content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements. See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License. You may obtain a copy of the License at
   *
   *    http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.apache.kafka.common.security.oauthbearer;
  
  import org.apache.kafka.common.security.oauthbearer.internals.secured.CloseableVerificationKeyResolver;
  import org.apache.kafka.common.utils.Utils;
  
  import org.jose4j.keys.resolvers.VerificationKeyResolver;
  
  import java.io.IOException;
  import java.util.List;
  import java.util.Map;
  import java.util.Optional;
  
  import javax.security.auth.login.AppConfigurationEntry;
  
  /**
   * This {@link JwtValidator} uses the delegation approach, instantiating and delegating calls to a
   * more concrete implementation. The underlying implementation is determined by the presence/absence
   * of the {@link VerificationKeyResolver}: if it's present, a {@link BrokerJwtValidator} is
   * created, otherwise a {@link ClientJwtValidator} is created.
   */
  public class DefaultJwtValidator implements JwtValidator {
  
      private final Optional<CloseableVerificationKeyResolver> verificationKeyResolver;
  
      private JwtValidator delegate;
  
      public DefaultJwtValidator() {
          this.verificationKeyResolver = Optional.empty();
      }
  
      public DefaultJwtValidator(CloseableVerificationKeyResolver verificationKeyResolver) {
          this.verificationKeyResolver = Optional.of(verificationKeyResolver);
      }
  
      @Override
      public void configure(Map<String, ?> configs, String saslMechanism, List<AppConfigurationEntry> jaasConfigEntries) {
          if (verificationKeyResolver.isPresent()) {
              delegate = new BrokerJwtValidator(verificationKeyResolver.get());
          } else {
              delegate = new ClientJwtValidator();
          }
  
          delegate.configure(configs, saslMechanism, jaasConfigEntries);
      }
  
      @Override
      public OAuthBearerToken validate(String accessToken) throws JwtValidatorException {
          if (delegate == null)
              throw new IllegalStateException("JWT validator delegate is null; please call configure() first");
  
          return delegate.validate(accessToken);
      }
  
      @Override
      public void close() throws IOException {
          Utils.closeQuietly(delegate, "JWT validator delegate");
      }
  
      JwtValidator delegate() {
          return delegate;
      }
  }
  