Cannot import external libraries (LangFlow Docker)

[Dimesio]

Bug Description

I'm attempting to build a component using the spacy and transformers library to process NLP tasks. I tried to run the component and got the error that the modules were not found. I logged into the docker image and found the langflow venv under /app/.venv and tried to install both libraries to that venv, of which the install worked. Went to test the custom component I built and I still get the same import error. I have also tried moving the import statements under the build_output() function, still same result.

where do we place python libraries for use by the docker version of langflow?

Reproduction

1. create custom component
2. add "import spacy" or "import transformers" as part of the custom component code.
3. test run the component.

Expected behavior

I expected that once I installed the libraries in the docker image to be able to use them in my custom component.

Who can help?

No response

Operating System

docker

Langflow Version

1.1.1

Python Version

3.12

Screenshot

No response

Flow File

No response

[dosubot[bot]]

@Dimesio Hello there! I'm here to help you with any bugs, questions, or contributions. Let's work together to resolve any issues you're facing.

To resolve the issue of importing external libraries like spacy and transformers in Langflow's Docker environment, you need to ensure these libraries are included in the Docker image during the build process. Here’s how you can do it:

1. Modify the Dockerfile: Add the necessary libraries to the Dockerfile using Poetry. You can do this by adding lines to install the libraries using poetry add. For example:

   RUN poetry add spacy
   RUN poetry add transformers
   

   This ensures that the libraries are included in the Docker image when it is built.

2. Rebuild the Docker Image: After modifying the Dockerfile, rebuild the Docker image to include the new dependencies. You can do this by running:

   docker build -t your-image-name .
   

3. Use the Updated Image: Once the image is rebuilt, use this updated image to run your Langflow instance. This should resolve the import errors for the spacy and transformers libraries.

By following these steps, the libraries should be available in the environment where your custom components are executed.

To continue talking to Dosu, mention @dosu.

[Dimesio]

Tried that, poetry not found....

[Dimesio]

@dosu, I'm still having issues just with the import, and your guidance to use poetry didn't work (poetry isn't even installed!!!)

[dosubot[bot]]

To resolve the issue without using Poetry, you can modify the Dockerfile to install the required Python packages using pip. Here’s how you can do it:

1. Modify the Dockerfile: Add a RUN command to install the spacy and transformers libraries using pip. Locate the section in the Dockerfile where the Python environment is set up, and add the following line:

   RUN pip install spacy transformers
   

2. Rebuild the Docker Image: After modifying the Dockerfile, rebuild the Docker image to include the new dependencies. You can do this by running:

   docker build -t your-image-name .
   

3. Use the Updated Image: Once the image is rebuilt, use this updated image to run your Langflow instance. This should resolve the import errors for the spacy and transformers libraries.

By following these steps, the libraries should be available in the environment where your custom components are executed.

To continue talking to Dosu, mention @dosu.

[Dimesio]

@dosu sigh...I'm talking about langflow docker, not just in general. the command didn't work, you are building the system to use a venv at /app/.venv

[dosubot[bot]]

It seems like this issue requires a deeper look, @ogabrielluiz could you please lend your expertise?

To continue talking to Dosu, mention @dosu.

[italojohnny]

Hi @Dimesio! This issue is happening because the project uses UV to manage the virtual environment inside the Docker container. When you try to run pip install directly inside the container, it installs the libraries globally and not into the virtual environment managed by UV. As a result, the installed libraries are not recognized by the project.

To resolve this, you should use UV to install the required libraries directly into the managed virtual environment. Here's the correct command:

uv pip install spacy transformers

This ensures the libraries are installed in the correct environment and can be used by the project.

Let me know if this helps!

[Dimesio]

that helps a lot, just getting to know uv, and I can see why you use it :) thanks, that worked!