fix po dates params (#3619)

Co-authored-by: James Maslek <jmaslek11@gmail.com>
Co-authored-by: Chavithra <chavithra@gmail.com>

openbb_terminal/portfolio/portfolio_optimization/parameters/params_helpers.py

@@ -1,8 +1,10 @@
 import argparse
-from typing import Dict
+from datetime import datetime
+from typing import Dict, List
 from pathlib import Path
 from openbb_terminal.helper_funcs import log_and_raise
 from openbb_terminal.core.config import paths
+from openbb_terminal.rich_config import console
 
 
 def check_save_file(file: str) -> str:
@@ -40,3 +42,40 @@ def load_data_files() -> Dict[str, Path]:
                     data_files[filepath.name] = filepath
 
     return data_files
+
+
+def check_convert_dates(params: dict, param_name_list: List[str]) -> dict:
+    """Check if the argument is in the list and convert it to a str object
+    Parameters
+    ----------
+    params : dict
+        The parameters to be converted
+    param_name_list : List[str]
+        The list of arguments to be converted
+
+    Returns
+    -------
+    dict
+        The converted parameters
+    """
+
+    for param_name in param_name_list:
+        if param_name in params:
+            param_value = params[param_name]
+            if isinstance(param_value, datetime):
+                params[param_name] = param_value.strftime("%Y-%m-%d")
+            elif isinstance(param_value, str):
+                try:
+                    param_value = datetime.strptime(param_value, "%Y-%m-%d")
+                except ValueError:
+                    console.print(
+                        f"[red]'{param_name}' format is not a valid date, must be YYYY-MM-DD.\n[/red]"
+                    )
+                    params.pop(param_name)
+            else:
+                console.print(
+                    f"[red]'{param_name}' format is not a valid date, must be YYYY-MM-DD.\n[/red]"
+                )
+                params.pop(param_name)
+
+    return params

openbb_terminal/portfolio/portfolio_optimization/parameters/params_view.py

@@ -8,6 +8,9 @@ from openbb_terminal.helper_funcs import print_rich_table
 from openbb_terminal.portfolio.portfolio_optimization import excel_model
 from openbb_terminal.rich_config import console
 from openbb_terminal.portfolio.portfolio_optimization.parameters import params_statics
+from openbb_terminal.portfolio.portfolio_optimization.parameters.params_helpers import (
+    check_convert_dates,
+)
 from openbb_terminal.core.config import paths
 
 
@@ -41,11 +44,13 @@ def load_file(path: str = "") -> Tuple[dict, str]:
         params, _ = excel_model.load_configuration(path)
         current_model = params["technique"]
     else:
-        console.print(
-            "Can not load in the file due to not being an .ini or .xlsx file."
-        )
+        console.print("Cannot load in the file due to not being an .ini or .xlsx file.")
         return {}, ""
 
+    params = check_convert_dates(
+        params=params, param_name_list=["start_period", "end_period"]
+    )
+
     max_len = max(len(k) for k in params.keys())
     help_text = "[info]Parameters:[/info]\n"