diff --git a/htagweb/fifo.py b/htagweb/fifo.py
index 4757b4e..fcf2d5f 100644
--- a/htagweb/fifo.py
+++ b/htagweb/fifo.py
@@ -79,7 +79,10 @@ async def com(self,command:str,**args) -> "str|dict":  # for client only
             frame = await fifo_in.readline()
 
             #print("Client receive:",frame)
-            c = json.loads(frame.strip())
+            try:
+                c = json.loads(frame.strip())
+            except json.decoder.JSONDecodeError as e:
+                raise Exception(f"fifo jcom json error '{e}' : '{frame}'")
             if "err" in c:
                 raise Exception(f"com error : {c['err']}")
             return c["response"]
diff --git a/htagweb/runners.py b/htagweb/runners.py
index ace1a93..85cf163 100644
--- a/htagweb/runners.py
+++ b/htagweb/runners.py
@@ -11,6 +11,7 @@
 
 #from shared_memory_dict import SharedMemoryDict
 
+import contextlib
 import asyncio
 import os,sys
 import sys
@@ -179,6 +180,7 @@ async def on_disconnect(self, websocket, close_code):
         # NO WAIT the cancellation of the task !!!!!!
 
 
+@contextlib.asynccontextmanager
 async def lifespan(app):
     print("--- START")
     await HrClient.clean()
@@ -186,6 +188,7 @@ async def lifespan(app):
     print("--- STOP")
     await HrClient.clean()
 
+
 class Runner(Starlette):
     def __init__(self,
                 obj:"Tag|fqn|None"=None,