if err := target.init(); err != nil {
		return false, err
	}
	return target.isActive()
}

func (target *PostgreSQLTarget) isActive() (bool, error) {
	if err := target.db.Ping(); err != nil {
		if IsConnErr(err) {
			return false, store.ErrNotConnected
		}
		return false, err
	}
	return true, nil
}

            final PingResponse pingResponse = searchEngineClient.ping();
            writeJsonResponse(pingResponse.getStatus() == 0 ? HttpServletResponse.SC_OK : HttpServletResponse.SC_SERVICE_UNAVAILABLE,
                    "\"data\":" + pingResponse.getMessage());
        } catch (final Exception e) {
            if (logger.isDebugEnabled()) {
                logger.debug("Failed to process a ping request.", e);
            }

    }
  }

  @Test fun emptyPingCallsCallback() {
    data.write("8900".decodeHex()) // Empty ping
    clientReader.processNextFrame()
    callback.assertPing(EMPTY)
  }

  @Test fun pingCallsCallback() {
    data.write("890548656c6c6f".decodeHex()) // Ping with "Hello"
    clientReader.processNextFrame()
    callback.assertPing("Hello".encodeUtf8())
  }

		if peer == nil {
			continue
		}
		peer.Listen(ctx, mergeCh, values)
	}

	var (
		emptyEventTicker <-chan time.Time
		keepAliveTicker  <-chan time.Time
	)

	if p := values.Get("ping"); p != "" {
		pingInterval, err := strconv.Atoi(p)
		if err != nil {
			writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrInvalidQueryParams), r.URL)
			return
		}
		if pingInterval < 1 {

    }
  }

  @Test fun pingRoundTrip() {
    val expectedPayload1 = 7
    val expectedPayload2 = 8
    writeMedium(frame, 8) // length
    frame.writeByte(Http2.TYPE_PING)
    frame.writeByte(Http2.FLAG_ACK)
    frame.writeInt(0) // connection-level
    frame.writeInt(expectedPayload1)
    frame.writeInt(expectedPayload2)

    // Check writer sends the same bytes.

  internal const val OPCODE_CONTINUATION = 0x0
  internal const val OPCODE_TEXT = 0x1
  internal const val OPCODE_BINARY = 0x2

  internal const val OPCODE_CONTROL_CLOSE = 0x8
  internal const val OPCODE_CONTROL_PING = 0x9
  internal const val OPCODE_CONTROL_PONG = 0xa

  /**
   * Maximum length of frame payload. Larger payloads, if supported by the frame type, can use the
   * special values [PAYLOAD_SHORT] or [PAYLOAD_LONG].
   */

   * {@code Ping-From}</a> header field name.
   *
   * @since 19.0
   */
  public static final String PING_FROM = "Ping-From";
  /**
   * The HTTP <a href="http://html.spec.whatwg.org/multipage/semantics.html#hyperlink-auditing">
   * {@code Ping-To}</a> header field name.
   *
   * @since 19.0
   */
  public static final String PING_TO = "Ping-To";

  /**
   * The HTTP <a

	biggerBufMin = 32 << 10

	// This is the maximum size of bigger buffers.
	biggerBufMax = maxBufferSize

	// If there is a queue, merge up to this many messages.
	maxMergeMessages = 30

	// clientPingInterval will ping the remote handler every 15 seconds.
	// Clients disconnect when we exceed 2 intervals.
	clientPingInterval = 15 * time.Second

	// Deadline for single (non-streaming) requests to complete.

    )
    val openAtNanos = System.nanoTime()
    newWebSocket()
    clientListener.assertOpen()
    clientListener.assertFailure(
      SocketTimeoutException::class.java,
      "sent ping but didn't receive pong within 500ms (after 0 successful ping/pongs)",
    )
    latch.countDown()
    val elapsedUntilFailure = System.nanoTime() - openAtNanos
    assertThat(TimeUnit.NANOSECONDS.toMillis(elapsedUntilFailure).toDouble())

                                  description: The ring/modulo hash load balancer
                                    implements consistent hashing to backend hosts.
                                  properties:
                                    minimumRingSize:
                                      description: The minimum number of virtual nodes
                                        to use for the hash ring.