feat: apply new strategy to determine the home dir path;

tsdb/database.py

@@ -14,18 +14,29 @@
 tsdb_config_path = os.path.join(os.path.dirname(__file__), "config.ini")
 config.read(tsdb_config_path)
 
-old_cached_dataset_dir = os.path.join(os.path.expanduser("~"), ".tsdb_cached_datasets")
-CACHED_DATASET_DIR = os.path.join(
-    os.path.expanduser("~"), config.get("path", "data_home")
-)
+data_home_path = os.path.abspath(config.get("path", "data_home"))
+old_cached_dataset_dir = os.path.abspath("~/.tsdb_cached_datasets")
+
 if os.path.exists(old_cached_dataset_dir):
+    # use the old path and warn the user
     logger.warning(
         "‼️ Detected the home dir of the old version TSDB. "
         "Since v0.3, TSDB has changed the default cache dir to '~/.tsdb'. "
         "You can migrate downloaded datasets by invoking the new function "
-        f"tsdb.migrate(old='~/.tsdb_cached_datasets', new={CACHED_DATASET_DIR})"
+        "tsdb.migrate(old='~/.tsdb_cached_datasets', new='~/.tsdb')"
     )
     CACHED_DATASET_DIR = old_cached_dataset_dir
+elif os.path.exists(data_home_path):
+    # use the path directly, may be in a portable disk
+    CACHED_DATASET_DIR = data_home_path
+else:
+    # use the default path
+    default_path = os.path.abspath("~/.tsdb")
+    CACHED_DATASET_DIR = default_path
+    logger.warning(
+        f"‼️ The preset data_home path '{data_home_path}' doesn't exist. "
+        f"Using the default path '{default_path}'."
+    )
 
 
 _DATABASE = {