Package uk.ac.manchester.spinnaker.alloc.proxy

Class SpinWSHandler

java.lang.Object

org.springframework.web.socket.handler.AbstractWebSocketHandler

org.springframework.web.socket.handler.BinaryWebSocketHandler

uk.ac.manchester.spinnaker.alloc.proxy.SpinWSHandler

All Implemented Interfaces:

HandshakeInterceptor, WebSocketHandler

@Component
public class SpinWSHandler
extends BinaryWebSocketHandler
implements HandshakeInterceptor

Initial handler for web sockets. Maps a particular websocket to a proxy handler that processes messages received and sends messages the other way.

Author:

Donal Fellows

Field Summary

Fields

Modifier and Type	Field	Description
static final String	PATH	The path that we match in this handler.

Method Summary

Modifier and Type	Method	Description
void	afterConnectionClosed(WebSocketSession session, CloseStatus status)	Websocket closed; disconnect the proxy handler.
void	afterConnectionEstablished(WebSocketSession session)	Websocket established; connect to the proxy handler.
void	afterHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler, Exception exception)	Empty method to satisfy interface.
boolean	beforeHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler, Map<String,Object> attributes)	Look up the job that websocket is being created for and attach it to the websocket's attributes.
protected final void	closed(WebSocketSession session, ProxyCore proxy, SpallocAPI.Job job)	Connection closed.
protected final void	delegateToProxy(BinaryMessage message, ProxyCore proxy)	Message was sent to us.
protected void	handleBinaryMessage(WebSocketSession session, BinaryMessage message)	Websocket message received, dispatch it to the proxy for handling.
void	handleTransportError(WebSocketSession session, Throwable exception)	Log exceptions from the transport level.
protected final void	initProxyCore(WebSocketSession session, SpallocAPI.Job job)	Connection established and job looked up.

Methods inherited from class org.springframework.web.socket.handler.BinaryWebSocketHandler

handleTextMessage

Methods inherited from class org.springframework.web.socket.handler.AbstractWebSocketHandler

handleMessage, handlePongMessage, supportsPartialMessages

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

PATH

public static final String PATH

The path that we match in this handler.

See Also:

• Constant Field Values

Method Details

beforeHandshake

public boolean beforeHandshake(ServerHttpRequest request,
 ServerHttpResponse response,
 WebSocketHandler wsHandler,
 Map<String,Object> attributes)

Look up the job that websocket is being created for and attach it to the websocket's attributes.

Specified by:

beforeHandshake in interface HandshakeInterceptor

Returns:

Whether we found the job and attached it.

afterHandshake

public void afterHandshake(ServerHttpRequest request,
 ServerHttpResponse response,
 WebSocketHandler wsHandler,
 Exception exception)

Empty method to satisfy interface.

Specified by:

afterHandshake in interface HandshakeInterceptor

afterConnectionEstablished

public void afterConnectionEstablished(WebSocketSession session)

Websocket established; connect to the proxy handler.

Specified by:

afterConnectionEstablished in interface WebSocketHandler

Overrides:

afterConnectionEstablished in class AbstractWebSocketHandler

Parameters:

session - The websocket session to connect.

afterConnectionClosed

public void afterConnectionClosed(WebSocketSession session,
 CloseStatus status)

Websocket closed; disconnect the proxy handler.

Specified by:

afterConnectionClosed in interface WebSocketHandler

Overrides:

afterConnectionClosed in class AbstractWebSocketHandler

Parameters:

session - The websocket session to disconnect.

status - Why the session closed. (Unimportant for this code)

handleBinaryMessage

protected void handleBinaryMessage(WebSocketSession session,
 BinaryMessage message)
                            throws Exception

Websocket message received, dispatch it to the proxy for handling.

Overrides:

handleBinaryMessage in class AbstractWebSocketHandler

Parameters:

session - The websocket session that the message was received on.

message - The received message.

Throws:

Exception

handleTransportError

public void handleTransportError(WebSocketSession session,
 Throwable exception)

Log exceptions from the transport level. Except for EOFException because that's just fine and comes up in a normal disconnect.

Specified by:

handleTransportError in interface WebSocketHandler

Overrides:

handleTransportError in class AbstractWebSocketHandler

Parameters:

session - The websocket session that had the error.

exception - What happened.

initProxyCore

protected final void initProxyCore(WebSocketSession session,
 SpallocAPI.Job job)

Connection established and job looked up. Make a proxy.

Parameters:

session - The Websocket session

job - The job extracted from the websocket path

Throws:

RequestFailedException.NotFound - If the job ID can't be mapped to a job

RequestFailedException - If the job doesn't have an allocated machine

closed

protected final void closed(WebSocketSession session,
 ProxyCore proxy,
 SpallocAPI.Job job)

Connection closed.

Parameters:

session - The Websocket session

proxy - The proxy handler for our custom protocol

job - What job we are working for

delegateToProxy

protected final void delegateToProxy(BinaryMessage message,
 ProxyCore proxy)
                              throws IOException

Message was sent to us.

Parameters:

message - The body of the message.

proxy - The socket proxy will be handling the message

Throws:

IOException - If the proxy fails to handle the message in a bad way