org.springframework.messaging.simp.user

Class DefaultUserDestinationResolver

java.lang.Object

org.springframework.messaging.simp.user.DefaultUserDestinationResolver

All Implemented Interfaces:

UserDestinationResolver

public class DefaultUserDestinationResolver
extends java.lang.Object
implements UserDestinationResolver

A default implementation of UserDestinationResolver that relies on a SimpUserRegistry to find active sessions for a user.

When a user attempts to subscribe, e.g. to "/user/queue/position-updates", the "/user" prefix is removed and a unique suffix added based on the session id, e.g. "/queue/position-updates-useri9oqdfzo" to ensure different users can subscribe to the same logical destination without colliding.

When sending to a user, e.g. "/user/{username}/queue/position-updates", the "/user/{username}" prefix is removed and a suffix based on active session id's is added, e.g. "/queue/position-updates-useri9oqdfzo".

Since:

4.0

Author:

Rossen Stoyanchev, Brian Clozel

Constructor Summary

Constructors

Constructor and Description
DefaultUserDestinationResolver(SimpUserRegistry userRegistry) Create an instance that will access user session id information through the provided registry.

Method Summary

Modifier and Type	Method and Description
protected boolean	checkDestination(java.lang.String destination, java.lang.String requiredPrefix)
java.lang.String	getDestinationPrefix() Return the configured prefix for user destinations.
SimpUserRegistry	getSimpUserRegistry() Return the configured SimpUserRegistry.
protected java.lang.String	getTargetDestination(java.lang.String sourceDestination, java.lang.String actualDestination, java.lang.String sessionId, java.lang.String user) This method determines how to translate the source "user" destination to an actual target destination for the given active user session.
boolean	isRemoveLeadingSlash() Whether to remove the leading slash from target destinations.
UserDestinationResult	resolveDestination(Message<?> message) Resolve the given message with a user destination to one or more messages with actual destinations, one for each active user session.
void	setPathMatcher(PathMatcher pathMatcher) Deprecated. as of 4.3.14 this property is no longer used and is replaced by setRemoveLeadingSlash(boolean) that indicates more explicitly whether to keep the leading slash which may or may not be the case regardless of how the PathMatcher is configured.
void	setRemoveLeadingSlash(boolean remove) Use this property to indicate whether the leading slash from translated user destinations should be removed or not.
void	setUserDestinationPrefix(java.lang.String prefix) The prefix used to identify user destinations.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultUserDestinationResolver

public DefaultUserDestinationResolver(SimpUserRegistry userRegistry)

Create an instance that will access user session id information through the provided registry.

Parameters:

userRegistry - the registry, never null

Method Detail

getSimpUserRegistry

public SimpUserRegistry getSimpUserRegistry()

Return the configured SimpUserRegistry.

setUserDestinationPrefix

public void setUserDestinationPrefix(java.lang.String prefix)

The prefix used to identify user destinations. Any destinations that do not start with the given prefix are not be resolved.

The default prefix is "/user/".

Parameters:

prefix - the prefix to use

getDestinationPrefix

public java.lang.String getDestinationPrefix()

Return the configured prefix for user destinations.

setRemoveLeadingSlash

public void setRemoveLeadingSlash(boolean remove)

Use this property to indicate whether the leading slash from translated user destinations should be removed or not. This depends on the destination prefixes the message broker is configured with.

By default this is set to false, i.e. "do not change the target destination", although AbstractMessageBrokerConfiguration may change that to true if the configured destinations do not have a leading slash.

Parameters:

remove - whether to remove the leading slash

Since:

4.3.14

isRemoveLeadingSlash

public boolean isRemoveLeadingSlash()

Whether to remove the leading slash from target destinations.

Since:

4.3.14

setPathMatcher

@Deprecated
public void setPathMatcher(@Nullable
                                       PathMatcher pathMatcher)

Deprecated. as of 4.3.14 this property is no longer used and is replaced by setRemoveLeadingSlash(boolean) that indicates more explicitly whether to keep the leading slash which may or may not be the case regardless of how the PathMatcher is configured.

Provide the PathMatcher in use for working with destinations which in turn helps to determine whether the leading slash should be kept in actual destinations after removing the userDestinationPrefix.

By default actual destinations have a leading slash, e.g. /queue/position-updates which makes sense with brokers that support destinations with slash as separator. When a PathMatcher is provided that supports an alternative separator, then resulting destinations won't have a leading slash, e.g. jms.queue.position-updates.

Parameters:

pathMatcher - the PathMatcher used to work with destinations

Since:

4.3

resolveDestination

@Nullable
public UserDestinationResult resolveDestination(Message<?> message)

Description copied from interface: UserDestinationResolver

Resolve the given message with a user destination to one or more messages with actual destinations, one for each active user session.

Specified by:

resolveDestination in interface UserDestinationResolver

Parameters:

message - the message to try to resolve

Returns:

0 or more target messages (one for each active session), or null if the source message does not contain a user destination.

checkDestination

protected boolean checkDestination(java.lang.String destination,
                                   java.lang.String requiredPrefix)

getTargetDestination

@Nullable
protected java.lang.String getTargetDestination(java.lang.String sourceDestination,
                                                          java.lang.String actualDestination,
                                                          java.lang.String sessionId,
                                                          @Nullable
                                                          java.lang.String user)

This method determines how to translate the source "user" destination to an actual target destination for the given active user session.

Parameters:

sourceDestination - the source destination from the input message.

actualDestination - a subset of the destination without any user prefix.

sessionId - the id of an active user session, never null.

user - the target user, possibly null, e.g if not authenticated.

Returns:

a target destination, or null if none

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object