TopicMatcher matching to parent when using '#' wildcard.

Author: fpagliughi

include/mqtt/topic_matcher.h

@@ -312,22 +312,28 @@ class topic_matcher
             auto snode = std::move(nodes_.back());
             nodes_.pop_back();
 
+            const auto map_end = snode.node_->children.end();
+            typename node_map::iterator child;
+
             // If we're at the end of the topic fields, we either have a value,
             // or need to move on to the next node to search.
             if (snode.fields_.empty()) {
                 pval_ = snode.node_->content.get();
-                if (!pval_)
+                if (!pval_) {
+                    // ...but a '#' matches the parent topic
+                    if ((child = snode.node_->children.find("#")) != map_end) {
+                        pval_ = child->second->content.get();
+                        return;
+                    }
                     this->next();
+                }
                 return;
             }
 
             // Get the next field of the topic to search
             auto field = std::move(snode.fields_.front());
             snode.fields_.pop_front();
 
-            typename node_map::iterator child;
-            const auto map_end = snode.node_->children.end();
-
             // Look for an exact match
             if ((child = snode.node_->children.find(field)) != map_end) {
                 nodes_.push_back({child->second.get(), snode.fields_});

src/topic.cpp

@@ -109,7 +109,10 @@ bool topic_filter::matches(const string& topic) const
 {
     auto n = fields_.size();
 
-    // Edge case of topic_filter("")
+    // Spec: All Topic Names and Topic Filters MUST be at least one
+    //   character long [MQTT-4.7.3-1]
+    // So, an empty filter can't match anything, and is technically an
+    // error.
     if (n == 0) {
         return false;
     }
@@ -118,7 +121,7 @@ bool topic_filter::matches(const string& topic) const
     auto nt = topic_fields.size();
 
     // Filter can't match a topic that is shorter
-    if (n > nt) {
+    if (n > nt && !(n == nt + 1 && fields_[n - 1] == "#")) {
         return false;
     }
 
@@ -140,6 +143,9 @@ bool topic_filter::matches(const string& topic) const
         if (fields_[i] == "#") {
             break;
         }
+        if (i == nt && i < n - 1) {
+            return fields_[i + 1] == "#";
+        }
         if (fields_[i] != "+" && fields_[i] != topic_fields[i]) {
             return false;
         }

test/unit/test_async_client.cpp

@@ -578,8 +578,7 @@ TEST_CASE("async_client publish 5 args", "[client]")
 
     const void* payload{PAYLOAD.data()};
     const size_t payload_size{PAYLOAD.size()};
-    delivery_token_ptr token_pub{
-        cli.publish(TOPIC, payload, payload_size, GOOD_QOS, RETAINED)
+    delivery_token_ptr token_pub{cli.publish(TOPIC, payload, payload_size, GOOD_QOS, RETAINED)
     };
     REQUIRE(token_pub);
     token_pub->wait_for(TIMEOUT);
@@ -738,8 +737,8 @@ TEST_CASE("async_client subscribe many topics 2 args_single", "[client]")
     cli.connect()->wait();
     REQUIRE(cli.is_connected());
 
-    mqtt::const_string_collection_ptr TOPIC_1_COLL{mqtt::string_collection::create({"TOPIC0"}
-    )};
+    mqtt::const_string_collection_ptr TOPIC_1_COLL{mqtt::string_collection::create({"TOPIC0"})
+    };
     iasync_client::qos_collection GOOD_QOS_1_COLL{0};
     try {
         cli.subscribe(TOPIC_1_COLL, GOOD_QOS_1_COLL)->wait_for(TIMEOUT);

test/unit/test_async_client_v3.cpp

@@ -534,8 +534,8 @@ class async_client_v3_test : public CppUnit::TestFixture
 
         // NOTE: Only tokens for messages with QOS=1 and QOS=2 are kept. That's
         // why the vector's size does not account for QOS=0 message tokens
-        std::vector<mqtt::delivery_token_ptr> tokens_pending{cli.get_pending_delivery_tokens(
-        )};
+        std::vector<mqtt::delivery_token_ptr> tokens_pending{cli.get_pending_delivery_tokens()
+        };
         CPPUNIT_ASSERT_EQUAL(2, static_cast<int>(tokens_pending.size()));
 
         mqtt::token_ptr token_disconn{cli.disconnect()};
@@ -831,8 +831,7 @@ class async_client_v3_test : public CppUnit::TestFixture
         CPPUNIT_ASSERT(cli.is_connected());
 
         mqtt::test::dummy_action_listener listener;
-        mqtt::token_ptr token_sub{
-            cli.subscribe(TOPIC_COLL, GOOD_QOS_COLL, &CONTEXT, listener)
+        mqtt::token_ptr token_sub{cli.subscribe(TOPIC_COLL, GOOD_QOS_COLL, &CONTEXT, listener)
         };
         CPPUNIT_ASSERT(token_sub);
         token_sub->wait_for(TIMEOUT);

test/unit/test_topic.cpp

@@ -232,6 +232,7 @@ TEST_CASE("topic matches", "[topic_filter]")
         REQUIRE(filt.matches("my/topic/name"));
         REQUIRE(filt.matches("my/topic/id"));
         REQUIRE(filt.matches("my/topic/name/and/id"));
+        REQUIRE(filt.matches("my/topic"));
 
         REQUIRE(!filt.matches("my/other/name"));
         REQUIRE(!filt.matches("my/other/id"));
@@ -244,14 +245,14 @@ TEST_CASE("topic matches", "[topic_filter]")
     SECTION("should_match")
     {
         REQUIRE(topic_filter{"foo/bar"}.matches("foo/bar"));
-        REQUIRE(
-            topic_filter{
-                "foo/+",
-            }
-                .matches("foo/bar")
-        );
+        REQUIRE(topic_filter{
+            "foo/+",
+        }
+                    .matches("foo/bar"));
         REQUIRE(topic_filter{"foo/+/baz"}.matches("foo/bar/baz"));
         REQUIRE(topic_filter{"foo/+/#"}.matches("foo/bar/baz"));
+        REQUIRE(topic_filter("foo/bar/#").matches("foo/bar/baz"));
+        REQUIRE(topic_filter("foo/bar/#").matches("foo/bar"));
         REQUIRE(topic_filter{"A/B/+/#"}.matches("A/B/B/C"));
         REQUIRE(topic_filter{"#"}.matches("foo/bar/baz"));
         REQUIRE(topic_filter{"#"}.matches("/foo/bar"));

test/unit/test_topic_matcher.cpp

@@ -69,6 +69,8 @@ TEST_CASE("matcher matches", "[topic_matcher]")
     REQUIRE((topic_matcher<int>{{"foo/+", 42}}.has_match("foo/bar")));
     REQUIRE((topic_matcher<int>{{"foo/+/baz", 42}}.has_match("foo/bar/baz")));
     REQUIRE((topic_matcher<int>{{"foo/+/#", 42}}.has_match("foo/bar/baz")));
+    REQUIRE((topic_matcher<int>{{"foo/bar/#", 42}}.has_match("foo/bar/baz")));
+    REQUIRE((topic_matcher<int>{{"foo/bar/#", 42}}.has_match("foo/bar")));
     REQUIRE((topic_matcher<int>{{"A/B/+/#", 42}}.has_match("A/B/B/C")));
     REQUIRE((topic_matcher<int>{{"#", 42}}.has_match("foo/bar/baz")));
     REQUIRE((topic_matcher<int>{{"#", 42}}.has_match("/foo/bar")));