name === "product-brand.linked") {
      return await consumeProducts(
        {
          name: "product.updated",
          data: { id: event.data.product_id },
        },
        context
      )
    }

    // ... handle brand.updated
  },
})
```

This example assumes the event carries the product's ID. You re-ingest it as a `product.updated` event, which rebuilds the document with the brand it's now linked to.


---

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