Fix Will not being sent if will delay greater than session expiry.

Closes #1401. Thanks to Will Lisac.

ChangeLog.txt

@@ -8,6 +8,8 @@ Broker:
   `use_subject_as_username` being disconnected on SIGHUP. Closes #1402.
 - Improve error messages in some situations when clients disconnect. Reduces
   the number of "Socket error on client X, disconnecting" messages.
+- Fix Will for v5 clients not being sent if will delay interval was greater
+  than the session expiry interval. Closes #1401.
 
 Client library:
 - Fix reconnect backoff for the situation where connections are dropped rather

src/session_expiry.c

@@ -100,7 +100,10 @@ void session_expiry__check(struct mosquitto_db *db, time_t now)
 			context = item->context;
 			session_expiry__remove(context);
 
+			/* Session has now expired, so clear interval */
 			context->session_expiry_interval = 0;
+			/* Session has expired, so will delay should be cleared. */
+			context->will_delay_interval = 0;
 			context__send_will(db, context);
 			context__add_to_disused(db, context);
 		}else{

test/broker/07-will-delay-session-expiry.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python3
+
+# Test whether a client that connects with a will delay that is longer than
+# their session expiry interval has their will published.
+# MQTT 5
+# https://github.com/eclipse/mosquitto/issues/1401
+
+from mosq_test_helper import *
+
+rc = 1
+keepalive = 60
+
+mid = 1
+connect1_packet = mosq_test.gen_connect("will-test", keepalive=keepalive, proto_ver=5)
+connack1_packet = mosq_test.gen_connack(rc=0, proto_ver=5)
+
+will_props = mqtt5_props.gen_uint32_prop(mqtt5_props.PROP_WILL_DELAY_INTERVAL, 4)
+connect_props = mqtt5_props.gen_uint32_prop(mqtt5_props.PROP_SESSION_EXPIRY_INTERVAL, 2)
+
+connect2_packet = mosq_test.gen_connect("will-helper", keepalive=keepalive, proto_ver=5, properties=connect_props, will_topic="will/test", will_payload=b"will delay", will_qos=2, will_properties=will_props)
+connack2_packet = mosq_test.gen_connack(rc=0, proto_ver=5)
+
+subscribe_packet = mosq_test.gen_subscribe(mid, "will/test", 0, proto_ver=5)
+suback_packet = mosq_test.gen_suback(mid, 0, proto_ver=5)
+
+publish_packet = mosq_test.gen_publish("will/test", qos=0, payload="will delay", proto_ver=5)
+
+port = mosq_test.get_port()
+broker = mosq_test.start_broker(filename=os.path.basename(__file__), port=port)
+
+try:
+    sock1 = mosq_test.do_client_connect(connect1_packet, connack1_packet, timeout=30, port=port, connack_error="connack1")
+    mosq_test.do_send_receive(sock1, subscribe_packet, suback_packet, "suback")
+
+    sock2 = mosq_test.do_client_connect(connect2_packet, connack2_packet, timeout=30, port=port, connack_error="connack2")
+    time.sleep(1)
+    sock2.close()
+
+    # Wait for session to expire
+    time.sleep(3)
+    if mosq_test.expect_packet(sock1, "publish", publish_packet):
+        rc = 0
+
+    sock1.close()
+finally:
+    broker.terminate()
+    broker.wait()
+    (stdo, stde) = broker.communicate()
+    if rc:
+        print(stde.decode('utf-8'))
+        exit(rc)
+

test/broker/Makefile

@@ -138,6 +138,7 @@ endif
 07 :
 	./07-will-delay-reconnect.py
 	./07-will-delay-recover.py
+	./07-will-delay-session-expiry.py
 	./07-will-delay.py
 	./07-will-disconnect-with-will.py
 	./07-will-invalid-utf8.py

test/broker/test.py

@@ -112,6 +112,7 @@ tests = [
 
     (1, './07-will-delay-reconnect.py'),
     (1, './07-will-delay-recover.py'),
+    (1, './07-will-delay-session-expiry.py'),
     (1, './07-will-delay.py'),
     (1, './07-will-disconnect-with-will.py'),
     (1, './07-will-invalid-utf8.py'),