Use Makefile to label Docker image and add version file.

Makefile

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+default: build
+
+# Build Docker image
+build: docker_build output
+
+# Build and push Docker image
+release: docker_build docker_push output
+
+# Image and binary can be overidden with env vars.
+DOCKER_IMAGE ?= microscaling/microscaling-demo
+
+# Get the latest commit.
+GIT_COMMIT = $(strip $(shell git rev-parse --short HEAD))
+
+# Get the version number from the code
+CODE_VERSION = $(strip $(shell cat VERSION))
+
+# Find out if the working directory is clean
+GIT_NOT_CLEAN_CHECK = $(shell git status --porcelain)
+ifneq (x$(GIT_NOT_CLEAN_CHECK), x)
+DOCKER_TAG_SUFFIX = "-dirty"
+endif
+
+# If we're releasing to Docker Hub, and we're going to mark it with the latest tag, it should exactly match a version release
+ifeq ($(MAKECMDGOALS),release)
+# Use the version number as the release tag.
+DOCKER_TAG = $(CODE_VERSION)
+
+ifndef CODE_VERSION
+$(error You need to create a VERSION file to build a release)
+endif
+
+# See what commit is tagged to match the version
+VERSION_COMMIT = $(strip $(shell git rev-list $(CODE_VERSION) -n 1 | cut -c1-7))
+ifneq ($(VERSION_COMMIT), $(GIT_COMMIT))
+$(error echo You are trying to push a build based on commit $(GIT_COMMIT) but the tagged release version is $(VERSION_COMMIT))
+endif
+
+# Don't push to Docker Hub if this isn't a clean repo
+ifneq (x$(GIT_NOT_CLEAN_CHECK), x)
+$(error echo You are trying to release a build based on a dirty repo)
+endif
+
+else
+# Add the commit ref for development builds. Mark as dirty if the working directory isn't clean
+DOCKER_TAG = $(CODE_VERSION)-$(GIT_COMMIT)$(DOCKER_TAG_SUFFIX)
+endif
+
+docker_build: $(BINARY)
+	# Build Docker image
+	docker build \
+  --build-arg VCS_URL=`git config --get remote.origin.url` \
+  --build-arg VCS_REF=$(GIT_COMMIT) \
+  --build-arg BUILD_DATE=`date -u +"%Y-%m-%dT%H:%M:%SZ"` \
+	-t $(DOCKER_IMAGE):$(DOCKER_TAG) .
+
+docker_push:
+	# Tag image as latest
+	docker tag $(DOCKER_IMAGE):$(DOCKER_TAG) $(DOCKER_IMAGE):latest
+
+	# Push to DockerHub
+	docker push $(DOCKER_IMAGE):$(DOCKER_TAG)
+	docker push $(DOCKER_IMAGE):latest
+
+output:
+	@echo Docker Image: $(DOCKER_IMAGE):$(DOCKER_TAG)

VERSION

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+v1.4.0