optimize installation process

Author: beevelop

Dockerfile

@@ -4,16 +4,15 @@ MAINTAINER Maik Hummel <m@ikhummel.com>
 # Build-Variables
 ENV NODEJS_VERSION 5.0.0
 
-# Set Environment Variables
-ENV PATH $PATH:/opt/nodejs/bin
+# Set PATH variable
+ENV PATH $PATH:/opt/node/bin
 
-WORKDIR "/opt"
+WORKDIR "/opt/node"
 
-RUN curl -O https://nodejs.org/dist/v${NODEJS_VERSION}/node-v${NODEJS_VERSION}-linux-x64.tar.gz && \
+RUN apt-get update && apt-get install -y curl ca-certificates --no-install-recommends && \
 
-    # Extract and move to /opt
-    tar xf node-v${NODEJS_VERSION}-linux-x64.tar.gz && \
-    mv node-v${NODEJS_VERSION}-linux-x64 /opt/nodejs && \
-
-    # Clean up
-    rm node-v${NODEJS_VERSION}-linux-x64.tar.gz
+    curl -sL https://nodejs.org/dist/v${NODEJS_VERSION}/node-v${NODEJS_VERSION}-linux-x64.tar.gz | tar xz --strip-components=1 && \
+    
+    # clean up
+    rm -rf /var/lib/apt/lists/* && \
+    apt-get clean