package com.atlassian.asap.service.core.service;
   
   import com.atlassian.asap.core.client.http.AuthorizationHeaderGeneratorImpl;
   import com.atlassian.asap.core.keys.KeyProvider;
   import com.atlassian.asap.core.keys.privatekey.NullKeyProvider;
   import com.atlassian.asap.core.keys.privatekey.PrivateKeyProviderFactory;
   import com.atlassian.asap.nimbus.serializer.NimbusJwtSerializer;
   import com.atlassian.asap.service.core.spi.AsapConfiguration;
   
  import java.net.URI;
  import java.security.PrivateKey;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * An authorization header generator that is suitable for use as a globally configured component in a container.
   */
  @SuppressWarnings("unused")
  public class DefaultAuthorizationHeaderGenerator extends AuthorizationHeaderGeneratorImpl {
      /**
       * Constructs a new authorization header generator.
       *
       * @param config the configuration parameters for the ASAP services
       */
      public DefaultAuthorizationHeaderGenerator(AsapConfiguration config) {
          super(new NimbusJwtSerializer(), createPrivateKeyProvider(config));
      }
  
      private static KeyProvider<PrivateKey> createPrivateKeyProvider(AsapConfiguration config) {
          requireNonNull(config, "config");
          final String url = config.privateKeyUrl();
          return url.isEmpty() ? new NullKeyProvider() : PrivateKeyProviderFactory.createPrivateKeyProvider(URI.create(url));
      }
  }