modelcontextprotocol/java-sdk
Watch
1
0
Fork
You've already forked java-sdk
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Skip session activity tracking when sessionSweepInterval is null

Browse source 
Signed-off-by: Daniel Garnier-Moiroux <git@garnier.wf>
This commit is contained in:
Daniel Garnier-Moiroux 2026-09-16 13:39:38 +02:00 • committed by Daniel Garnier-Moiroux
commit 1178539050
2 changed files with 33 additions and 22 deletions
Download patch file Download diff file Expand all files Collapse all files

50
mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletStreamableServerTransportProvider.java
View file

@ -125,7 +125,8 @@ public class HttpServletStreamableServerTransportProvider extends HttpServlet
/**
* IDs of the sessions which received a request since the last sweep. The set is
* swapped for an empty one on every sweep, so it only ever holds the activity of the
* current interval.
* current interval. Only populated when a sweeper runs, as nothing would ever swap it
* otherwise.
*/
private final AtomicReference<Set<String>> activeSessions = new AtomicReference<>(ConcurrentHashMap.newKeySet());
@ -143,10 +144,10 @@ public class HttpServletStreamableServerTransportProvider extends HttpServlet
private KeepAliveScheduler keepAliveScheduler;
/**
* Periodic eviction of the sessions no client came back to. Activated if
* sessionSweepInterval is set.
* Periodic eviction of the sessions no client came back to. {@code null} if no
* sessionSweepInterval is set, in which case sessions are never reclaimed.
*/
private Disposable sessionSweeper;
private final Disposable sessionSweeper;
/**
* Security validator for validating HTTP requests.
@ -205,23 +206,27 @@ public class HttpServletStreamableServerTransportProvider extends HttpServlet
this.keepAliveScheduler.start();
}
if (sessionSweepInterval != null) {
this.sessionSweeper = Flux.interval(sessionSweepInterval, sessionSweepInterval, Schedulers.boundedElastic())
.doOnNext(tick -> {
// Each sweep runs in its own subscription, so that a sweep failing
// does not terminate the interval and disable sweeping altogether
Mono.fromRunnable(this::sweepSessions)
.doOnError(e -> logger.error("Session sweep failed", e))
.onErrorComplete()
.subscribe();
})
.onErrorComplete(error -> {
logger.error("Session sweeper error", error);
return true;
})
.subscribe();
}
this.sessionSweeper = sessionSweepInterval == null ? null : startSessionSweeper(sessionSweepInterval);
}
/**
* Schedules the periodic eviction of idle sessions.
* @param sessionSweepInterval the interval between two sweeps
* @return the handle on the scheduled sweeps, to be disposed when the transport shuts
* down
*/
private Disposable startSessionSweeper(Duration sessionSweepInterval) {
return Flux.interval(sessionSweepInterval, sessionSweepInterval, Schedulers.boundedElastic()).doOnNext(tick -> {
// Each sweep runs in its own subscription, so that a sweep failing does
// not terminate the interval and disable sweeping altogether
Mono.fromRunnable(this::sweepSessions)
.doOnError(e -> logger.error("Session sweep failed", e))
.onErrorComplete()
.subscribe();
}).onErrorComplete(error -> {
logger.error("Session sweeper error", error);
return true;
}).subscribe();
}
/**
@ -257,6 +262,11 @@ public class HttpServletStreamableServerTransportProvider extends HttpServlet
* @param sessionId the session the current request belongs to
*/
private void markSessionActive(String sessionId) {
if (this.sessionSweeper == null) {
// No sweep ever swaps the set of active sessions, so recording activity would
// only accumulate the ID of every session which ever issued a request
return;
}
this.activeSessions.get().add(sessionId);
}

5
mcp-test/src/test/java/io/modelcontextprotocol/server/HttpServletStreamableIntegrationTests.java
View file

@ -448,13 +448,14 @@ class HttpServletStreamableIntegrationTests extends AbstractMcpClientServerInteg
@Test
void sessionIsNotEvictedWithoutSweepInterval() throws Exception {
// Sweeping is opt-in: a transport configured without an interval keeps its
// sessions until they are deleted or the server shuts down
// Sweeping can be turned off: such a transport keeps its sessions until they are
// deleted or the server shuts down
mcpServerTransportProvider.closeGracefully().block();
mcpServerTransportProvider = HttpServletStreamableServerTransportProvider.builder()
.contextExtractor(TEST_CONTEXT_EXTRACTOR)
.mcpEndpoint(MESSAGE_ENDPOINT)
.keepAliveInterval(KEEP_ALIVE_INTERVAL)
.sessionSweepInterval(null)
.build();
MCP_SERVLET.setDelegate(mcpServerTransportProvider);
prepareAsyncServerBuilder().serverInfo("test-server", "1.0.0").build();