strange ui.code behavior - strange startup behavior

[WolfgangFahl]

Question

I am trying

def setup_ui(self):
        """Create the NiceGUI user interface"""
        try:
            ui.label("M-Bus Message Parser").classes("text-h4 q-mb-md")

            self.example_select = ui.select(
                label="Select Example",
                options=list(self.examples.keys()),
                on_change=self.on_example_change,
            ).classes("w-full q-mb-md")

            self.example_details = ui.html().classes("w-full mb-4")

            self.hex_input = self.createTextArea(
                label="Enter M-Bus hex message",
                placeholder="e.g. 68 4d 4d 68 08 00 72 26 54 83 22 77...",
                classes="h-32",
            )

            with ui.row() as self.button_row:
                ui.button("Parse Message", on_click=self.on_parse).classes("q-mt-md")
            with ui.row() as self.result_row:
                self.error_view = ui.html()
                self.json_code = ui.code(content="",language="json").classes("w-full h-96 q-mt-md")
        except Exception as ex:
            self.solution.handle_exception(ex)

and get

 mbus-viewer --host 0.0.0.0 --port 9999 -s
NiceGUI ready to go on http://localhost:9999, http://172.17.0.1:9999, http://172.18.0.1:9999, http://192.168.32.1:9999, and http://92.205.190.211:9999
min() arg is an empty sequence
Traceback (most recent call last):
  File "/home/wf/.local/lib/python3.10/site-packages/ngwidgets/webserver.py", line 493, in setup_content_div
    setup_content(**kwargs)
  File "/home/wf/.local/lib/python3.10/site-packages/mbusread/mbus_viewer_server.py", line 68, in setup_home
    viewer.setup_ui()
  File "/home/wf/.local/lib/python3.10/site-packages/mbusread/mbus_viewer.py", line 83, in setup_ui
    self.json_code = ui.code(language="json").classes("w-full h-96 q-mt-md")
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/elements/code.py", line 29, in __init__
    .bind_content_from(self, 'content', lambda content: f'```{language}\n{content}\n```')
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/elements/mixins/content_element.py", line 50, in bind_content_from
    bind_from(self, 'content', target_object, target_name, backward)
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/binding.py", line 113, in bind_from
    _propagate(other_obj, other_name)
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/binding.py", line 76, in _propagate
    _set_attribute(target_obj, target_name, target_value)
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/binding.py", line 33, in _set_attribute
    setattr(obj, name, value)
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/binding.py", line 155, in __set__
    self._change_handler(owner, value)
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/elements/mixins/content_element.py", line 12, in <lambda>
    on_change=lambda sender, content: cast(Self, sender)._handle_content_change(content))  # pylint: disable=protected-access
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/elements/markdown.py", line 45, in _handle_content_change
    html = prepare_content(content, extras=' '.join(self.extras))
  File "/home/wf/.local/lib/python3.10/site-packages/nicegui/elements/markdown.py", line 54, in prepare_content
    return markdown2.markdown(remove_indentation(content), extras=extras.split())
  File "/home/wf/.local/lib/python3.10/site-packages/markdown2.py", line 170, in markdown
    use_file_vars=use_file_vars, cli=cli).convert(text)
  File "/home/wf/.local/lib/python3.10/site-packages/markdown2.py", line 355, in convert
    text = self._do_fenced_code_blocks(text)
  File "/home/wf/.local/lib/python3.10/site-packages/markdown2.py", line 2092, in _do_fenced_code_blocks
    return self._fenced_code_block_re.sub(self._fenced_code_block_sub, text)
  File "/home/wf/.local/lib/python3.10/site-packages/markdown2.py", line 2088, in _fenced_code_block_sub
    return self._code_block_sub(match, is_fenced_code_block=True)
  File "/home/wf/.local/lib/python3.10/site-packages/markdown2.py", line 1989, in _code_block_sub
    return self._code_block_with_lexer_sub(codeblock, leading_indent, lexer, is_fenced_code_block)
  File "/home/wf/.local/lib/python3.10/site-packages/markdown2.py", line 2037, in _code_block_with_lexer_sub
    _, codeblock = self._uniform_outdent(codeblock, max_outdent=leading_indent)
  File "/home/wf/.local/lib/python3.10/site-packages/markdown2.py", line 2614, in _uniform_outdent
    outdent = min(i for i in whitespace if i is not None)
ValueError: min() arg is an empty sequence

with the latest nicegui / venv it even get's worse:

cat /var/log/mbus/mbus.log 
NiceGUI ready to go on http://localhost:9852
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/nicegui.css not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/vue.global.prod.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/quasar.prod.css not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/es-module-shims.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/quasar.umd.prod.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/fonts.css not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/tailwindcss.min.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/socket.io.min.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/nicegui.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/lang/en-US.umd.prod.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/vue.global.prod.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/quasar.umd.prod.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/nicegui.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/lang/en-US.umd.prod.js not found
WARNING:nicegui:http://localhost:9852/_nicegui/2.10.1/static/favicon.ico not found
ERROR:nicegui:No connection after 6.0 seconds
Traceback (most recent call last):
  File "/home/wf/source/python/mbus/.venv/lib/python3.10/site-packages/nicegui/background_tasks.py", line 52, in _handle_task_result
    task.result()
  File "/home/wf/source/python/mbus/.venv/lib/python3.10/site-packages/nicegui/page.py", line 125, in wait_for_result
    return await result
  File "/home/wf/source/python/mbus/.venv/lib/python3.10/site-packages/ngwidgets/input_webserver.py", line 30, in home_page
    return await self.page(client, InputWebSolution.home)
  File "/home/wf/source/python/mbus/.venv/lib/python3.10/site-packages/ngwidgets/webserver.py", line 161, in page
    await solution_instance.prepare()
  File "/home/wf/source/python/mbus/.venv/lib/python3.10/site-packages/ngwidgets/webserver.py", line 268, in prepare
    await self.client.connected(timeout=timeout)
  File "/home/wf/source/python/mbus/.venv/lib/python3.10/site-packages/nicegui/client.py", line 178, in connected
    raise TimeoutError(f'No connection after {timeout} seconds')
TimeoutError: No connection after 6.0 seconds
ERROR:asyncio:Exception in callback <function page.__call__.<locals>.check_for_late_return_value at 0x7fd56fac8af0>
handle: <Handle page.__call__.<locals>.check_for_late_return_value>
Traceback (most recent call last):
  File "uvloop/cbhandles.pyx", line 63, in uvloop.loop.Handle._run
  File "/home/wf/source/python/mbus/.venv/lib/python3.10/site-packages/nicegui/page.py", line 107, in check_for_late_return_value
    if task.result() is not None:
TimeoutError: No connection after 6.0 seconds

on my Mac things work but no on my Ubuntu machine where i host all my other apps.

[falkoschindler]

@WolfgangFahl Please, please, please provide a minimum reproducible example when asking for help!
Especially (but not only) if the stacktrace points to markdown.py, but there's not a single Markdown element in your code. Ok, I noticed ui.code uses ui.markdown under the hood. Anyway.

[WolfgangFahl]

the first error goes away when i upgrade markdown2. The second error goes away when i downgrade nicegui to 2.9.1.
Unfortunately i do not know how to reproduce the error with a minum example given that the error is arising from the complexity of the environment. That's why i did not make this an issue but a discussion element for a start - just in case other people pump into similar problems. First i was fearing the port could be a problem but i changed the default port and if i do not run in venv with all the latest deps i am also fine. So it seems there are some strang deps under the hood causing this. If you are lucky https://mbus.bitplan.com/
will be available. But if not https://github.com/WolfgangFahl/mbusreader has the state of affairs.

[WolfgangFahl]

see also https://stackoverflow.com/questions/79383390/creating-a-diff-of-to-python-venv-pip-freeze

venvdiff --diff source/python/mbus source/python/ngdemo/
Packages only in the first virtual environment:
Deprecated==1.2.15
MarkupSafe==3.0.2
PyGithub==2.5.0
PyJWT==2.10.1
PyYAML==6.0.2
Pygments==2.19.1
aiofiles==24.1.0
aiohappyeyeballs==2.4.4
aiohttp==3.11.11
aiosignal==1.3.2
annotated-types==0.7.0
anyio==4.8.0
async-timeout==5.0.1
attrs==24.3.0
bcrypt==4.2.1
beautifulsoup4==4.12.3
bidict==0.23.1
certifi==2024.12.14
cffi==1.17.1
charset-normalizer==3.4.1
click==8.1.8
cryptography==44.0.0
dataclasses-json==0.6.7
docutils==0.21.2
exceptiongroup==1.2.2
fastapi==0.115.7
frozenlist==1.5.0
httpcore==1.0.7
httptools==0.6.4
httpx==0.28.1
idna==3.10
itsdangerous==2.2.0
jiter==0.8.2
markdown2==2.5.2
marshmallow==3.26.0
mbusreader @ file:///home/wf/source/python/mbus
multidict==6.1.0
ngwidgets==0.21.0
nicegui==2.9.1
openai==1.60.0
orjson==3.10.15
packaging==24.2
propcache==0.2.1
pycparser==2.22
pydantic==2.10.5
pydantic_core==2.27.2
pydevd==3.2.3
python-dateutil==2.9.0.post0
python-dotenv==1.0.1
python-engineio==4.11.2
python-socketio==5.12.1
pytz==2024.2
simple-websocket==1.1.0
six==1.17.0
sniffio==1.3.1
soupsieve==2.6
starlette==0.45.2
tqdm==4.67.1
typing_extensions==4.12.2
urllib3==2.3.0
uvicorn==0.34.0
uvloop==0.21.0
watchfiles==1.0.4
websockets==14.2
wrapt==1.17.2
yarl==1.18.3

Packages only in the second virtual environment:
Deprecated==1.2.14
MarkupSafe==2.1.3
PyGithub==2.1.1
PyJWT==2.8.0
PyYAML==6.0.1
Pygments==2.16.1
aiofiles==23.2.1
aiohappyeyeballs==2.4.0
aiohttp==3.10.5
aiosignal==1.3.1
annotated-types==0.6.0
anyio==3.7.1
async-timeout==4.0.3
attrs==23.1.0
bcrypt==4.0.1
beautifulsoup4==4.12.2
bidict==0.22.1
certifi==2024.7.4
cffi==1.16.0
charset-normalizer==3.3.1
click==8.1.7
cryptography==41.0.7
dataclasses-json==0.6.3
docutils==0.19
exceptiongroup==1.1.3
fastapi-socketio==0.0.10
fastapi==0.109.2
frozenlist==1.4.0
httpcore==0.18.0
httptools==0.6.1
httpx==0.25.0
idna==3.4
itsdangerous==2.1.2
markdown2==2.4.10
marshmallow==3.20.2
multidict==6.0.4
ngwidgets @ file:///home/wf/source/python/ngdemo
nicegui==2.10.1
openai==1.12.0
orjson==3.9.15
packaging==23.2
pycparser==2.21
pydantic==2.4.2
pydantic_core==2.10.1
pydevd==2.10.0
python-dateutil==2.8.2
python-dotenv==1.0.0
python-engineio==4.8.0
python-socketio==5.10.0
pytz==2023.3.post1
simple-websocket==1.0.0
six==1.16.0
sniffio==1.3.0
soupsieve==2.5
starlette==0.36.3
tqdm==4.66.1
typing_extensions==4.8.0
urllib3==2.2.2
uvicorn==0.22.0
uvloop==0.19.0
watchfiles==0.21.0
websockets==12.0
wrapt==1.16.0
yarl==1.9.2

Common packages with version differences:
join: /tmp/tmp.Sx7U1q0awr:32: is not sorted: fastapi==0.109.2
join: input is not in sorted order
Deprecated==1.2.14 vs Deprecated==1.2.15
MarkupSafe==2.1.3 vs MarkupSafe==3.0.2
PyGithub==2.1.1 vs PyGithub==2.5.0
PyJWT==2.8.0 vs PyJWT==2.10.1
PyYAML==6.0.1 vs PyYAML==6.0.2
Pygments==2.16.1 vs Pygments==2.19.1
aiofiles==23.2.1 vs aiofiles==24.1.0
aiohappyeyeballs==2.4.0 vs aiohappyeyeballs==2.4.4
aiohttp==3.10.5 vs aiohttp==3.11.11
aiosignal==1.3.1 vs aiosignal==1.3.2
annotated-types==0.6.0 vs annotated-types==0.7.0
anyio==3.7.1 vs anyio==4.8.0
async-timeout==4.0.3 vs async-timeout==5.0.1
attrs==23.1.0 vs attrs==24.3.0
bcrypt==4.0.1 vs bcrypt==4.2.1
beautifulsoup4==4.12.2 vs beautifulsoup4==4.12.3
bidict==0.22.1 vs bidict==0.23.1
certifi==2024.7.4 vs certifi==2024.12.14
cffi==1.16.0 vs cffi==1.17.1
charset-normalizer==3.3.1 vs charset-normalizer==3.4.1
click==8.1.7 vs click==8.1.8
cryptography==41.0.7 vs cryptography==44.0.0
dataclasses-json==0.6.3 vs dataclasses-json==0.6.7
docutils==0.19 vs docutils==0.21.2
exceptiongroup==1.1.3 vs exceptiongroup==1.2.2
fastapi==0.109.2 vs fastapi==0.115.7
frozenlist==1.4.0 vs frozenlist==1.5.0
httpcore==0.18.0 vs httpcore==1.0.7
httptools==0.6.1 vs httptools==0.6.4
httpx==0.25.0 vs httpx==0.28.1
idna==3.4 vs idna==3.10
itsdangerous==2.1.2 vs itsdangerous==2.2.0
markdown2==2.4.10 vs markdown2==2.5.2
marshmallow==3.20.2 vs marshmallow==3.26.0
multidict==6.0.4 vs multidict==6.1.0
nicegui==2.10.1 vs nicegui==2.9.1
openai==1.12.0 vs openai==1.60.0
orjson==3.9.15 vs orjson==3.10.15
packaging==23.2 vs packaging==24.2
pycparser==2.21 vs pycparser==2.22
pydantic==2.4.2 vs pydantic==2.10.5
pydantic_core==2.10.1 vs pydantic_core==2.27.2
pydevd==2.10.0 vs pydevd==3.2.3
python-dateutil==2.8.2 vs python-dateutil==2.9.0.post0
python-dotenv==1.0.0 vs python-dotenv==1.0.1
python-engineio==4.8.0 vs python-engineio==4.11.2
python-socketio==5.10.0 vs python-socketio==5.12.1
pytz==2023.3.post1 vs pytz==2024.2
simple-websocket==1.0.0 vs simple-websocket==1.1.0
six==1.16.0 vs six==1.17.0
sniffio==1.3.0 vs sniffio==1.3.1
soupsieve==2.5 vs soupsieve==2.6
starlette==0.36.3 vs starlette==0.45.2
tqdm==4.66.1 vs tqdm==4.67.1
typing_extensions==4.8.0 vs typing_extensions==4.12.2
urllib3==2.2.2 vs urllib3==2.3.0
uvicorn==0.22.0 vs uvicorn==0.34.0
uvloop==0.19.0 vs uvloop==0.21.0
watchfiles==0.21.0 vs watchfiles==1.0.4
websockets==12.0 vs websockets==14.2
wrapt==1.16.0 vs wrapt==1.17.2
yarl==1.9.2 vs yarl==1.18.3