feat: set log level for all craft libs

craft_application/application.py

@@ -18,6 +18,7 @@
 
 import functools
 import importlib
+import logging
 import os
 import pathlib
 import signal
@@ -244,6 +245,14 @@ def _get_dispatcher(self) -> craft_cli.Dispatcher:
 
         :returns: A ready-to-run Dispatcher object
         """
+        # Set the logging level to DEBUG for all craft-libraries. This is OK even if
+        # the specific application doesn't use a specific library, the call does not
+        # import the package.
+        craft_libs = ["craft_archives", "craft_parts", "craft_providers", "craft_store"]
+        for craft_lib in craft_libs:
+            logger = logging.getLogger(craft_lib)
+            logger.setLevel(logging.DEBUG)
+
         craft_cli.emit.init(
             mode=craft_cli.EmitterMode.BRIEF,
             appname=self.app.name,

tests/unit/test_application.py

@@ -17,6 +17,7 @@
 import argparse
 import importlib
 import importlib.metadata
+import logging
 import pathlib
 import re
 import subprocess
@@ -298,6 +299,23 @@ def test_get_dispatcher_error(
     check.is_true(re.fullmatch(message, captured.err), captured.err)
 
 
+def test_craft_lib_log_level(app):
+    craft_libs = ["craft_archives", "craft_parts", "craft_providers", "craft_store"]
+
+    # The logging module is stateful and global, so first lets clear the logging level
+    # that another test might have already set.
+    for craft_lib in craft_libs:
+        logger = logging.getLogger(craft_lib)
+        logger.setLevel(logging.NOTSET)
+
+    with pytest.raises(SystemExit):
+        app._get_dispatcher()
+
+    for craft_lib in craft_libs:
+        logger = logging.getLogger(craft_lib)
+        assert logger.level == logging.DEBUG
+
+
 @pytest.mark.parametrize(
     "argv",
     [["testcraft", "--version"], ["testcraft", "-V"], ["testcraft", "pull", "-V"]],