Add CONTAINER_ENGINE variable (#124)

Add CONTAINER_ENGINE variable, with docker as default
to not break existing usages

Makefile

@@ -3,6 +3,7 @@
 IMAGE_NAME := quay.io/app-sre/qontract-server
 IMAGE_TAG := $(shell git rev-parse --short=7 HEAD)
 APP_INTERFACE_PATH ?= $(shell pwd)/../../service/app-interface
+CONTAINER_ENGINE ?= $(shell which podman >/dev/null 2>&1 && echo podman || echo docker)
 SCHEMAS_PATH ?= $(shell pwd)/../qontract-schemas
 SCHEMAS_DIR := $(SCHEMAS_PATH)/schemas
 GRAPHQL_SCHEMA_DIR := $(SCHEMAS_PATH)/graphql-schemas
@@ -24,16 +25,16 @@ endif
 dev: docker-run-clean bundle docker-run
 
 bundle:
-	@docker pull $(VALIDATOR_IMAGE_NAME):$(VALIDATOR_IMAGE_TAG)
+	@$(CONTAINER_ENGINE) pull $(VALIDATOR_IMAGE_NAME):$(VALIDATOR_IMAGE_TAG)
 	mkdir -p $(BUNDLE_DIR)
-	@docker run --rm \
+	@$(CONTAINER_ENGINE) run --rm \
 		-v $(SCHEMAS_DIR):/schemas:z \
 		-v $(GRAPHQL_SCHEMA_DIR):/graphql:z \
 		-v $(DATA_DIR):/data:z \
 		-v $(RESOURCES_DIR):/resources:z \
 		$(VALIDATOR_IMAGE_NAME):$(VALIDATOR_IMAGE_TAG) \
 		qontract-bundler /schemas /graphql/schema.yml /data /resources $(GIT_COMMIT) $(GIT_COMMIT_TIMESTAMP) > $(BUNDLE_DIR)/$(BUNDLE_FILENAME)
-	@docker run --rm \
+	@$(CONTAINER_ENGINE) run --rm \
 		-v $(BUNDLE_DIR):/bundle:z \
 		$(VALIDATOR_IMAGE_NAME):$(VALIDATOR_IMAGE_TAG) \
 		qontract-validator --only-errors /bundle/$(BUNDLE_FILENAME)
@@ -42,20 +43,20 @@ run:
 	LOAD_METHOD=fs DATAFILES_FILE=$(BUNDLE_DIR)/$(BUNDLE_FILENAME) yarn run server
 
 docker-run:
-	@docker run -it --rm \
+	@$(CONTAINER_ENGINE) run -it --rm \
 		-v $(BUNDLE_DIR):/bundle:z \
 		-p 4000:4000 \
 		-e LOAD_METHOD=fs \
 		-e DATAFILES_FILE=/bundle/$(BUNDLE_FILENAME) \
 		$(IMAGE_NAME):$(IMAGE_TAG)
 
 docker-run-clean:
-	@docker ps -aq | xargs docker rm -f || true
+	@$(CONTAINER_ENGINE) ps -aq | xargs $(CONTAINER_ENGINE) rm -f || true
 
 build:
-	@docker build --pull -t $(IMAGE_NAME):latest .
-	@docker tag $(IMAGE_NAME):latest $(IMAGE_NAME):$(IMAGE_TAG)
+	@$(CONTAINER_ENGINE) build --pull -t $(IMAGE_NAME):latest .
+	@$(CONTAINER_ENGINE) tag $(IMAGE_NAME):latest $(IMAGE_NAME):$(IMAGE_TAG)
 
 push:
-	@docker --config=$(DOCKER_CONF) push $(IMAGE_NAME):latest
-	@docker --config=$(DOCKER_CONF) push $(IMAGE_NAME):$(IMAGE_TAG)
+	@$(CONTAINER_ENGINE) --config=$(DOCKER_CONF) push $(IMAGE_NAME):latest
+	@$(CONTAINER_ENGINE) --config=$(DOCKER_CONF) push $(IMAGE_NAME):$(IMAGE_TAG)