Add a build/push/run Makefile

Dockerfile

@@ -5,8 +5,13 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
         && rm -rf /var/lib/apt/lists/*
 
 ADD run-clang-format/run-clang-format.py /usr/bin
+RUN ln -s /usr/bin/python3 /usr/local/bin/python
 
 RUN mkdir /src
 WORKDIR /src
+
+RUN echo "--- Clang-format version ---"
+RUN clang-format --version
+
 ENTRYPOINT ["run-clang-format.py"]
 

Makefile

@@ -0,0 +1,39 @@
+TAG ?= latest
+CMD ?= "-r ."
+
+DOCKER_REGISTRY = index.docker.io
+IMAGE_ORG = witekio
+IMAGE_NAME = clang-format-checker
+IMAGE_TAG = $(DOCKER_REGISTRY)/$(IMAGE_ORG)/$(IMAGE_NAME):$(TAG)
+
+WORKING_DIR := $(shell pwd)
+DOCKERFILE_DIR := $(WORKING_DIR)
+
+.DEFAULT_GOAL := build
+
+.PHONY: build push run
+
+build:: ## Build the docker image
+		@echo Building $(IMAGE_TAG)
+		@docker build --pull \
+			-t $(IMAGE_TAG) $(DOCKERFILE_DIR)
+
+push:: ## Push the docker image to the registry
+		@echo Pushing $(IMAGE_TAG)
+		@docker push $(IMAGE_TAG)
+
+run:: ## Run the docker image
+		@docker run -v $(pwd):/src -it --rm $(IMAGE_TAG) $(CMD)
+
+# A help target including self-documenting targets (see the awk statement)
+define HELP_TEXT
+Usage: make [TARGET]... [MAKEVAR1=SOMETHING]...
+
+Available targets:
+endef
+export HELP_TEXT
+help: ## This help target
+	@echo
+	@echo "$$HELP_TEXT"
+	@awk 'BEGIN {FS = ":.*?## "} /^[a-zA-Z_-]+:.*?## / \
+		{printf "\033[36m%-30s\033[0m  %s\n", $$1, $$2}' $(MAKEFILE_LIST)