[docker] use `--no-cache-dir` flag to `pip` in dockerfiles to save spacehonolulu

using "--no-cache-dir" flag in pip install ,make sure downloaded packages
by pip don't cached on system . This is a best practice which make sure
to fetch from repo instead of using local cached one . Further , in case
of Docker Containers , by restricting caching , we can reduce image size.
In term of stats , it depends upon the number of python packages
multiplied by their respective size . e.g for heavy packages with a lot
of dependencies it reduce a lot by don't caching pip packages.

Further , more detail information can be found at

https://medium.com/sciforce/strategies-of-docker-images-optimization-2ca9cc5719b6

Issue-ID: MULTICLOUD-1279
Signed-off-by: Pratik Raj <rajpratik71@gmail.com>
Change-Id: If01ac9167727423f65788bdf6abfd8ee0e1546cc

1 files changed, 2 insertions, 2 deletions

diff --git a/pike/vagrant/test/Dockerfile b/pike/vagrant/test/Dockerfile
index 292cb26e..a1154dc0 100644
--- a/pike/vagrant/test/Dockerfile
+++ b/pike/vagrant/test/Dockerfile
@@ -39,8 +39,8 @@ RUN apt-get update && \
     cd /opt/ && \
     unzip -q -o -B /opt/multicloud-openstack-pike.zip -d /opt/ && \
     rm -f /opt/multicloud-openstack-pike.zip && \
-    pip3 install -r /opt/pike/requirements.txt && \
-    pip3 install -r /opt/pike/uwsgi-requirements.txt && \
+    pip3 install --no-cache-dir -r /opt/pike/requirements.txt && \
+    pip3 install --no-cache-dir -r /opt/pike/uwsgi-requirements.txt && \
     apt-get --purge remove -y wget unzip gcc libssl-dev && \
     mkdir -p /var/log/onap/multicloud/openstack/pike && \
     chown onap:onap /var/log/onap -R && \