Capturing Mutation Side-Effects
How to deal with side-effects
If you have an endpoint that updates many resources on your server, there is a straightforward mechanism to get all those updates to your client in one request.
By defining a custom Endpoint method on your resource,
you'll be able to use custom response endpoints that still
updated rest-hooks
' normalized cache.
Example:
You're running a crypto trading platform called dogebase
. Every time
a user creates a trade, you need to update some balance information
in their accounts object. So upon POST
ing to the /trade/
endpoint,
you nest both the updated accounts object along with the trade you just
created.
POST /trade/
{
"trade": {
"id": 2893232,
"user": 1,
"amount": "50.2335324",
"coin": "doge",
"created_at": ""
},
"account": {
"id": 899,
"user": 1,
"balance": "1337.00",
"coin_value": "3.50"
}
}
To handle this, we just need to update the schema
to include the custom
endpoint.
TradeResource.ts
import { Resource } from '@rest-hooks/rest';
class TradeResource extends Resource {
// ...
static create<T extends typeof Resource>(this: T) {
return super.create().extend({
schema: {
trade: this,
account: AccountResource,
},
});
}
}
Now if when we use the create() Endpoint generator method,
we will be happy knowing both the trade and account information will
be updated in the cache after the POST
request is complete.
CreateTrade.tsx
export default function CreateTrade() {
const create = useFetcher(TradeResource.create());
//...
}
Note:
Feel free to create completely new Endpoint methods for any custom endpoints you have. This endpoint tells
rest-hooks
how to process any request.