mDNS: Improved Receiver-Side Logging

Change-Id: Id318fd53dda291160baeb5a710e8aca0b5e12371
Reviewed-on: https://chromium-review.googlesource.com/c/openscreen/+/2102903
Reviewed-by: Max Yakimakha <yakimakha@chromium.org>
Commit-Queue: Ryan Keane <rwkeane@google.com>

2 files changed, 21 insertions, 7 deletions

diff --git a/discovery/mdns/mdns_querier.cc b/discovery/mdns/mdns_querier.cc
index 3d9ac152..adc23b1c 100644
--- a/discovery/mdns/mdns_querier.cc
+++ b/discovery/mdns/mdns_querier.cc
@@ -200,30 +200,40 @@ void MdnsQuerier::OnMessageReceived(const MdnsMessage& message) {
   OSP_DCHECK(task_runner_->IsRunningOnTaskRunner());
   OSP_DCHECK(message.type() == MessageType::Response);
 
+  OSP_DVLOG << "Received mDNS Response message with "
+            << message.answers().size() << " answers and "
+            << message.additional_records().size()
+            << " additional records. Processing...";
+
   // Add any records that are relevant for this querier.
   bool found_relevant_records = false;
+  int processed_count = 0;
   for (const MdnsRecord& record : message.answers()) {
     if (ShouldAnswerRecordBeProcessed(record)) {
       ProcessRecord(record);
+      OSP_DVLOG << "\tProcessing answer record for domain '"
+                << record.name().ToString() << "' of type '"
+                << record.dns_type() << "'...";
       found_relevant_records = true;
+      processed_count++;
     }
   }
 
-  OSP_DVLOG << "Received mDNS Response message with "
-            << message.answers().size() << " answers and "
-            << message.additional_records().size()
-            << " additional records. Processing...";
-
   // If any of the message's answers are relevant, add all additional records.
   // Else, since the message has already been received and parsed, use any
   // individual records relevant to this querier to update the cache.
   for (const MdnsRecord& record : message.additional_records()) {
     if (found_relevant_records || ShouldAnswerRecordBeProcessed(record)) {
+      OSP_DVLOG << "\tProcessing additional record for domain '"
+                << record.name().ToString() << "' of type '"
+                << record.dns_type() << "'...";
       ProcessRecord(record);
+      processed_count++;
     }
   }
 
-  OSP_DVLOG << "\tmDNS Response processed!";
+  OSP_DVLOG << "\tmDNS Response processed (" << processed_count
+            << " records accepted)!";
 
   // TODO(crbug.com/openscreen/83): Check authority records.
   // TODO(crbug.com/openscreen/84): Cap size of cache, to avoid memory blowups
diff --git a/discovery/mdns/mdns_receiver.cc b/discovery/mdns/mdns_receiver.cc
index 1f9b95da..8dc9fdd1 100644
--- a/discovery/mdns/mdns_receiver.cc
+++ b/discovery/mdns/mdns_receiver.cc
@@ -69,14 +69,18 @@ void MdnsReceiver::OnRead(UdpSocket* socket,
     return;
   }
 
-  OSP_DVLOG << "Received new mDNS Message";
   if (message.type() == MessageType::Response) {
     for (ResponseClient* client : response_clients_) {
       client->OnMessageReceived(message);
     }
+    if (response_clients_.empty()) {
+      OSP_DVLOG << "Response message dropped. No response client registered...";
+    }
   } else {
     if (query_callback_) {
       query_callback_(message, packet.source());
+    } else {
+      OSP_DVLOG << "Query message dropped. No query client registered...";
     }
   }
 }