From eb183b0d3b0af1fac2a62a27db39551d0e71cd6a Mon Sep 17 00:00:00 2001
From: Benjamin Renard <brenard@easter-eggs.com>
Date: Fri, 6 Jan 2023 18:18:55 +0100
Subject: [PATCH] config: split console logging between stdout & stderr base on
 level

---
 mylib/config.py      | 22 +++++++++++++++++++---
 tests/test_config.py | 18 +++++++++++++++++-
 2 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/mylib/config.py b/mylib/config.py
index a6ab0de..ea3952b 100644
--- a/mylib/config.py
+++ b/mylib/config.py
@@ -879,11 +879,20 @@ class Config:  # pylint: disable=too-many-instance-attributes
             logging.getLogger().setLevel(logging.INFO)
 
         if self.get('console', 'enabled'):
-            console_handler = logging.StreamHandler(sys.stdout)
+            stdout_console_handler = logging.StreamHandler(sys.stdout)
+            stdout_console_handler.addFilter(StdoutInfoFilter())
+            stdout_console_handler.setLevel(logging.DEBUG)
+
+            stderr_console_handler = logging.StreamHandler(sys.stderr)
+            stderr_console_handler.setLevel(logging.WARNING)
+
             if self.get('console', 'log_format'):
                 console_formater = logging.Formatter(self.get('console', 'log_format'))
-                console_handler.setFormatter(console_formater)
-            logging.getLogger().addHandler(console_handler)
+                stdout_console_handler.setFormatter(console_formater)
+                stderr_console_handler.setFormatter(console_formater)
+
+            logging.getLogger().addHandler(stdout_console_handler)
+            logging.getLogger().addHandler(stderr_console_handler)
 
         if execute_callback:
             self._loaded()
@@ -1127,3 +1136,10 @@ class ConfigSectionAsDictWrapper:
 
     def __delitem__(self, key):
         raise Exception('Deleting a configuration option is not supported')
+
+
+# pylint: disable=too-few-public-methods
+class StdoutInfoFilter(logging.Filter):
+    """ Logging filter to keep messages only >= logging.INFO """
+    def filter(self, record):
+        return record.levelno in (logging.DEBUG, logging.INFO)
diff --git a/tests/test_config.py b/tests/test_config.py
index 44ab445..4018f7b 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -1,10 +1,12 @@
 # pylint: disable=redefined-outer-name,missing-function-docstring,protected-access,global-statement
 """ Tests on config lib """
 
+import logging
+
 from mylib.config import Config, ConfigSection
 from mylib.config import StringOption
 
-runned = dict()
+runned = {}
 
 
 def test_config_init_default_args():
@@ -208,3 +210,17 @@ def test_get_default():
     config.parse_arguments_options(argv=[], create=False)
 
     assert config.get(section_name, opt_name) == opt_default_value
+
+
+def test_logging_splited_stdout_stderr(capsys):
+    config = Config('Test app')
+    config.parse_arguments_options(argv=['-C', '-v'], create=False)
+    info_msg = "[info]"
+    err_msg = "[error]"
+    logging.getLogger().info(info_msg)
+    logging.getLogger().error(err_msg)
+    captured = capsys.readouterr()
+    assert info_msg in captured.out
+    assert info_msg not in captured.err
+    assert err_msg in captured.err
+    assert err_msg not in captured.out