check that number of instances in load balancer matches desired capacity

lib/aws-missing-tools/aws-ha-release/aws-ha-release.rb

@@ -94,9 +94,11 @@ class AwsHaRelease
   end
 
   def instances_inservice?(load_balancer)
-    load_balancer.instances.health.each do |health|
+    return false if load_balancer.instances.count != @group.desired_capacity
-      unless health[:state] == 'InService'
+
-        puts "Instance #{health[:instance].id} is currently #{health[:state]} on load balancer #{load_balancer.name}."
+    load_balancer.instances.health.each do |instance_health|
+      unless instance_health[:state] == 'InService'
+        puts "Instance #{instance_health[:instance].id} is currently #{instance_health[:state]} on load balancer #{load_balancer.name}."
 
         return false
       end

spec/aws-missing-tools/aws-ha-release/aws-ha-release_spec.rb

@@ -14,6 +14,10 @@ describe 'aws-ha-release' do
 
   let(:as) { AWS::FakeAutoScaling.new }
 
+  let(:instance_one) { AWS::FakeEC2::Instance.new }
+
+  let(:instance_two) { AWS::FakeEC2::Instance.new }
+
   before do
     AWS::AutoScaling.stub(:new).and_return(as)
     IO.any_instance.stub(:puts)
@@ -71,47 +75,82 @@ describe 'aws-ha-release' do
   describe 'determining if instances are in service' do
     before do
       @group = as.groups.create opts[:as_group_name]
+      @group.update(desired_capacity: 2)
       @aws_ha_release = AwsHaRelease.new(opts)
     end
 
     it 'checks all instances across a given load balancer' do
-      load_balancer = AWS::FakeELB::LoadBalancer.new 'test_load_balancer_01'
+      load_balancer = AWS::FakeELB::LoadBalancer.new 'test_load_balancer_01', [
+        {
+          instance: instance_one,
+          healthy: true
+        },
+        {
+          instance: instance_two,
+          healthy: false
+        }
+      ]
 
       expect(@aws_ha_release.instances_inservice?(load_balancer)).to eq false
 
-      load_balancer.instances.health[1] = {
+      load_balancer.instances.make_instance_healthy(instance_two)
-        instance: AWS::FakeEC2::Instance.new,
-        description: 'N/A',
-        state: 'InService',
-        reason_code: 'N/A'
-      }
-
       expect(@aws_ha_release.instances_inservice?(load_balancer)).to eq true
     end
 
     it 'checks all instances across an array of load balancers' do
-      load_balancers = [AWS::FakeELB::LoadBalancer.new('test_load_balancer_01'), AWS::FakeELB::LoadBalancer.new('test_load_balancer_02')]
+      load_balancers = [
+        AWS::FakeELB::LoadBalancer.new('test_load_balancer_01', [
+          {
+            instance: instance_one,
+            healthy: true
+          },
+          {
+            instance: instance_two,
+            healthy: false
+          }
+        ]), AWS::FakeELB::LoadBalancer.new('test_load_balancer_02', [
+          {
+            instance: instance_one,
+            healthy: true
+          },
+          {
+            instance: instance_two,
+            healthy: false
+          }
+        ])
+      ]
 
       expect(@aws_ha_release.all_instances_inservice?(load_balancers)).to eq false
 
-      load_balancers[0].instances.health[1] = {
+      load_balancers[0].instances.make_instance_healthy(instance_two)
-        instance: AWS::FakeEC2::Instance.new,
-        description: 'N/A',
-        state: 'InService',
-        reason_code: 'N/A'
-      }
-
       expect(@aws_ha_release.all_instances_inservice?(load_balancers)).to eq false
 
-      load_balancers[1].instances.health[1] = {
+      load_balancers[1].instances.make_instance_healthy(instance_two)
-        instance: AWS::FakeEC2::Instance.new,
-        description: 'N/A',
-        state: 'InService',
-        reason_code: 'N/A'
-      }
-
       expect(@aws_ha_release.all_instances_inservice?(load_balancers)).to eq true
     end
+
+    it 'requires the number of inservice instances to match the desired capacity' do
+      load_balancer = AWS::FakeELB::LoadBalancer.new 'test_load_balancer_01', [
+        {
+          instance: instance_one,
+          healthy: true
+        },
+        {
+          instance: instance_two,
+          healthy: true
+        }
+      ]
+
+      @group.update(desired_capacity: 3)
+
+      expect(@aws_ha_release.instances_inservice?(load_balancer)).to eq false
+
+      instance_three = AWS::FakeEC2::Instance.new
+      load_balancer.instances.register instance_three
+      load_balancer.instances.make_instance_healthy(instance_three)
+
+      expect(@aws_ha_release.instances_inservice?(load_balancer)).to eq true
+    end
   end
 
   describe '#deregister_instance' do
@@ -121,11 +160,26 @@ describe 'aws-ha-release' do
     end
 
     it 'deregisters an instance across all load balancers' do
-      instance_one = AWS::FakeEC2::Instance.new
+      elb_one = AWS::FakeELB::LoadBalancer.new 'test_load_balancer_01', [
-      instance_two = AWS::FakeEC2::Instance.new
+        {
-
+          instance: instance_one,
-      elb_one = AWS::FakeELB::LoadBalancer.new 'test_load_balancer_01'
+          healthy: true
-      elb_two = AWS::FakeELB::LoadBalancer.new 'test_load_balancer_02'
+        },
+        {
+          instance: instance_two,
+          healthy: true
+        }
+      ]
+      elb_two = AWS::FakeELB::LoadBalancer.new 'test_load_balancer_02', [
+        {
+          instance: instance_one,
+          healthy: true
+        },
+        {
+          instance: instance_two,
+          healthy: true
+        }
+      ]
 
       elb_one.instances.register instance_one
       elb_one.instances.register instance_two

spec/support/fake_elb.rb

@@ -4,14 +4,11 @@ module AWS
     end
 
     class LoadBalancer
-      attr_reader :name
+      attr_reader :name, :instances
 
-      def initialize(name, options = {})
+      def initialize(name, instances_and_healths)
         @name = name
-      end
+        @instances ||= InstanceCollection.new(instances_and_healths)
-
-      def instances
-        @instances ||= InstanceCollection.new
       end
     end
 
@@ -21,7 +18,15 @@ module AWS
     end
 
     class InstanceCollection < Array
-      def initialize
+      attr_reader :health
+
+      def initialize(instances_and_healths)
+        @health = []
+
+        instances_and_healths.each do |instance_and_health|
+          self << instance_and_health[:instance]
+          instance_and_health[:healthy] ? make_instance_healthy(instance_and_health[:instance]) : make_instance_unhealthy(instance_and_health[:instance])
+        end
       end
 
       def register(*instances)
@@ -34,21 +39,40 @@ module AWS
         end
       end
 
-      def health
+      def make_instance_healthy(instance)
-        @health ||= [
+        opts = {
-          {
+          instance: instance,
-            instance: AWS::FakeEC2::Instance.new,
           description: 'N/A',
           state: 'InService',
           reason_code: 'N/A'
-          },
+        }
-          {
+
-            instance: AWS::FakeEC2::Instance.new,
+        @health.each_with_index do |health, i|
+          if health[:instance] == instance
+            @health[i] = opts
+            return
+          end
+        end
+
+        @health << opts
+      end
+
+      def make_instance_unhealthy(instance)
+        opts = {
+          instance: instance,
           description: 'Instance has failed at least the UnhealthyThreshold number of health checks consecutively.',
           state: 'OutOfService',
           reason_code: 'Instance'
         }
-        ]
+
+        @health.each_with_index do |health, i|
+          if health[:instance] == instance
+            @health[i] = opts
+            return
+          end
+        end
+
+        @health << opts
       end
     end
   end