# Type definitions for params and previewData
**URL:** https://community.prismic.io/t/type-definitions-for-params-and-previewdata/11717
**Category:** Developing with Prismic
**Created:** [November 16, 2022, 4:29pm UTC](https://community.prismic.io/t/type-definitions-for-params-and-previewdata/11717 "2022-11-16T16:29:38Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@frank.stallone](https://community.prismic.io/u/frank.stallone)
#### Post date: [November 16, 2022, 4:29pm UTC](https://community.prismic.io/t/type-definitions-for-params-and-previewdata/11717/1 "2022-11-16T16:29:38Z")
I am coming back to this code I wrote and not happy with for obvious `any` reasons.
```auto
export async function getStaticProps({ params, previewData }: any) {
const client = createClient({ previewData });
const { uid, lang } = params;
const page = await client.getByUID('components', uid, { lang });
return {
props: {
page,
},
};
}
```
Where can I grab the Typescript definitions for `params` and `previewData`? Not finding this documentation or community members talking about it here.I could use Next.js's `GetStaticProps` but if I do that the destructuring line `const { uid, lang } = params;` has errors presumably because they are from Prismic not Next.js
---
### Author:  [@devteam2](https://community.prismic.io/u/devteam2)
#### Post date: [November 22, 2022, 6:42pm UTC](https://community.prismic.io/t/type-definitions-for-params-and-previewdata/11717/2 "2022-11-22T18:42:36Z")
I also am having a problem with the type definition for the previewData. Maybe someone has an answer for this. Thanks!
---
### Author:  [@Fares](https://community.prismic.io/u/Fares)
#### Post date: [November 24, 2022, 2:44pm UTC](https://community.prismic.io/t/type-definitions-for-params-and-previewdata/11717/5 "2022-11-24T14:44:53Z")
Hi @frank.stallone @devteam2
Thanks for reaching out.
I have reached out to the dev team regarding those TypeScript questions, and here is what we think about it.
- Typing `params`:
We have a new “Next.js: TypeScript” guide that covers what you are asking.
[Use TypeScript with Next.js - Documentation - Prismic](https://prismic.io/docs/typescript-nextjs#typing-page-componentsNote) the use of Next.js’s `GetStaticPropsContext.`
The second code block shows how to use `GetStaticPropsContext` with a typed `params` object.
- Typing `previewData`
Preview data can be anything, depending on the visitor, so it may not be a good idea to type the data manually.
Instead, runtime validation should occur, where you check the object for the property you need before using it.
That being said, `GetStaticPropsContext`’s second type parameter allows someone to define `previewData`’s type.
```auto
type MyPreviewData = {
// Your data here foo: "bar"
}
type PageParams = {
uid: string
}
export function getStaticProps({ params, previewData }: GetStaticPropsContext) {
// ...
}
```
When using `@prismicio/next` and its `enableAutoPreviews()` function, you do not need to type `previewData` manually.
Our recommended setup uses `enableAutoPreviews()`: [Set up Prismic with Next.js - Documentation - Prismic](https://prismic.io/docs/setup-nextjs#configure-prismic)
Please let us know if need any further clarification,
Best
---
### Author:  [@frank.stallone](https://community.prismic.io/u/frank.stallone)
#### Post date: [November 25, 2022, 6:08pm UTC](https://community.prismic.io/t/type-definitions-for-params-and-previewdata/11717/6 "2022-11-25T18:08:44Z")
Thank you for the response and it's great the docs have been updated!! Although `GetStaticPropsContext` works for the `previewData`, take a look at the following error I get for `uid` and `lang`...
`Property 'uid' does not exist on type 'ParsedUrlQuery | undefined'.ts(2339)`
I have not found a way around this. Please advise!
---
### Author:  [@Fares](https://community.prismic.io/u/Fares)
#### Post date: [November 30, 2022, 4:01pm UTC](https://community.prismic.io/t/type-definitions-for-params-and-previewdata/11717/7 "2022-11-30T16:01:45Z")
I'm gathering some information and I will get back to you as soon as possible.
---
### Author:  [@Fares](https://community.prismic.io/u/Fares)
#### Post date: [December 2, 2022, 5:34pm UTC](https://community.prismic.io/t/type-definitions-for-params-and-previewdata/11717/8 "2022-12-02T17:34:06Z")
Hi @frank.stallone ,
**ParsedUrlQuery** should only appear if an explicit type parameter for **params** was not given (note the lack of \<...\> after **GetStaticPropsContext** :
```auto
export async function getStaticProps({ params }:GetStaticPropsContext) {
**params**
// ^ typed as ParsedUrlQuery
}
```
Here’s what it should look like in order to type params:
```auto
type PageParams = {
uid: string
}
```
```auto
export async function getStaticProps({ params }:GetStaticPropsContext) {
params
// ^ typed as PageParams
}
```