dokku build with variables

gistfile1.txt

#!/bin/bash

DOCKERFILE="/home/ubuntu/dockerfiletest/Dockerfile"
ENVFILE='/home/dokku/oca/ENV'

env_list='ENV'

# itterate through ENV file to make a single line for use in Dockerfile
while read line; do
  # Remove the 'export ' at the beginning of each line
  lineenv=${line:7}
  env_list="$env_list $lineenv"
done <$ENVFILE

# Get teh dockerfile in var so we can look for the "tag"
dfile=`cat $DOCKERFILE`

if [[ "$dfile" =~ "#dokkuEnv#" ]]
then
    # use pipes instead of / for splitter b/c backslash might be used in $ENVFILE
    sed -i "s|#dokkuEnv#|${env_list}|g" "$DOCKERFILE"
fi