Refactor codebase for improved readability and maintainability

src/bonbast/helpers/click_callbacks.py

@@ -9,9 +9,8 @@
 def print_version(ctx, param, value):
     if not value or ctx.resilient_parsing:
         return
-    else:
-        click.echo(bonbast_version)
-        ctx.exit()
+    click.echo(bonbast_version)
+    ctx.exit()
 
 
 def parse_show_only(ctx, param, value):

src/bonbast/helpers/utils.py

@@ -10,10 +10,10 @@
 class Singleton(type):
     _instances = {}
 
-    def __call__(cls, *args, **kwargs):
-        if cls not in cls._instances:
-            cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
-        return cls._instances[cls]
+    def __call__(self, *args, **kwargs):
+        if self not in self._instances:
+            self._instances[self] = super(Singleton, self).__call__(*args, **kwargs)
+        return self._instances[self]
 
 
 def format_toman(price: float) -> str:
@@ -37,9 +37,11 @@ def wrapper_retry(*args, **kwargs):
             for i in range(retry_count):
                 try:
                     return func(*args, **kwargs)
+
                 except RetryError as e:
                     if i == retry_count - 1:
                         raise SystemExit(e.message)
+
                 except Exception as e:  # noqa
                     if retry_delay is not None:
                         time.sleep(retry_delay)

src/bonbast/main.py

@@ -28,10 +28,11 @@ def get_prices(show_only: List[str] = None):
     token = token_manager.generate()
     try:
         response = get_prices_from_api(token.value)
-        if show_only is not None and len(show_only) > 0:
+        if show_only:
             response = list(response)
             for index, item in enumerate(response):
-                response[index] = [item for item in item if item.code.lower() in show_only]
+                response[index] = [
+                    item for item in item if item.code.lower() in show_only]
             response = tuple(response)
 
         return response
@@ -76,7 +77,6 @@ def cli(ctx, show_only):
 def live(ctx):
     if ctx.invoked_subcommand is None:
         print('Show full table with live prices / up and down arrows')
-    pass
 
 
 # ================ bonbast live graph ================
@@ -101,7 +101,8 @@ def live_simple(interval, show_only):
             collections = get_prices(show_only)
 
             prices_text = Text()
-            prices_text.append(f'{datetime.now().strftime("%Y-%m-%d %H:%M:%S")}\n\n', style='bold')
+            prices_text.append(
+                f'{datetime.now().strftime("%Y-%m-%d %H:%M:%S")}\n\n', style='bold')
 
             for collection_index, collection in enumerate(collections):
                 for index, model in enumerate(collection):
@@ -160,28 +161,35 @@ def live_currency(interval, currency):
             # add a row with the new information
             if type(item) is Currency or type(item) is Coin:
                 sell_symbol = f' {get_change_char(item.sell, old_model.sell)}' if old_model is not None else ''
-                sell_str = (item.formatted_sell if item.sell is not None else '-') + sell_symbol
-                sell_color = get_color(item.sell, None if old_model is None else old_model.sell)
+                sell_str = (
+                    item.formatted_sell if item.sell is not None else '-') + sell_symbol
+                sell_color = get_color(
+                    item.sell, None if old_model is None else old_model.sell)
 
                 buy_symbol = f' {get_change_char(item.buy, old_model.buy)}' if old_model is not None else ''
-                buy_str = (item.formatted_buy if item.buy is not None else '-') + buy_symbol
-                buy_color = get_color(item.buy, None if old_model is None else old_model.buy)
+                buy_str = (
+                    item.formatted_buy if item.buy is not None else '-') + buy_symbol
+                buy_color = get_color(
+                    item.buy, None if old_model is None else old_model.buy)
 
                 price = (
                     Text(sell_str, style=sell_color),
                     Text(buy_str, style=buy_color),
                 )
             else:
                 price_char = f' {get_change_char(item.price, old_model.price)}' if old_model is not None else ''
-                price_str = (item.formatted_price if item.price is not None else '-') + price_char
-                price_color = get_color(item.price, None if old_model is None else old_model.price)
+                price_str = (
+                    item.formatted_price if item.price is not None else '-') + price_char
+                price_color = get_color(
+                    item.price, None if old_model is None else old_model.price)
 
                 price = (
                     Text(price_str, style=price_color),
                 )
 
             table.add_row(
-                Text(datetime.now().strftime("%Y-%m-%d %H:%M:%S"), style=DEFAULT_TEXT_COLOR),
+                Text(datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
+                     style=DEFAULT_TEXT_COLOR),
                 Text(item.name, style=DEFAULT_TEXT_COLOR),
                 *price,
             )
@@ -201,21 +209,26 @@ def live_currency(interval, currency):
 @click.pass_context
 def convert(ctx, source, destination, amount, only_buy, only_sell):
     if source is None and destination is None:
-        raise click.BadOptionUsage('', 'Please specify source or destination currency')
+        raise click.BadOptionUsage(
+            '', 'Please specify source or destination currency')
 
     if source is not None and destination is not None:
-        raise click.BadOptionUsage('', 'Don\'t use --source and --destination together')
+        raise click.BadOptionUsage(
+            '', 'Don\'t use --source and --destination together')
 
     if only_buy and only_sell:
-        raise click.BadOptionUsage('', 'Don\'t use --only-buy and --only-sell together')
+        raise click.BadOptionUsage(
+            '', 'Don\'t use --only-buy and --only-sell together')
 
     currencies_list, _, __ = get_prices()
     if source is not None:
-        currency = next(currency for currency in currencies_list if currency.code.lower() == source.lower())
+        currency = next(
+            currency for currency in currencies_list if currency.code.lower() == source.lower())
         buy = format_toman(int(amount * currency.buy))
         sell = format_toman(int(amount * currency.sell))
     else:
-        currency = next(currency for currency in currencies_list if currency.code.lower() == destination.lower())
+        currency = next(currency for currency in currencies_list if currency.code.lower(
+        ) == destination.lower())
         buy = format_price(amount / currency.sell)
         sell = format_price(amount / currency.buy)
 

src/bonbast/managers/storage_manager.py

@@ -1,3 +1,4 @@
+import contextlib
 import os
 import pathlib
 import sys
@@ -56,7 +57,5 @@ def load_file(self) -> str:
     def delete_file(self) -> None:
         """ Delete the saved token from datadir
         """
-        try:
+        with contextlib.suppress(FileNotFoundError):
             os.remove(self.file_path)
-        except FileNotFoundError:
-            pass

src/bonbast/server.py

@@ -52,16 +52,18 @@ def get_token_from_main_page():
     try:
         r = requests.get(BASE_URL, headers=headers)
         r.raise_for_status()
+
     except requests.exceptions.HTTPError as err:
         raise SystemExit(err)
+
     except requests.exceptions.ConnectionError as _:
         raise SystemExit('Error: Failed to connect to bonbast')
 
     search = re.search(r"param\s*=\s*\"(.+)\"", r.text, re.MULTILINE)
     if search is None or search.group(1) is None:
         raise SystemExit('Error: token not found in the main page')
 
-    return search.group(1)
+    return search[1]
 
 
 def get_prices_from_api(token: str) -> Tuple[List[Currency], List[Coin], List[Gold]]:
@@ -107,44 +109,38 @@ def get_prices_from_api(token: str) -> Tuple[List[Currency], List[Coin], List[Go
     if 'reset' in r:
         raise ResetAPIError('Error: token is expired')
 
-    currencies: List[Currency] = []
-    coins: List[Coin] = []
-    golds: List[Gold] = []
-
-    for currency in Currency.VALUES:
-        if f'{currency}{BUY}' in r and f'{currency}{SELL}' in r:
-            currencies.append(Currency(
-                currency.upper(),
-                Currency.VALUES[currency],
-                sell=int(r[f'{currency}{SELL}']),
-                buy=int(r[f'{currency}{BUY}']),
-            ))
-
-    for coin in Coin.VALUES:
-        if f'{coin}' in r and f'{coin}{BUY}' in r:
-            coins.append(Coin(
-                coin,
-                Coin.VALUES[coin],
-                sell=int(r[coin]),
-                buy=int(r[f'{coin}{BUY}']),
-            ))
-
-    for gold in Gold.VALUES:
-        if f'{gold}' in r:
-            golds.append(Gold(
-                gold,
-                Gold.VALUES[gold],
-                price=int(r[gold])
-            ))
+    coins: List[Coin] = [
+        Coin(
+            coin,
+            Coin.VALUES[coin],
+            sell=int(r[coin]),
+            buy=int(r[f'{coin}{BUY}']),
+        )
+        for coin in Coin.VALUES
+        if f'{coin}' in r and f'{coin}{BUY}' in r
+    ]
+
+    golds: List[Gold] = [
+        Gold(gold, Gold.VALUES[gold], price=int(r[gold]))
+        for gold in Gold.VALUES
+        if f'{gold}' in r
+    ]
+
+    currencies: List[Currency] = [
+        Currency(
+            currency.upper(),
+            Currency.VALUES[currency],
+            sell=int(r[f'{currency}{SELL}']),
+            buy=int(r[f'{currency}{BUY}']),
+        )
+        for currency in Currency.VALUES
+        if f'{currency}{BUY}' in r and f'{currency}{SELL}' in r
+    ]
 
     return currencies, coins, golds
 
 
-def get_graph_data(
-        currency: str,
-        start_date: datetime = datetime.today() - timedelta(days=30),
-        end_date: datetime = datetime.today(),
-) -> Dict[str, int]:
+def get_graph_data(currency: str, start_date: datetime = datetime.now() - timedelta(days=30), end_date: datetime = datetime.now()) -> Dict[str, int]:
     """
         This function will make a request to bonbast.com/graph and make them in two array.
     """
@@ -168,36 +164,45 @@ def get_graph_data(
     }
 
     try:
-        request = requests.get(f'{BASE_URL}/graph/{currency}/{start_date.date()}/{end_date.date()}', headers=headers)
+        request = requests.get(
+            f'{BASE_URL}/graph/{currency}/{start_date.date()}/{end_date.date()}', headers=headers)
         request.raise_for_status()
     except requests.exceptions.HTTPError as err:
-        raise SystemExit(err)
+        raise SystemExit(err) from err
 
     soup = BeautifulSoup(request.text, 'html.parser')
     for data in soup.find_all("script"):
         # get variables from script and convert them to list
         if "data: {" in data.text:
-            price_list = data.text.split("data: [")[1].split("]")[0].split(",")
-            date_list = data.text.split("labels: [")[1].split("]")[0].split(',')
+            return get_graph_data(data)
 
-            if len(price_list) != len(date_list):
-                raise SystemExit('Error: data inconsistency')
 
-            dic = {}
-            for i in range(len(price_list)):
-                price = int(price_list[i])
-                date = re.search(r'\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])', date_list[i]).group(0)
-                dic[date] = price
+def get_graph_data(data):
+    price_list = data.text.split("data: [")[1].split("]")[0].split(",")
+    date_list = data.text.split("labels: [")[1].split("]")[0].split(',')
 
-            return dic
+    if len(price_list) != len(date_list):
+        raise SystemExit('Error: data inconsistency')
+
+    dic = {}
+    for i in range(len(price_list)):
+        price = int(price_list[i])
+        date = re.search(
+            r'\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])', date_list[i]
+        )[0]
+        dic[date] = price
+
+    return dic
 
 
 def get_history(date: datetime = datetime.today() - timedelta(days=1)) -> List[Currency]:
     if date.date() < datetime(2012, 10, 9).date():
-        raise SystemExit('Error: date is too far in the past. Date must be greater than 2012-10-09')
+        raise SystemExit(
+            'Error: date is too far in the past. Date must be greater than 2012-10-09')
 
-    if date.date() >= datetime.today().date():
-        raise SystemExit(f'Error: date must be less than today({date.today().date()}).')
+    if date.date() >= datetime.now().date():
+        raise SystemExit(
+            f'Error: date must be less than today({date.today().date()}).')
 
     headers = {
         'authority': 'bonbast.com',
@@ -216,17 +221,18 @@ def get_history(date: datetime = datetime.today() - timedelta(days=1)) -> List[C
     }
 
     try:
-        request = requests.get(f'{BASE_URL}/archive/{date.strftime("%Y/%m/%d")}', headers=headers)
+        request = requests.get(
+            f'{BASE_URL}/archive/{date.strftime("%Y/%m/%d")}', headers=headers)
         request.raise_for_status()
     except requests.exceptions.HTTPError as err:
-        raise SystemExit(err)
+        raise SystemExit(err) from err
 
     soup = BeautifulSoup(request.text, 'html.parser')
     tables = soup.findAll("table")
 
     # first and second table are currencies
     currencies: List[Currency] = []
-    for table in tables[0:1]:
+    for table in tables[:1]:
         for row in table.findAll('tr')[1:]:
             cells = row.findAll("td")
             currencies.append(Currency(