quite a bit of development around get rates input handling

xexe/cli.py

@@ -74,7 +74,7 @@ def get_rates(
     dry_run: bool,
     output: pathlib.Path,
 ):
-    handle_get_rates_inputs(
+    inputs = handle_get_rates_inputs(
         start_date=start_date,
         end_date=end_date,
         currencies=currencies,

xexe/constants.py

@@ -1,6 +1,10 @@
 import pathlib
 from dataclasses import dataclass
 
+from currencies import Currency
+
+DEFAULT_CURRENCIES = {Currency("EUR"), Currency("GBP"), Currency("USD")}
+
 
 @dataclass
 class PATHS:

xexe/inputs_handling.py

@@ -1,12 +1,51 @@
+import datetime
 import logging
+import pathlib
+from typing import Union
+
+from currencies import Currency
+
+from xexe.constants import DEFAULT_CURRENCIES
+from xexe.utils import DateRange
 
 logger = logging.getLogger()
 
 
-def handle_get_rates_inputs(start_date, end_date, currencies, dry_run, output):
+def handle_get_rates_inputs(
+    start_date: Union[datetime.datetime, datetime.date],
+    end_date: Union[datetime.datetime, datetime.date],
+    currencies: Union[None, str],
+    dry_run: bool,
+    output: Union[str, pathlib.Path],
+):
     logger.info("Handling inputs.")
-    logger.debug(f"Received start_date: {start_date}")
-    logger.debug(f"Received end_date: {end_date}")
-    logger.debug(f"Received currencies: {currencies}")
-    logger.debug(f"dry_run state: {dry_run}")
-    logger.debug(f"Received output: {output}")
+
+    date_range = DateRange(start_date=start_date.date(), end_date=end_date.date())
+
+    if date_range.end_date > datetime.datetime.today().date():
+        date_range.end_date = datetime.datetime.today().date()
+
+    if currencies:
+        # CLI input comes as string of comma-separated currency codes
+        currencies = [currency_code.strip() for currency_code in currencies.split(",")]
+        tmp = [Currency(currency_code) for currency_code in currencies]
+        currencies = tmp
+
+    if currencies is None:
+        currencies = DEFAULT_CURRENCIES
+
+    # The Path constructor is idempotent, so this works equally fine if output
+    # is a string or an actual Path object.
+    output = pathlib.Path(output)
+    if output.suffix != ".csv":
+        raise ValueError("Output must be a .csv file.")
+
+    prepared_inputs = {
+        "date_range": date_range,
+        "currencies": currencies,
+        "dry_run": dry_run,
+        "output": output,
+    }
+
+    logger.debug(prepared_inputs)
+    return prepared_inputs

xexe/utils.py

@@ -0,0 +1,42 @@
+import datetime
+
+
+class DateRange:
+
+    def __init__(self, start_date: datetime.date, end_date: datetime.date):
+        if type(start_date) != datetime.date or type(end_date) != datetime.date:
+            raise TypeError("start_date and end_date must be date objects.")
+
+        if start_date > end_date:
+            raise ValueError("start_date can't be after end_date.")
+
+        self._start_date = start_date
+        self._end_date = end_date
+
+    @property
+    def start_date(self):
+        return self._start_date
+
+    @start_date.setter
+    def start_date(self, value: datetime.date):
+        if type(value) != datetime.date:
+            raise TypeError("start_date must be a date object.")
+
+        if value > self._end_date:
+            raise ValueError("start_date can't be after end_date.")
+
+        self._start_date = value
+
+    @property
+    def end_date(self):
+        return self._end_date
+
+    @end_date.setter
+    def end_date(self, value: datetime.date):
+        if type(value) != datetime.date:
+            raise TypeError("end_date must be a date object.")
+
+        if value < self._start_date:
+            raise ValueError("end_date can't be before start_date.")
+
+        self._end_date = value