Create -loglevel configuration option

- add a -loglevel=<level>|<category:level> config option to allow users
  to set a global -loglevel and category-specific log levels. LogPrintLevel
  messages with a higher severity level than -loglevel will not be printed
  in the debug log.

- for now, this config option is debug-only during the migration to
  severity-based logging

- update unit and functional tests

Co-authored-by: "Jon Atack <jon@atack.com>"

6 files changed, 29 insertions, 1 deletions

diff --git a/src/init.cpp b/src/init.cpp
index 4606b77e9f..2b40e882a4 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -915,6 +915,7 @@ bool AppInitParameterInteraction(const ArgsManager& args, bool use_syscall_sandb
 
     // ********************************************************* Step 3: parameter-to-internal-flags
     init::SetLoggingCategories(args);
+    init::SetLoggingLevel(args);
 
     fCheckBlockIndex = args.GetBoolArg("-checkblockindex", chainparams.DefaultConsistencyChecks());
     fCheckpointsEnabled = args.GetBoolArg("-checkpoints", DEFAULT_CHECKPOINTS_ENABLED);
diff --git a/src/init/common.cpp b/src/init/common.cpp
index bdd7f16307..3261c18e5a 100644
--- a/src/init/common.cpp
+++ b/src/init/common.cpp
@@ -11,6 +11,7 @@
 #include <logging.h>
 #include <node/interface_ui.h>
 #include <tinyformat.h>
+#include <util/string.h>
 #include <util/system.h>
 #include <util/time.h>
 #include <util/translation.h>
@@ -28,6 +29,7 @@ void AddLoggingArgs(ArgsManager& argsman)
         ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
     argsman.AddArg("-debugexclude=<category>", "Exclude debugging information for a category. Can be used in conjunction with -debug=1 to output debug logs for all categories except the specified category. This option can be specified multiple times to exclude multiple categories.", ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
     argsman.AddArg("-logips", strprintf("Include IP addresses in debug output (default: %u)", DEFAULT_LOGIPS), ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
+    argsman.AddArg("-loglevel=<level>|<category>:<level>", strprintf("Set the global or per-category severity level for logging categories enabled with the -debug configuration option or the logging RPC: %s (default=%s); warning and error levels are always logged. If <category>:<level> is supplied, the setting will override the global one and may be specified multiple times to set multiple category-specific levels. <category> can be: %s.", LogInstance().LogLevelsString(), LogInstance().LogLevelToStr(BCLog::DEFAULT_LOG_LEVEL), LogInstance().LogCategoriesString()), ArgsManager::DISALLOW_NEGATION | ArgsManager::DISALLOW_ELISION | ArgsManager::DEBUG_ONLY, OptionsCategory::DEBUG_TEST);
     argsman.AddArg("-logtimestamps", strprintf("Prepend debug output with timestamp (default: %u)", DEFAULT_LOGTIMESTAMPS), ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
 #ifdef HAVE_THREAD_LOCAL
     argsman.AddArg("-logthreadnames", strprintf("Prepend debug output with name of the originating thread (only available on platforms supporting thread_local) (default: %u)", DEFAULT_LOGTHREADNAMES), ArgsManager::ALLOW_ANY, OptionsCategory::DEBUG_TEST);
@@ -55,6 +57,26 @@ void SetLoggingOptions(const ArgsManager& args)
     fLogIPs = args.GetBoolArg("-logips", DEFAULT_LOGIPS);
 }
 
+void SetLoggingLevel(const ArgsManager& args)
+{
+    if (args.IsArgSet("-loglevel")) {
+        for (const std::string& level_str : args.GetArgs("-loglevel")) {
+            if (level_str.find_first_of(':', 3) == std::string::npos) {
+                // user passed a global log level, i.e. -loglevel=<level>
+                if (!LogInstance().SetLogLevel(level_str)) {
+                    InitWarning(strprintf(_("Unsupported global logging level -loglevel=%s. Valid values: %s."), level_str, LogInstance().LogLevelsString()));
+                }
+            } else {
+                // user passed a category-specific log level, i.e. -loglevel=<category>:<level>
+                const auto& toks = SplitString(level_str, ':');
+                if (!(toks.size() == 2 && LogInstance().SetCategoryLogLevel(toks[0], toks[1]))) {
+                    InitWarning(strprintf(_("Unsupported category-specific logging level -loglevel=%s. Expected -loglevel=<category>:<loglevel>. Valid categories: %s. Valid loglevels: %s."), level_str, LogInstance().LogCategoriesString(), LogInstance().LogLevelsString()));
+                }
+            }
+        }
+    }
+}
+
 void SetLoggingCategories(const ArgsManager& args)
 {
     if (args.IsArgSet("-debug")) {
diff --git a/src/init/common.h b/src/init/common.h
index 2c7f485908..53c860c297 100644
--- a/src/init/common.h
+++ b/src/init/common.h
@@ -14,6 +14,7 @@ namespace init {
 void AddLoggingArgs(ArgsManager& args);
 void SetLoggingOptions(const ArgsManager& args);
 void SetLoggingCategories(const ArgsManager& args);
+void SetLoggingLevel(const ArgsManager& args);
 bool StartLogging(const ArgsManager& args);
 void LogPackageVersion();
 } // namespace init
diff --git a/src/logging.cpp b/src/logging.cpp
index 214f6af9a7..0de74c4913 100644
--- a/src/logging.cpp
+++ b/src/logging.cpp
@@ -199,7 +199,7 @@ bool GetLogCategory(BCLog::LogFlags& flag, const std::string& str)
     return false;
 }
 
-std::string LogLevelToStr(BCLog::Level level)
+std::string BCLog::Logger::LogLevelToStr(BCLog::Level level) const
 {
     switch (level) {
     case BCLog::Level::Debug:
diff --git a/src/logging.h b/src/logging.h
index 680eb47f4b..1288efa0fe 100644
--- a/src/logging.h
+++ b/src/logging.h
@@ -189,6 +189,9 @@ namespace BCLog {
         //! Returns a string with all user-selectable log levels.
         std::string LogLevelsString() const;
 
+        //! Returns the string representation of a log level.
+        std::string LogLevelToStr(BCLog::Level level) const;
+
         bool DefaultShrinkDebugFile() const;
     };
 
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index 30d26ecf79..872310f1ca 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -108,6 +108,7 @@ BasicTestingSetup::BasicTestingSetup(const std::string& chainName, const std::ve
             "-logsourcelocations",
             "-logtimemicros",
             "-logthreadnames",
+            "-loglevel=debug",
             "-debug",
             "-debugexclude=libevent",
             "-debugexclude=leveldb",