Docker: setup a Lumiera build environment in a Debian/Ubuntu container

some scripting to help creating a clean build environment for testing and bugfixes

 * build_lumiera-build-dependencies.sh
   All necessary steps to prepare a pristine Debian/Ubuntu/xx distro
   for building Lumiera from source.
   + install the GPG pub key to trust
   + install a Lumiera DEP Repository to get the sources from
   + install build-essential
   + prepare, build and install NoBug
   + prepare, build and install libGDLmm
   + install the Lumiera build-dependencies from the DEB package
   At that point, you should be able to start the build just with `scons`

 * docker_open-lumiera-buildenv.sh
   Additional bash magic to launch a docker container and inject the
   build_lumiera-build-dependencies.sh script into an interactive shell

admin/README.deb.lumiera.org.PUB.gpg

@@ -0,0 +1,5 @@
+This is the Public Key of the Package signing GPG key
+used for building of Debian DEB packages on Lumiera.org
+
+Fingerprint: D0333C21252B66D54A4CC1D265B66B07A1DE94B2
+UID: Hermann Vosseler <deb@ichthyostega.de>

admin/build_lumiera-build-dependencies.sh

@@ -0,0 +1,61 @@
+#!/bin/sh
+#
+# build_lumiera-build-dependencies.sh  - prepare/build on a pristine Debian/Ubuntu system (Docker)
+#
+#
+#------------------------------------------------------Setup
+# The Debian DEB Depot to retrieve the source packages
+DEBIAN_REPO="http://lumiera.org/debian/"
+SRC_DISTRO="stretch"
+REPO_SECTION="experimental"
+#
+# GPG pubkey to trust for signed packages
+TRUSTED_GPG=$(dirname $0)/deb.lumiera.org.PUB.gpg
+#
+# Directory for building DEB packages
+PACK_DIR=./pack
+#
+#------------------------------------------------------Setup(End)
+#
+fail() {
+    echo "\nFAIL: $1\n\n"
+    exit 1
+}
+
+# Sanity-Checks
+[ -f $TRUSTED_GPG ] || fail "GPG Key not found: $TRUSTED_GPG"
+mkdir -p $PACK_DIR
+[ -w $PACK_DIR ]    || fail "Unable to build. Can not write to $PACK_DIR"
+
+
+# prepare the host system with Lumiera package sources
+cp $TRUSTED_GPG /etc/apt/trusted.gpg.d/
+chmod a+r-x /etc/apt/trusted.gpg.d/$(basename $TRUSTED_GPG)
+echo "deb-src $DEBIAN_REPO $SRC_DISTRO $REPO_SECTION" > /etc/apt/sources.list.d/55-lumiera.list
+
+apt update
+apt install -y build-essential ca-certificates
+apt update
+
+# build some special build dependencies from source
+WORKDIR=$(pwd -P)
+cd $PACK_DIR
+
+echo "\n\n======= building NoBug =======\n"
+apt-get -y build-dep nobug
+apt-get source --compile nobug
+dpkg -i nobug-dev*deb libnobug*deb            || fail "installing NoBug"
+echo "\n\n======= building GDLmm =======\n"
+apt-get -y build-dep libgdlmm-3-dev
+apt-get source --compile libgdlmm-3-dev       || fail "installing GDLmm"
+dpkg -i libgdlmm-3*deb
+
+# install the build dependencies of Lumiera from DEB
+echo "\n\nInstalling Lumiera build dependencies...\n"
+apt-get -y build-dep lumiera
+
+# return to the working directory
+cd $WORKDIR
+
+echo "Build-Dependencies of Lumiera successfully installed.\n\n"
+

admin/docker_open-lumiera-buildenv.sh

@@ -0,0 +1,44 @@
+#!/bin/sh
+#
+# docker_open-lumiera-buildenv.sh  -  launch Docker container with interactive build shell
+#
+#
+#------------------------------------------------------Setup
+#
+# Working directory path on the host
+WORKDIR_HOST="/home/$USER/devel/lumi"
+#
+# bind-mount of the working dir in the container
+WORKDIR_GUEST="/lumi"
+#
+# Docker image-ID to launch
+DOCKER_IMAGE="ubuntu:bionic"
+#
+# Script code to inject into interactive shell
+COMMANDS=$(cat) <<RUN_IN_CONTAINER
+. /etc/bash.bashrc
+. ~/.bashrc
+
+alias la='ls -latr'
+
+$WORKDIR_GUEST/admin/build_lumiera-build-dependencies.sh
+
+RUN_IN_CONTAINER
+#
+#------------------------------------------------------Setup(End)
+#
+
+# Launch...
+# (1) launch the docker container
+# (2) start a bash there to process a bash commandline
+# (3) this commandline in turn launches an interactive bash
+# (4) and this interactive bash gets a startup-Shellscript to perform
+# (5) and this shellscript is read from an temporary named pipe to another shellscript
+# (6) which in turn prints the script code from the setup-variable $COMMANDS
+#
+# bash magic thanks to Jonathan Potter; see https://serverfault.com/a/586272
+#
+#
+docker run -v $WORKDIR_HOST:$WORKDIR_GUEST -it $DOCKER_IMAGE bash -c "bash --rcfile <(echo \"${COMMANDS}\" )"
+
+