Callers contracts

Callers contracts are contracts already available that can be used to verify attestations on-chain. Each callers will use the Verifier Contract to verify the given attestation and handle the result.

The interface ICaller provide the call entrypoint that can be used to verify an attestation on-chain:

interface ICaller {
  call(attestation: Attestation, verifierAddress: PublicKey): void;
}

Implementation

A main Caller contract is provided and can be extended as needed:

export class Caller extends SmartContract implements ICaller {
  @method call(attestation: Attestation, verifierAddress: PublicKey): void {
    const verifier = new Verifier(verifierAddress);
    const isVerified: Bool = verifier.verify(attestation);
    isVerified.assertTrue();
  }
}

EventCaller

This caller will emit a verifier event when the attestation is verified:

export class EventCaller extends SmartContract implements Caller {
  events = {
    verified: Field,
  };
 
  @method call(attestation: Attestation, verifierAddress: PublicKey) {
    const verifier = new Verifier(verifierAddress);
    const isVerified: Bool = verifier.verify(attestation);
    isVerified.assertTrue("Attestation is not verified.");
 
    this.emitEvent("verified", attestation.hash());
  }
}

Verifier Contract User guide