re-arrange Dockerfile commands to decrease image size and increase number of cache hits (localstack#4955)

Author: alexrashed

.dockerignore

@@ -1,3 +1,4 @@
+.git
 .venv*
 localstack/dashboard/web/node_modules/
 localstack/infra/

Dockerfile

@@ -117,9 +117,6 @@ ENV PYTHONUNBUFFERED=1
 ENV EDGE_BIND_HOST=0.0.0.0
 ENV LOCALSTACK_HOSTNAME=localhost
 
-# Create the infra folder (will be populated later)
-RUN mkdir -p /opt/code/localstack/localstack/infra
-
 RUN mkdir /root/.serverless; chmod -R 777 /root/.serverless
 
 # add trusted CA certificates to the cert store
@@ -178,9 +175,6 @@ RUN make freeze > requirements-runtime.txt
 # remove localstack (added as a transitive dependency of localstack-ext)
 RUN (virtualenv .venv && source .venv/bin/activate && pip3 uninstall -y localstack)
 
-# add the results of `make init` to the container. `make init` _needs_ to be executed before building this docker image.
-ADD localstack/infra/ localstack/infra/
-
 
 
 # base-light: Stage which does not add additional dependencies (like elasticsearch)
@@ -251,16 +245,19 @@ RUN mkdir -p /.npm && \
     useradd -ms /bin/bash localstack && \
     ln -s `pwd` /tmp/localstack_install_dir
 
+# Install the latest version of awslocal globally
+RUN pip3 install --upgrade awscli awscli-local requests
+
 # Add the code in the last step
+# Also adds the results of `make init` to the container.
+# `make init` _needs_ to be executed before building this docker image (since the execution needs docker itself).
 ADD localstack/ localstack/
 
 # Download some more dependencies (make init needs the LocalStack code)
-# FIXME the init python code should be independent and executed in the builder stage
+# FIXME the init python code should be independent (i.e. not depend on the localstack code), idempotent/reproducible,
+#       modify only folders outside of the localstack package folder, and executed in the builder stage.
 RUN make init
 
-# Install the latest version of awslocal globally
-RUN pip3 install --upgrade awscli awscli-local requests
-
 # Install the latest version of localstack-ext and generate the plugin entrypoints
 RUN (virtualenv .venv && source .venv/bin/activate && \
       pip3 install --upgrade localstack-ext localstack-plugin-loader)

Makefile

@@ -70,16 +70,20 @@ docker-image-stats: 	  ## TODO remove when image size is acceptable
 	docker image inspect $(IMAGE_NAME_FULL) --format='{{.Size}}'
 	docker history $(IMAGE_NAME_FULL)
 
-TAG ?= $(IMAGE_NAME_FULL)	# By default we export the full image
-EXPORT_SUFFIX ?=			# By default we use no suffix
+# By default we export the full image
+TAG ?= $(IMAGE_NAME_FULL)
+# By default we use no suffix
+EXPORT_SUFFIX ?=
 docker-save-image: 		  ## Export the built Docker image
 	docker save $(TAG) -o target/localstack-docker-image$(EXPORT_SUFFIX)-$(PLATFORM).tar
 
 docker-save-image-light:
 	make EXPORT_SUFFIX="-light" TAG=$(IMAGE_NAME_LIGHT) docker-save-image
 
-TAG ?= $(IMAGE_NAME_FULL)      # By default we build the full image
-DOCKER_BUILD_FLAGS ?= "--load" # By default we load the result to the docker daemon
+# By default we export the full image
+TAG ?= $(IMAGE_NAME_FULL)
+# By default we load the result to the docker daemon
+DOCKER_BUILD_FLAGS ?= "--load"
 docker-build: 			  ## Build Docker image
 	# prepare
 	test -e 'localstack/infra/stepfunctions/StepFunctionsLocal.jar' || make init