Attempting to open up an interactive viewer --> ImportError: cannot import name 'metadata' from 'importlib'

[eldad-a]

• npe2 version: 0.3.0
• Python version: 3.7.12
• Operating System: Linux 5.19.0-76051900-generic

Description

Attempting to open up a napari interactive viewer window fails with ImportError exception, both from command-line and jupyterlab.

Downgrading npe2 from 0.3.0 to 0.2.2 or 0.1.1 resolves for me; for example using conda:

conda install npe2=0.1.1

haven't tested other newer versions.

Issue may be related to importlib.metadata issue on import (Python 3.7 & Linux) #4747

What I Did

CLI:

napari

Exception

Traceback (most recent call last):                                                                        
  File "/home/UserName/lib/python/miniconda3/envs/hvDataLab/bin/napari", line 6, in <module>                                                                                                                          
    from napari.__main__ import main                                                                      
  File "/home/UserName/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/__main__.py", line 15, in <module>
    import napari.plugins._npe2 as _npe2                                                                  
  File "/home/UserName/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/plugins/__init__.py", line 3, in <module>                                                                              
    from npe2 import PluginManager as _PluginManager                                                      
  File "/home/UserName/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/npe2/__init__.py", line 8, in <module>
    from ._dynamic_plugin import DynamicPlugin                                                            
  File "/home/UserName/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/npe2/_dynamic_plugin.py", line 19, in <module>
    from ._plugin_manager import PluginManager                                                            
  File "/home/UserName/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/npe2/_plugin_manager.py", line 7, in <module>
    from importlib import metadata                                                                        
ImportError: cannot import name 'metadata' from 'importlib' (/home/UserName/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/__init__.py)

JLab

import os
os.environ['DISPLAY'] = ':1.0' ## get from `env |grep DISPLAY`
%gui qt5

from skimage import data
import napari

viewer = napari.view_image(data.astronaut(), rgb=True)

Exception

---------------------------------------------------------------------------
ImportError                               Traceback (most recent call last)
/tmp/ipykernel_722701/837316459.py in <module>
      2 import napari
      3 
----> 4 viewer = napari.view_image(data.astronaut(), rgb=True)

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/_lazy.py in __getattr__(name)
     45             return import_module(f'{module_name}.{name}')
     46         elif name in attr_to_modules:
---> 47             submod = import_module(f'{module_name}.{attr_to_modules[name]}')
     48             return getattr(submod, name)
     49         else:

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/__init__.py in import_module(name, package)
    125                 break
    126             level += 1
--> 127     return _bootstrap._gcd_import(name[level:], package, level)
    128 
    129 

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/_bootstrap.py in _gcd_import(name, package, level)

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/_bootstrap.py in _find_and_load(name, import_)

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/_bootstrap.py in _find_and_load_unlocked(name, import_)

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/_bootstrap.py in _load_unlocked(spec)

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/_bootstrap_external.py in exec_module(self, module)

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/_bootstrap.py in _call_with_frames_removed(f, *args, **kwds)

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/view_layers.py in <module>
     19 from napari.components.dims import Dims
     20 
---> 21 from .viewer import Viewer
     22 
     23 __all__ = [

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/viewer.py in <module>
      5 import magicgui as mgui
      6 
----> 7 from .components.viewer_model import ViewerModel
      8 from .utils import _magicgui, config
      9 

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/components/__init__.py in <module>
     17 from .camera import Camera
     18 from .dims import Dims
---> 19 from .layerlist import LayerList
     20 
     21 # Note that importing _viewer_key_bindings is needed as the Viewer gets

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/components/layerlist.py in <module>
      6 import numpy as np
      7 
----> 8 from ..layers import Layer
      9 from ..layers.image.image import _ImageBase
     10 from ..utils.context import create_context

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/layers/__init__.py in <module>
     10 from ..utils.misc import all_subclasses as _all_subcls
     11 from .base import Layer
---> 12 from .image import Image
     13 from .labels import Labels
     14 from .points import Points

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/layers/image/__init__.py in <module>
----> 1 from . import _image_key_bindings
      2 from .image import Image
      3 
      4 # Note that importing _image_key_bindings is needed as the Image layer gets
      5 # decorated with keybindings during that process, but it is not directly needed

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/layers/image/_image_key_bindings.py in <module>
      4 from ...utils.translations import trans
      5 from ._image_constants import Mode
----> 6 from .image import Image
      7 
      8 

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/layers/image/image.py in <module>
     10 from scipy import ndimage as ndi
     11 
---> 12 from ...utils import config
     13 from ...utils._dtype import get_dtype_limits, normalize_dtype
     14 from ...utils.colormaps import AVAILABLE_COLORMAPS

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/utils/config.py in <module>
      3 import os
      4 
----> 5 from ._octree import get_octree_config
      6 
      7 

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/utils/_octree.py in <module>
      9 from typing import Optional
     10 
---> 11 from ..settings import get_settings
     12 from ..utils.translations import trans
     13 

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/settings/__init__.py in <module>
      4 from ..utils.translations import trans
      5 from ._base import _NOT_SET
----> 6 from ._napari_settings import NapariSettings
      7 
      8 __all__ = ['NapariSettings', 'get_settings']

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/settings/_napari_settings.py in <module>
      7 from ..utils._base import _DEFAULT_CONFIG_PATH
      8 from ..utils.translations import trans
----> 9 from ._appearance import AppearanceSettings
     10 from ._application import ApplicationSettings
     11 from ._base import EventedConfigFileSettings

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/settings/_appearance.py in <module>
      2 
      3 from ..utils.events.evented_model import EventedModel
----> 4 from ..utils.theme import available_themes
      5 from ..utils.translations import trans
      6 from ._fields import Theme

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/utils/theme.py in <module>
    333 
    334 
--> 335 _install_npe2_themes(_themes)
    336 _themes.events.added.connect(rebuild_theme_settings)
    337 _themes.events.removed.connect(rebuild_theme_settings)

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/napari/utils/theme.py in _install_npe2_themes(_themes)
    323 # this function here instead of plugins._npe2 to avoid circular import
    324 def _install_npe2_themes(_themes):
--> 325     import npe2
    326 
    327     for theme in npe2.PluginManager.instance().iter_themes():

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/npe2/__init__.py in <module>
      6 __email__ = "[email protected]"
      7 
----> 8 from ._dynamic_plugin import DynamicPlugin
      9 from ._plugin_manager import PluginContext, PluginManager
     10 from .io_utils import read, read_get_reader, write, write_get_writer

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/npe2/_dynamic_plugin.py in <module>
     17 from typing_extensions import Literal
     18 
---> 19 from ._plugin_manager import PluginManager
     20 from .manifest.contributions import (
     21     CommandContribution,

~/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/site-packages/npe2/_plugin_manager.py in <module>
      5 from collections import Counter
      6 from fnmatch import fnmatch
----> 7 from importlib import metadata
      8 from pathlib import Path
      9 from typing import (

ImportError: cannot import name 'metadata' from 'importlib' (/home/eldada/lib/python/miniconda3/envs/hvDataLab/lib/python3.7/importlib/__init__.py)

---

Additional versions info that may be of relevance

Python implementation: CPython
Python version       : 3.7.12
IPython version      : 7.33.0

jupyterlab        : 3.4.6

napari: 0.4.14

Linux 5.19.0-76051900-generic #202207312230~1660780566~22.04~9d60db1 SMP PREEMPT_DYNAMIC Thu A x86_64 x86_64 x86_64 GNU/Linux

[tlambert03]

I'm afraid python 3.7 is no longer supported

[Czaki]

For people who will looking for a solution, you will need to use importlib-metadata<4.12.0