Make exceptions shorter to not (completely) bloat the UI.

chat.py

@@ -1,8 +1,7 @@
 import json
 import re
 import time
-import traceback
-
+from datetime import datetime
 import gradio as gr
 
 import chat_client
@@ -84,9 +83,9 @@ def _generate(
             state["client"] = chat_client.ModelClient(CHAT_URL)
             state["client"].open_session(f"bigscience/{model}-petals", max_length)
             state["model"] = model
-        except Exception:
-            print(traceback.format_exc())
-            raise gr.Error(traceback.format_exc(limit=3))
+        except Exception as e:
+            print(datetime.now(), str(e)[-500:])
+            raise gr.Error(str(e)[-500:])
 
     else:
         context = ""
@@ -185,13 +184,13 @@ def _generate(
 
         print("Broken session!")
         raise
-    except Exception:
+    except Exception as e:
         client.close_session()
         state["client"] = None
         state["model"] = None
 
-        print(traceback.format_exc())
-        raise gr.Error(traceback.format_exc(limit=3))
+        print(datetime.now(), str(e)[-500:])
+        raise gr.Error(str(e)[-500:])
 
 
 def reset(state):

prompt.py

@@ -1,6 +1,5 @@
 import time
-import traceback
-
+from datetime import datetime
 import gradio as gr
 
 import chat_client
@@ -50,9 +49,9 @@ def _generate(
     try:
         client = chat_client.ModelClient(CHAT_URL)
         client.open_session(f"bigscience/{model}-petals", max_length)
-    except Exception:
-        print(traceback.format_exc())
-        raise gr.Error(traceback.format_exc(limit=3))
+    except Exception as e:
+        print(datetime.now(), str(e)[-500:])
+        raise gr.Error(str(e)[-500:])
 
     if add_stoptoken:
         prompt += "</s>" if "bloomz" in model else "\n\n"
@@ -112,9 +111,9 @@ def _generate(
 
         # Prints final result w/o statistics
         yield state, prompt2, output
-    except Exception:
-        print(traceback.format_exc())
-        raise gr.Error(traceback.format_exc(limit=3))
+    except Exception as e:
+        print(datetime.now(), str(e)[-500:])
+        raise gr.Error(str(e)[-500:])
 
 
 def stop(state):