Updated build script

build.sh

@@ -1,17 +1,69 @@
 #!/usr/bin/env bash
 set -o errexit
 
-# Set the image name
-IMAGE_NAME="phlak/mumble"
+## PRE-RUN SETUP & CONFIGURATION
+########################################
 
-# Set script directory path
 SCRIPT_DIR="$(dirname $(readlink -f ${0}))"
 
-# Set image tag
+IMAGE_NAME="phlak/mumble"
 TAG="$(grep 'ENV MUMBLE_VERSION' Dockerfile | awk '{print $3}')"
 
-# Build the image
-docker build --force-rm --pull --tag ${IMAGE_NAME}:${TAG} ${SCRIPT_DIR}
+## SCRIPT USAGE
+########################################
+
+function usageShort() {
+    echo "Usage: $(basename ${0}) [OPTIONS]"
+}
+
+function usageLong() {
+
+    usageShort
+
+	cat <<-EOF
+
+	    OPTIONS:
+
+	        -h, --help     Print this help dialogue
+	        -p, --purge    Purge the image after build
+
+	EOF
+
+}
+
+## OPTION / PARAMATER PARSING
+########################################
+
+PARSED_OPTIONS=$(getopt -n "${0}" -o hp -l "help,purge" -- "$@")
+
+eval set -- "${PARSED_OPTIONS}"
+
+while true; do
+    case "${1}" in
+        -h|--help)  usageLong; exit ;;
+        -p|--purge) PURGE=true; shift ;;
+        --)         shift; break ;;
+    esac
+done
+
+## SCRIPT FUNCTIONS
+########################################
+
+function buildImage() {
+    docker build --force-rm --pull --tag ${IMAGE_NAME}:${TAG} ${SCRIPT_DIR}
+}
+
+function purgeImage() {
+    docker rmi --force ${IMAGE_NAME}:${TAG}
+    echo "Purged image: ${IMAGE_NAME}:${TAG}"
+}
+
+function main() {
+    buildImage; [[ "${PURGE}" == true ]] && purgeImage
+    echo "Successfully built ${IMAGE_NAME}:${TAG}"
+}
+
+# MAKE IT SO
+########################################
 
-# Notify user of success
-echo "Sucessfully created image: ${IMAGE_NAME}:${TAG}"
+main