Using environment variables to set settings ~(does not work properly)~ error in documentation

I used the following Dockerfile to build an image of my streamlit app:

FROM continuumio/miniconda3:latest
WORKDIR /app
COPY . /app/
RUN conda config --add channels conda-forge \
    && conda env create -n myapp -f environment.yml \
    && rm -rf /opt/conda/pkgs/*
ENV STREAMLIT_CONFIG_SERVER_PORT=8050
CMD conda run -n myapp streamlit run app.py

However, if I try to use port forwarding to access the container, then port 8050 does not work. Conversely, if I use --server.port=8050 in the last line, it does work.

[nthmost]

Just confirming: the line of code pertaining to the syntax of env variables is here in cli.py:

envvar = "STREAMLIT_{}".format(to_snake_case(param).upper())

[gregsadetsky]

Extremely small point to anyone coming here (as I did) to see how to set a config option via an environment variable:

Don’t forget to include the config section name in the environment variable name! For example:

export STREAMLIT_RUNNER_MAGIC_ENABLED = "False"

i.e. “RUNNER” here is the same as the “[runner]” section name in the .toml file. This must be included, otherwise the environment variable will be ignored / the config option will not be set.