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Socket.setTimeout()

Sets the inactivity timeout for the socket. When the socket has been idle for timeout milliseconds without receiving data, a timeout event is emitted.

The socket doesn’t automatically close after a timeout. The connection remains open until you explicitly call destroy(). To disable a previously set timeout, pass 0.

Signature

JavaScript 
socket.setTimeout(timeout)

Parameters

ParameterTypeDescription
timeoutnumberInactivity timeout in milliseconds. Pass 0 to disable

Returns

TypeDescription
SocketThe socket instance, for method chaining

Example

JavaScript 
import { Socket } from "k6/x/tcp"

export default async function () {
  const socket = new Socket()

  const closed = new Promise((resolve) => {
    socket.on("close", () => {
      console.log("Connection closed")
      resolve()
    })
  })

  socket.on("data", (data) => {
    const str = String.fromCharCode.apply(null, new Uint8Array(data))
    console.log("Received:", str)
    // Reset the timeout after each data event
    socket.setTimeout(5000)
  })

  socket.on("timeout", () => {
    console.log("No data received for 5 seconds — closing")
    socket.destroy()
  })

  socket.on("error", (err) => {
    console.error("Error:", err)
  })

  const host = __ENV.TCP_HOST || "localhost"
  const port = __ENV.TCP_PORT || "8080"

  await socket.connect(port, host)
  console.log("Connected — waiting for data (5s timeout)")

  // Set timeout after connecting; no immediate write so the idle timer can fire
  socket.setTimeout(5000)

  await closed
}