The WebSocketTransformer provides the ability to upgrade a HttpRequest to a WebSocket connection. It supports both upgrading a single HttpRequest and upgrading a stream of HttpRequests.

To upgrade a single HttpRequest use the static upgrade method.

HttpServer server;
server.listen((request) {
  if (...) {
    WebSocketTransformer.upgrade(request).then((websocket) {
  } else {
    // Do normal HTTP request processing.

To transform a stream of HttpRequest events as it implements a stream transformer that transforms a stream of HttpRequest into a stream of WebSockets by upgrading each HttpRequest from the HTTP or HTTPS server, to the WebSocket protocol.

server.transform(new WebSocketTransformer()).listen((webSocket) => ...);

This transformer strives to implement WebSockets as specified by RFC6455.


Static Methods

isUpgradeRequest(HttpRequest request) → bool

Checks whether the request is a valid WebSocket upgrade request.

upgrade(HttpRequest request, {dynamic protocolSelector(List<String> protocols)}) → Future<WebSocket>

Upgrades a HttpRequest to a WebSocket connection. If the request is not a valid WebSocket upgrade request an HTTP response with status code 500 will be returned. Otherwise the returned future will complete with the WebSocket when the upgrade pocess is complete.


WebSocketTransformer({dynamic protocolSelector(List<String> protocols)})

Create a new WebSocketTransformer.


bind(Stream<HttpRequest> stream) → Stream<WebSocket>

Transform the incoming stream's events.