Docker bash prompt does not display color output
Based on VonC's answer I adding the following to my Dockerfile (which allows me to run the container without typing the environment variables on the command line every time):
ENV TERM xterm-256color
#... more stuff
CMD ["bash", "-l"]
And sure enough it works with:
docker run -it my-image:tag
For tmux
to work with color, in my ~/.tmux.conf
I need:
set -g default-terminal "screen-256color"
and for UTF-8 support in tmux
, in my ~/.bashrc
:
alias tmux='tmux -u'
My Dockerfile:
FROM fedora:26
ENV TERM xterm-256color
RUN dnf upgrade -y && \
dnf install golang tmux git vim -y && \
mkdir -p /app/go/{bin,pkg,src} && \
echo 'export GOPATH=/app/go' >> $HOME/.bashrc && \
echo 'export PATH=$PATH:$GOPATH/bin' >> $HOME/.bashrc && \
mkdir -p ~/.vim/autoload ~/.vim/bundle && \
curl -LSso ~/.vim/autoload/pathogen.vim \
https://tpo.pe/pathogen.vim && \
git clone https://github.com/farazdagi/vim-go-ide.git \
~/.vim_go_runtime && \
bash ~/.vim_go_runtime/bin/install && \
echo "alias govim='vim -u ~/.vimrc.go'" >> ~/.bashrc && \
echo "alias tmux='tmux -u'" >> ~/.bashrc && \
echo 'set -g default-terminal "screen-256color"' >> ~/.tmux.conf
CMD ["bash", "-l"]
The Dockerfile builds an image based off Fedora 26, updates it, installs a few packages (Git, Vim, golang and tmux), installs the pathogen plugin for Vim, then it installs a Git repository from here vim-go-ide and finally does a few tweaks to a few configuration files to get color and UTF-8 working fine. You just need to add persistent storage, probably mounted under /app/go.
If you have an image with all the development tools already installed, just make a Dockerfile
with ENV
statement and add the commands to modify the configuration files in a RUN
statement without the installation commands and use your base image in the FROM
statement. I prefer this solution because I'm lazy and (besides the initial setup) it saves typing when you want to run the image.
Using Vim and plugins within tmux
Adding -t is working for me:
docker exec -t vendor/bin/phpunit
Adding to VonC's answer, I made this Bash function:
drun() { # start container with the specified entrypoint and colour terminal
if [[ $# -lt 2 ]]; then
echo "drun needs 2+ arguments: image entrypoint" >&2
return
fi
docker run -ti -e "TERM=xterm-256color" "$@"
}
The OP SolomonT reports that docker run
with env
do work:
docker run --rm -it -e "TERM=xterm-256color" govim bash -l
And Fernando Correia adds in the comments:
To get both color support and make
tmux
work, I combined both examples:
docker exec -it my-container env TERM=xterm-256color script -q -c "/bin/bash" /dev/null
As chepner commented (earlier answer), .bash_profile
is sourced (itis an interactive shell), since bash_prompt
is called by .bash_profile
.
But docker issue 9299 illustrates that TERM
doesn't seem to be set right away, forcing the users to open another bash with:
docker exec -ti test env TERM=xterm-256color bash -l
You have similar color issues with issue 8755.
To illustrate/reproduce the problem:
docker exec -ti $CONTAINER_NAME tty
not a tty
The current workaround is :
docker exec -ti `your_container_id` script -q -c "/bin/bash" /dev/null
Both are supposing you have a running container first, which might not be convenient here.