Error when following contribution guide

[PyroGenesis]

Describe the bug
I am trying to build chainlit on my local Windows system. However, I'm running into an error on the step Start the Chainlit server from source

Traceback (most recent call last):
  File "C:\Projects\chainlit\backend\.venv\Scripts\chainlit", line 6, in <module>
    sys.exit(cli())
  File "C:\Projects\chainlit\backend\.venv\lib\site-packages\click\core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
  File "C:\Projects\chainlit\backend\.venv\lib\site-packages\click\core.py", line 1078, in main
    rv = self.invoke(ctx)
  File "C:\Projects\chainlit\backend\.venv\lib\site-packages\click\core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "C:\Projects\chainlit\backend\.venv\lib\site-packages\click\core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "C:\Projects\chainlit\backend\.venv\lib\site-packages\click\core.py", line 783, in invoke
    return __callback(*args, **kwargs)
  File "C:\Projects\chainlit\backend\chainlit\cli\__init__.py", line 201, in chainlit_run
    run_chainlit(target)
  File "C:\Projects\chainlit\backend\chainlit\cli\__init__.py", line 39, in run_chainlit
    from chainlit.server import app
  File "C:\Projects\chainlit\backend\chainlit\server.py", line 184, in <module>
    build_dir = get_build_dir("frontend", "frontend")
  File "C:\Projects\chainlit\backend\chainlit\server.py", line 181, in get_build_dir
    raise FileNotFoundError(f"{local_target} built UI dir not found")
FileNotFoundError: frontend built UI dir not found

To Reproduce
Follow the steps listed in CONTRIBUTING.md

Expected behavior
Expected to successfully run the backend

Desktop (please complete the following information):

• OS: Windows 10
• Version: 1.3.1

[dokterbob]

Thanks for reporting this! Always important to make sure dev's don't run into trouble!

I'll have to test this myself. Until then, perhaps #1500 is related?

@dosu Any idea what's going on?

[dosubot]

The error you're encountering, FileNotFoundError: frontend built UI dir not found, indicates that the frontend build directory is missing. Here are the steps to resolve this issue:

1. Check the Build Directory: Ensure that the "dist" directory exists in the expected location. The code looks for this directory at os.path.join(PACKAGE_ROOT, "frontend", "dist") and os.path.join(BACKEND_ROOT, "frontend", "dist").

2. Build the Frontend: If the directory does not exist, you need to build the frontend. Navigate to the frontend directory and run the following commands:

   pnpm install
   pnpm run dev --port 5174

   This will install the necessary dependencies and start the development server for the frontend. Make sure you have pnpm installed and configured correctly on your Windows system. You might need to set the script shell to bash using:

   pnpm config set script-shell "C:\\Program Files\\git\\bin\\bash.exe"

3. Verify Custom Build Path: If you have a custom build path specified in your configuration (config.ui.custom_build), ensure that the path is correct and the build output is present there.

Following these steps should help you resolve the error and successfully run the Chainlit server from source ^[1][2].

To continue talking to Dosu, mention @dosu.

[dokterbob]

The frontend should be built when you do poetry install.

Could you share the full terminal output when this error occurs?

[PyroGenesis]

I upgraded my fork to v1.3.2 and tried the steps again.

Installing dependencies: poetry install --with tests --with mypy --with dev

PS C:\Projects - Misc\chainlit\backend> poetry install --with tests --with mypy --with dev
Creating virtualenv chainlit in C:\Projects - Misc\chainlit\backend\.venv
Installing dependencies from lock file

Package operations: 186 installs, 1 update, 0 removals

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Installing the current project: chainlit (1.3.2)

Running hello.py: chainlit run .\chainlit\hello.py

(chainlit-py3.10) PS C:\Projects - Misc\chainlit\backend> chainlit run .\chainlit\hello.py
Traceback (most recent call last):
  File "C:\Projects - Misc\chainlit\backend\.venv\Scripts\chainlit", line 6, in <module>
    sys.exit(cli())
  File "C:\Projects - Misc\chainlit\backend\.venv\lib\site-packages\click\core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
  File "C:\Projects - Misc\chainlit\backend\.venv\lib\site-packages\click\core.py", line 1078, in main
    rv = self.invoke(ctx)
  File "C:\Projects - Misc\chainlit\backend\.venv\lib\site-packages\click\core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "C:\Projects - Misc\chainlit\backend\.venv\lib\site-packages\click\core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "C:\Projects - Misc\chainlit\backend\.venv\lib\site-packages\click\core.py", line 783, in invoke
    return __callback(*args, **kwargs)
  File "C:\Projects - Misc\chainlit\backend\chainlit\cli\__init__.py", line 201, in chainlit_run
    run_chainlit(target)
  File "C:\Projects - Misc\chainlit\backend\chainlit\cli\__init__.py", line 39, in run_chainlit
    from chainlit.server import app
  File "C:\Projects - Misc\chainlit\backend\chainlit\server.py", line 184, in <module>
    build_dir = get_build_dir("frontend", "frontend")
  File "C:\Projects - Misc\chainlit\backend\chainlit\server.py", line 181, in get_build_dir
    raise FileNotFoundError(f"{local_target} built UI dir not found")
FileNotFoundError: frontend built UI dir not found

I'm not so sure frontend is built on poetry install.

[dokterbob]

That's very strange. This is what it's supposed to look like, on Windows ('Install Python, poetry and Python dependencies'): https://github.com/Chainlit/chainlit/actions/runs/12168265972/job/33938703121

What version of poetry, python etc are you rocking? When you used the same versions as we do in our CI, does it resolve the problem?

[SigveSjovold]

I have the same issue, any update on this?

[C-Chafik]

Same issue here, building the frontend project does not fix it, i have to manually recreate the frontend/dict directory.

[SigveSjovold]

Same issue here, building the frontend project does not fix it, i have to manually recreate the frontend/dict directory.

Were you able to get it to work then? If so, how did you recreate the frontend/dict dir?

[C-Chafik]

Same issue here, building the frontend project does not fix it, i have to manually recreate the frontend/dict directory.

Were you able to get it to work then? If so, how did you recreate the frontend/dict dir?

Have you tried to launch pnpm buildUi after pnpm install at the root of the project ?