---
title: "init(userHandle:relyingParty:signature:clientDataHash:authenticatorData:credentialID:extensionOutput:)"
framework: authenticationservices
role: symbol
role_heading: Initializer
path: "authenticationservices/aspasskeyassertioncredential/init(userhandle:relyingparty:signature:clientdatahash:authenticatordata:credentialid:extensionoutput:)"
---

# init(userHandle:relyingParty:signature:clientDataHash:authenticatorData:credentialID:extensionOutput:)

Initializes a passkey assertion credential object, optionally specifying an extension output.

## Declaration

```swift
convenience init(userHandle: Data, relyingParty: String, signature: Data, clientDataHash: Data, authenticatorData: Data, credentialID: Data, extensionOutput: ASPasskeyAssertionCredentialExtensionOutput?)
```

## Parameters

- `userHandle`: The user handle of the passkey.
- `relyingParty`: The relying party associated with the passkey.
- `signature`: The cryptographic signature of the credential.
- `clientDataHash`: A hash of the client data for the credential.
- `authenticatorData`: The authenticator data of the app that creates the credential.
- `credentialID`: The identifier for the credential.
- `extensionOutput`: An output from WebAuthn extensions.

## See Also

### Creating a passkey assertion credential

- [init(userHandle:relyingParty:signature:clientDataHash:authenticatorData:credentialID:)](authenticationservices/aspasskeyassertioncredential/init(userhandle:relyingparty:signature:clientdatahash:authenticatordata:credentialid:).md)