PublicKeyCredential: isConditionalMediationAvailable() static method

Secure context

The isConditionalMediationAvailable() static method of the PublicKeyCredential interface returns a Promise which resolves to true if conditional mediation is available.

Syntax

PublicKeyCredential.isConditionalMediationAvailable()

Parameters

None.

Return value

A Promise which resolves to a boolean value indicating whether or not conditional mediation is available.

Exceptions

The returned Promise may be rejected with the following values:

• SecurityError DOMException
  • : The RP domain is not valid.

Examples

Before invoking a conditional WebAuthn API call, check if:

• The browser supports the Web Authentication API.
• The browser supports conditional mediation.

// Availability of `window.PublicKeyCredential` means WebAuthn is usable.
if (
  window.PublicKeyCredential &&
  PublicKeyCredential.isConditionalMediationAvailable
) {
  // Check if conditional mediation is available.
  const isCMA = await PublicKeyCredential.isConditionalMediationAvailable();
  if (isCMA) {
    // Call WebAuthn authentication
    const publicKeyCredentialRequestOptions = {
      // Server generated challenge
      challenge: challengeFromServer,
      // The same RP ID as used during registration
      rpId: "example.com",
    };

    const credential = await navigator.credentials.get({
      publicKey: publicKeyCredentialRequestOptions,
      signal: abortController.signal,
      // Specify 'conditional' to activate conditional UI
      mediation: "conditional",
    });
  }
}

Specifications

Browser compatibility