DnsResolver refactoring.

Imported Wokhan UI libs and helpers (manually, will add them to github / nuget soon). Note: Looks like the icons are not showing up properly everytime in the Connections page. Double check required.
jasonyongwang · Mar 10, 2020 · 50c3636 · 50c3636
1 parent c5c3b8f
commit 50c3636
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Showing 12 changed files with 114 additions and 187 deletions.
diff --git a/Common/Common.csproj b/Common/Common.csproj
@@ -39,6 +39,11 @@
     <PackageReference Include="System.Management" Version="4.7.0" />
     <PackageReference Include="System.ServiceProcess.ServiceController" Version="4.7.0" />
   </ItemGroup>
+  <ItemGroup>
+    <Reference Include="Wokhan.Core">
+      <HintPath>..\TempSharedLib\Wokhan.Core.dll</HintPath>
+    </Reference>
+  </ItemGroup>
   <ItemGroup>
     <Resource Include="Resources\Shield.ico" />
   </ItemGroup>

diff --git a/Common/Net/Dns/DnsResolver.cs b/Common/Net/Dns/DnsResolver.cs
@@ -1,8 +1,10 @@
 using System;
 using System.Collections.Generic;
+using System.Collections.Specialized;
 using System.Linq;
 using System.Net;
 using System.Threading.Tasks;
+using Wokhan.Collections;
 using Wokhan.WindowsFirewallNotifier.Common.Helpers;
 
 /// <summary>
@@ -20,111 +22,83 @@ public static class DnsResolver
         /// <summary>
         /// Dictionary of resolved IP addresses.
         /// </summary>
-        public static readonly Dictionary<IPAddress, CachedIPHostEntry> CachedIPHostEntryDict = new Dictionary<IPAddress, CachedIPHostEntry>();
-
-        public static async Task ResolveIpAddresses(IEnumerable<string> ipAddressList, int maxEntriesToResolve = 1000)
-        {
-            if (ipAddressList == null)
-            {
-                return;
-            }
-
-            var ipList = ipAddressList.Select(s => IPAddress.TryParse(s, out IPAddress parsedIP) ? parsedIP : LogHelper.WarnAndReturn<IPAddress>($"Cannot parse IP {s}", null));
-
-            await ResolveIpAddresses(ipList, maxEntriesToResolve).ConfigureAwait(false);
-        }
-        /// <summary>
-        /// Resolves given ip addresses to IPHostEntry and stores them in CachedIPHostEntryDict.
-        /// </summary>
-        /// <param name="ipAddressList">IP address list to resolve</param>
-        /// <param name="maxEntriesToResolve">Max entries to resolve for this task</param>
-        /// <returns></returns>
-        public static async Task ResolveIpAddresses(IEnumerable<IPAddress> ipAddressList, int maxEntriesToResolve = 1000)
-        {
-            await Task.Run(() =>
-            {
-                ipAddressList.Take(maxEntriesToResolve)
-                             .AsParallel()
-                             .ForAll(ip => ResolveIP(ip));
-            }).ConfigureAwait(false);
-        }
+        public static readonly ObservableDictionary<IPAddress, CachedIPHostEntry> CachedIPHostEntryDict = new ObservableDictionary<IPAddress, CachedIPHostEntry>();
 
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1031:Do not catch general exception types", Justification = "<Pending>")]
-        public static async Task<CachedIPHostEntry> ResolveIpAddress(string ip)
+        public static async void ResolveIpAddress(string ip, Action<CachedIPHostEntry> updateRemoteHostNameCallback)
         {
-            return await Task.Run(() =>
+            await Task.Run(() =>
             {
                 if (!IsIPValid(ip))
                 {
-                    return CachedIPHostEntry.EMTPY;
+                    updateRemoteHostNameCallback(CachedIPHostEntry.EMTPY);
+                    return;
                 }
                 IPAddress ipa = null;
                 try
                 {
                     ipa = IPAddress.Parse(ip);
-                    ResolveIP(ipa);
-                    return CachedIPHostEntryDict[ipa];
-                } catch (Exception e)
-                {
-                    return CachedIPHostEntry.CreateErrorEntry(ipa, e);
-                }
-            }).ConfigureAwait(false);
-        }
 
-        internal static bool IsIPValid(string ip) => !string.IsNullOrWhiteSpace(ip) && ip != "0.0.0.0" && ip != "::" && ip != "::0";
+                    try
+                    {
+                        if (CachedIPHostEntryDict.ContainsKey(ipa))
+                        {
+                            NotifyCollectionChangedEventHandler add = (sender, args) =>
+                            {
+                                if (args.Action == NotifyCollectionChangedAction.Replace)
+                                {
+                                    var entry = (KeyValuePair<IPAddress, CachedIPHostEntry>)args.NewItems[0];
+                                    if (entry.Key == ipa)
+                                        updateRemoteHostNameCallback(entry.Value);
+                                }
+                            };
+                            CachedIPHostEntryDict.CollectionChanged += add;
+                            CachedIPHostEntryDict.CollectionChanged += (s, e) => CachedIPHostEntryDict.CollectionChanged -= add;
+                        }
+                        else
+                        {
+                            PutEntry(ipa, CachedIPHostEntry.EMTPY);  // reserve slot
+                            updateRemoteHostNameCallback(CachedIPHostEntry.EMTPY);
 
-        public static string getResolvedHostName(string ipAddress)
-        {
-            if (!IsIPValid(ipAddress))
-            {
-                return "invalid ip";
-            }
-            CachedIPHostEntryDict.TryGetValue(IPAddress.Parse(ipAddress), out CachedIPHostEntry ipHost);
-            if (ipHost == null)
-            {
-                return "unkown host";
-            }
-            return ipHost.DisplayText;
-        }
+                            // http://www.dotnetframework.org/default.aspx/4@0/4@0/DEVDIV_TFS/Dev10/Releases/RTMRel/ndp/fx/src/Net/System/Net/DNS@cs/1305376/DNS@cs
+                            IPHostEntry resolvedEntry = System.Net.Dns.GetHostEntry(ipa);
+                            var entry = new CachedIPHostEntry
+                            {
+                                HostEntry = resolvedEntry,
+                                IsResolved = true,
+                                DisplayText = resolvedEntry.HostName
+                            };
+                            PutEntry(ipa, entry);
+                        }
+                    }
+                    catch (Exception e)
+                    {
+                        PutEntry(ipa, CachedIPHostEntry.CreateErrorEntry(ipa, e));
+                    }
 
-        [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1031:Do not catch general exception types", Justification = "<Pending>")]
-        private static void ResolveIP(IPAddress ip)
-        {
-            try
-            {
-                if (!CachedIPHostEntryDict.ContainsKey(ip))
+                    updateRemoteHostNameCallback(CachedIPHostEntryDict[ipa]);
+                }
+                catch (Exception e)
                 {
-                    PutEntry(ip, CachedIPHostEntry.EMTPY);  // reserve slot
-                    // http://www.dotnetframework.org/default.aspx/4@0/4@0/DEVDIV_TFS/Dev10/Releases/RTMRel/ndp/fx/src/Net/System/Net/DNS@cs/1305376/DNS@cs
-                    IPHostEntry resolvedEntry = System.Net.Dns.GetHostEntry(address: ip);
-                    var entry = new CachedIPHostEntry
-                    {
-                        HostEntry = resolvedEntry,
-                        IsResolved = true,
-                        DisplayText = resolvedEntry.HostName
-                    };
-                    PutEntry(ip, entry);
+                    updateRemoteHostNameCallback(CachedIPHostEntry.CreateErrorEntry(ipa, e));
                 }
-            }
-            catch (Exception e)
-            {
-                PutEntry(ip, CachedIPHostEntry.CreateErrorEntry(ip, e));
-            }
+            }).ConfigureAwait(false);
         }
 
+        internal static bool IsIPValid(string ip) => !string.IsNullOrWhiteSpace(ip) && ip != "0.0.0.0" && ip != "::" && ip != "::0";
+
         private static void PutEntry(IPAddress ip, CachedIPHostEntry entry)
         {
             lock (CachedIPHostEntryDict)
             {
-                if (CachedIPHostEntryDict.ContainsKey(ip))
+                if (CachedIPHostEntryDict.TryAdd(ip, entry))
                 {
-                    CachedIPHostEntryDict[ip] = entry;
-                    LogHelper.Debug($"End resolve IPHostEntry for {ip}: IsResolved={entry.IsResolved}, HasErrors={entry.HasErrors}, ToolTipText={entry.DisplayText}");
+                    LogHelper.Debug($"Start resolve IPHostEntry for {ip}: IsResolved={entry.IsResolved}, HasErrors={entry.HasErrors}, ToolTipText={entry.DisplayText}");
                 }
                 else
                 {
-                    CachedIPHostEntryDict.Add(ip, entry);
-                    LogHelper.Debug($"Start resolve IPHostEntry for {ip}: IsResolved={entry.IsResolved}, HasErrors={entry.HasErrors}, ToolTipText={entry.DisplayText}");
+                    CachedIPHostEntryDict[ip] = entry;
+                    LogHelper.Debug($"End resolve IPHostEntry for {ip}: IsResolved={entry.IsResolved}, HasErrors={entry.HasErrors}, ToolTipText={entry.DisplayText}");
                 }
             }
         }

diff --git a/Console/Console.csproj b/Console/Console.csproj
@@ -90,6 +90,11 @@
       <CopyLocalSatelliteAssemblies>true</CopyLocalSatelliteAssemblies>
     </ProjectReference>
   </ItemGroup>
+  <ItemGroup>
+    <Reference Include="Wokhan.Core">
+      <HintPath>..\TempSharedLib\Wokhan.Core.dll</HintPath>
+    </Reference>
+  </ItemGroup>
   <ItemGroup>
     <Resource Include="version.xml" />
   </ItemGroup>