Properly build Puma, and other native gems, inside the container

This doesn't end up as big as I feared, so I'm rather pleased.

Fixes #3

Dockerfile

@@ -1,13 +1,12 @@
 FROM ruby:2.3-alpine
 
+ARG BUILD_PKGS="ruby-dev openssl-dev gcc make libc-dev binutils"
 ARG APP_DIR=/webapp
 
 RUN mkdir -p ${APP_DIR}/vendor
 
 WORKDIR ${APP_DIR}
 
-ADD vendor/ ${APP_DIR}/vendor/
-
 ENV GEM_HOME=${APP_DIR}/vendor/gems
 ENV BUNDLE_PATH=${APP_DIR}/vendor/gems
 ENV BUNDLE_APP_CONFIG=${APP_DIR}/vendor/gems/.bundle
@@ -18,4 +17,10 @@ ADD app/ ${APP_DIR}/app/
 ADD config.ru ${APP_DIR}/
 ADD views ${APP_DIR}/views/
 ADD assets ${APP_DIR}/assets/
-CMD bundle exec rackup -o 0.0.0.0
+
+RUN apk add -U ${BUILD_PKGS} && \
+        bundle install && \
+        apk del ${BUILD_PKGS} && \
+        rm -rf /var/cache/apk/*
+
+CMD bundle exec puma

Gemfile

@@ -1,10 +1,11 @@
 source 'https://rubygems.org'
 
 gem 'haml'
-gem 'sinatra'
+gem 'httparty'
+gem 'puma'
 gem 'sentry-raven'
 gem 'sentry-api'
-gem 'httparty'
+gem 'sinatra'
 
 group :test do
   gem 'rspec'

Gemfile.lock

@@ -17,6 +17,7 @@ GEM
     multi_xml (0.6.0)
     multipart-post (2.0.0)
     mustermann (1.0.1)
+    puma (3.10.0)
     rack (2.0.3)
     rack-protection (2.0.0)
       rack
@@ -51,6 +52,7 @@ PLATFORMS
 DEPENDENCIES
   haml
   httparty
+  puma
   rspec
   sentry-api
   sentry-raven

Makefile

@@ -1,16 +1,19 @@
 
 all: check container
 
-check: depends spec
+check: spec check-container
 
-spec:
+spec: depends
 	./scripts/ruby bundle exec rspec -c
 
 depends: Gemfile
 	./scripts/ruby bundle install
 
 run: depends
-	./scripts/ruby bundle exec rackup -o 0.0.0.0
+	./scripts/ruby bundle exec puma
+
+check-container: container
+	docker run --rm rtyler/codevalet-canary:latest bundle exec puma --version
 
 container: depends Dockerfile
 	docker build -t rtyler/codevalet-canary .
@@ -18,4 +21,4 @@ container: depends Dockerfile
 clean:
 	rm -rf vendor
 
-.PHONY: all depends clean run check container spec
+.PHONY: all depends clean run check container spec check-container