Shorten logging when reading meta indicators

pyam/core.py

@@ -69,7 +69,7 @@
     append_index_col,
 )
 from pyam.time import swap_time_for_year, swap_year_for_time
-from pyam.logging import raise_data_error, deprecation_warning
+from pyam.logging import raise_data_error, deprecation_warning, format_log_message
 from pyam.validation import _exclude_on_fail
 
 logger = logging.getLogger(__name__)
@@ -160,7 +160,6 @@ def _init(self, data, meta=None, index=DEFAULT_META_INDEX, **kwargs):
 
         # read from file
         if isinstance(data, Path):
-            data = Path(data)  # casting str or LocalPath to Path
             if not data.is_file():
                 raise FileNotFoundError(f"No such file: '{data}'")
             logger.info(f"Reading file {data}")
@@ -2488,9 +2487,7 @@ def to_datapackage(self, path):
         # return the package (needs to reloaded because `tmp` was deleted)
         return Package(path)
 
-    def load_meta(
-        self, path, sheet_name="meta", ignore_conflict=False, *args, **kwargs
-    ):
+    def load_meta(self, path, sheet_name="meta", ignore_conflict=False, **kwargs):
         """Load 'meta' indicators from file
 
         Parameters
@@ -2510,39 +2507,37 @@ def load_meta(
         path = path if isinstance(path, pd.ExcelFile) else Path(path)
         meta = read_pandas(path, sheet_name=sheet_name, **kwargs)
 
-        # cast model-scenario column headers to lower-case (if necessary)
+        # cast index-column headers to lower-case, check that required index exists
         meta = meta.rename(columns=dict([(i.capitalize(), i) for i in META_IDX]))
-
-        # check that required index columns exist
-        missing_cols = [c for c in self.index.names if c not in meta.columns]
-        if missing_cols:
+        if missing_cols := [c for c in self.index.names if c not in meta.columns]:
             raise ValueError(
                 f"Missing index columns for meta indicators: {missing_cols}"
             )
 
-        # set index, filter to relevant scenarios from imported file
-        n = len(meta)
+        # skip import of meta indicators if no rows in meta
+        if not len(meta.index):
+            logger.warning(f"No scenarios found in sheet {sheet_name}")
+            return
+
+        # set index, check consistency between existing index and meta
         meta.set_index(self.index.names, inplace=True)
-        meta = meta.loc[self.meta.index.intersection(meta.index)]
 
-        # skip import of meta indicators if np
-        if not n:
-            logger.info(f"No scenarios found in sheet {sheet_name}")
-            return
+        missing = self.index.difference(meta.index)
+        invalid = meta.index.difference(self.index)
 
-        msg = "Reading meta indicators"
-        # indicate if not all scenarios are included in the meta file
-        if len(meta) < len(self.meta):
-            i = len(self.meta)
-            msg += f" for {len(meta)} out of {i} scenario{s(i)}"
-
-        # indicate if more scenarios exist in meta file than in self
-        invalid = n - len(meta)
-        if invalid:
-            msg += f", ignoring {invalid} scenario{s(invalid)} from file"
-            logger.warning(msg)
-        else:
-            logger.info(msg)
+        if not missing.empty:
+            logger.warning(
+                format_log_message(
+                    "No meta indicators for the following scenarios", missing
+                )
+            )
+        if not invalid.empty:
+            logger.warning(
+                format_log_message(
+                    "Ignoring meta indicators for the following scenarios", invalid
+                )
+            )
+            meta = meta.loc[self.meta.index.intersection(meta.index)]
 
         # in pyam < 2.0, an "exclude" columns was part of the `meta` attribute
         # this section ensures compatibility with xlsx files created with pyam < 2.0

pyam/logging.py

@@ -27,9 +27,13 @@ def deprecation_warning(msg, item="This method", stacklevel=3):
 
 
 def raise_data_error(msg, data):
-    """Utils function to format error message from data formatting"""
+    """Format error message with (head of) data table and raise"""
+    raise ValueError(format_log_message(msg, data))
+
+
+def format_log_message(msg, data):
+    """Utils function to format message with (head of) data table"""
     if isinstance(data, pd.MultiIndex):
         data = data.to_frame(index=False)
     data = data.drop_duplicates()
-    msg = f"{msg}:\n{data.head()}" + ("\n..." if len(data) > 5 else "")
-    raise ValueError(msg)
+    return f"{msg}:\n{data.head()}" + ("\n..." if len(data) > 5 else "")