Makefile for Cloudformation templates with Jinja2 support.

Makefile

.PHONY : prereqs clean build upload
.DELETE_ON_ERROR:
.SUFFIXES:

# methods to verified variables are definied
check_defined = \
    $(strip $(foreach 1,$1, \
        $(call _check_defined,$1,$(strip $(value 2)))))
_check_defined = \
	$(if $(value $1),, \
      $(error Undefined argument $1$(if $2, ($2))))

MAKEFILE_DIR := $(abspath $(dir $(lastword $(MAKEFILE_LIST))))
MAKEFILE_PATH := $(abspath $(lastword $(MAKEFILE_LIST)))

# Directory containing source (YAML) files
source_dir := $(MAKEFILE_DIR)/src/main/yaml

# Directory containing templated YAML files
output_dir := $(MAKEFILE_DIR)/build/${BUILD_NUMBER}

# All markdown files in src/main/yaml are considered sources
sources := $(wildcard $(source_dir)/*.yaml $(source_dir)/**/*.yaml)

# Convert the list of source files
objects := $(patsubst %.yaml,%.yaml,$(subst $(source_dir),$(output_dir),$(sources)))

# Prerequsite tools, we use these variables to check they exist.
j2 := $(shell command -v j2 2> /dev/null)
yamllint := $(shell command -v yamllint 2> /dev/null)
$(call check_defined, j2, install j2 via 'pip install j2cli')
$(call check_defined, yamllint, install yamllint via 'pip install yamllint')

# Check required variables are set.
$(call check_defined, BUCKET, specify the bucket youd like to store the templates in)
$(call check_defined, BUILD_NUMBER, specify the build or git revision number)

# Targets
build: $(objects)

clean:
	$(info Cleaning $(MAKEFILE_DIR)/build...)
	@ rm -rf $(MAKEFILE_DIR)/build/

$(output_dir)/%.yaml: $(source_dir)/%.yaml
	$(info Processing $< with Jinja2...)
	@ mkdir -p $(abspath $(dir $@))
	@ yamllint $<
	@ j2 \
		-e "bucket='${BUCKET}'" \
		-e "build_number='${BUILD_NUMBER}'" \
		$< > $@

	$(info Validating $@...)
	@ aws cloudformation validate-template --template-body file://$@ >/dev/null

upload.sh

#!/usr/bin/env bash
set -euo pipefail

DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
BUILD_NUMBER=$(git -C ${DIR} describe --tags --always --dirty )

export BUILD_NUMBER
export BUCKET

# First build the templates out.
make -j 16 -C ${DIR} build

# Now upload them to S3.
aws s3 sync "${DIR}/build/${BUILD_NUMBER}" "s3://${BUCKET}/cloudformation/${BUILD_NUMBER}" \
    | sed s/s3:../https:\\/\\/s3.amazonaws.com\\//g \
    | grep -v '/resources/' \
    | sed s/upload..//g