New config option cm_config_log_level (#963)

* New config option `cm_config_log_level`
* Log the config file when the config contents has changed

docs/CHANGELOG.md

@@ -6,6 +6,9 @@ Jupytext ChangeLog
 
 **Changed**
 - Hidden configuration files like `.jupytext.toml` or `.jupytext.py` are now ignored by Jupytext's contents manager when `allow_hidden=False` (that option was introduced in `jupyter_server==2.0.0a1`) ([#964](https://github.com/mwouts/jupytext/issues/964)).
+- The Jupytext configuration file has a new option `cm_config_log_level` that defaults to `info_if_changed`.
+With that value, the contents manager will log a line regarding the configuration file used only when the
+config file is not the same as the one previously used ([#959](https://github.com/mwouts/jupytext/issues/959))
 
 
 1.13.8 (2022-04-04)

jupytext/config.py

@@ -143,6 +143,13 @@ class JupytextConfiguration(Configurable):
         config=True,
     )
 
+    cm_config_log_level = Enum(
+        values=["warning", "info", "info_if_changed", "debug", "none"],
+        default_value="info_if_changed",
+        help="The log level for config file logs in the Jupytext contents manager",
+        config=True,
+    )
+
     cell_markers = Unicode(
         help='Start and end cell markers for the light format, comma separated. Use "{{{,}}}" to mark cells'
         'as foldable regions in Vim, and "region,endregion" to mark cells as Vscode/PyCharm regions',
@@ -244,6 +251,13 @@ def default_formats(self, path):
 
         return None
 
+    def __eq__(self, other):
+        for key in self.class_trait_names():
+            if getattr(self, key) != getattr(other, key):
+                return False
+
+        return True
+
 
 def preferred_format(incomplete_format, preferred_formats):
     """Return the preferred format for the given extension"""

jupytext/contentsmanager.py

@@ -526,11 +526,12 @@ def get_config_file(self, directory):
             parent_dir = self.get_parent_dir(directory)
             return self.get_config_file(parent_dir)
 
-        def load_config_file(self, config_file, is_os_path=False):
+        def load_config_file(
+            self, config_file, *, prev_config_file, prev_config, is_os_path=False
+        ):
             """Load the configuration file"""
             if config_file is None:
                 return None
-            self.log.info("Loading Jupytext configuration file at %s", config_file)
             if config_file.endswith(".py") and not is_os_path:
                 config_file = self._get_os_path(config_file)
                 is_os_path = True
@@ -543,7 +544,21 @@ def load_config_file(self, config_file, is_os_path=False):
                 except HTTPError:
                     pass
 
-            return load_jupytext_configuration_file(config_file, config_content)
+            config = load_jupytext_configuration_file(config_file, config_content)
+            if config is None:
+                return config
+
+            log_level = config.cm_config_log_level
+            if log_level == "info_if_changed":
+                if config_file != prev_config_file or config != prev_config:
+                    log_level = "info"
+                else:
+                    log_level = "none"
+            if log_level != "none":
+                getattr(self.log, log_level)(
+                    "Loaded Jupytext configuration file at %s", config_file
+                )
+            return config
 
         def get_config(self, path, use_cache=False):
             """Return the Jupytext configuration for the given path"""
@@ -556,10 +571,19 @@ def get_config(self, path, use_cache=False):
                 try:
                     config_file = self.get_config_file(parent_dir)
                     if config_file:
-                        self.cached_config.config = self.load_config_file(config_file)
+                        self.cached_config.config = self.load_config_file(
+                            config_file,
+                            prev_config_file=self.cached_config.config_file,
+                            prev_config=self.cached_config.config,
+                        )
                     else:
                         config_file = find_global_jupytext_configuration_file()
-                        self.cached_config.config = self.load_config_file(config_file)
+                        self.cached_config.config = self.load_config_file(
+                            config_file,
+                            prev_config_file=self.cached_config.config_file,
+                            prev_config=self.cached_config.config,
+                            is_os_path=True,
+                        )
                     self.cached_config.config_file = config_file
                     self.cached_config.path = parent_dir
                 except JupytextConfigurationError as err:
@@ -572,11 +596,6 @@ def get_config(self, path, use_cache=False):
                     raise HTTPError(500, f"{err}")
 
             if self.cached_config.config is not None:
-                self.log.debug(
-                    "Configuration file for %s is %s",
-                    path,
-                    self.cached_config.config_file,
-                )
                 return self.cached_config.config
             if isinstance(self.notebook_extensions, str):
                 self.notebook_extensions = self.notebook_extensions.split(",")

tests/conftest.py

@@ -38,6 +38,13 @@ def cwd_tmpdir(tmpdir):
         yield tmpdir
 
 
+@pytest.fixture()
+def cwd_tmp_path(tmp_path):
+    # Run the whole test from inside tmp_path
+    with tmp_path.cwd():
+        yield tmp_path
+
+
 @pytest.fixture
 def jupytext_repo_root():
     """The local path of this repo, to use in .pre-commit-config.yaml in tests"""

tests/test_cm_config.py

@@ -1,3 +1,4 @@
+import logging
 import os
 import sys
 import unittest.mock as mock
@@ -220,3 +221,61 @@ def test_test_no_text_representation_metadata_in_ipynb_900(
     assert "text_representation" in tmpdir.join("test.py").read()
     # But not in the ipynb notebook
     assert "text_representation" not in tmpdir.join("test.ipynb").read()
+
+
+def test_cm_config_no_log(cwd_tmp_path, tmp_path, caplog):
+    cm = jupytext.TextFileContentsManager()
+    cm.root_dir = str(tmp_path)
+
+    config = 'cm_config_log_level="none"'
+    (tmp_path / "jupytext.toml").write_text(config)
+    (tmp_path / "nb1.py").write_text("# %%")
+    (tmp_path / "subfolder").mkdir()
+    (tmp_path / "subfolder" / "jupytext.toml").write_text(config)
+    (tmp_path / "subfolder" / "nb2.py").write_text("# %%")
+
+    caplog.set_level(logging.DEBUG)
+
+    cm.get("nb1.py", type="notebook", content=False)
+    cm.get("nb1.py", type="notebook", content=True)
+    cm.get("subfolder/nb2.py", type="notebook", content=False)
+    cm.get("subfolder/nb2.py", type="notebook", content=True)
+
+    assert "Jupytext configuration file" not in caplog.text
+
+
+def test_cm_config_log_only_if_changed(cwd_tmp_path, tmp_path, caplog):
+    cm = jupytext.TextFileContentsManager()
+    cm.root_dir = str(tmp_path)
+
+    config = ""
+    (tmp_path / "jupytext.toml").write_text(config)
+    (tmp_path / "nb1.py").write_text("# %%")
+    (tmp_path / "subfolder").mkdir()
+    (tmp_path / "subfolder" / "jupytext.toml").write_text(config)
+    (tmp_path / "subfolder" / "nb2.py").write_text("# %%")
+
+    caplog.set_level(logging.INFO)
+
+    cm.get("nb1.py", type="notebook", content=False)
+    assert "Jupytext configuration file" in caplog.text
+    caplog.clear()
+
+    # Same notebook, same config => no log
+    cm.get("nb1.py", type="notebook", content=True)
+    assert "Jupytext configuration file" not in caplog.text
+
+    # Same notebook, config changed => log
+    (tmp_path / "jupytext.toml").write_text('formats="ipynb,py:percent"')
+    cm.get("nb1.py", type="notebook", content=True)
+    assert "Jupytext configuration file" in caplog.text
+    caplog.clear()
+
+    # Different folder, different config
+    cm.get("subfolder/nb2.py", type="notebook", content=False)
+    assert "Jupytext configuration file" in caplog.text
+    caplog.clear()
+
+    # Same config as previously => no log
+    cm.get("subfolder/nb2.py", type="notebook", content=False)
+    assert "Jupytext configuration file" not in caplog.text