Implement hex color conversion

gspread/utils.py

@@ -19,6 +19,7 @@
     Dict,
     Iterable,
     List,
+    Mapping,
     Optional,
     Tuple,
     TypeVar,
@@ -718,6 +719,89 @@ def combined_merge_values(worksheet_metadata, values):
     return new_values
 
 
+def convert_hex_to_colors_dict(hex_color: str) -> Mapping[str, float]:
+    """Convert a hex color code to RGB color values.
+
+    :param str hex_color: Hex color code in the format "#RRGGBB".
+
+    :returns: Dict containing the color's red, green and blue values between 0 and 1.
+    :rtype: dict
+
+    :raises:
+        ValueError: If the input hex string is not in the correct format or length.
+
+    Examples:
+        >>> convert_hex_to_colors_dict("#3300CC")
+        {'red': 0.2, 'green': 0.0, 'blue': 0.8}
+
+        >>> convert_hex_to_colors_dict("#30C")
+        {'red': 0.2, 'green': 0.0, 'blue': 0.8}
+
+    """
+    hex_color = hex_color.lstrip("#")
+
+    # Google API ColorStyle Reference:
+    # "The alpha value in the Color object isn't generally supported."
+    # https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/other#colorstyle
+    if len(hex_color) == 8:
+        hex_color = hex_color[:-2]
+
+    # Expand 3 character hex.
+    if len(hex_color) == 3:
+        hex_color = "".join([char * 2 for char in hex_color])
+
+    if len(hex_color) != 6:
+        raise ValueError("Hex color code must be in the format '#RRGGBB'.")
+
+    try:
+        rgb_color = {
+            "red": int(hex_color[0:2], 16) / 255,
+            "green": int(hex_color[2:4], 16) / 255,
+            "blue": int(hex_color[4:6], 16) / 255,
+        }
+
+        return rgb_color
+    except ValueError:
+        raise ValueError(f"Invalid character in hex color string: #{hex_color}")
+
+
+def convert_colors_to_hex_value(
+    red: float = 0.0, green: float = 0.0, blue: float = 0.0
+) -> str:
+    """Convert RGB color values to a hex color code.
+
+    :param float red: Red color value (0-1).
+    :param float green: Green color value (0-1).
+    :param float blue: Blue color value (0-1).
+
+    :returns: Hex color code in the format "#RRGGBB".
+    :rtype: str
+
+    :raises:
+        ValueError: If any color value is out of the accepted range (0-1).
+
+    Example:
+
+        >>> convert_colors_to_hex_value(0.2, 0, 0.8)
+        '#3300CC'
+
+        >>> convert_colors_to_hex_value(green=0.5)
+        '#008000'
+    """
+
+    def to_hex(value: float) -> str:
+        """
+        Convert an integer to a 2-digit uppercase hex string.
+        """
+        hex_value = hex(round(value * 255))[2:]
+        return hex_value.upper().zfill(2)
+
+    if any(value < 0 or value > 1 for value in (red, green, blue)):
+        raise ValueError("Color value out of accepted range 0-1.")
+
+    return f"#{to_hex(red)}{to_hex(green)}{to_hex(blue)}"
+
+
 if __name__ == "__main__":
     import doctest
 

gspread/worksheet.py

@@ -44,6 +44,7 @@
     cast_to_a1_notation,
     cell_list_to_rect,
     combined_merge_values,
+    convert_hex_to_colors_dict,
     fill_gaps,
     finditem,
     numericise_all,
@@ -1516,26 +1517,20 @@ def update_title(self, title: str) -> JSONResponse:
         self._properties["title"] = title
         return response
 
-    def update_tab_color(self, color: Mapping[str, float]) -> JSONResponse:
+    def update_tab_color(self, color: str) -> JSONResponse:
         """Changes the worksheet's tab color.
         Use clear_tab_color() to remove the color.
 
-        :param dict color: The red, green and blue values of the color, between 0 and 1.
+        :param str color:  Hex color value.
         """
-        red, green, blue = color["red"], color["green"], color["blue"]
+        rgb_color = convert_hex_to_colors_dict(color)
         body = {
             "requests": [
                 {
                     "updateSheetProperties": {
                         "properties": {
                             "sheetId": self.id,
-                            "tabColorStyle": {
-                                "rgbColor": {
-                                    "red": red,
-                                    "green": green,
-                                    "blue": blue,
-                                }
-                            },
+                            "tabColorStyle": {"rgbColor": rgb_color},
                         },
                         "fields": "tabColorStyle",
                     }
@@ -1545,13 +1540,7 @@ def update_tab_color(self, color: Mapping[str, float]) -> JSONResponse:
 
         response = self.client.batch_update(self.spreadsheet_id, body)
 
-        sheet_color = {
-            "red": red,
-            "green": green,
-            "blue": blue,
-        }
-
-        self._properties["tabColorStyle"] = {"rgbColor": sheet_color}
+        self._properties["tabColorStyle"] = {"rgbColor": rgb_color}
         return response
 
     def clear_tab_color(self) -> JSONResponse: