TT#29456 Restore kamailio-config-tests-stretch Dockerfile

Change-Id: I0cbd0007c03f34d5fcc302383d3859fa5941cb7a

t/Dockerfile

@@ -1,17 +1,22 @@
-# DOCKER_NAME=kamailio-config-tests-jessie
+# DOCKER_NAME=kamailio-config-tests-stretch
-FROM docker.mgm.sipwise.com/sipwise-jessie:latest
+FROM docker.mgm.sipwise.com/sipwise-stretch:latest
 
 # Important! Update this no-op ENV variable when this Dockerfile
 # is updated with the current date. It will force refresh of all
 # of the base images and things like `apt-get update` won't be using
 # old cached versions when the Dockerfile is built.
-ENV REFRESHED_AT 2018-01-18
+ENV REFRESHED_AT 2018-01-19
+
+# test execution; we need the backport of python3-junitxml from our own
+# repository since it's not part of Debian/stretch
+# files that get-code generates
+COPY t/sources.list.d/builddeps.list /etc/apt/sources.list.d/
+COPY t/sources.list.d/preferences /etc/apt/preferences.d/
 
 RUN apt-get update
 RUN apt-get install --assume-yes python-yaml python-junitxml \
-	make libtemplate-perl libyaml-perl python-pip
+  make libtemplate-perl libyaml-perl
 
-RUN pip install unittest-xml-reporting
 RUN echo './t/testrunner' >>/root/.bash_history
 
 WORKDIR /code/
@@ -22,12 +27,16 @@ WORKDIR /code/
 # When you want to build the base image from scratch
 # (jump to the next section if you don't want to build yourself!):
 #
-# % docker build --tag="kamailio-config-tests-jessie" -f t/Dockerfile .
+# you need to put the proper NGCP sources at t/sources.list.d/builddeps.list
-# % docker run --rm -i -t -v $(pwd):/code:rw kamailio-config-tests-jessie:latest bash
+# for instance, trunk:
+# echo "deb https://deb.sipwise.com/autobuild/ release-trunk-stretch main" > t/sources.list.d/builddeps.list
+#
+# % docker build --tag="kamailio-config-tests-stretch" -f t//Dockerfile .
+# % docker run --rm -i -t -v $(pwd):/code:rw kamailio-config-tests-stretch:latest bash
 #
 # Use the existing docker image:
-# % docker pull docker.mgm.sipwise.com/kamailio-config-tests-jessie
+# % docker pull docker.mgm.sipwise.com/kamailio-config-tests-stretch
-# % docker run --rm -i -t -v $(pwd):/code:rw docker.mgm.sipwise.com/kamailio-config-tests-jessie:latest bash
+# % docker run --rm -i -t -v $(pwd):/code:rw docker.mgm.sipwise.com/kamailio-config-tests-stretch:latest bash
 #
 # Inside docker (the command is in history, just press UP button):
 #   ./t/testrunner