Upgrade pip to fetch most recent dependencies

CONTRIBUTING.md

@@ -73,9 +73,17 @@ Packetbeat:
 Some of the Beats might have extra development requirements, in which case a
 CONTRIBUTING.md file is find in the Beat directory.
 
+## Testing
+
 You can run the whole testsuite with the following command:
 
-    # make testsuite
+    $ make testsuite
+
+Running the testsuite has the following requirements:
+
+* Python >=2.7.9
+* Docker >=1.10.0
+* Docker-compose >= 1.7.0
 
 ## Dependencies
 

libbeat/Dockerfile

@@ -20,6 +20,9 @@ ENV PYTHON_ENV=/tmp/python-env
 
 RUN test -d ${PYTHON_ENV} || virtualenv ${PYTHON_ENV}
 COPY ./tests/system/requirements.txt /tmp/requirements.txt
+
+# Upgrade pip to make sure to have the most recent version
+RUN . ${PYTHON_ENV}/bin/activate && pip install -U pip
 RUN . ${PYTHON_ENV}/bin/activate && pip install -Ur /tmp/requirements.txt
 
 # Libbeat specific

libbeat/scripts/Makefile

@@ -155,6 +155,7 @@ benchmark-tests:
 .PHONY: python-env
 python-env: ${ES_BEATS}/libbeat/tests/system/requirements.txt
 	test -d ${PYTHON_ENV} || virtualenv ${PYTHON_ENV}
+	. ${PYTHON_ENV}/bin/activate && pip install --upgrade pip ; \
 	if [ -a ./tests/system/requirements.txt ] && [ ! ${ES_BEATS}/libbeat/tests/system/requirements.txt -ef ./tests/system/requirements.txt ] ; then \
 		. ${PYTHON_ENV}/bin/activate && pip install -Ur ${ES_BEATS}/libbeat/tests/system/requirements.txt -Ur ./tests/system/requirements.txt ; \
 	else \

libbeat/tests/system/requirements.txt

@@ -1,6 +1,5 @@
+pip
 nose
 jinja2
 PyYAML
 nose-timer
-pip
-