alpine/novnc/Dockerfile

# syntax = docker/dockerfile:1
FROM alpine/base
USER root

# Build ARG for additional packages to install (eg, openssh)
ARG addpkg

# Install ssh client
RUN apk add --no-cache \
    openssh-client \
    && <<-'01-init' cat >>/app/init.d/01-init.sh

# Check for client variables
if ! [ ${MYVNC_VNCSSH_HOST} ]
then
    echo "Variable MYVNC_VNCSSH_HOST is missing."
    echo "Exiting..."
    exit 1
fi
if ! [ ${MYVNC_VNCSSH_PORT} ]
then
    echo "Variable MYVNC_VNCSSH_PORT is missing."
    echo "Exiting..."
    exit 1
fi
if ! [[ ${MYVNC_VNCSSH_PORT} =~ ^[0-9]+$ ]]
then
    echo "Variable MYVNC_VNCSSH_PORT is invalid."
    echo "Exiting..."
    exit 1
fi

# Read ssh client variables hostname and port (5900, 5901, 5902, etc)
ssh ${MYVNC_VNCSSH_HOST} -L ${MYVNC_VNCLISTEN_HOST:-5900}:localhost:${MYVNC_VNCSSH_PORT} &
01-init

# Default environment
USER ${debug:-user}