Description:
{description}
Is done:
{isDone ? "Yes" : "No"}
)
}
export default MainPage
```
Notice how you don't need to annotate the Query's return value type. Wasp automatically infers the from the Query's backend implementation. This is **full-stack type safety**: the types on the client always match the types on the server.
For a detailed specification of the `useQuery` hook, check the [API Reference](#api-reference).
#### Error Handling
For security reasons, all exceptions thrown in the Query's NodeJS implementation are sent to the client as responses with the HTTP status code `500`, with all other details removed. Hiding error details by default helps against accidentally leaking possibly sensitive information over the network.
If you do want to pass additional error information to the client, you can construct and throw an appropriate `HttpError` in your implementation:
```ts title="src/queries.ts"
import { type GetAllTasks } from "wasp/server/operations"
import { HttpError } from "wasp/server"
export const getAllTasks: GetAllTasks = async (args, context) => {
throw new HttpError(
403, // status code
"You can't do this!", // message
{ foo: "bar" } // data
)
}
```
If the status code is `4xx`, the client will receive a response object with the corresponding `message` and `data` fields, and it will rethrow the error (including these fields). To prevent information leakage, the server won't forward these fields for any other HTTP status codes.
#### Using Entities in Queries
In most cases, resources used in Queries will be [Entities](https://wasp.sh/docs/features/data/entities). To use an Entity in your Query, add it to the `query` spec in Wasp:
```ts title="main.wasp.ts"
import { app, query } from "@wasp.sh/spec"
import { getAllTasks, getFilteredTasks } from "./src/queries" with { type: "ref" }
export default app({
// ...
spec: [
query(getAllTasks, { entities: ["Task"] }),
query(getFilteredTasks, { entities: ["Task"] }),
],
})
```
Wasp will inject the specified Entity into the Query's `context` argument, giving you access to the Entity's Prisma API:
```ts title="src/queries.ts"
import { type Task } from "wasp/entities"
import { type GetAllTasks, type GetFilteredTasks } from "wasp/server/operations"
export const getAllTasks: GetAllTasks