Make empty and '*' debugModules to result in all debug messages to be printed

Previously there was no way to enable debug messages for non-module
code. But we want to be able to issue debug messages e.g. from
Services or framework. In addition, the empty debugModules (that is
also the default value) leading to no debug messages being issued
seemed now a poor choice (given the amount of complaints in the past
on how difficult MessageLogger is to configure, especially for debug
messages).

Author: makortel

FWCore/MessageService/Readme.md

@@ -66,24 +66,32 @@ process.MessageLogger.MyCat = dict(limit = 0)
 The `MessageLogger` PSet knows that all _extra_ parameter labels must be of type `cms.untracked.PSet` so one can use a python `dict` set specific parameters for that PSet and allow all other parameters to use their default default values.
 
 
+## Have all debug messages be shown
 
-## Have debug message show for a given module
 By default, all `LogDebug` code is actually removed at compilation time so any messages you want to see have to be recompiled after setting the `EDM_ML_DEBUG` compilation parameter
 
 ```bash
 > export USER_CXXFLAGS="-DEDM_ML_DEBUG"
 > scram b ...
 ```
 
-Then in the `MessageLogger` configuration you need to lower the `threshold` to `"DEBUG"` and then say you want debug messages from the module. So if your module uses the label `myModule` in the configuration, you'd specify
+Then in the `MessageLogger` configuration you need to lower the `threshold` to `"DEBUG"`
+```python
+process.MessageLogger.cerr.threshold = "DEBUG"
+```
+
+The default `MessageLogger` configuration leads to all debug messages to be printed (also outside modules).
 
+
+## Have debug message show for a given module
+
+It is possible to restrict the shown debug messages to specific module(s). For example, if your module uses the label `myModule` in the configuration, you'd specify
 ```python
 process.MessageLogger.cerr.threshold = "DEBUG"
 process.MessageLogger.debugModules = ["myModule"]
 ```
 
-If you are not interested in a particular module but instead want to see all debug messages, you can instead set `debugModules` using `*`
-
+For backwards compatibility, setting `debugModules` to `*` has the same effect as setting `debugModules` empty, i.e. showing all debug messages.
 ```python
 process.MessageLogger.cerr.threshold = "DEBUG"
 process.MessageLogger.debugModules = ["*"]

FWCore/MessageService/plugins/MessageLogger.cc

@@ -183,18 +183,19 @@ namespace edm {
       // set up for tracking whether current module is debug-enabled
       // (and info-enabled and warning-enabled)
       if (debugModules.empty()) {
-        anyDebugEnabled_ = false;                       // change log 11
-        MessageDrop::instance()->debugEnabled = false;  // change log 1
+        anyDebugEnabled_ = true;
+        everyDebugEnabled_ = true;
+        MessageDrop::instance()->debugEnabled = true;
       } else {
         anyDebugEnabled_ = true;  // change log 11
         MessageDrop::instance()->debugEnabled = false;
         // this will be over-ridden when specific modules are entered
       }
 
-      // if ( debugModules.empty()) anyDebugEnabled_ = true; // wrong; change log 11
       for (vString::const_iterator it = debugModules.begin(); it != debugModules.end(); ++it) {
         if (*it == "*") {
           everyDebugEnabled_ = true;
+          MessageDrop::instance()->debugEnabled = true;
         } else {
           debugEnabledModules_.insert(*it);
         }

FWCore/MessageService/src/ThreadSafeLogMessageLoggerScribe.cc

@@ -915,7 +915,10 @@ namespace edm {
         topDesc.addUntracked<std::vector<std::string>>("suppressFwkInfo", {});
         topDesc.addUntracked<std::vector<std::string>>("suppressWarning", {});
         topDesc.addUntracked<std::vector<std::string>>("suppressError", {});
-        topDesc.addUntracked<std::vector<std::string>>("debugModules", {});
+        topDesc.addUntracked<std::vector<std::string>>("debugModules", {})
+            ->setComment(
+                "Set to limit the DEBUG-level messages to modules with these labels. If empty or contains '*', all "
+                "DEBUG messages (also those outside modules) will be issued (if allowed by the threshold parameter).");
 
         edm::ParameterSetDescription category;
         category.addUntracked<int>("reportEvery", 1);

FWCore/MessageService/test/BuildFile.xml

@@ -61,6 +61,20 @@
     <use name="FWCore/Framework"/>
   </library>
 
+  <library file="UnitTestService_H.cc" name="UnitTestService_H">
+    <flags EDM_PLUGIN="1"/>
+    <use name="FWCore/MessageLogger"/>
+    <use name="FWCore/ParameterSet"/>
+    <use name="FWCore/ServiceRegistry"/>
+  </library>
+
+  <library file="UnitTestService_Hd.cc" name="UnitTestService_Hd">
+    <flags EDM_PLUGIN="1"/>
+    <use name="FWCore/MessageLogger"/>
+    <use name="FWCore/ParameterSet"/>
+    <use name="FWCore/ServiceRegistry"/>
+  </library>
+
   <library file="UnitTestClient_I.cc" name="UnitTestClient_I">
     <flags EDM_PLUGIN="1"/>
     <use name="FWCore/MessageLogger"/>

FWCore/MessageService/test/UnitTestService_H.cc

@@ -0,0 +1,20 @@
+#ifdef EDM_ML_DEBUG
+#undef EDM_ML_DEBUG
+#endif
+
+#include "FWCore/MessageLogger/interface/MessageLogger.h"
+#include "FWCore/ParameterSet/interface/ParameterSet.h"
+#include "FWCore/ServiceRegistry/interface/ActivityRegistry.h"
+
+namespace edmtest {
+  class UnitTestService_H {
+  public:
+    UnitTestService_H(edm::ParameterSet const& iConfig, edm::ActivityRegistry& iRegistry) {
+      iRegistry.watchPreSourceNextTransition(
+          []() { LogDebug("cat_S") << "Message from watchPreSourceNextTransition"; });
+    }
+  };
+}  // namespace edmtest
+
+#include "FWCore/ServiceRegistry/interface/ServiceMaker.h"
+DEFINE_FWK_SERVICE(edmtest::UnitTestService_H);

FWCore/MessageService/test/UnitTestService_Hd.cc

@@ -0,0 +1,20 @@
+#ifndef EDM_ML_DEBUG
+#define EDM_ML_DEBUG
+#endif
+
+#include "FWCore/MessageLogger/interface/MessageLogger.h"
+#include "FWCore/ParameterSet/interface/ParameterSet.h"
+#include "FWCore/ServiceRegistry/interface/ActivityRegistry.h"
+
+namespace edmtest {
+  class UnitTestService_Hd {
+  public:
+    UnitTestService_Hd(edm::ParameterSet const& iConfig, edm::ActivityRegistry& iRegistry) {
+      iRegistry.watchPreSourceNextTransition(
+          []() { LogDebug("cat_S") << "Message from watchPreSourceNextTransition"; });
+    }
+  };
+}  // namespace edmtest
+
+#include "FWCore/ServiceRegistry/interface/ServiceMaker.h"
+DEFINE_FWK_SERVICE(edmtest::UnitTestService_Hd);

FWCore/MessageService/test/u13_cfg.py

@@ -49,4 +49,4 @@
 
 process.p = cms.Path(process.sendSomeMessages)
 
-
+process.add_(cms.Service("edmtest::UnitTestService_H"))

FWCore/MessageService/test/u13d_cfg.py

@@ -43,7 +43,7 @@
         )
       )
     ),
-    debugModules = cms.untracked.vstring('*'),
+    debugModules = cms.untracked.vstring(),
 )
 
 process.maxEvents = cms.untracked.PSet(
@@ -56,4 +56,4 @@
 
 process.p = cms.Path(process.sendSomeMessages)
 
-
+process.add_(cms.Service("edmtest::UnitTestService_Hd"))

FWCore/MessageService/test/u1_cfg.py

@@ -1,7 +1,7 @@
 # Unit test configuration file for MessageLogger service:
 # threshold levels for destinations
 # limit=0 for a category (needed to avoid time stamps in files to be compared)
-# enabling all (*) LogDebug, with one destination responding
+# enabling all LogDebug, with one destination responding
 # verify that by default, the threshold for a destination is INFO
 
 import FWCore.ParameterSet.Config as cms
@@ -56,7 +56,7 @@
             noTimeStamps = cms.untracked.bool(True)
         )
     ),
-    debugModules = cms.untracked.vstring('*'),
+    debugModules = cms.untracked.vstring(),
 )
 
 process.CPU = cms.Service("CPU",

FWCore/MessageService/test/u1d_cfg.py

@@ -1,7 +1,7 @@
 # Unit test configuration file for MessageLogger service:
 # threshold levels for destinations
 # limit=0 for a category (needed to avoid time stamps in files to be compared)
-# enabling all (*) LogDebug, with one destination responding
+# enabling all LogDebug, with one destination responding
 # verify that by default, the threshold for a destination is INFO
 # test done with debug enabled
 
@@ -57,7 +57,7 @@
           noTimeStamps = cms.untracked.bool(True)
       )
     ),
-    debugModules = cms.untracked.vstring('*')
+    debugModules = cms.untracked.vstring()
 )
 
 process.CPU = cms.Service("CPU",