Improve read dataset function

dt-cart/backend/dataset/__init__.py

@@ -3,6 +3,7 @@ import uuid
 
 import pandas as pd
 from pandas import DataFrame
+from pandas.errors import ParserError
 from sklearn.model_selection import train_test_split
 from werkzeug import utils
 
@@ -33,10 +34,21 @@ class Dataset:
         return file_name
 
     def read(self, params: DatasetParams) -> DataFrame:
-        df = pd.read_csv(self.__file_name, sep=params.sep, decimal=params.decimal)
+        df = None
+        try:
+            df = pd.read_csv(self.__file_name, sep=params.sep, decimal=params.decimal)
+        except ParserError:
+            raise Exception(
+                "Can't parse dataset. Try to use correct 'sep' and 'decimal' values."
+            )
+        if df.columns.size < 2:
+            raise Exception(
+                "Dataset contains less than 2 columns. "
+                "Try to use correct 'sep' parameter value."
+            )
+        params.target = params.target or df.columns[-1]
         if params.input is not None:
             return df[params.input + [params.target]]
-
         return df
 
     def __split(
@@ -46,9 +58,8 @@ class Dataset:
         random_state: int,
         is_classification: bool = False,
     ) -> SplittedDataset:
-        target = params.target or data.columns[-1]
         X = data.drop([params.target], axis=1)
-        y = data[[target]]
+        y = data[[params.target]]
         stratify = None if not is_classification else y
         X_train, X_test, y_train, y_test = train_test_split(
             X,