Fix API, that gives an error if target is not specified (#196)

Author: liudmylaru

ads/dataset/dataset.py

@@ -172,7 +172,7 @@ def from_dataframe(
             progress=progress,
             transformer_pipeline=transformer_pipeline,
             interactive=interactive,
-            **kwargs
+            **kwargs,
         )
 
     @property
@@ -1913,3 +1913,43 @@ def show_in_notebook(
 
         if visualize_features and not is_wide_dataset:
             self._visualize_feature_distribution(features)
+
+    def get_recommendations(self, *args, **kwargs):  # real signature may change
+        """
+        Returns user-friendly error message to set target variable before invoking this API.
+
+        Parameters
+        ----------
+        kwargs
+
+        Returns
+        -------
+        NotImplementedError
+            raises NotImplementedError, if target parameter value not provided
+
+        """
+        raise NotImplementedError(
+            "Please set the target using set_target() before invoking this API. See "
+            "https://accelerated-data-science.readthedocs.io/en/latest/ads.dataset.html#ads.dataset.dataset.ADSDataset.set_target "
+            "for the API usage."
+        )
+
+    def suggest_recommendations(self, *args, **kwargs):  # real signature may change
+        """
+        Returns user-friendly error message to set target variable before invoking this API.
+
+        Parameters
+        ----------
+        kwargs
+
+        Returns
+        -------
+        NotImplementedError
+            raises NotImplementedError, if target parameter value not provided
+
+        """
+        raise NotImplementedError(
+            "Please set the target using set_target() before invoking this API. See "
+            "https://accelerated-data-science.readthedocs.io/en/latest/ads.dataset.html#ads.dataset.dataset.ADSDataset.set_target "
+            "for the API usage."
+        )

tests/unitary/with_extras/dataset/test_dataset_dataset.py

@@ -25,6 +25,10 @@ def setup_class(cls):
     def teardown_class(cls):
         cls.test_dir.cleanup()
 
+    def get_data_path(self):
+        current_dir = os.path.dirname(os.path.abspath(__file__))
+        return os.path.join(current_dir, "data", "orcl_attrition.csv")
+
     @pytest.mark.parametrize(
         "test_file_name, expected_file_name",
         [
@@ -93,6 +97,12 @@ def assert_dataset(self, dataset):
         assert "type_discovery" in dataset.init_kwargs
         assert isinstance(dataset.transformer_pipeline, TransformerPipeline)
 
-    def get_data_path(self):
-        current_dir = os.path.dirname(os.path.abspath(__file__))
-        return os.path.join(current_dir, "data", "orcl_attrition.csv")
+    def test_get_suggest_recommendations_error_message(self):
+        """Test for validation user-friendly error message."""
+        employees = ADSDataset.from_dataframe(df=pd.read_csv(self.get_data_path()))
+
+        err_msg = r"Please set the target using set_target\(\) before invoking this API."
+        with pytest.raises(NotImplementedError, match=err_msg):
+            employees.get_recommendations()
+        with pytest.raises(NotImplementedError, match=err_msg):
+            employees.suggest_recommendations()