Decrease verbosity of conda-docker

conda_docker/cli.py

@@ -22,7 +22,7 @@ def cli(args):
         sys.exit(1)
 
     args = parser.parse_args(args)
-    init_logging()
+    init_logging(args.debug)
     args.func(args)
 
 
@@ -55,6 +55,11 @@ def init_subcommand_build(subparser):
     parser.add_argument(
         "-o", "--output", type=str, help="filename for docker image", required=True
     )
+    parser.add_argument(
+        "--debug",
+        action="store_true",
+        help="Enable debug logging",
+    )
     parser.add_argument(
         "-s",
         "--solver",

conda_docker/conda.py

@@ -301,9 +301,9 @@ def fetch_precs(download_dir, precs):
             os.path.isfile(package_tarball_full_path)
             and md5_files([package_tarball_full_path]) == prec.md5
         ):
-            LOGGER.info(f"already have: {prec.fn}")
+            LOGGER.debug(f"already have: {prec.fn}")
         else:
-            LOGGER.info(f"fetching: {prec.fn}")
+            LOGGER.debug(f"fetching: {prec.fn}")
             download(prec.url, os.path.join(download_dir, prec.fn))
 
         if not os.path.isdir(extracted_package_dir):
@@ -465,7 +465,9 @@ def chroot_install(
             "--prefix",
             host_conda_opt,
             "--extract-conda-pkgs",
-        ]
+        ],
+        stdout=subprocess.DEVNULL,
+        stderr=subprocess.DEVNULL,
     )
     # now install packages in chroot
     env = dict(os.environ)
@@ -492,6 +494,8 @@ def chroot_install(
         ],
         env=env,
         cwd=host_conda_opt,
+        stdout=subprocess.DEVNULL,
+        stderr=subprocess.DEVNULL,
     )
 
     # clean up hard links
@@ -593,6 +597,8 @@ def add_conda_layers(
     else:
         raise ValueError(f"layering strategy not recognized: {layering_strategy}")
 
+    LOGGER.info(f"docker image {image.name}:{image.tag} has {len(image.layers)} layers")
+
 
 def build_docker_environment(
     base_image,

conda_docker/logging.py

@@ -1,5 +1,5 @@
 import logging
 
 
-def init_logging(level=logging.INFO):
-    logging.basicConfig(level=level)
+def init_logging(debug: bool = False):
+    logging.basicConfig(level=logging.DEBUG if debug else logging.INFO)