Rework the proxy Makefile to download docker-compose automagically for the build

proxy/Makefile

@@ -1,26 +1,36 @@
 IMAGE_NAME=codevalet/proxy
+COMPOSE=build/docker-compose
 
 all: check
 
-check: bats container
-	docker-compose up --remove-orphans -d
+check: bats container $(COMPOSE)
+	$(COMPOSE) up --remove-orphans -d
 	./test/check-connectivity
 	./bats/bin/bats test/*.bats
 
-bats:
-	git clone --depth 1 -b v0.4.0 https://github.com/sstephenson/bats.git
-
 container: Dockerfile nginx.conf supervisord.conf
 	docker build -t $(IMAGE_NAME):latest .
 
-# Whenever the nginx.conf changes, we should down the docker-compose bits just
-# to ensure we come up with something new
-nginx.conf:
-	docker-compose down
-
-clean:
-	docker-compose down
+clean: $(COMPOSE)
+	$(COMPOSE) down
 	docker rmi $(shell docker images -q -f "reference=$(IMAGE_NAME)")
 	rm -rf bats
+	rm -rf build
 
-.PHONY: all check container clean ensure-down
+
+bats:
+	git clone --depth 1 -b v0.4.0 https://github.com/sstephenson/bats.git
+
+# Whenever the nginx.conf changes, we should down the docker-compose bits just
+# to ensure we come up with something new
+nginx.conf: $(COMPOSE)
+	$(COMPOSE) down
+
+build:
+	mkdir -p build
+build/docker-compose: build
+	(cd build && \
+	curl -sL https://github.com/docker/compose/releases/download/1.18.0/docker-compose-`uname -s`-`uname -m` -o docker-compose && \
+	chmod +x docker-compose)
+
+.PHONY: all check container clean