memcache CAS locking for casrepositoryflush implemented

Author: lanesCSO

rls/packages/API.Library.6.1.25.nupkg

@@ -12,12 +12,12 @@
     <PackageId>API.Library</PackageId>
     <Product>API Library</Product>
     <Copyright>Central Statistics Office, Ireland</Copyright>
-    <Version>6.1.24</Version>
+    <Version>6.1.25</Version>
     <Authors>Central Statistics Office, Ireland</Authors>
     <SignAssembly>False</SignAssembly>
     <RepositoryUrl>https://github.com/CSOIreland/Server-API-Library</RepositoryUrl>
     <PackageReleaseNotes>
-      [BUG FIX] Dispose of database connection if it cant't be opened
+      [ENHANCEMENT] memcache CAS locking for casrepositoryflush implemented
     </PackageReleaseNotes>
     <RestorePackagesWithLockFile>true</RestorePackagesWithLockFile>
     <RestoreLockedMode>true</RestoreLockedMode>
@@ -34,6 +34,8 @@
 	  <None Remove="Entities\ADO.cs~RF5780ef96.TMP" />
 	  <None Remove="Entities\API.Common.cs~RF1e6b9c0d.TMP" />
 	  <None Remove="Entities\MemCacheD.cs~RFcba3198.TMP" />
+	  <None Remove="Entities\MemCacheD.cs~RFf6fcfeae.TMP" />
+	  <None Remove="Entities\MemCacheD.cs~RFf747b93c.TMP" />
 	  <None Remove="log4net.config" />
 	</ItemGroup>
 

src/API.Library/API.Library.csproj

@@ -70,6 +70,39 @@ private static bool IsEnabled()
             }
         }
 
+
+        /// <summary>
+        /// Check if MemCacheD cas is locked
+        /// </summary>
+        /// <returns></returns>
+        private bool IsCasLocked(string repository)
+        {
+            if (string.IsNullOrEmpty(repository))
+            {
+                return false;
+            }
+            else
+            {
+                // Force to Case Insensitive
+                repository = repository.ToUpper();
+            }
+
+
+            Log.Instance.Info("IsCasLocked repository is " + repository);
+
+            MemCachedD_Value casLock = Get_BSO<dynamic>("API", "MemCacheD", "casManagement",  repository + "-Lock");
+
+
+            if (casLock.hasData)
+            {
+                return casLock.data.Value;
+            }
+            else
+            {
+                return false;
+            }
+        }
+
         /// <summary>
         /// Generate the Key for ADO
         /// </summary>
@@ -427,6 +460,11 @@ private bool Store(string key, MemCachedD_Value value, TimeSpan validFor, string
                 return false;
             }
 
+            if (IsCasLocked(repository))
+            {
+                return false;
+            }
+
             Stopwatch sw = Stopwatch.StartNew();
             int? cacheTraceCompressLength = null;
             DateTime traceStart = DateTime.Now;
@@ -636,9 +674,6 @@ private void CasRepositoryStore(string key, string repository)
             // Initiate Keys
             List<string> keys = new List<string>();
 
-
-
-
             try
             {
                 // Initiate loop
@@ -721,13 +756,15 @@ private void CasRepositoryStore(string key, string repository)
         /// <param name="repository"></param>
         public bool CasRepositoryFlush(string repository)
         {
+
             Exception ex = null;
             // Check if it's enabled first
             if (!IsEnabled())
             {
                 return false;
             }
 
+
             if (string.IsNullOrEmpty(repository))
             {
                 return false;
@@ -738,6 +775,23 @@ public bool CasRepositoryFlush(string repository)
                 repository = repository.ToUpper();
             }
 
+            /*** cas lock management **/
+            if (IsCasLocked(repository))
+            {
+                return false;
+            }
+
+            ApiServicesHelper.CacheD.Store_BSO<dynamic>("API", "MemCacheD", "casManagement", repository + "-Lock", true, DateTime.Today.AddMinutes(2), "METACAS");
+           
+            MemCachedD_Value casLock = Get_BSO<dynamic>("API", "MemCacheD", "casManagement", repository + "-Lock");
+
+            //lock failed to set
+            if (!casLock.hasData)
+            {
+                return false;
+            }
+            /*** end cas lock management **/
+
             Stopwatch sw = Stopwatch.StartNew();
             DateTime traceStart = DateTime.Now;
             bool successTraceFlag = true;
@@ -835,6 +889,9 @@ public bool CasRepositoryFlush(string repository)
             }
             finally
             {
+                //unlock the cas
+                Remove_BSO<dynamic>("API", "MemCacheD", "casManagement", repository + "-Lock");
+
                 sw.Stop();
                 var duration = Utility.StopWatchToSeconds(sw);