tests: pin python dependencies

This commit ensures that the tests always run with the exact same
version for all the Python dependencies. It uses pip-tools to achieve
that.

Our top-level dependencies are specified in the requirements.txt file.
From this file, pip-tools generates the requirements-{2,3}.txt file,
which pins all the versions of all the recursive dependencies, and is
used to install the packages in the test virtualenv.

To change or add a top-level dependency, update requirements.txt and run
make test as usual with python2 and python3. The requirements-{2,3}.txt
file will be updated and you can verify that nothing breaks. Then add
all requirements* files in your commit.

To refresh the python packages (i.e. get new versions of the recursive
dependencies, or of the dependencies that are not pinned in
requirements.txt), just run:
PYTHON=python2.7 make test-refresh-deps
PYTHON=python3.6 make test-refresh-deps
and this will update the requirements-{2,3}.txt files. Ideally we
should run this after each release.

Type: make
Change-Id: Ic533de3d06ec4019ff38f5231208da6f1025bfc7
Signed-off-by: Aloys Augustin <aloaugus@cisco.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index 31fd8816c7a..976cb19050e 100644
--- a/Makefile
+++ b/Makefile
@@ -226,6 +226,7 @@ help:
 	@echo " test-cov            - generate code coverage report for test framework"
 	@echo " test-wipe-cov       - wipe code coverage report for test framework"
 	@echo " test-checkstyle     - check PEP8 compliance for test framework"
+	@echo " test-refresh-deps   - refresh the Python dependencies for the tests"
 	@echo ""
 	@echo "Make Arguments:"
 	@echo " V=[0|1]                  - set build verbosity level"
@@ -455,6 +456,9 @@ test-wipe-cov:
 test-checkstyle:
 	@make -C test checkstyle
 
+test-refresh-deps:
+	@make -C test refresh-deps
+
 retest:
 	$(call test,vpp,vpp,retest)