return psv, ErrInvalidQuerySignatureAlgo
	}

	// Initialize signature version '4' structured header.
	preSignV4Values := preSignValues{}

	// Save credential.
	preSignV4Values.Credential, aec = parseCredentialHeader("Credential="+query.Get(xhttp.AmzCredential), region, stype)
	if aec != ErrNone {
		return psv, aec
	}

	var e error
	// Save date in native time.Time.

	_, found := providers[name]
	if found {
		klog.Fatalf("Credential provider %q was registered twice", name)
	}
	klog.V(4).Infof("Registered credential provider %q", name)
	providers[name] = provider
}

// NewDockerKeyring creates a DockerKeyring to use for resolving credentials,
// which draws from the set of registered credential providers.
func NewDockerKeyring() DockerKeyring {
	keyring := &providersDockerKeyring{

            this.resolver = resolver;
        }

        public <CREDENTIAL extends LoginCredential> void resolve(final Class<CREDENTIAL> credentialType,
                final Function<CREDENTIAL, OptionalEntity<FessUser>> oneArgLambda) {
            resolver.resolve(credentialType, credential -> oneArgLambda.apply(credential));
        }
    }

 *
 * ```java
 * if (response.request().header("Authorization") != null) {
 *   return null; // Give up, we've already failed to authenticate.
 * }
 *
 * String credential = Credentials.basic(...)
 * return response.request().newBuilder()
 *     .header("Authorization", credential)
 *     .build();
 * ```
 *
 * When reactive authentication is requested by a proxy server, the response code is 407 and the

	"istio.io/istio/pkg/log"
	"istio.io/istio/security/pkg/util"
)

var gcecredLog = log.RegisterScope("gcecred", "GCE credential fetcher for istio agent")

// Token refresh frequency is default to 5 minutes.
var rotationInterval = 5 * time.Minute

// GCE VM credential needs refresh if remaining life time is below 25 minutes.
var gracePeriod = 25 * time.Minute

        volumeMounts:
        - mountPath: /var/run/secrets/workload-spiffe-uds
          name: workload-socket
        - mountPath: /var/run/secrets/credential-uds
          name: credential-socket
        - mountPath: /var/run/secrets/workload-spiffe-credentials
          name: workload-certs
        - mountPath: /var/run/secrets/istio
          name: istiod-ca-cert
        - mountPath: /var/lib/istio/data

      timeoutSeconds: 3
    volumeMounts:
    - mountPath: /var/run/secrets/workload-spiffe-uds
      name: workload-socket
    - mountPath: /var/run/secrets/credential-uds
      name: credential-socket
    - mountPath: /var/run/secrets/workload-spiffe-credentials
      name: workload-certs
    - mountPath: /var/run/secrets/istio
      name: istiod-ca-cert
    - mountPath: /var/lib/istio/data
      name: istio-data

        volumeMounts:
        - mountPath: /var/run/secrets/workload-spiffe-uds
          name: workload-socket
        - mountPath: /var/run/secrets/credential-uds
          name: credential-socket
        - mountPath: /var/run/secrets/workload-spiffe-credentials
          name: workload-certs
        - mountPath: /var/run/secrets/istio
          name: istiod-ca-cert
        - mountPath: /var/lib/istio/data

      timeoutSeconds: 3
    volumeMounts:
    - mountPath: /var/run/secrets/workload-spiffe-uds
      name: workload-socket
    - mountPath: /var/run/secrets/credential-uds
      name: credential-socket
    - mountPath: /var/run/secrets/workload-spiffe-credentials
      name: workload-certs
    - mountPath: /var/run/secrets/istio
      name: istiod-ca-cert
    - mountPath: /var/lib/istio/data
      name: istio-data

    responses += response
    routes += route
    if (!schemeMatches(response) || credential == null) return null
    val header =
      when (response.code) {
        407 -> "Proxy-Authorization"
        else -> "Authorization"
      }
    return response.request.newBuilder()
      .addHeader(header, credential)
      .build()
  }

  private fun schemeMatches(response: Response): Boolean {