CA-203431: Host name is repeated twice in multipathing alert message in XC (#2272)

* CA-203431: Removed prefix comma and space from the start of the list of hosts in the multipathing alert message.

* CA-203431: Removed duplicate Host names from multipathing alert message.

* CA-203431: Unit tests for MessageAlert.FindHostUuids with tweaks to allow it to handle a null input as if it was an empty enumeration.

Signed-off-by: Aaron Robson <aaron.robson@citrix.com>

XenAdmin/Alerts/Types/MessageAlert.cs

@@ -31,6 +31,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using XenAPI;
 using XenAdmin.Actions;
 using XenAdmin.Core;
@@ -311,21 +312,28 @@ namespace XenAdmin.Alerts
             else
             {
                 // Several hosts in pool unhealthy, list their names as a summary
-                string output = "";
-                foreach (string s in currentState)
-                {
-                    Match m = multipathRegex.Match(s);
-                    if (m.Success)
-                    {
-                        output = string.Format("{0}, '{1}'", output, Message.Connection.Cache.Find_By_Uuid<Host>(m.Groups[1].Value));
-                    }
-                }
+                var output = string.Join(", ",
+                    FindHostUuids(currentState)
+                        .Select(s => string.Format("'{0}'", Message.Connection.Cache.Find_By_Uuid<Host>(s)))
+                    );
                 return string.Format(PropertyManager.GetFriendlyName("Message.body-multipath_periodic_alert_summary"),
                     Helpers.GetName(XenObject),
                     output);
             }
         }
 
+        public static IEnumerable<string> FindHostUuids(IEnumerable<string> lines)
+        {
+            if (lines == null)
+                return Enumerable.Empty<string>();
+
+            return lines
+                .Select(s => multipathRegex.Match(s))
+                .Where(m => m.Success)
+                .Select(m => m.Groups[1].Value)
+                .Distinct();
+        }
+
         private string GetManagementBondName()
         {
             Bond bond = NetworkingHelper.GetMasterManagementBond(Connection);

XenAdminTests/UnitTests/AlertTests/MultipathAlertTest.cs

@@ -0,0 +1,97 @@
+/* Copyright (c) Citrix Systems, Inc. 
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, 
+ * with or without modification, are permitted provided 
+ * that the following conditions are met: 
+ * 
+ * *   Redistributions of source code must retain the above 
+ *     copyright notice, this list of conditions and the 
+ *     following disclaimer. 
+ * *   Redistributions in binary form must reproduce the above 
+ *     copyright notice, this list of conditions and the 
+ *     following disclaimer in the documentation and/or other 
+ *     materials provided with the distribution. 
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
+ * SUCH DAMAGE.
+ */
+ 
+using System.Collections.Generic;
+using System.Linq;
+using NUnit.Framework;
+using XenAdmin.Alerts;
+
+namespace XenAdminTests.UnitTests.AlertTests
+{
+    [TestFixture, Category(TestCategories.Unit)]
+    public class MultipathAlertTest
+    {
+        [Test]
+        public void TestFindHostUuidsTestGivenNull()
+        {
+            FindHostUuidsTestHelper(null, Enumerable.Empty<string>());
+        }
+
+        [Test]
+        public void TestFindHostUuidsTestGivenMultipleWithoutDuplicates()
+        {
+            var given = new List<string>
+            {
+                "[20181016T09:55:52Z] host=0d5b647c-d913-40e0-a94f-4b9c94dd41eb; host-name=\"xrtuk-12-05\"; pbd=bf08dedc-2564-df8c-3f61-b07654cf824a; scsi_id=3600a098038303973743f486833396d41; current=2; max=4",
+                "[20181016T09:55:52Z] host=2e257cd5-b1cb-4f90-908b-e939e8730924; host-name=\"xrtuk-13-06\"; pbd=bf08dedc-2564-df8c-3f61-b07654cf824a; scsi_id=3600a098038303973743f486833396d41; current=2; max=4",
+            };
+            var expected = new List<string> { "0d5b647c-d913-40e0-a94f-4b9c94dd41eb", "2e257cd5-b1cb-4f90-908b-e939e8730924" };
+            FindHostUuidsTestHelper(given, expected);
+        }
+
+        [Test]
+        public void TestFindHostUuidsTestGivenMultipleWithDuplicates()
+        {
+            var given = new List<string>
+            {
+                "[20181016T09:55:52Z] host=2e257cd5-b1cb-4f90-908b-e939e8730924; host-name=\"xrtuk-13-06\"; pbd=bf08dedc-2564-df8c-3f61-b07654cf824a; scsi_id=3600a098038303973743f486833396d41; current=2; max=4",
+                "[20181016T09:55:52Z] host=2e257cd5-b1cb-4f90-908b-e939e8730924; host-name=\"xrtuk-13-06\"; root=true; current=2; max=4",
+                "[20181016T09:55:52Z] host=0d5b647c-d913-40e0-a94f-4b9c94dd41eb; host-name=\"xrtuk-12-05\"; pbd=bf08dedc-2564-df8c-3f61-b07654cf824a; scsi_id=3600a098038303973743f486833396d41; current=2; max=4"
+            };
+            var expected = new List<string> { "2e257cd5-b1cb-4f90-908b-e939e8730924", "0d5b647c-d913-40e0-a94f-4b9c94dd41eb" };
+            FindHostUuidsTestHelper(given, expected);
+        }
+
+        [Test]
+        public void TestFindHostUuidsTestGivenUnmatchedLinesShouldNotInterfere()
+        {
+            var given = new List<string>
+            {
+                "unmatched",
+                "[20181016T09:55:52Z] host=2e257cd5-b1cb-4f90-908b-e939e8730924; host-name=\"xrtuk-13-06\"; pbd=bf08dedc-2564-df8c-3f61-b07654cf824a; scsi_id=3600a098038303973743f486833396d41; current=2; max=4",
+                "unmatched",
+                "[20181016T09:55:52Z] host=2e257cd5-b1cb-4f90-908b-e939e8730924; host-name=\"xrtuk-13-06\"; root=true; current=2; max=4",
+                "unmatched",
+                "[20181016T09:55:52Z] host=0d5b647c-d913-40e0-a94f-4b9c94dd41eb; host-name=\"xrtuk-12-05\"; pbd=bf08dedc-2564-df8c-3f61-b07654cf824a; scsi_id=3600a098038303973743f486833396d41; current=2; max=4",
+                "unmatched"
+            };
+            var expected = new List<string> { "2e257cd5-b1cb-4f90-908b-e939e8730924", "0d5b647c-d913-40e0-a94f-4b9c94dd41eb" };
+            FindHostUuidsTestHelper(given, expected);
+        }
+
+        private static void FindHostUuidsTestHelper(IEnumerable<string> given, IEnumerable<string> expected)
+        {
+            var actual = MessageAlert.FindHostUuids(given);
+            Assert.IsNotNull(actual, "FindHostUuids should not return null.");
+            Assert.That(actual, Is.EquivalentTo(expected));
+        }
+    }
+}

XenAdminTests/XenAdminTests.csproj

@@ -73,6 +73,7 @@
     <Compile Include="HealthCheckTests\RequestUploadTaskTests.cs" />
     <Compile Include="UnitTests\BatchUpdatesTests\BatchUpdatesTests.cs" />
     <Compile Include="UnitTests\CPUFeaturesTest.cs" />
+    <Compile Include="UnitTests\AlertTests\MultipathAlertTest.cs" />
     <Compile Include="UnitTests\HealthCheckAnalysisProgressTest.cs" />
     <Compile Include="UnitTests\SubnetworkMaskValidatorTest.cs" />
     <Compile Include="UnitTests\ExceptionSerializationTest.cs" />