_load_jupyter_server_extension function was not found

[jbwhit]

I'm not sure what functionality is missing, but I've installed/reinstalled jupysql and jupysql_plugin and still get the following error messages from the output of my terminal running jupyter lab.

jupysql_plugin | extension failed loading with message: ExtensionLoadingError('_load_jupyter_server_extension function was not found.')
    Traceback (most recent call last):
      File "/Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 360, in load_extension
        extension.load_all_points(self.serverapp)
      File "/Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 232, in load_all_points
        return [self.load_point(point_name, serverapp) for point_name in self.extension_points]
      File "/Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 232, in <listcomp>
        return [self.load_point(point_name, serverapp) for point_name in self.extension_points]
      File "/Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 223, in load_point
        return point.load(serverapp)
      File "/Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 150, in load
        loader = self._get_loader()
      File "/Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 119, in _get_loader
        loader = get_loader(loc)
      File "/Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages/jupyter_server/extension/utils.py", line 40, in get_loader
        raise ExtensionLoadingError(msg) from None
    jupyter_server.extension.utils.ExtensionLoadingError: _load_jupyter_server_extension function was not found.

Here's what I see when I run update:

❯ pip install --upgrade jupysql_plugin
Requirement already satisfied: jupysql_plugin in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (0.4.3)
Requirement already satisfied: ploomber-core in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from jupysql_plugin) (0.2.25)
Requirement already satisfied: pyyaml in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from ploomber-core->jupysql_plugin) (6.0.1)
Requirement already satisfied: posthog in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from ploomber-core->jupysql_plugin) (3.5.0)
Requirement already satisfied: requests<3.0,>=2.7 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from posthog->ploomber-core->jupysql_plugin) (2.31.0)
Requirement already satisfied: six>=1.5 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from posthog->ploomber-core->jupysql_plugin) (1.16.0)
Requirement already satisfied: monotonic>=1.5 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from posthog->ploomber-core->jupysql_plugin) (1.5)
Requirement already satisfied: backoff>=1.10.0 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from posthog->ploomber-core->jupysql_plugin) (2.2.1)
Requirement already satisfied: python-dateutil>2.1 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from posthog->ploomber-core->jupysql_plugin) (2.9.0)
Requirement already satisfied: charset-normalizer<4,>=2 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from requests<3.0,>=2.7->posthog->ploomber-core->jupysql_plugin) (3.3.2)
Requirement already satisfied: idna<4,>=2.5 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from requests<3.0,>=2.7->posthog->ploomber-core->jupysql_plugin) (3.7)
Requirement already satisfied: urllib3<3,>=1.21.1 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from requests<3.0,>=2.7->posthog->ploomber-core->jupysql_plugin) (2.2.1)
Requirement already satisfied: certifi>=2017.4.17 in /Users/jonathan/mambaforge/envs/mastery/lib/python3.10/site-packages (from requests<3.0,>=2.7->posthog->ploomber-core->jupysql_plugin) (2024.2.2)

Let me know if I can provide more information to help.

Mac OS Sonoma 14.4.1

[edublancas]

@neelasha23 can you take a look? I remember a similar issue on jupysql's repository but can't remember what the conclusion was

[neelasha23]

The jupyter server config files already exist in jupysql-plugin. So might be some path or package version issues. Here's the steps I tried on Mac Sonoma 14.1:

1. Create a virtual environment
2. pip install jupysql jupyterlab.
3. Ensure jupyterlab is started from the virtual environment :

import sys
print(sys.executable)

If that's not the case please modify the PATH variable so it starts properly.

Here is the dependency lock file for your reference:

requirements.lock.txt

I think this issue is related. You can try downgrading the JupyterLab version also.

Please let me know if this doesn't help. More info on your package versions would be helpful

@jbwhit

[edublancas]

I suspect this is because you're running jupysql-plugin 0.4.x in Jupyterlab 3.x

I checked the source code for jupysql-plugin 0.3.1 and there is a _load_jupyter_server_extension function

either upgrade jupyterlab or downgrade jupysql-plugin (example: pip install "jupysql-plugin<0.4.0")

closing, but feel free to re-open if this doesn't fix the issue

[jbwhit]

No, I'm not doing anything like that. I just created a new environment.

Here's what I just did:

mamba create --channel conda-forge --name jupybug python=3.10 jupyterlab jupyter notebook jupysql
mamba activate jupybug

❯ jupyter --version
Selected Jupyter core packages...
IPython          : 8.22.2
ipykernel        : 6.29.3
ipywidgets       : 8.1.2
jupyter_client   : 7.4.9
jupyter_core     : 5.7.2
jupyter_server   : 2.14.0
jupyterlab       : 4.2.0
nbclient         : 0.10.0
nbconvert        : 7.16.4
nbformat         : 5.10.4
notebook         : 6.5.6
qtconsole        : 5.5.2
traitlets        : 5.14.3


jupyter lab

Going into the extensions tab in the browser, I see the following:

I uninstall jupysql_plugin, reinstall, close down jupyter lab. Restart it and see the following:

❯ jupyter lab
[I 2024-05-08 21:07:03.108 ServerApp] jupysql_plugin | extension was successfully linked.
[I 2024-05-08 21:07:03.109 ServerApp] jupyter_lsp | extension was successfully linked.
[I 2024-05-08 21:07:03.112 ServerApp] jupyter_server_terminals | extension was successfully linked.
[I 2024-05-08 21:07:03.117 ServerApp] jupyterlab | extension was successfully linked.
[I 2024-05-08 21:07:03.120 ServerApp] nbclassic | extension was successfully linked.
[I 2024-05-08 21:07:03.295 ServerApp] notebook_shim | extension was successfully linked.
/Users/jonathan/mambaforge/envs/jupybug/lib/python3.10/site-packages/traitlets/traitlets.py:1241: UserWarning: Overriding existing pre_save_hook (nbdev_clean_jupyter) with a new one (nbdev_clean_jupyter).
  return self.func(*args, **kwargs)
[I 2024-05-08 21:07:03.358 ServerApp] notebook_shim | extension was successfully loaded.
[W 2024-05-08 21:07:03.358 ServerApp] jupysql_plugin | extension failed loading with message: ExtensionLoadingError('_load_jupyter_server_extension function was not found.')
    Traceback (most recent call last):
      File "/Users/jonathan/mambaforge/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 360, in load_extension
        extension.load_all_points(self.serverapp)
      File "/Users/jonathan/mambaforge/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 232, in load_all_points
        return [self.load_point(point_name, serverapp) for point_name in self.extension_points]
      File "/Users/jonathan/mambaforge/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 232, in <listcomp>
        return [self.load_point(point_name, serverapp) for point_name in self.extension_points]
      File "/Users/jonathan/mambaforge/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 223, in load_point
        return point.load(serverapp)
      File "/Users/jonathan/mambaforge/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 150, in load
        loader = self._get_loader()
      File "/Users/jonathan/mambaforge/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 119, in _get_loader
        loader = get_loader(loc)
      File "/Users/jonathan/mambaforge/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/utils.py", line 40, in get_loader
        raise ExtensionLoadingError(msg) from None
    jupyter_server.extension.utils.ExtensionLoadingError: _load_jupyter_server_extension function was not found.

Perhaps it's a mamba thing? A conda-forge thing?

If I have time later I'll do the pip thing in another environment and report if it's having the same issues.

[edublancas]

I reproduced the error:

conda create --channel conda-forge --name jupybug python=3.10 jupyterlab jupyter notebook jupysql
conda activate jupybug

Yields:

[W 2024-05-09 08:24:17.892 ServerApp] jupysql_plugin | extension failed loading with message: ExtensionLoadingError('_load_jupyter_server_extension function was not found.')
    Traceback (most recent call last):
      File "/Users/eduardo/miniconda3/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 360, in load_extension
        extension.load_all_points(self.serverapp)
      File "/Users/eduardo/miniconda3/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 232, in load_all_points
        return [self.load_point(point_name, serverapp) for point_name in self.extension_points]
      File "/Users/eduardo/miniconda3/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 232, in <listcomp>
        return [self.load_point(point_name, serverapp) for point_name in self.extension_points]
      File "/Users/eduardo/miniconda3/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 223, in load_point
        return point.load(serverapp)
      File "/Users/eduardo/miniconda3/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 150, in load
        loader = self._get_loader()
      File "/Users/eduardo/miniconda3/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/manager.py", line 119, in _get_loader
        loader = get_loader(loc)
      File "/Users/eduardo/miniconda3/envs/jupybug/lib/python3.10/site-packages/jupyter_server/extension/utils.py", line 40, in get_loader
        raise ExtensionLoadingError(msg) from None
    jupyter_server.extension.utils.ExtensionLoadingError: _load_jupyter_server_extension function was not found.

I think this is actually a warning: shows in yellow and the extension works (ran the Format SQL button).

I now remember we had a user report this problem and the conclusion was the same (it's a warning). possibly due to a breaking change in JupyterLab. Does the extension work for you or is it broken?

[jbwhit]

The format SQL button works. Is there any other functionality that I should test?

[edublancas]

No, the plugin has two features: format SQL and notebook sharing, but we're deprecating the latter so there's no point in testing that.

[edublancas]

closing due to inactivity