Recursion depth error in table.add_rows?

[ed2050]

Question

Anyone know what causes a recursion depth error in socketio with ui.table.add_rows? All I found on boards is #1212 which isn't related (don't use on_air).

What happens: page loads fine, I click a button to filter results, call table.add_rows (rowdata), and blamo recursion error. Traceback below, no app files only nicegui and socketio.rowdata is a list of dicts.

If I call table.add_rows (*rowdata) instead then no error. Everything works perfectly. However I'm concerned about passing so many args / copying so much data to the callstack. Some tables have 10s of thousands of rows. Passing a ref to rowdata would be better if not for the recursion error.

Error message

maximum recursion depth exceeded while calling a Python object
Traceback (most recent call last):
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/nicegui/outbox.py", line 62, in loop
    await coro
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/nicegui/outbox.py", line 34, in _emit
    await globals.sio.emit(message_type, data, room=target_id)
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/asyncio_server.py", line 168, in emit
    await self.manager.emit(event, data, namespace, room=room,
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/asyncio_manager.py", line 36, in emit
    pkt = self.server.packet_class(
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/packet.py", line 32, in __init__
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/packet.py", line 172, in _data_is_binary
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/packet.py", line 172, in <listcomp>
    lambda a, b: a or b, [self._data_is_binary(item)
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/packet.py", line 172, in _data_is_binary
    lambda a, b: a or b, [self._data_is_binary(item)
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/packet.py", line 172, in <listcomp>
    lambda a, b: a or b, [self._data_is_binary(item)

... same 2 lines repeat hundreds more times then...

  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/packet.py", line 172, in <listcomp>
    lambda a, b: a or b, [self._data_is_binary(item)
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/packet.py", line 172, in _data_is_binary
  File "/Users/ed2050/Library/Python/3.8/lib/python/site-packages/socketio/packet.py", line 168, in _data_is_binary
    if isinstance(data, bytes):
RecursionError: maximum recursion depth exceeded while calling a Python object

[falkoschindler]

Hi @ed2050,

Can you, please, share code to reproduce the recursion error?

[ed2050]

@falkoschindler haven't found the trigger yet. It consistently causes recursion error in my app. Same setup in test script behaves badly (table doesn't update) but no recursion error.

Here's test script. I added things that seem extraneous trying to trigger recursion error. Line marked "doesnt work" adds no rows to table. Same line in my app triggers recursion error.

import nicegui
from nicegui import ui

def update (table, data) :
    print (f'updating table : { len (data) }')
    table.rows [:] = []
    table.add_rows (data)    # doesnt work, no rows added
    #table.add_rows (*data)  # this version works fine
    table.update ()

# ---

cols = [] 
fields = [ 'title', 'author', 'year' , 'link' ]
for field in fields :
    cols.append ({'name' : field , 'label' : field , 'field' : field , 'align' : 'left'})

data1 = [ { x : 'foo' for x in fields } ] * 50000
data2 = [ { x : 'bar' for x in fields } ] * 50000

# ---

def mainpage () :
    
    ui.label ('Recursion test')
    button = ui.button ('update')
        
    table = ui.table (
        columns = cols ,
        rows = data1 ,
        pagination = { 'rowsPerPage' : 20 } ,
    )
    table.add_slot ('body-cell-link', r'<td class="test" :props="props"> <a :href="props.row.link"> {{props.row.link}} </a> </td>')
    
    button.on ('click', lambda : update (table, data2))

# ---

if __name__ in {"__main__", "__mp_main__"} :
    ui.run (dark = True)
    mainpage ()

[falkoschindler]

You're probably using NiceGUI 1.4.x, where table.add_rows(*data) was the right way to add rows. Since 2.0.0 you can pass a list of dictionaries like table.add_rows(data).

But this doesn't explain the recursion error. Without a way to reproduce or narrow down the problem, it's hard to do anything about it.

[ed2050]

You're probably using NiceGUI 1.4.x, where table.add_rows(*data) was the right way to add rows. Since 2.0.0 you can pass a list of dictionaries like table.add_rows(data).

Yes. I'd expect some kind of error rather than silent failure when passing table.add_rows (data) in 1.4, but c'est la vie. No sense updating it now.

But this doesn't explain the recursion error. Without a way to reproduce or narrow down the problem, it's hard to do anything about it.

Understood, thanks. Haven't been able to reproduce it yet. Other priorities now, will come back to it when I can.