Various reusable make boilerplate and targets

Makefile

# A placeholder to name the Gist

Makefile-ansible

# Base vars
SRC_ROOT := .
ANSIBLE_USER := ubuntu
ANSIBLE_KEY := key.pem
ANSIBLE_ROOT := ${SRC_ROOT}/ansible
ANSIBLE_ROLES_PATH := ${ANSIBLE_ROOT}/roles
ANSIBLE_CONFIG := ${ANSIBLE_ROOT}/ansible.cfg
ANSIBLE_VARS_BASE := ${ANSIBLE_ROOT}/vars.yml
ANSIBLE_VAULT_PASSWORD_FILE := ${ANSIBLE_ROOT}/.vault_password
export ANSIBLE_ROOT ANSIBLE_CONFIG ANSIBLE_ROLES_PATH
export ANSIBLE_VAULT_PASSWORD_FILE ANSIBLE_VARS_BASE

# An implicit guard target, used by other targets to ensure
# that environment variables are set before beginning tasks
assert-%:
	@if [ "${${*}}" = "" ]; then \
	  echo "Environment variable $* not set"; \
	  exit 1; \
	fi

provision: assert-host assert-playbook
	ansible-playbook \
   --user ${ANSIBLE_USER} \
	 --vault-password-file=${ANSIBLE_VAULT_PASSWORD_FILE} \
	 --private-key ${ANSIBLE_KEY} \
	 --inventory $$host, \
	 ${ANSIBLE_ROOT}/$$playbook.yml

# Helpers for some lightweight encryption with ansible-vault
# More info: https://docs.ansible.com/ansible/2.4/vault.html
encrypt: assert-path
	ansible-vault encrypt \
		--vault-password-file=$$ANSIBLE_VAULT_PASSWORD_FILE $$path
decrypt: assert-path
	ansible-vault decrypt \
	--vault-password-file=$$ANSIBLE_VAULT_PASSWORD_FILE $$path
secret-%:
	ansible-vault encrypt_string $* \
	--vault-password-file $$ANSIBLE_VAULT_PASSWORD_FILE

Makefile-base

#
# File for base boilerplate, meta-targets, and useful but dependency-free little helpers
#

MAKEFLAGS += --warn-undefined-variables
SHELL := bash
.SHELLFLAGS := -eu -o pipefail -c

# An implicit guard target, used by other targets to ensure
# that environment variables are set before beginning tasks
assert-%:
	@if [ "${${*}}" = "" ]; then \
	  echo "Environment variable $* not set"; \
	  exit 1; \
	fi

# `json-wrapper` target for use with pipes. example usage:
#
#   $ terraform output -json | wrapper=terraform make json-wrap
#
json-wrap: assert-wrapper
	@python -c "import os, sys, json; print json.dumps({ os.environ['wrapper']: json.loads(sys.stdin.read())})"

# `json-to-yaml` target for use with pipes. example usage:
#
#   $ terraform output -json | make json-to-yaml
#
# NB: the `default_flow_style` argument in the call to
#     yaml.safe_dump is there to prevent inlining of lists.
json-to-yaml:
	@python -c 'import sys, json, yaml; print yaml.safe_dump(json.loads(sys.stdin.read()), default_flow_style=False)'