/** The HTTP {@code ETag} header field name. */
  public static final String ETAG = "ETag";

  /** The HTTP {@code Expires} header field name. */
  public static final String EXPIRES = "Expires";

  /** The HTTP {@code Last-Modified} header field name. */
  public static final String LAST_MODIFIED = "Last-Modified";

  /** The HTTP {@code Link} header field name. */

         */
        void onRegistrationFailed(WitnessRegistration registration, Exception error);

        /**
         * Called when a witness registration expires.
         *
         * @param registration the expired registration
         */
        void onRegistrationExpired(WitnessRegistration registration);
    }

    /**
     * Creates a new witness client.
     *

func checkPostPolicy(formValues http.Header, postPolicyForm PostPolicyForm) error {
	// Check if policy document expiry date is still not reached
	if !postPolicyForm.Expiration.After(UTCNow()) {
		return fmt.Errorf("Invalid according to Policy: Policy expired")
	}

	// mustFindInPolicy is a map to list all the keys that we must find in the policy as

	if context.Cause(ctx) != nil {
		xioutil.SafeClose(expireCh)
		return context.Cause(ctx)
	}
	pushToExpire()
	// Send any remaining objects downstream
	if len(toDel) > 0 {
		select {
		case <-ctx.Done():
		case expireCh <- toDel:
		}
	}
	xioutil.SafeClose(expireCh)

	<-expireDoneCh // waits for the expire goroutine to complete
	wk.Wait()      // waits for all expire workers to retire

			z.ContentEncoding, bts, err = msgp.ReadStringBytes(bts)
			if err != nil {
				err = msgp.WrapError(err, "ContentEncoding")
				return
			}
		case "Expires":
			z.Expires, bts, err = msgp.ReadTimeBytes(bts)
			if err != nil {
				err = msgp.WrapError(err, "Expires")
				return
			}
		case "CacheControl":
			z.CacheControl, bts, err = msgp.ReadStringBytes(bts)
			if err != nil {

                }
            }
        }

        /**
         * Waits for the crawling thread to terminate within a specified time limit.
         * This method blocks until the thread completes or the timeout expires.
         *
         * @param mills maximum time to wait in milliseconds
         */
        public void awaitTermination(final long mills) {
            try {
                join(mills);

      Header("content-range", ""),
      Header("content-type", ""),
      Header("cookie", ""),
      Header("date", ""),
      Header("etag", ""),
      Header("expect", ""),
      Header("expires", ""),
      Header("from", ""),
      Header("host", ""),
      Header("if-match", ""),
      Header("if-modified-since", ""),
      Header("if-none-match", ""),
      Header("if-range", ""),

   *
   * <ol>
   *   <li>calls {@link ExecutorService#shutdown()}, disabling acceptance of new submitted tasks.
   *   <li>awaits executor service termination for half of the specified timeout.
   *   <li>if the timeout expires, it calls {@link ExecutorService#shutdownNow()}, cancelling
   *       pending tasks and interrupting running tasks.
   *   <li>awaits executor service termination for the other half of the specified timeout.
   * </ol>
   *

	VersionID            string    // Specifies the versionID which needs to be overwritten or read
	MTime                time.Time // Is only set in POST/PUT operations
	Expires              time.Time // Is only used in POST/PUT operations

	DeleteMarker            bool // Is only set in DELETE operations for delete marker replication

     * This method is called automatically after the bean construction is complete.
     * The cache is configured with a maximum size of 100 entries and expires after 10 minutes.
     */
    @PostConstruct
    public void init() {
        if (logger.isDebugEnabled()) {
            logger.debug("Initializing {}", this.getClass().getSimpleName());
        }