debian: add generate_build_dep.sh to vendor erlang dependencies

To build on OBS the source package must include all dependencies.
Downloading dependencies isn't allowed. generate_build_dep.sh will
download all dependencies.
The jenkins job to update OBS should do this before calling
`dpkg-buildpackage -S` to build a source package.

Related: SYS#6006
Change-Id: I22041887fd1b72ea328605d18801d412b86bfc9c

contrib/generate_build_dep.sh

@@ -0,0 +1,17 @@
+#!/bin/sh -e
+
+# execute the script from the top dir of this repository to generate
+# a build_dep.tar.gz for building with debian/OBS
+
+if [ ! -e rebar.config ] ; then
+	echo "Please execute $0 from the top directory of the osmo_dia2gsup directory"
+	exit 1
+fi
+
+set -x
+rm -rf _checkouts _build
+rebar3 get-deps
+mkdir _checkouts
+mv ./_build/default/lib/* _checkouts/
+mv ./_build/default/plugins/* _checkouts/
+tar czf build_dep.tar.gz ./_checkouts

debian/rules

@@ -9,10 +9,11 @@ export ERL_COMPILER_OPTIONS=deterministic
 
 override_dh_auto_build:
 	dh_auto_build
+	if [ -e build_dep.tar.gz ] ; then tar xzf ./build_dep.tar.gz ; fi
 	rebar3 compile
 	rebar3 escriptize
 	rebar3 eunit
 
 override_dh_clean:
 	dh_clean
-	rm -rf _build
+	rm -rf _build _checkouts