Package org.springframework.web.socket.server.support

Class AbstractHandshakeHandler

java.lang.Object
org.springframework.web.socket.server.support.AbstractHandshakeHandler
All Implemented Interfaces:
Lifecycle, HandshakeHandler
Direct Known Subclasses:
DefaultHandshakeHandler
public abstract class AbstractHandshakeHandler extends Object implements HandshakeHandler, Lifecycle
A base class for HandshakeHandler implementations, independent of the Servlet API.

Performs initial validation of the WebSocket handshake request - possibly rejecting it through the appropriate HTTP status code - while also allowing its subclasses to override various parts of the negotiation process (e.g. origin validation, sub-protocol negotiation, extensions negotiation, etc).

If the negotiation succeeds, the actual upgrade is delegated to a server-specific RequestUpgradeStrategy, which will update the response as necessary and initialize the WebSocket.

Since:
4.2
Author:
Rossen Stoyanchev, Juergen Hoeller
See Also:

  • Field Details

    • logger

      protected final Log logger

  • Constructor Details

  • Method Details

    • getRequestUpgradeStrategy

      public RequestUpgradeStrategy getRequestUpgradeStrategy()
      Return the RequestUpgradeStrategy for WebSocket requests.

    • setSupportedProtocols

      public void setSupportedProtocols(String... protocols)
      Use this property to configure the list of supported sub-protocols. The first configured sub-protocol that matches a client-requested sub-protocol is accepted. If there are no matches the response will not contain a Sec-WebSocket-Protocol header.

      Note that if the WebSocketHandler passed in at runtime is an instance of SubProtocolCapable then there is no need to explicitly configure this property. That is certainly the case with the built-in STOMP over WebSocket support. Therefore, this property should be configured explicitly only if the WebSocketHandler does not implement SubProtocolCapable.

    • getSupportedProtocols

      public String[] getSupportedProtocols()
      Return the list of supported sub-protocols.

    • start

      public void start()
      Description copied from interface: Lifecycle
      Start this component.

      Should not throw an exception if the component is already running.

      In the case of a container, this will propagate the start signal to all components that apply.

      Specified by:
      start in interface Lifecycle
      See Also:

    • doStart

      protected void doStart()

    • stop

      public void stop()
      Description copied from interface: Lifecycle
      Stop this component, typically in a synchronous fashion, such that the component is fully stopped upon return of this method. Consider implementing SmartLifecycle and its stop(Runnable) variant when asynchronous stop behavior is necessary.

      Note that this stop notification is not guaranteed to come before destruction: On regular shutdown, Lifecycle beans will first receive a stop notification before the general destruction callbacks are being propagated; however, on hot refresh during a context's lifetime or on aborted refresh attempts, a given bean's destroy method will be called without any consideration of stop signals upfront.

      Should not throw an exception if the component is not running (not started yet).

      In the case of a container, this will propagate the stop signal to all components that apply.

      Specified by:
      stop in interface Lifecycle
      See Also:

    • doStop

      protected void doStop()

    • isRunning

      public boolean isRunning()
      Description copied from interface: Lifecycle
      Check whether this component is currently running.

      In the case of a container, this will return true only if all components that apply are currently running.

      Specified by:
      isRunning in interface Lifecycle
      Returns:
      whether the component is currently running

    • doHandshake

      public final boolean doHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler, Map<String,Object> attributes) throws HandshakeFailureException
      Description copied from interface: HandshakeHandler
      Initiate the handshake.
      Specified by:
      doHandshake in interface HandshakeHandler
      Parameters:
      request - the current request
      response - the current response
      wsHandler - the handler to process WebSocket messages; see PerConnectionWebSocketHandler for providing a handler with per-connection lifecycle.
      attributes - the attributes from the HTTP handshake to associate with the WebSocket session; the provided attributes are copied, the original map is not used.
      Returns:
      whether the handshake negotiation was successful or not. In either case the response status, headers, and body will have been updated to reflect the result of the negotiation
      Throws:
      HandshakeFailureException - thrown when handshake processing failed to complete due to an internal, unrecoverable error, i.e. a server error as opposed to a failure to successfully negotiate the handshake.

    • handleInvalidUpgradeHeader

      protected void handleInvalidUpgradeHeader(ServerHttpRequest request, ServerHttpResponse response) throws IOException
      Throws:
      IOException

    • handleInvalidConnectHeader

      protected void handleInvalidConnectHeader(ServerHttpRequest request, ServerHttpResponse response) throws IOException
      Throws:
      IOException

    • isWebSocketVersionSupported

      protected boolean isWebSocketVersionSupported(WebSocketHttpHeaders httpHeaders)

    • getSupportedVersions

      protected String[] getSupportedVersions()

    • handleWebSocketVersionNotSupported

      protected void handleWebSocketVersionNotSupported(ServerHttpRequest request, ServerHttpResponse response)

    • isValidOrigin

      protected boolean isValidOrigin(ServerHttpRequest request)
      Return whether the request Origin header value is valid or not. By default, all origins as considered as valid. Consider using an OriginHandshakeInterceptor for filtering origins if needed.

    • selectProtocol

      @Nullable protected String selectProtocol(List<String> requestedProtocols, WebSocketHandler webSocketHandler)
      Perform the sub-protocol negotiation based on requested and supported sub-protocols. For the list of supported sub-protocols, this method first checks if the target WebSocketHandler is a SubProtocolCapable and then also checks if any sub-protocols have been explicitly configured with setSupportedProtocols(String...).
      Parameters:
      requestedProtocols - the requested sub-protocols
      webSocketHandler - the WebSocketHandler that will be used
      Returns:
      the selected protocols or null
      See Also:

    • determineHandlerSupportedProtocols

      protected final List<String> determineHandlerSupportedProtocols(WebSocketHandler handler)
      Determine the sub-protocols supported by the given WebSocketHandler by checking whether it is an instance of SubProtocolCapable.
      Parameters:
      handler - the handler to check
      Returns:
      a list of supported protocols, or an empty list if none available

    • filterRequestedExtensions

      protected List<WebSocketExtension> filterRequestedExtensions(ServerHttpRequest request, List<WebSocketExtension> requestedExtensions, List<WebSocketExtension> supportedExtensions)
      Filter the list of requested WebSocket extensions.

      As of 4.1, the default implementation of this method filters the list to leave only extensions that are both requested and supported.

      Parameters:
      request - the current request
      requestedExtensions - the list of extensions requested by the client
      supportedExtensions - the list of extensions supported by the server
      Returns:
      the selected extensions or an empty list

    • determineUser

      @Nullable protected Principal determineUser(ServerHttpRequest request, WebSocketHandler wsHandler, Map<String,Object> attributes)
      A method that can be used to associate a user with the WebSocket session in the process of being established. The default implementation calls ServerHttpRequest.getPrincipal()

      Subclasses can provide custom logic for associating a user with a session, for example for assigning a name to anonymous users (i.e. not fully authenticated).

      Parameters:
      request - the handshake request
      wsHandler - the WebSocket handler that will handle messages
      attributes - handshake attributes to pass to the WebSocket session
      Returns:
      the user for the WebSocket session, or null if not available