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WebSocketLifecycleEventReceiver

[Source]

WebSocket lifecycle callbacks delivered to the connection actor.

All callbacks have default no-op implementations. Override only the callbacks your actor needs. For most servers, on_text_message() or on_binary_message() is the main callback — it delivers complete, reassembled messages after all fragments are received and validated.

Override on_upgrade_request() to inspect the HTTP upgrade request before accepting the connection (e.g., checking the URI path or Origin header). Return false to reject with 403 Forbidden.

Callbacks are invoked synchronously inside the actor that owns the WebSocketServer. The protocol class handles framing, masking, fragmentation, and the close handshake internally, delivering only application-level events through this interface.

trait ref WebSocketLifecycleEventReceiver

Public Functions

on_upgrade_request

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Called when a valid upgrade request is received, before the connection is accepted.

Return true to accept (sends 101 Switching Protocols) or false to reject (sends 403 Forbidden and closes TCP). The default implementation accepts all connections.

fun ref on_upgrade_request(
  request: UpgradeRequest val)
: Bool val

Parameters

Returns

on_open

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Called after the WebSocket handshake completes successfully.

fun ref on_open(
  request: UpgradeRequest val)
: None val

Parameters

Returns

on_text_message

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Called when a complete text message is received.

fun ref on_text_message(
  data: String val)
: None val

Parameters

Returns

on_binary_message

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Called when a complete binary message is received.

fun ref on_binary_message(
  data: Array[U8 val] val)
: None val

Parameters

Returns

on_closed

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Called when the WebSocket connection closes.

close_status indicates why the connection closed — a named primitive for standard codes (e.g., CloseNormal), CloseNoStatusReceived when the close frame had no payload, CloseAbnormalClosure when TCP dropped without a close handshake, or OtherCloseCode for application-defined or IANA-registered codes without named primitives.

close_reason is the UTF-8 reason string from the close frame, or empty when no reason was provided or the close was abnormal.

fun ref on_closed(
  close_status: (CloseNormal val | CloseGoingAway val | CloseProtocolError val | 
    CloseUnsupportedData val | CloseInvalidPayload val | ClosePolicyViolation val | 
    CloseMessageTooBig val | CloseInternalError val | CloseNoStatusReceived val | 
    CloseAbnormalClosure val | OtherCloseCode val),
  close_reason: String val)
: None val

Parameters

Returns

on_throttled

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Called when backpressure is applied on the connection.

fun ref on_throttled()
: None val

Returns

on_unthrottled

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Called when backpressure is released on the connection.

fun ref on_unthrottled()
: None val

Returns