Merge branch 'master' into fix/backup-chain/server-name

Author: AdityaNPL

src/AgDatabase.cs

@@ -12,6 +12,7 @@ namespace AgDatabaseMove
   using System.Data.SqlClient;
   using System.Linq;
   using System.Threading;
+  using Exceptions;
   using Polly;
   using SmoFacade;
 
@@ -35,6 +36,7 @@ void Restore(IEnumerable<BackupMetadata> backupOrder, Func<int, TimeSpan> retryD
     void DropAllLogins();
     void AddRole(LoginProperties login, RoleProperties role);
     IEnumerable<RoleProperties> AssociatedRoles();
+    void ContainsLogin(string loginName);
   }
 
 
@@ -233,5 +235,43 @@ public void MultiUserMode()
     {
       _listener.Primary.Database(Name).MultiUserMode();
     }
+
+    private void CheckLoginExists(Server server, AvailabilityGroup availabilityGroup, string loginName)
+    {
+      var matchingLogins = server.Logins.Where(l => l.Name == loginName);
+      
+      if (matchingLogins.Count() == 0)
+        throw new MissingLoginException($"Login missing on {server.Name}, {_listener.AvailabilityGroup.Name}, {loginName}");
+
+      if (matchingLogins.Count() > 1)
+        throw new
+          MultipleLoginException($"Multiple logins exist on {server.Name}, {_listener.AvailabilityGroup.Name}, {loginName}");
+
+      var sid = matchingLogins.First().Sid;
+      if (sid == null || sid.Length == 0)
+        throw new MissingSidException($"Sid missing on {server.Name}, {_listener.AvailabilityGroup.Name}, {loginName}");
+    }
+
+    public void ContainsLogin(string loginName)
+    {
+      var exceptions = new ConcurrentQueue<Exception>();
+
+      _listener.ForEachAgInstance((s, ag) => {
+        try {
+          CheckLoginExists(s, ag, loginName);
+        }
+        catch(MissingLoginException ex) {
+          exceptions.Enqueue(ex);
+        }
+        catch(MultipleLoginException ex) {
+          exceptions.Enqueue(ex);
+        }
+        catch(MissingSidException ex) {
+          exceptions.Enqueue(ex);
+        }
+      });
+
+      if(exceptions.Count > 0) throw new AggregateException(exceptions);
+    }
   }
 }

src/Exceptions/MissingLoginException.cs

@@ -0,0 +1,8 @@
+namespace AgDatabaseMove.Exceptions
+{
+
+  public class MissingLoginException : AgDatabaseMoveException
+  {
+    public MissingLoginException(string message) : base(message) { }
+  }
+}

src/Exceptions/MissingSidException.cs

@@ -0,0 +1,8 @@
+namespace AgDatabaseMove.Exceptions
+{
+
+  public class MissingSidException : AgDatabaseMoveException
+  {
+    public MissingSidException(string message) : base(message) { }
+  }
+}

src/Exceptions/MultipleLoginException.cs

@@ -0,0 +1,8 @@
+namespace AgDatabaseMove.Exceptions
+{
+
+  public class MultipleLoginException : AgDatabaseMoveException
+  {
+    public MultipleLoginException(string message) : base(message) { }
+  }
+}

src/SmoFacade/Login.cs

@@ -104,11 +104,15 @@ private static Microsoft.SqlServer.Management.Smo.Login ConstructLogin(LoginProp
     {
       var login = new Microsoft.SqlServer.Management.Smo.Login(server._server, loginProperties.Name) {
         LoginType = loginProperties.LoginType,
-        Sid = loginProperties.Sid,
         DefaultDatabase = loginProperties.DefaultDatabase
       };
 
-      if(loginProperties.LoginType == LoginType.SqlLogin) {
+      if (loginProperties.Sid != null)
+      {
+        login.Sid = loginProperties.Sid;
+      }
+
+      if (loginProperties.LoginType == LoginType.SqlLogin) {
         if(loginProperties.PasswordHash != null)
           login.Create(loginProperties.PasswordHash, LoginCreateOptions.IsHashed);
         else if(loginProperties.Password != null)