> For the complete documentation index, see [llms.txt](https://docs.hello-lisa.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.hello-lisa.com/developers/guides/player-communication/message-api-reference/products/products-hydrate.md). # Products — Hydrate The host app or environment sends a **Hydrate** message to give the LiSA Player current price and availability for products the player already knows about. Send it in reply to a Products — Request Hydration message. The player merges what you send onto the product data the show was authored with, and re-renders any product already on screen. {% hint style="warning" %} Await the App — Listen message before sending. Messages sent earlier may not reach the player. {% endhint %} ### Properties Along with all standard [Message properties](/developers/guides/player-communication/message-api-reference.md#properties), a **Hydrate** message includes the following additional properties:

Name Type Description

Name	Type	Description
`messageType`	`Literal` Required.	`lsc:products:hydrate`
`products`	`Array<HydratedProduct>` Required.	The refreshed products. References the player does not recognize are ignored, and products you leave out keep their authored values — so it is safe to answer with a partial set, or with more products than were asked for. Refer to `HydratedProduct` for detailed information.

messageType

Literal

Required.

lsc:products:hydrate

products

Array<HydratedProduct>

Required.

The refreshed products.

References the player does not recognize are ignored, and products you leave out keep their authored values — so it is safe to answer with a partial set, or with more products than were asked for.

Refer to HydratedProduct for detailed information.

### Merge rules Two rules govern how the player applies what you send. Both exist so that a partial answer is always safe. 1. **Anything you omit keeps its authored value.** A message carrying only `hasStock` will never blank out a title, image, brand or variant. You never have to reconstruct the full product. 2. **Supplying `price` replaces both `price` and `salePrice`.** This is how a product coming off sale is expressed: send the price object without a `salePrice`. If you want to leave pricing untouched, omit `price` entirely. *** ### Type Definition ```typescript interface ProductsHydrateMessage extends Omit { messageType: 'lsc:products:hydrate'; products: Array; recipient: 'LiSA'; } ``` #### **HydratedProduct** Fresh state for one product. Only the attributes that go stale are carried.

Name	Type	Description
`hasStock`	`Boolean` Optional.	Whether the product can currently be bought. The player uses this to render its sold-out state and to enable or disable the add-to-cart call-to-action.
`price`	`HydratedProductPrice` Optional.	The current pricing. Supplying it replaces both `price` and `salePrice`. Refer to `HydratedProductPrice` for detailed information.
`reference`	`String` Required.	The merchant's own product identifier, as supplied to LiSA when the product was created. This is the key the player matches on.
`variants`	`Array<HydratedProductVariant>` Optional.	Per-variant state, for products sold in sizes, colors or other variations. Variants you leave out keep their authored values.

#### **HydratedProductVariant**

Name Type Description

Name	Type	Description
`hasStock`	`Boolean` Optional.	Whether this variant can currently be bought.
`price`	`HydratedProductPrice` Optional.	Pricing for this variant, when it differs from the product's.
`reference`	`String` Required.	The merchant's own variant identifier.

hasStock

Boolean

Optional.

Whether this variant can currently be bought.

price

HydratedProductPrice

Optional.

Pricing for this variant, when it differs from the product's.

reference

String

Required.

The merchant's own variant identifier.

#### **HydratedProductPrice**

Name	Type	Description
`currencyCode`	`String` Required.	The ISO 4217 currency code, for example `EUR`.
`currencySymbol`	`String` Optional.	The symbol to render, for example `€`. When omitted, the player keeps the symbol the product was authored with, and falls back to `currencyCode` if the product had no price at all.
`price`	`Number` Required.	The undiscounted price.
`salePrice`	`Number` Optional.	The discounted price, when the product is on sale. Omit it to express that the product is no longer on sale.

```typescript interface HydratedProduct { hasStock?: boolean; price?: HydratedProductPrice; reference: string; variants?: Array; } interface HydratedProductVariant { hasStock?: boolean; price?: HydratedProductPrice; reference: string; } interface HydratedProductPrice { currencyCode: string; currencySymbol?: string; price: number; salePrice?: number; } ``` ### Example A product on sale with one sold-out variant, and a second product that sold out entirely: ```json { "messageType": "lsc:products:hydrate", "recipient": "LiSA", "sender": "my-shop", "messageId": "b8c9d0e1-f2a3-4b4c-8d5e-7f8091a2b3c4", "products": [ { "reference": "SKU-1234", "hasStock": true, "price": { "currencyCode": "EUR", "currencySymbol": "€", "price": 69.9, "salePrice": 49.9 }, "variants": [ { "reference": "SKU-1234-S", "hasStock": false }, { "reference": "SKU-1234-M", "hasStock": true } ] }, { "reference": "SKU-5678", "hasStock": false } ] } ```