Gracefully handle ConnectionErrors in proxy

Author: elprans

asyncpg/_testbase/fuzzer.py

@@ -247,37 +247,49 @@ async def _write(self, sock, data):
     async def proxy_to_backend(self):
         buf = None
 
-        while True:
-            await self.connectivity.wait()
-            if buf is not None:
-                data = buf
-                buf = None
-            else:
-                data = await self._read(self.client_sock, 4096)
-            if data == b'':
-                self.loop.call_soon(self.close)
-                break
-            if self.connectivity_loss.is_set():
-                if data:
-                    buf = data
-                continue
-            await self._write(self.backend_sock, data)
+        try:
+            while True:
+                await self.connectivity.wait()
+                if buf is not None:
+                    data = buf
+                    buf = None
+                else:
+                    data = await self._read(self.client_sock, 4096)
+                if data == b'':
+                    break
+                if self.connectivity_loss.is_set():
+                    if data:
+                        buf = data
+                    continue
+                await self._write(self.backend_sock, data)
+
+        except ConnectionError:
+            pass
+
+        finally:
+            self.loop.call_soon(self.close)
 
     async def proxy_from_backend(self):
         buf = None
 
-        while True:
-            await self.connectivity.wait()
-            if buf is not None:
-                data = buf
-                buf = None
-            else:
-                data = await self._read(self.backend_sock, 4096)
-            if data == b'':
-                self.loop.call_soon(self.close)
-                break
-            if self.connectivity_loss.is_set():
-                if data:
-                    buf = data
-                continue
-            await self._write(self.client_sock, data)
+        try:
+            while True:
+                await self.connectivity.wait()
+                if buf is not None:
+                    data = buf
+                    buf = None
+                else:
+                    data = await self._read(self.backend_sock, 4096)
+                if data == b'':
+                    break
+                if self.connectivity_loss.is_set():
+                    if data:
+                        buf = data
+                    continue
+                await self._write(self.client_sock, data)
+
+        except ConnectionError:
+            pass
+
+        finally:
+            self.loop.call_soon(self.close)