SIENTIAPDE-1579: Switched from replace logic to validation + mapping

model_manager/sientia/models.py

@@ -17,14 +17,35 @@ NORMALIZATION = 'Normalization'
 FEATURE_CREATION = 'Feature Creation'
 LAG_CREATION = 'Lag Creation'
 
+# Allowed frontend date formats and their strftime equivalents (single source of truth)
+FRONTEND_DATE_FORMAT_TO_STRFTIME = {
+    'dd/MM/yyyy HH:mm:ss': '%d/%m/%Y %H:%M:%S',
+    'MM/dd/yyyy HH:mm:ss': '%m/%d/%Y %H:%M:%S',
+    'yyyy/MM/dd HH:mm:ss': '%Y/%m/%d %H:%M:%S',
+    'dd-MM-yyyy HH:mm:ss': '%d-%m-%Y %H:%M:%S',
+    'MM-dd-yyyy HH:mm:ss': '%m-%d-%Y %H:%M:%S',
+    'yyyy-MM-dd HH:mm:ss': '%Y-%m-%d %H:%M:%S',
+}
+ALLOWED_FRONTEND_DATE_FORMATS = frozenset(FRONTEND_DATE_FORMAT_TO_STRFTIME.keys())
+
+
+def validate_frontend_date_format(fmt: str | None) -> None:
+    """Raise ValueError if fmt is set and not one of the allowed frontend date formats."""
+    if not fmt or not fmt.strip():
+        return
+    if fmt not in ALLOWED_FRONTEND_DATE_FORMATS:
+        allowed = ', '.join(sorted(ALLOWED_FRONTEND_DATE_FORMATS))
+        raise ValueError(
+            f'Invalid date_format "{fmt}". Allowed formats: {allowed}'
+        )
+
 
 def _frontend_date_format_to_strftime(fmt: str | None) -> str | None:
-    """Convert front-end date format (e.g. dd/MM/yyyy HH:mm:ss) to Python strftime."""
+    """Convert front-end date format to Python strftime. Validates format; returns None for empty."""
     if not fmt:
         return None
-    out = fmt.replace('yyyy', '%Y').replace('MM', '%m').replace('dd', '%d')
-    out = out.replace('HH', '%H').replace('mm', '%M').replace('ss', '%S')
-    return out
+    validate_frontend_date_format(fmt)
+    return FRONTEND_DATE_FORMAT_TO_STRFTIME[fmt]
 
 
 class LinearRegressionModel(BaseEstimator, TransformerMixin):

model_manager/utils/models/train_model_params.py

@@ -1,6 +1,8 @@
 from dataclasses import dataclass
 from typing import Any
 
+from model_manager.sientia.models import validate_frontend_date_format
+
 # Model name constants
 MODEL_LINEAR_REGRESSION = 'Linear Regression'
 MODEL_POLYNOMIAL_REGRESSION = 'Polynomial Regression'
@@ -217,6 +219,7 @@ class TrainModelParams:
         self._validate_intervals_and_dates()
         self._validate_limits()
         self._validate_required_strings()
+        self._validate_date_format()
 
     def _validate_numeric_ranges(self) -> None:
         """Validate numeric parameters are within acceptable ranges."""
@@ -327,3 +330,8 @@ class TrainModelParams:
 
         if not self.experiment_name.strip():
             raise ValueError('experiment_name cannot be empty or whitespace')
+
+    def _validate_date_format(self) -> None:
+        """Validate date_format is one of the allowed frontend formats when set."""
+        if self.date_format:
+            validate_frontend_date_format(self.date_format)

tests/sientia/test_models.py

@@ -7,34 +7,56 @@ import pandas as pd
 from pytest import raises
 
 from model_manager.sientia.models import (
+    ALLOWED_FRONTEND_DATE_FORMATS,
+    FRONTEND_DATE_FORMAT_TO_STRFTIME,
     DataPreprocessor,
     LinearRegressionModel,
     _frontend_date_format_to_strftime,
+    validate_frontend_date_format,
 )
 
 
 class TestFrontendDateFormatToStrftime:
     """Tests for _frontend_date_format_to_strftime (models module)."""
 
-    def test_none_or_empty_returns_none_or_empty(self):
-        """None or empty string returns None or falsy."""
+    def test_none_or_empty_returns_none(self):
+        """None or empty string returns None."""
         assert _frontend_date_format_to_strftime(None) is None
         assert _frontend_date_format_to_strftime('') is None
 
-    def test_dd_mm_yyyy_hh_mm_ss(self):
-        """Converts dd/MM/yyyy HH:mm:ss to strftime."""
-        result = _frontend_date_format_to_strftime('dd/MM/yyyy HH:mm:ss')
-        assert result == '%d/%m/%Y %H:%M:%S'
+    def test_all_six_allowed_formats_convert_correctly(self):
+        """All allowed frontend formats map to expected strftime."""
+        for frontend_fmt, strftime_fmt in FRONTEND_DATE_FORMAT_TO_STRFTIME.items():
+            assert _frontend_date_format_to_strftime(frontend_fmt) == strftime_fmt
 
-    def test_yyyy_mm_dd(self):
-        """Converts yyyy-MM-dd to strftime."""
-        result = _frontend_date_format_to_strftime('yyyy-MM-dd')
-        assert result == '%Y-%m-%d'
+    def test_invalid_format_raises(self):
+        """Invalid format raises ValueError with allowed list in message."""
+        with raises(ValueError, match='Invalid date_format'):
+            _frontend_date_format_to_strftime('yyyy-MM-dd')
+        with raises(ValueError, match='Allowed formats'):
+            _frontend_date_format_to_strftime('invalid')
 
-    def test_iso_datetime(self):
-        """Converts yyyy-MM-dd HH:mm:ss to strftime."""
-        result = _frontend_date_format_to_strftime('yyyy-MM-dd HH:mm:ss')
-        assert result == '%Y-%m-%d %H:%M:%S'
+
+class TestValidateFrontendDateFormat:
+    """Tests for validate_frontend_date_format."""
+
+    def test_none_or_empty_does_not_raise(self):
+        """None or empty string does not raise."""
+        validate_frontend_date_format(None)
+        validate_frontend_date_format('')
+        validate_frontend_date_format('   ')
+
+    def test_allowed_formats_do_not_raise(self):
+        """All allowed formats pass validation."""
+        for fmt in ALLOWED_FRONTEND_DATE_FORMATS:
+            validate_frontend_date_format(fmt)
+
+    def test_invalid_format_raises(self):
+        """Invalid format raises ValueError."""
+        with raises(ValueError, match='Invalid date_format'):
+            validate_frontend_date_format('yyyy-MM-dd')
+        with raises(ValueError, match='Invalid date_format'):
+            validate_frontend_date_format('custom-bad-format')
 
 
 class _IterableWithContains:

tests/utils/models/test_train_model_params.py

@@ -555,6 +555,27 @@ def test_validate_business_rules_valid_start_and_end_date(valid_train_params_dic
     params.validate_business_rules()  # Should not raise
 
 
+def test_validate_business_rules_invalid_date_format(valid_train_params_dict):
+    """Test validate_business_rules raises when date_format is not allowed."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+    params.date_format = 'yyyy-MM-dd'
+
+    with pytest.raises(ValueError, match='Invalid date_format'):
+        params.validate_business_rules()
+
+
+def test_validate_business_rules_valid_date_format(valid_train_params_dict):
+    """Test validate_business_rules accepts allowed date_format."""
+    from model_manager.utils.models.train_model_params import TrainModelParams
+
+    params = TrainModelParams.from_dict(valid_train_params_dict)
+    params.date_format = 'yyyy-MM-dd HH:mm:ss'
+
+    params.validate_business_rules()  # Should not raise
+
+
 def test_validate_business_rules_polynomial_regression_valid(valid_train_params_dict):
     """Test validate_business_rules accepts valid Polynomial Regression config."""
     from model_manager.utils.models.train_model_params import TrainModelParams

tests/utils/repository/test_training_repository.py

@@ -1125,27 +1125,23 @@ class TestExtractModelEquationPolynomial:
 
 
 class TestFrontendFormatToStrftime:
-    """Tests for _frontend_format_to_strftime."""
+    """Tests for _frontend_format_to_strftime (alias from models)."""
 
     def test_empty_or_none_returns_none(self):
         """Empty string or None returns None (same behavior as models module)."""
         assert _frontend_format_to_strftime('') is None
         assert _frontend_format_to_strftime(None) is None
 
-    def test_dd_mm_yyyy_hh_mm_ss(self):
-        """Converts dd/MM/yyyy HH:mm:ss to strftime."""
-        result = _frontend_format_to_strftime('dd/MM/yyyy HH:mm:ss')
-        assert result == '%d/%m/%Y %H:%M:%S'
+    def test_allowed_formats_convert_correctly(self):
+        """Allowed frontend formats convert to strftime via mapper."""
+        assert _frontend_format_to_strftime('dd/MM/yyyy HH:mm:ss') == '%d/%m/%Y %H:%M:%S'
+        assert _frontend_format_to_strftime('yyyy-MM-dd HH:mm:ss') == '%Y-%m-%d %H:%M:%S'
+        assert _frontend_format_to_strftime('MM/dd/yyyy HH:mm:ss') == '%m/%d/%Y %H:%M:%S'
 
-    def test_yyyy_mm_dd(self):
-        """Converts yyyy-MM-dd to strftime."""
-        result = _frontend_format_to_strftime('yyyy-MM-dd')
-        assert result == '%Y-%m-%d'
-
-    def test_iso_like_datetime(self):
-        """Converts yyyy-MM-dd HH:mm:ss to strftime."""
-        result = _frontend_format_to_strftime('yyyy-MM-dd HH:mm:ss')
-        assert result == '%Y-%m-%d %H:%M:%S'
+    def test_invalid_format_raises(self):
+        """Invalid date format raises ValueError."""
+        with pytest.raises(ValueError, match='Invalid date_format'):
+            _frontend_format_to_strftime('yyyy-MM-dd')
 
 
 class TestEnsureDateColumnParsed:
@@ -1215,8 +1211,11 @@ class TestEnsureDateColumnParsed:
 
     def test_invalid_values_coerced_to_nat(self, date_params):
         """Invalid date strings are coerced to NaT when format is set."""
-        date_params.date_format = 'yyyy-MM-dd'
-        data = pd.DataFrame({'ts': ['2023-01-01', 'not-a-date', '2023-12-31'], 'x': [1, 2, 3]})
+        date_params.date_format = 'yyyy-MM-dd HH:mm:ss'
+        data = pd.DataFrame({
+            'ts': ['2023-01-01 00:00:00', 'not-a-date', '2023-12-31 00:00:00'],
+            'x': [1, 2, 3],
+        })
         result = _ensure_date_column_parsed(data, date_params)
         assert pd.isna(result['ts'].iloc[1])
         assert result['ts'].iloc[0].year == 2023