optimize size and time using "--no-cache-dir"

Using "--no-cache-dir" flag in pip install ,make sure dowloaded packages
by pip don't cached on system . This is a best practise which make sure
to fetch ftom repo instead of using local cached one . Further , in case
of Docker Containers , by restricing 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: APPC-1888

Signed-off-by: Pratik Raj <rajpratik71@gmail.com>
Change-Id: I41951d327bcf6bc381fc3d6e1789c33fd205d005

diff --git a/README.md b/README.md
index 7a7973c..4d90a72 100644 (file)
--- a/README.md
+++ b/README.md
@@ -100,7 +100,7 @@ Ther following steps are needed to deploy and start ONAP APPC:
 ```bash
 # Install Docker-Compose
 apt-get install python-pip
-pip install docker-compose
+pip install --no-cache-dir docker-compose
 
 # Login to Nexus Repo to pull Docker Images (this assumes that Nexus Certificate is already imported in the Host VM on /usr/local/share/ca-certificates/ path):
 docker login <DOCKER_REGISTRY_REPO> # prompts for user credentials as a way to authenticate