jupyter lab build fails on Windows

[PaulKGrimes]

After installing the extension in Jupyter Lab, and installing the package in the virtual environment via pip install jupyter-fs, Jupyter Lab says that it needs a rebuild.

This rebuild fails with an number of errors: ` [LabBuildApp] > node D:\Software\Anaconda3\envs\data-analysis\lib\site-packages\jupyterlab\staging\yarn.js run build:prod:minimize [LabBuildApp] yarn run v1.21.1 $ webpack --config webpack.prod.minimize.config.js [webpack-cli] [31mModuleNotFoundError: Module not found: Error: Can't resolve 'jupyter-fs/style/index.js' in 'D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\build' at D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\webpack\lib\Compilation.js:1768:28 at D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\webpack\lib\NormalModuleFactory.js:742:13 at eval (eval at create (D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\tapable\lib\HookCodeFactory.js:33:10), :10:1) at D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\webpack\lib\NormalModuleFactory.js:276:22 at eval (eval at create (D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\tapable\lib\HookCodeFactory.js:33:10), :9:1) at D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\webpack\lib\NormalModuleFactory.js:405:22 at D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\webpack\lib\NormalModuleFactory.js:119:11 at D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\webpack\lib\NormalModuleFactory.js:650:24 at D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\webpack\lib\NormalModuleFactory.js:813:8 at D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\webpack\lib\NormalModuleFactory.js:933:5 resolve 'jupyter-fs/style/index.js' in 'D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\build' Parsed request is a module using description file: D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\build\package.json (relative path: .) Field 'browser' doesn't contain a valid alias configuration resolve as module D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\build\node_modules doesn't exist or is not a directory looking for modules in D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules existing directory D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\jupyter-fs using description file: D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\jupyter-fs\package.json (relative path: .) using description file: D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\jupyter-fs\package.json (relative path: ./style/index.js) no extension Field 'browser' doesn't contain a valid alias configuration D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\jupyter-fs\style\index.js doesn't exist .js Field 'browser' doesn't contain a valid alias configuration D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\jupyter-fs\style\index.js.js doesn't exist .json Field 'browser' doesn't contain a valid alias configuration D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\jupyter-fs\style\index.js.json doesn't exist .wasm Field 'browser' doesn't contain a valid alias configuration D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\jupyter-fs\style\index.js.wasm doesn't exist as directory D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\staging\node_modules\jupyter-fs\style\index.js doesn't exist D:\Software\Anaconda3\envs\data-analysis\share\jupyter\lab\node_modules doesn't exist or is not a directory D:\Software\Anaconda3\envs\data-analysis\share\jupyter\node_modules doesn't exist or is not a directory D:\Software\Anaconda3\envs\data-analysis\share\node_modules doesn't exist or is not a directory looking for modules in D:\Software\Anaconda3\envs\data-analysis\node_modules D:\Software\Anaconda3\envs\data-analysis\node_modules\jupyter-fs doesn't exist D:\Software\Anaconda3\envs\node_modules doesn't exist or is not a directory looking for modules in D:\Software\Anaconda3\node_modules D:\Software\Anaconda3\node_modules\jupyter-fs doesn't exist D:\Software\node_modules doesn't exist or is not a directory D:\node_modules doesn't exist or is not a directory[39m error Command failed with exit code 2. info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

[LabBuildApp] JupyterLab failed to build [LabBuildApp] Traceback (most recent call last):

[LabBuildApp] File "D:\Software\Anaconda3\envs\data-analysis\lib\site-packages\jupyterlab\debuglog.py", line 47, in debug_logging yield

[LabBuildApp] File "D:\Software\Anaconda3\envs\data-analysis\lib\site-packages\jupyterlab\labapp.py", line 196, in start raise e

[LabBuildApp] File "D:\Software\Anaconda3\envs\data-analysis\lib\site-packages\jupyterlab\labapp.py", line 187, in start build(

[LabBuildApp] File "D:\Software\Anaconda3\envs\data-analysis\lib\site-packages\jupyterlab\commands.py", line 506, in build return handler.build(

[LabBuildApp] File "D:\Software\Anaconda3\envs\data-analysis\lib\site-packages\jupyterlab\commands.py", line 722, in build raise RuntimeError(msg)

[LabBuildApp] RuntimeError: JupyterLab failed to build

[LabBuildApp] Exiting application: JupyterLab `

The error associated with the Field 'browser' doesn't contain a valid alias configuration line may be due to ../ci/browser.sh not being included in the pip distributed package, but this may be a spurious issue.

[PaulKGrimes]

This appears to be because ./style/index.js is missing in the downloaded package I received.

Manually creating this file got the build to work.