### Question:
RemoteValidatorApiHandler implements ValidatorApiChannel { @Override public void sendSignedAttestation(final Attestation attestation) { final tech.pegasys.teku.api.schema.Attestation schemaAttestation = new tech.pegasys.teku.api.schema.Attestation(attestation); asyncRunner .runAsync(() -> apiClient.sendSignedAttestation(schemaAttestation)) .finish(error -> LOG.error("Failed to send signed attestation", error)); ; } RemoteValidatorApiHandler(final ServiceConfig config, final AsyncRunner asyncRunner); @VisibleForTesting  RemoteValidatorApiHandler(
      final ValidatorRestApiClient apiClient, final AsyncRunner asyncRunner); @Override SafeFuture<Optional<ForkInfo>> getForkInfo(); @Override SafeFuture<Optional<UInt64>> getGenesisTime(); @Override SafeFuture<Optional<List<ValidatorDuties>>> getDuties(
      final UInt64 epoch, final Collection<BLSPublicKey> publicKeys); @Override SafeFuture<Optional<List<AttesterDuties>>> getAttestationDuties(
      final UInt64 epoch, final Collection<Integer> validatorIndexes); @Override SafeFuture<Optional<List<ProposerDuties>>> getProposerDuties(final UInt64 epoch); @Override SafeFuture<Optional<Attestation>> createUnsignedAttestation(
      final UInt64 slot, final int committeeIndex); @Override void sendSignedAttestation(final Attestation attestation); @Override void sendSignedAttestation(
      final Attestation attestation, final Optional<Integer> validatorIndex); @Override SafeFuture<Optional<BeaconBlock>> createUnsignedBlock(
      final UInt64 slot, final BLSSignature randaoReveal, final Optional<Bytes32> graffiti); @Override void sendSignedBlock(final SignedBeaconBlock block); @Override SafeFuture<Optional<Attestation>> createAggregate(final Bytes32 attestationHashTreeRoot); @Override void sendAggregateAndProof(final SignedAggregateAndProof aggregateAndProof); @Override void subscribeToBeaconCommitteeForAggregation(
      final int committeeIndex, final UInt64 aggregationSlot); @Override void subscribeToPersistentSubnets(final Set<SubnetSubscription> subnetSubscriptions);  }### Answer:
@Test public void sendSignedAttestation_InvokeApiWithCorrectRequest() { final Attestation attestation = dataStructureUtil.randomAttestation(); final tech.pegasys.teku.api.schema.Attestation schemaAttestation = new tech.pegasys.teku.api.schema.Attestation(attestation); ArgumentCaptor<tech.pegasys.teku.api.schema.Attestation> argumentCaptor = ArgumentCaptor.forClass(tech.pegasys.teku.api.schema.Attestation.class); apiHandler.sendSignedAttestation(attestation); asyncRunner.executeQueuedActions(); verify(apiClient).sendSignedAttestation(argumentCaptor.capture()); assertThat(argumentCaptor.getValue()).usingRecursiveComparison().isEqualTo(schemaAttestation); }
@Test public void sendSignedAttestation_IgnoresValidatorIndexParameter_AndInvokeApi() { final Attestation attestation = dataStructureUtil.randomAttestation(); final tech.pegasys.teku.api.schema.Attestation schemaAttestation = new tech.pegasys.teku.api.schema.Attestation(attestation); ArgumentCaptor<tech.pegasys.teku.api.schema.Attestation> argumentCaptor = ArgumentCaptor.forClass(tech.pegasys.teku.api.schema.Attestation.class); apiHandler.sendSignedAttestation(attestation, Optional.of(1)); asyncRunner.executeQueuedActions(); verify(apiClient).sendSignedAttestation(argumentCaptor.capture()); assertThat(argumentCaptor.getValue()).usingRecursiveComparison().isEqualTo(schemaAttestation); }