From 23becf9619f1fff7d905387ca7c6866e90af3213 Mon Sep 17 00:00:00 2001
From: Mathew Sutcliffe <oktal3700@gmail.com>
Date: Wed, 8 Nov 2017 21:27:22 +0000
Subject: [PATCH] Ref T184 Use CTokenBucket to throttle identical log messages.

---
 src/blackmisc/loghandler.cpp  | 19 +++++++++++++++++++
 src/blackmisc/loghandler.h    |  3 +++
 src/blackmisc/statusmessage.h |  2 +-
 3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/src/blackmisc/loghandler.cpp b/src/blackmisc/loghandler.cpp
index 574c305cf..cfe8ffff5 100644
--- a/src/blackmisc/loghandler.cpp
+++ b/src/blackmisc/loghandler.cpp
@@ -126,6 +126,25 @@ namespace BlackMisc
 
     void CLogHandler::logLocalMessage(const CStatusMessage &statusMessage)
     {
+        using namespace BlackMisc::PhysicalQuantities;
+        auto bucket = m_tokenBuckets.find(statusMessage);
+        if (bucket == m_tokenBuckets.end()) { bucket = m_tokenBuckets.insert(statusMessage, { { 5, CTime(1, CTimeUnit::s()), 1 }, 0 }); }
+        if (! bucket->first.tryConsume())
+        {
+            bucket->second++;
+            return;
+        }
+        if (bucket->second > 0)
+        {
+            auto copy = statusMessage;
+            copy.appendMessage(QStringLiteral(" (+%1 identical messages)").arg(bucket->second));
+            bucket->second = 0;
+
+            logMessage(copy);
+            emit localMessageLogged(copy);
+            return;
+        }
+
         logMessage(statusMessage);
         emit localMessageLogged(statusMessage);
     }
diff --git a/src/blackmisc/loghandler.h b/src/blackmisc/loghandler.h
index 178a6bbce..99d6a1274 100644
--- a/src/blackmisc/loghandler.h
+++ b/src/blackmisc/loghandler.h
@@ -16,8 +16,10 @@
 #include "blackmisc/logcategory.h"
 #include "blackmisc/logpattern.h"
 #include "blackmisc/statusmessage.h"
+#include "blackmisc/tokenbucket.h"
 
 #include <QList>
+#include <QHash>
 #include <QMetaMethod>
 #include <QMetaObject>
 #include <QObject>
@@ -105,6 +107,7 @@ namespace BlackMisc
         QList<PatternPair> m_patternHandlers;
         QList<CLogPatternHandler *> handlersForMessage(const CStatusMessage &message) const;
         void removePatternHandler(CLogPatternHandler *);
+        QHash<CStatusMessage, std::pair<CTokenBucket, int>> m_tokenBuckets;
     };
 
     /*!
diff --git a/src/blackmisc/statusmessage.h b/src/blackmisc/statusmessage.h
index 3afff1a1e..d6c4bcb60 100644
--- a/src/blackmisc/statusmessage.h
+++ b/src/blackmisc/statusmessage.h
@@ -362,7 +362,7 @@ namespace BlackMisc
             BLACK_METAMEMBER(severity),
             BLACK_METAMEMBER(message),
             BLACK_METAMEMBER(args),
-            BLACK_METAMEMBER(timestampMSecsSinceEpoch)
+            BLACK_METAMEMBER(timestampMSecsSinceEpoch, 0, DisabledForHashing | DisabledForComparison)
         );
     };