warden: Move address release delay logic to NetworkPool

Change-Id: I9f7fee68bd37df5515f239e68b45a5d459e43f1d

warden/lib/warden/container/base.rb

@@ -66,11 +66,7 @@ module Warden
         # Release resources required for every container instance.
         def release(resources)
           if network = resources.delete(:network)
-              # Release network after some time to make sure the kernel has
-              # time to clean up things such as lingering connections.
-              ::EM.add_timer(5) {
-                network_pool.release(network)
-              }
+            network_pool.release(network)
           end
         end
 

warden/lib/warden/network.rb

@@ -9,11 +9,11 @@ module Warden
       include Comparable
 
       def <=>(other)
-        v <=> other.v
+        v <=> Octets.new(other).v
       end
 
       def eql?(other)
-        v == other.v
+        v == Octets.new(other).v
       end
 
       def hash

warden/lib/warden/pool/network_pool.rb

@@ -8,19 +8,33 @@ module Warden
 
       attr_reader :netmask
 
-      def initialize(start_address, count)
+      # The release delay can be used to postpone address being acquired again
+      # after being released. This can be used to make sure the kernel has time
+      # to clean up things such as lingering connections.
+
+      def initialize(start_address, count, options = {})
+        @start_address = Warden::Network::Address.new(start_address)
         @netmask = Network::Netmask.new(255, 255, 255, 252)
         @pool = count.times.map { |i|
-          start_address + @netmask.size * i
+          [Time.mktime(1970), @start_address + @netmask.size * i]
         }
+
+        @release_delay = options[:release_delay] || 5
       end
 
       def acquire
-        @pool.shift
+        time, address = @pool.first
+
+        if time && time < Time.now
+          @pool.shift
+          return address
+        end
+
+        return nil
       end
 
       def release(address)
-        @pool.push address
+        @pool.push [Time.now + @release_delay, address]
       end
     end
   end

warden/spec/pool/network_pool_spec.rb

@@ -0,0 +1,32 @@
+require "spec_helper"
+
+describe Warden::Pool::NetworkPool do
+
+  before(:each) do
+    @options = { :release_delay => 0.01 }
+    @network_pool = Warden::Pool::NetworkPool.new("127.0.0.0", 2, @options)
+  end
+
+  it "holds as many addresses as specified" do
+    @network_pool.acquire.should == "127.0.0.0"
+    @network_pool.acquire.should == "127.0.0.4"
+    @network_pool.acquire.should be_nil
+  end
+
+  it "delays releasing addresses" do
+    a1 = @network_pool.acquire
+    a2 = @network_pool.acquire
+
+    # Release a1
+    @network_pool.release(a1)
+
+    # Verify it cannot be acquired
+    @network_pool.acquire.should be_nil
+
+    # Sleep until the release delay has passed
+    sleep @options[:release_delay]
+
+    # Verify it can be acquired
+    @network_pool.acquire.should == a1
+  end
+end