Merge pull request #154 from aria1th/fix-pnginfo-compat

fix PNGInfo Related usage (fix NoneType does not have encode method)

agent_scheduler/task_helpers.py

@@ -65,10 +65,14 @@ def encode_image_to_base64(image):
 
     geninfo, _ = images.read_info_from_image(image)
     pnginfo = PngImagePlugin.PngInfo()
-    pnginfo.add_text("parameters", geninfo)
+    if geninfo:
+        pnginfo.add_text("parameters", geninfo)
 
     with io.BytesIO() as output_bytes:
-        image.save(output_bytes, format="PNG", pnginfo=pnginfo)
+        if geninfo:
+            image.save(output_bytes, format="PNG", pnginfo=pnginfo)
+        else:
+            image.save(output_bytes, format="PNG") # remove pnginfo to save space
         bytes_data = output_bytes.getvalue()
         return "data:image/png;base64," + base64.b64encode(bytes_data).decode("utf-8")