Cancellable tasks

kapitanbooru_uploader/ProgressFile.py

@@ -1,16 +1,21 @@
 # Klasa pomocnicza do monitorowania postępu uploadu
 class ProgressFile:
-    def __init__(self, f, callback, total_size):
+    def __init__(self, f, callback, total_size, cancel_event=None):
         self.f = f
         self.callback = callback
+        self.cancel_event = cancel_event
         self.total_size = total_size
         self.read_bytes = 0
 
     def read(self, size=-1):
+        # Check for cancellation before reading more data
+        if self.cancel_event is not None and self.cancel_event.is_set():
+            raise Exception("Upload cancelled by user.")
+
         data = self.f.read(size)
         self.read_bytes += len(data)
         self.callback(self.read_bytes, self.total_size)
         return data
 
     def __getattr__(self, attr):
-        return getattr(self.f, attr)
+        return getattr(self.f, attr)