When installing Rust toolchain in Docker, Bash `source` command doesn't work

Question

I am trying to create a docker image that will setup a Linux environment for building Rust projects. Here is my Dockerfile so far:

FROM ubuntu:16.04

# Update default packages
RUN apt-get update

# Get Ubuntu packages
RUN apt-get install -y \
    build-essential \
    curl

# Update new packages
RUN apt-get update

# Get Rust
RUN curl https://sh.rustup.rs -sSf | bash -s -- -y

The last thing I need to do is configure Rust, so that I can use cargo. The documentation says to use

source $HOME/.cargo/env

but when I try that in a RUN command in a Dockerfile, it says source is not recognized. Another option I found was to use

RUN /bin/bash -c "source ~/.cargo/env"

This does not error, but when I run my container, cargo is not a recognized command.

Either approach works from Bash when I have the container open, but I would like this to be automated as part of the image.

How can I integrate this into my Dockerfile?

Answer 1

You have to add the sourcing inside the .bashrc.

This works:

FROM ubuntu:16.04

# Update default packages
RUN apt-get update

# Get Ubuntu packages
RUN apt-get install -y \
    build-essential \
    curl

# Update new packages
RUN apt-get update

# Get Rust
RUN curl https://sh.rustup.rs -sSf | bash -s -- -y

RUN echo 'source $HOME/.cargo/env' >> $HOME/.bashrc

EDIT

Instead of

RUN echo 'source $HOME/.cargo/env' >> $HOME/.bashrc

you can use

ENV PATH="/root/.cargo/bin:${PATH}"

which is a less bash-only solution