---
title: "validateImpression(parameters:publicKey:)"
framework: storekittest
role: symbol
role_heading: Instance Method
path: "storekittest/skadtestsession/validateimpression(parameters:publickey:)"
---

# validateImpression(parameters:publicKey:)

Validates an impression for a StoreKit-rendered ad.

## Declaration

```swift
func validateImpression(parameters: [String : Any], publicKey: String) throws
```

## Parameters

- `parameters`: A dictionary containing version-specific key values that associate an app installation with an ad campaign for StoreKit-rendered ads. See doc://com.apple.documentation/documentation/StoreKit/ad-network-install-validation-keys for the list of required keys.
- `publicKey`: The public key of the elliptic curve cryptographic key pair you used to generate the signature for the ad impression.

## Discussion

Discussion The cryptographic key pair you use for testing may be a different key pair than you use in production. For testing, use keys from the same key pair when you sign the ad impression and when you call validateImpression(parameters:publicKey:). For more information about signing ad impressions, see Signing and providing ads.

## See Also

### Validating impressions

- [validate(_:publicKey:)](storekittest/skadtestsession/validate(_:publickey:).md)
- [validateWebAdImpressionPayload(_:publicKey:)](storekittest/skadtestsession/validatewebadimpressionpayload(_:publickey:).md)