[launcher] refactor and test classiclink

in order to test classic link, we need to stub out API calls. lets factor
creating the EC2 object into a method which can be stubbed. then we add basic
specs.

lib/stemcell/launcher.rb

@@ -8,11 +8,6 @@
 
 module Stemcell
   class Launcher
-
-    REQUIRED_OPTIONS = [
-      'region'
-    ]
-
     REQUIRED_LAUNCH_PARAMETERS = [
       'chef_role',
       'chef_environment',
@@ -71,29 +66,13 @@ def initialize(opts={})
       @log.debug "creating new stemcell object"
       @log.debug "opts are #{opts.inspect}"
 
-      REQUIRED_OPTIONS.each do |req|
-        raise ArgumentError, "missing required param #{req}" unless opts[req]
-        instance_variable_set("@#{req}",opts[req])
-      end
-
-      @ec2_url = "ec2.#{@region}.amazonaws.com"
-
-      aws_configs = {:region => @region}
-      aws_configs.merge!({
-        :access_key_id     => @aws_access_key,
-        :secret_access_key => @aws_secret_key
-      }) if @aws_access_key && @aws_secret_key
-      AWS.config(aws_configs)
-
-      if opts['vpc_id']
-        puts 'using vpc tho'
-        @ec2 = AWS::VPC.new(opts['vpc_id'], :ec2_endpoint => @ec2_url)
-      else
-        @ec2 = AWS::EC2.new(:ec2_endpoint => @ec2_url)
-      end
+      raise ArgumentError, "missing required option 'region'" unless opts['region']
+      @region = opts['region']
+      @vpc_id = opts['vpc_id']
+      @aws_access_key = opts['aws_access_key']
+      @aws_secret_key = opts['aws_secret_key']
     end
 
-
     def launch(opts={})
       verify_required_options(opts, REQUIRED_LAUNCH_PARAMETERS)
 
@@ -283,7 +262,7 @@ def wait(instances)
       @log.info "all instances in running state"
     end
 
-    def verify_required_options(params,required_options)
+    def verify_required_options(params, required_options)
       @log.debug "params is #{params}"
       @log.debug "required_options are #{required_options}"
       required_options.each do |required|
@@ -296,7 +275,7 @@ def verify_required_options(params,required_options)
     def do_launch(opts={})
       @log.debug "about to launch instance(s) with options #{opts}"
       @log.info "launching instances"
-      instances = @ec2.instances.create(opts)
+      instances = ec2.instances.create(opts)
       instances = [instances] unless Array === instances
       instances.each do |instance|
         @log.info "launched instance #{instance.instance_id}"
@@ -339,12 +318,12 @@ def set_classic_link(left_to_process, classic_link)
         processed += recently_running
         errors += run_batch_operation(recently_running) do |instance|
           begin
-            result = @ec2.client.attach_classic_link_vpc({
+            result = ec2.client.attach_classic_link_vpc({
                 :instance_id => instance.id,
                 :vpc_id => classic_link['vpc_id'],
                 :groups => classic_link['security_group_ids'],
               })
-            (result.return == true) ? nil : "classic link attach request failed"
+            result.error
           rescue StandardError => e
             e
           end
@@ -358,7 +337,7 @@ def enable_termination_protection(instances)
       @log.info "enabling termination protection on instance(s)"
       errors = run_batch_operation(instances) do |instance|
         begin
-          resp = @ec2.client.modify_instance_attribute({
+          resp = ec2.client.modify_instance_attribute({
               :instance_id => instance.id,
               :disable_api_termination => {
                 :value => true
@@ -412,5 +391,29 @@ def check_errors(operation, instance_ids, errors)
         instance_ids.zip(errors).reject { |i, e| e.nil? }
       )
     end
+
+    def ec2
+      return @ec2 if @ec2
+
+      # configure AWS with creds/region
+      aws_configs = {:region => @region}
+      aws_configs.merge!({
+        :access_key_id     => @aws_access_key,
+        :secret_access_key => @aws_secret_key
+      }) if @aws_access_key && @aws_secret_key
+      AWS.config(aws_configs)
+
+      # calculate our ec2 url
+      ec2_url = "ec2.#{@region}.amazonaws.com"
+
+      if @vpc_id
+        @ec2 = AWS::VPC.new(@vpc_id, :ec2_endpoint => ec2_url)
+      else
+        @ec2 = AWS::EC2.new(:ec2_endpoint => ec2_url)
+      end
+
+      @ec2
+    end
+
   end
 end

spec/lib/stemcell/launcher_spec.rb

@@ -8,24 +8,51 @@ def initialize(id)
   def id
     @id
   end
+
+  def status
+    :running
+  end
 end
 
 class MockException < StandardError
 end
 
 describe Stemcell::Launcher do
   let(:launcher) {
-    opts = {}
-    Stemcell::Launcher::REQUIRED_OPTIONS.map { |k| opts[k] = "" }
+    opts = {'region' => 'region'}
     launcher = Stemcell::Launcher.new(opts)
     launcher
   }
   let(:operation) { 'op' }
   let(:instances) { (1..4).map { |id| MockInstance.new(id) } }
   let(:instance_ids) { instances.map(&:id) }
 
-  describe '#run_batch_operation' do
+  describe '#set_classic_link' do
+    let(:ec2) { instance_double(AWS::EC2) }
+    let(:client) { double(AWS::EC2::Client) }
+    let(:response) { instance_double(AWS::Core::Response) }
+    before do
+      allow(launcher).to receive(:ec2).and_return(ec2)
+      allow(ec2).to receive(:client).and_return(client)
+      allow(response).to receive(:error).and_return(nil)
+    end
+
+    let(:classic_link) { {'vpc_id' => 'vpc_id', 'security_group_ids' => ['sg1', 'sg2']} }
 
+    it 'invokes classic link on all of the instances' do
+      instances.each do |instance|
+        expect(client).to receive(:attach_classic_link_vpc).ordered.with(a_hash_including(
+            :instance_id => instance.id,
+            :vpc_id => classic_link['vpc_id'],
+            :groups => classic_link['security_group_ids'],
+          )).and_return(response)
+      end
+
+      launcher.send(:set_classic_link, instances, classic_link)
+    end
+  end
+
+  describe '#run_batch_operation' do
     it "raises no exception when no internal error occur" do
       errors = launcher.send(:run_batch_operation, instances) {}
       expect(errors.all?(&:nil?)).to be true