cli: Don't show a traceback or warning if the config file does not exist

swh/fuse/cli.py

@@ -66,23 +66,27 @@ def fuse(ctx, config_file):
     if not config_file:
         config_file = DEFAULT_CONFIG_PATH
 
-    try:
-        conf = config.read_raw_config(config.config_basepath(config_file))
-        if not conf:
-            raise ValueError(f"Cannot parse configuration file: {config_file}")
-
-        if config_file == DEFAULT_CONFIG_PATH:
-            try:
-                conf = conf["swh"]["fuse"]
-            except KeyError:
-                pass
-
-        # recursive merge not done by config.read
-        conf = config.merge_configs(DEFAULT_CONFIG, conf)
-    except Exception:
-        logging.warning(
-            "Using default configuration (cannot load custom one)", exc_info=True
-        )
+    if os.path.isfile(config_file):
+        try:
+            conf = config.read_raw_config(config.config_basepath(config_file))
+            if not conf:
+                raise ValueError(f"Cannot parse configuration file: {config_file}")
+
+            if config_file == DEFAULT_CONFIG_PATH:
+                try:
+                    conf = conf["swh"]["fuse"]
+                except KeyError:
+                    pass
+
+            # recursive merge not done by config.read
+            conf = config.merge_configs(DEFAULT_CONFIG, conf)
+        except Exception:
+            logging.warning(
+                "Using default configuration (cannot load custom one)", exc_info=True
+            )
+            conf = DEFAULT_CONFIG
+    else:
+        logging.info("Using default configuration")
         conf = DEFAULT_CONFIG
 
     logging.debug("Read configuration: \n%s", yaml.dump(conf))