Update to circleCI 2.0

Update circleCI build to run on circle 2.0 and figure out
what major terraform versions this module is still compatible with.

- CircleCI will run multiple builds with the same steps, only changing
  the terraform versions from `.circleci/config.yml:L85`
- Some tweaks in the Rakefile to help detect when `terraform init` is
  required, to deal with the post terraform 0.10.x provider module
split.
- circleCI build badge, to better see when things are breaking

Author: yuhunglin

.circleci/config.yml

@@ -0,0 +1,95 @@
+version: 2
+
+common_steps: &common_steps
+ - checkout
+ - run:
+     name: "Setup cache key"
+     command: |
+       echo $TF_VERSION > /tmp/tf_version
+ - restore_cache:
+     keys:
+       - terraform-{{ checksum "/tmp/tf_version" }}
+       # if this breaks later due to some updated ruby docker version we can deal with cache-busting scenarios then.
+       - ruby-{{ checksum "/tmp/tf_version" }}-bundle
+ - run:
+     name: "Install terraform"
+     command: |
+       if [ ! -f "/tmp/terraform" ]; then
+         wget -O "/tmp/tf.zip" https://releases.hashicorp.com/terraform/${TF_VERSION}/terraform_${TF_VERSION}_linux_amd64.zip && unzip -o -d "/tmp/terraform" "/tmp/tf.zip"
+       fi
+       chmod +x /tmp/terraform/terraform
+       sudo cp /tmp/terraform/terraform /usr/local/bin/
+ - run:
+     name: "Test: terraform version"
+     command: terraform version
+ - run:
+     name: "Test: style check"
+     command: "[ $(terraform fmt -write=false | wc -l) -eq 0 ]"
+ - run:
+     name: "Test: verify plan"
+     command: |
+       bundle install
+
+       if [ "$TF_LEGACY" != "true" ]; then
+         for example in $(ls -d examples/*/); do
+           pushd $example
+           terraform init
+           popd
+         done
+       fi
+
+       bundle exec rake
+
+ - save_cache:
+     key: terraform-{{ checksum "/tmp/tf_version" }}
+     paths:
+       - /tmp/terraform
+ - save_cache:
+     key: ruby-{{ checksum "/tmp/tf_version" }}-bundle
+     paths:
+       - /usr/local/bundle
+
+jobs:
+  0.8.8:
+    docker:
+      - image: circleci/ruby
+    environment:
+      - TF_VERSION: 0.8.8
+      - TF_LEGACY: true
+    steps: *common_steps
+  0.9.11:
+    docker:
+      - image: circleci/ruby
+    environment:
+      - TF_VERSION: 0.9.11
+      - TF_LEGACY: true
+    steps: *common_steps
+  0.10.7:
+    docker:
+      - image: circleci/ruby
+    environment:
+      - TF_VERSION: 0.10.7
+    steps: *common_steps
+  0.11.5:
+    docker:
+      - image: circleci/ruby
+    environment:
+      - TF_VERSION: 0.11.5
+    steps: *common_steps
+
+workflows:
+  version: 2
+
+  some_flow:
+    jobs:
+      - 0.8.8
+      - 0.9.11
+      - 0.10.7
+      - 0.11.5
+
+
+#experimental:
+  #notify:
+    #branches:
+      #only:
+        #- master

Gemfile

@@ -1,3 +1,4 @@
 source "http://rubygems.org"
 
 gem "rake"
+gem "semantic", "~> 1.6.1"

Gemfile.lock

@@ -2,12 +2,14 @@ GEM
   remote: http://rubygems.org/
   specs:
     rake (11.1.2)
+    semantic (1.6.1)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
   rake
+  semantic (~> 1.6.1)
 
 BUNDLED WITH
-   1.11.2
+   1.12.5

README.md

@@ -1 +1,3 @@
 # Terraform AWS OpenVPN Module
+
+[![CircleCI](https://circleci.com/gh/unifio/terraform-aws-openvpn/tree/master.svg?style=svg)](https://circleci.com/gh/unifio/terraform-aws-openvpn/tree/master)

Rakefile

@@ -1,4 +1,5 @@
 require 'rake'
+require 'semantic'
 
 inputs = {
   'stack_item_label'    => 'expl-tst',
@@ -34,6 +35,10 @@ end
 desc "Remove existing local state if present"
 task :clean, [:stack] do |t, args|
   sh "cd examples/#{args['stack']} && rm -fr .terraform *.tfstate*"
+  terraform_version = `terraform version`.split("\n", 2)[0].gsub('Terraform v','')
+  if Semantic::Version.new(terraform_version) >= Semantic::Version.new("0.10.0")
+    sh "cd examples/#{args['stack']} && terraform init"
+  end
 end
 
 desc "Create execution plan"