fix: TypeError: Cannot read properties of undefined (reading 'prototype')

[anishjneoito]

I'm getting the following error after building the app. I'm getting only when i pass query param.
/api/role is working fine. But /api/role?type=1 is throwing below error

" TypeError: Cannot read properties of undefined (reading 'prototype') at ActionParameterHandler.normalizeParamValue)

My code is below. I've emitDecoratorMetadata": true in tsconfig compilerOptions as well.
@Get('/role')
async getRole(@QueryParams() query: any) {
console.log(query.type)
}
Did I miss anything?

[spicemc]

I think instead of using the type any it should be something like:
async getRole(@QueryParams() query: RolesQuery) {

Create a class RolesQuery.

A good example in the documentation is the class GetUsersQuery: QueryParams Example

[thebinij]

// ActivityController.ts
...

@Get("/activities")
    public async getPaginated(
      @CurrentUser({ required: true }) uid: string,
      @QueryParams() query: ActivityParams
...

// ActivityModel.ts

export class ActivityParams{
  @IsPositive()
  limit:number;

  @IsPositive()
  startAt:number
}

I am also getting same error even after following the docs.
TypeError: Cannot read properties of undefined (reading 'prototype')

Can anyone help ?

[attilaorosz]

It’s a bit hard to diagnose without the full context. Did you import reflect-metadata? Are you using koa or express?

[jrthib]

Adding import "reflect-metadata"; at the top of your controller seems to fix this. I was experiencing the same issue. Was consistently reproducible when using @QueryParams(). So you can either switch to @QueryParam as a workaround, which doesn't throw this error, or you can import reflect-metadata at the top of your controller file and it'll be fixed.