Librosa raised OSError('sndfile library not found') in Docker

Question

I'm trying to write the Dockerfile for a small python web project and there is something wrong with the dependencies. I've been doing some search on the internet and it said that Librosa library requires libsndfile to work properly so I tried to install it using apt-get install libsndfile1 (I've also tried libsndfile-dev,...) . However, it doesn't seem to solve my problem.

This is how my Dockerfile looks like:

FROM python:3.6-buster as build

ENV STATIC_URL /static
ENV STATIC_PATH /var/www/app/static

WORKDIR /var/www/

RUN python -m venv /opt/venv

ENV PATH="/opt/venv/bin:$PATH"

COPY requirements.txt .

RUN pip install -r requirements.txt

RUN pip install gunicorn

RUN apt-get update -y && apt-get install -y --no-install-recommends build-essential gcc \
                                        libsndfile1 

FROM python:3.6-buster AS run

COPY --from=build /opt/venv /opt/venv

COPY . .

ENV PATH="/opt/venv/bin:$PATH"

RUN gunicorn -b :5000 --access-logfile - --error-logfile - app:app

However, when i try to build and run this, this error occured:

[2020-04-15 17:30:02 +0000] [7] [INFO] Starting gunicorn 20.0.4
[2020-04-15 17:30:02 +0000] [7] [INFO] Listening at: http://0.0.0.0:5000 (7)
[2020-04-15 17:30:02 +0000] [7] [INFO] Using worker: sync
[2020-04-15 17:30:02 +0000] [10] [INFO] Booting worker with pid: 10
[2020-04-15 17:30:03 +0000] [10] [ERROR] Exception in worker process
Traceback (most recent call last):
  File "/opt/venv/lib/python3.6/site-packages/gunicorn/arbiter.py", line 583, in spawn_worker
    worker.init_process()
  File "/opt/venv/lib/python3.6/site-packages/gunicorn/workers/base.py", line 119, in init_process
    self.load_wsgi()
  File "/opt/venv/lib/python3.6/site-packages/gunicorn/workers/base.py", line 144, in load_wsgi
    self.wsgi = self.app.wsgi()
  File "/opt/venv/lib/python3.6/site-packages/gunicorn/app/base.py", line 67, in wsgi
    self.callable = self.load()
  File "/opt/venv/lib/python3.6/site-packages/gunicorn/app/wsgiapp.py", line 49, in load
    return self.load_wsgiapp()
  File "/opt/venv/lib/python3.6/site-packages/gunicorn/app/wsgiapp.py", line 39, in load_wsgiapp
    return util.import_app(self.app_uri)
  File "/opt/venv/lib/python3.6/site-packages/gunicorn/util.py", line 358, in import_app
    mod = importlib.import_module(module)
  File "/usr/local/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/app.py", line 12, in <module>
    from emotion_model.test import load_model, inference_segment
  File "/emotion_model/test.py", line 9, in <module>
    import librosa
  File "/opt/venv/lib/python3.6/site-packages/librosa/__init__.py", line 12, in <module>
    from . import core
  File "/opt/venv/lib/python3.6/site-packages/librosa/core/__init__.py", line 126, in <module>
    from .audio import *  # pylint: disable=wildcard-import
  File "/opt/venv/lib/python3.6/site-packages/librosa/core/audio.py", line 10, in <module>
    import soundfile as sf
  File "/opt/venv/lib/python3.6/site-packages/soundfile.py", line 142, in <module>
    raise OSError('sndfile library not found')
OSError: sndfile library not found
[2020-04-15 17:30:03 +0000] [10] [INFO] Worker exiting (pid: 10)
[2020-04-15 17:30:03 +0000] [7] [INFO] Shutting down: Master
[2020-04-15 17:30:03 +0000] [7] [INFO] Reason: Worker failed to boot.

Answer 1

For those who come to this post to find a solution. My workaround was to put the installation of libsndfile after this part:

FROM python:3.6-buster AS run

COPY --from=build /opt/venv /opt/venv

COPY . .

ENV PATH="/opt/venv/bin:$PATH"

which would be:

FROM python:3.6-buster AS run

COPY --from=build /opt/venv /opt/venv

COPY . .

ENV PATH="/opt/venv/bin:$PATH"

RUN apt-get update -y && apt-get install -y --no-install-recommends build-essential gcc \
                                        libsndfile1 

RUN gunicorn -b :5000 --access-logfile - --error-logfile - app:app