updating backend Image component

- using matplotlib typing instead of Figure class
- added some checks and logs

src/pydase/components/image.py

@@ -1,19 +1,16 @@
 import base64
 import io
 from pathlib import Path
+from typing import TYPE_CHECKING, Optional
+from urllib.request import urlopen
 
 import PIL.Image
 from loguru import logger
-from urllib.request import urlopen
 
 from pydase.data_service.data_service import DataService
 
-
-class Figure:
-    """Mock class for matplotlib.Figure"""
-
-    def savefig(self, format="png"):
-        pass
+if TYPE_CHECKING:
+    from matplotlib.figure import Figure
 
 
 class Image(DataService):
@@ -36,19 +33,24 @@ class Image(DataService):
         with PIL.Image.open(path) as image:
             self._load_from_PIL(image)
 
-    def load_from_matplotlib_figure(self, fig: Figure, format_: str = "png") -> None:
+    def load_from_matplotlib_figure(self, fig: "Figure", format_: str = "png") -> None:
         buffer = io.BytesIO()
-        fig.savefig(buffer, format=format_)
+        fig.savefig(buffer, format=format_)  # type: ignore
         value_ = base64.b64encode(buffer.getvalue())
         self._load_from_base64(value_, format_)
 
-    def load_from_url(self, url: str):
+    def load_from_url(self, url: str) -> None:
         image = PIL.Image.open(urlopen(url))
         self._load_from_PIL(image)
 
-    def load_from_base64(self, value_: bytes, format_: str | None = None) -> None:
+    def load_from_base64(self, value_: bytes, format_: Optional[str] = None) -> None:
         if format_ is None:
             format_ = self._get_image_format_from_bytes(value_)
+            if format_ is None:
+                logger.warning(
+                    "Format of passed byte string could not be determined. Skipping..."
+                )
+                return
         self._load_from_base64(value_, format_)
 
     def _load_from_base64(self, value_: bytes, format_: str) -> None:
@@ -66,10 +68,9 @@ class Image(DataService):
         else:
             logger.error("Image format is 'None'. Skipping...")
 
-    def _get_image_format_from_bytes(self, value_: bytes):
+    def _get_image_format_from_bytes(self, value_: bytes) -> str | None:
         image_data = base64.b64decode(value_)
         # Create a writable memory buffer for the image
         image_buffer = io.BytesIO(image_data)
-        # Read the image from the buffer
-        image = PIL.Image.open(image_buffer)
-        return image.format
+        # Read the image from the buffer and return format
+        return PIL.Image.open(image_buffer).format