Added DNS Service to Blockcore.Node (#176)

Author: turcol

src/Node/Blockcore.Node/Blockcore.Node.csproj

@@ -18,6 +18,7 @@
     <ProjectReference Include="..\..\Networks\Stratis\Blockcore.Networks.Stratis\Blockcore.Networks.Stratis.csproj" />
     <ProjectReference Include="..\..\Networks\x42\x42\x42.Networks.csproj" />
     <ProjectReference Include="..\..\Networks\Xds\Blockcore.Networks.Xds\Blockcore.Networks.Xds.csproj" />
+    <ProjectReference Include="..\..\Features\Blockcore.Features.Dns\Blockcore.Features.Dns.csproj" />    
     <ProjectReference Include="..\..\Features\Blockcore.Features.NodeHost\Blockcore.Features.NodeHost.csproj" />
     <ProjectReference Include="..\..\Features\Blockcore.Features.BlockStore\Blockcore.Features.BlockStore.csproj" />
     <ProjectReference Include="..\..\Features\Blockcore.Features.ColdStaking\Blockcore.Features.ColdStaking.csproj" />

src/Node/Blockcore.Node/NodeBuilder.cs

@@ -9,6 +9,7 @@
 using Blockcore.Features.RPC;
 using Blockcore.Features.Wallet;
 using Blockcore.Features.NodeHost;
+using Blockcore.Features.Dns;
 
 namespace Blockcore.Node
 {
@@ -48,7 +49,21 @@ private static IFullNodeBuilder CreateBaseBuilder(string chain, NodeSettings set
             .AddRPC()
             .UseDiagnosticFeature();
 
+            UseDnsFullNode(nodeBuilder, settings);
+
             return nodeBuilder;
         }
+        static void UseDnsFullNode(IFullNodeBuilder nodeBuilder, NodeSettings nodeSettings)
+        {
+            if (nodeSettings.ConfigReader.GetOrDefault("dnsfullnode", false, nodeSettings.Logger))
+            {
+                var dnsSettings = new DnsSettings(nodeSettings);
+
+                if (string.IsNullOrWhiteSpace(dnsSettings.DnsHostName) || string.IsNullOrWhiteSpace(dnsSettings.DnsNameServer) || string.IsNullOrWhiteSpace(dnsSettings.DnsMailBox))
+                    throw new ConfigurationException("When running as a DNS Seed service, the -dnshostname, -dnsnameserver and -dnsmailbox arguments must be specified on the command line.");
+
+                nodeBuilder.UseDns();
+            }
+        }        
     }
 }