http2session.ping([payload, ]callback)

版本历史

版本	变更
v18.0.0	Passing an invalid callback to the `callback` argument now throws `ERR_INVALID_ARG_TYPE` instead of `ERR_INVALID_CALLBACK`.
v8.9.3	新增于: v8.9.3

payload <Buffer> | <TypedArray> | <DataView> 可选的 ping 负载。
callback <Function>
返回：<boolean>

向已连接的 HTTP/2 对等方发送 PING 帧。必须提供一个 callback 函数。如果 PING 发送成功，该方法将返回 true，否则返回 false。

🌐 Sends a PING frame to the connected HTTP/2 peer. A callback function must be provided. The method will return true if the PING was sent, false otherwise.

maxOutstandingPings 配置选项决定了未确认 ping 的最大数量。默认最大值为 10。

🌐 The maximum number of outstanding (unacknowledged) pings is determined by the maxOutstandingPings configuration option. The default maximum is 10.

如果提供，payload 必须是一个包含 8 字节数据的 Buffer、TypedArray 或 DataView，这些数据将随 PING 发送，并在 ping 确认时返回。

🌐 If provided, the payload must be a Buffer, TypedArray, or DataView containing 8 bytes of data that will be transmitted with the PING and returned with the ping acknowledgment.

回调函数将接收三个参数：一个错误参数，如果 PING 被成功确认，该参数将为 null；一个 duration 参数，报告从发送 ping 到收到确认所经过的毫秒数；以及一个包含 8 字节 PING 数据的 Buffer。

🌐 The callback will be invoked with three arguments: an error argument that will be null if the PING was successfully acknowledged, a duration argument that reports the number of milliseconds elapsed since the ping was sent and the acknowledgment was received, and a Buffer containing the 8-byte PING payload.

session.ping(Buffer.from('abcdefgh'), (err, duration, payload) => {
  if (!err) {
    console.log(`Ping acknowledged in ${duration} milliseconds`);
    console.log(`With payload '${payload.toString()}'`);
  }
});

如果未指定 payload 参数，默认的负载将是标记 PING 持续时间开始的 64 位时间戳（小端序）。

🌐 If the payload argument is not specified, the default payload will be the 64-bit timestamp (little endian) marking the start of the PING duration.