added message history

Author: sy-c

doc/releaseNotes.md

@@ -141,3 +141,7 @@ This file describes the main feature changes for each InfoLogger released versio
 
 ## v2.6.0 - 24/01/2024
 - Updated SWIG version requirement to allow generation of Python3 bindings.
+
+## next
+- Added functions to keep a history of latest log messages: see historyReset() and historyGetSummary().
+- Added function to register error codes descriptions to format message summaries in history.

include/InfoLogger/InfoLogger.hxx

@@ -29,6 +29,7 @@
 #include <type_traits>
 #include <atomic>
 #include <chrono>
+#include <vector>
 
 // here are some macros to help including source code info in infologger messages
 // to be used to quickly specify "infoLoggerMessageOption" argument in some logging functions
@@ -396,6 +397,33 @@ class InfoLogger
   /// Reset counters of messages
   void resetMessageCount();
 
+
+  /// Functions to keep an history of messages
+
+  /// Reset history
+  /// This function enables storing next log messages injected in a buffer (eg for later error reporting). Existing history is cleared.
+  /// parameters:
+  /// messagesToKeep: number of messages stored in buffer
+  /// rotate: if set, newer messages overwrite stored messages stored in buffer (i.e. history keeps latest messages). By default, history keeps first messages.
+  /// filterSeverity: messages with lower severity are not stored in history.
+  /// filterLevel: messages with lower level are not stored in history.
+  void historyReset(unsigned int messagesToKeep = 0, bool rotate = false, InfoLogger::Severity filterSeverity = InfoLogger::Severity::Error, InfoLogger::Level filterLevel = InfoLogger::Level::Support);
+
+  /// Get a summary of messages stored in history buffer.
+  /// The buffer is not cleared (use historyReset to do so).
+  /// Each message is a simplified text.
+  /// parameters:
+  /// summary: a variable where to store a copy of the messages currently available in history buffer
+  /// returns: 0 on success
+  void historyGetSummary(std::vector<std::string> &summary);
+
+  /// Function to register a table converting error codes to a meaningful text.
+  /// Used for formatting message summary.
+  /// parameters:
+  /// errorCodes: a vector of key-value pairs. First is the error code, second is a text description
+  /// clear: if set, existing table is cleared. Otherwise, it is appended (in this case, duplication of codes is not checked. First one found is used).
+  void registerErrorCodes(const std::vector<std::pair<int, std::string>> errorCodes, bool clear = 0);
+
   ///////////////////////
   /// internals
   ///////////////////////

src/InfoLogger.cxx

@@ -34,6 +34,8 @@
 #include <thread>
 #include <memory>
 #include <functional>
+#include <queue>
+#include <mutex>
 
 #include "InfoLoggerMessageHelper.h"
 #include "Common/LineBuffer.h"
@@ -167,6 +169,26 @@ int infoLoggerLogDebug(InfoLoggerHandle handle, const char* message, ...)
   return err;
 }
 
+
+// function to convert severities to a priority number (high priority = small number)
+int getIdFromSeverity(InfoLogger::Severity s) {
+  switch (s) {
+    case InfoLogger::Severity::Fatal :
+      return 1;
+    case InfoLogger::Severity::Error :
+      return 2;
+    case InfoLogger::Severity::Warning :
+      return 3;
+    case InfoLogger::Severity::Info :
+      return 4;
+    case InfoLogger::Severity::Debug :
+      return 5;
+    default:
+      return 6;
+  }
+}
+
+
 /////////////////////////////////////////////////////////
 
 namespace AliceO2
@@ -420,7 +442,18 @@ class InfoLogger::Impl
   bool filterDiscardFileEnabled = false; // when set, discarded messages go to file
   bool filterDiscardFileIgnoreDebug = false; // when set, debug messages even when discarded and filterDiscardFileEnabled=true do not go to file
   SimpleLog filterDiscardFile; // file object where to save discarded messages
+
+  // history
+  unsigned int historyMessagesToKeep = 0;
+  bool historyRotate = false;
+  int historyFilterSeverity = -1;
+  int historyFilterLevel = -1;
+  std::queue<std::string> historyMessages; // messages currently in history queue
+  std::mutex historyMutex; // lock to avoid concurrent calls on history functions 
 
+  // error code conversion table
+  std::vector<std::pair<int, std::string>> errorCodesTable; // first: error code, second: description
+
   // message flood prevention
   // constants
   bool flood_protection = 1;         // if set, flood protection mechanism enabled
@@ -787,6 +820,32 @@ int InfoLogger::Impl::pushMessage(const InfoLoggerMessageOption& options, const
     msgHelper.MessageToText(&msg, buffer, sizeof(buffer), InfoLoggerMessageHelper::Format::Debug);
     puts(buffer);
   }
+
+  // keep history
+  std::unique_lock<std::mutex> lock(historyMutex);
+  if (historyMessagesToKeep > 0) {
+    if (historyRotate || (historyMessagesToKeep > historyMessages.size())) {
+      if ((getIdFromSeverity(options.severity) <= historyFilterSeverity) && (options.level <= historyFilterLevel)) {
+        std::string summary;
+	summary += "code "+ std::to_string(options.errorCode);
+	if (options.errorCode != undefinedMessageOption.errorCode) {
+	  for(const auto &p: errorCodesTable) {
+	    if (p.first == options.errorCode) {
+              summary += " : " + p.second;
+	      break;
+	    }
+	  }
+	  summary += " - ";
+	}
+	summary += messageBody;
+        historyMessages.push(std::move(summary));
+	if (historyRotate && (historyMessagesToKeep > historyMessages.size())) {
+	  historyMessages.pop();
+	}
+      }
+    }
+  }
+
   return 0;
 }
 
@@ -1282,6 +1341,37 @@ void InfoLogger::resetMessageCount() {
   mPimpl->resetMessageCount();
 }
 
+void InfoLogger::historyReset(unsigned int messagesToKeep, bool rotate, InfoLogger::Severity filterSeverity, InfoLogger::Level filterLevel) {
+  std::unique_lock<std::mutex> lock(mPimpl->historyMutex);
+  mPimpl->historyMessagesToKeep = messagesToKeep;
+  mPimpl->historyRotate = rotate;
+  mPimpl->historyFilterSeverity = getIdFromSeverity(filterSeverity);
+  mPimpl->historyFilterLevel = (int)filterLevel;
+  mPimpl->historyMessages = {}; // clear queue
+}
+
+void InfoLogger::historyGetSummary(std::vector<std::string> &summary) {
+  std::unique_lock<std::mutex> lock(mPimpl->historyMutex);
+  summary.clear();
+  summary.reserve(mPimpl->historyMessages.size());
+  while (!mPimpl->historyMessages.empty())
+  {
+    summary.push_back(std::move(mPimpl->historyMessages.front()));
+    mPimpl->historyMessages.pop();
+  }
+}
+
+void InfoLogger::registerErrorCodes(const std::vector<std::pair<int, std::string>> errorCodes, bool clear) {
+  std::unique_lock<std::mutex> lock(mPimpl->historyMutex);
+  if (clear) {
+    mPimpl->errorCodesTable.clear();
+  }
+  for(const auto &c: errorCodes) {
+    mPimpl->errorCodesTable.push_back({c.first, c.second});
+  }
+}
+
+
 // end of namespace
 } // namespace InfoLogger
 } // namespace AliceO2

test/testInfoLogger.cxx

@@ -25,6 +25,23 @@ int main()
 {
   InfoLogger theLog;
 
+  if (0) {
+    theLog.historyReset(2);
+    theLog.registerErrorCodes({{123, "error"}, {124, "fatal"}});
+    theLog.log(LogInfoSupport_(100), "test info");
+    theLog.log(LogErrorSupport_(123), "test error 123");
+    theLog.log(LogInfoDevel_(100), "test info");
+    theLog.log(LogFatalSupport_(124), "test fatal 124");
+    std::vector<std::string> m;
+    theLog.historyGetSummary(m);
+    printf("log summary:\n");
+    for(const auto&s: m) {
+      printf("  %s\n",s.c_str());
+    }
+    printf("\n");
+    return 0;
+  }
+
   theLog.log("infoLogger message test");
   printf("Message on stdout (initial stdout)\n");
   theLog.setStandardRedirection(1);