OkHttp — WebSocket Logging

ConnectionsMessages

Setup

Extension function (recommended)

Use the wiretapped() extension on any WebSocketListener:

val request = Request.Builder().url("wss://echo.websocket.org").build()
client.newWebSocket(request, myListener.wiretapped())

Constructor

Alternatively, wrap your listener using the constructor directly:

val listener = WiretapOkHttpWebSocketListener(myListener)
val request = Request.Builder().url("wss://echo.websocket.org").build()
client.newWebSocket(request, listener)

Full example

val myListener = object : WebSocketListener() {
    override fun onOpen(webSocket: WebSocket, response: Response) {
        webSocket.send("Hello!")  // Automatically logged (outgoing)
    }

    override fun onMessage(webSocket: WebSocket, text: String) {
        println("Received: $text")  // Automatically logged (incoming)
    }

    override fun onClosing(webSocket: WebSocket, code: Int, reason: String) {
        webSocket.close(1000, null)
    }

    override fun onClosed(webSocket: WebSocket, code: Int, reason: String) {
        println("Closed: $code $reason")
    }

    override fun onFailure(webSocket: WebSocket, t: Throwable, response: Response?) {
        println("Failed: ${t.message}")
    }
}

val request = Request.Builder().url("wss://echo.websocket.org").build()
client.newWebSocket(request, myListener.wiretapped())

How It Works

WiretapOkHttpWebSocketListener wraps all WebSocketListener callbacks:

Callback	What's Logged
onOpen	Connection opened (status: Open). WebSocket is wrapped for outgoing logging
onMessage(text)	Text message received
onMessage(bytes)	Binary message received (logged as [Binary: N bytes])
onClosing	Status updated to Closing with close code/reason
onClosed	Status updated to Closed with timestamp
onFailure	Status updated to Failed with error message

All events are delegated to your original listener after logging.

Outgoing Message Logging

The webSocket parameter passed to your onOpen() callback is actually a WiretapWebSocket that intercepts send() calls:

override fun onOpen(webSocket: WebSocket, response: Response) {
    // webSocket is a WiretapWebSocket — send() calls are logged automatically
    webSocket.send("Hello!")        // Logged: Text, Sent, "Hello!"
    webSocket.send(byteString)      // Logged: Binary, Sent, "[Binary: N bytes]"
}

All other WebSocket methods (close(), cancel(), request(), queueSize()) pass through to the original.

What Gets Logged

Connection

• URL
• Request headers
• Protocol
• Status transitions (Open → Closing → Closed / Failed)
• Close code and reason
• Failure message

Messages

• Direction (Sent / Received)
• Content type (Text / Binary)
• Content (text or [Binary: N bytes])
• Byte count
• Timestamp