fix bugs around retrieving cache items, note that sliding expiration doesn't work properly as of now

README.md

@@ -3,6 +3,8 @@ Use azure table storage for AspNet core 1.0 Distributed Cache.
 
 Azure Table Storage is a very cheap, [super fast](https://www.troyhunt.com/working-with-154-million-records-on/) key value store, and its much cheaper than the redis cluster in azure. This is not a true replacement for redis, and redis should be used if people have money, but this is designed to get people a very cheap cache in azure. Currently this doesn't actually support the dotnet core runtime, and won't until the Azure Storage client is updated to support core.
 
+**warning** As of right now sliding expiration doesn't work. This is at the top of the list to get working
+
 ## How to use
 
 `install-package AzureTableStorageCache`
@@ -22,7 +24,9 @@ In your startup.cs
 
 ```
 
-Then in a controller just ask for an IDistributedCache in the constructor. Since this implements Microsoft's IDistributed cache, it could be easily swapped out for redis or another Distributed cache
+Then in a controller just ask for an IDistributedCache in the constructor. Since this implements Microsoft's IDistributed cache, it could be easily swapped out for redis or another Distributed cache.
+
+
 
 ```csharp
 

src/AzureTableStorageCache/AzureTableStorageCacheHandler.cs

@@ -34,7 +34,6 @@ namespace AzureTableStorageCache
             }
             this.tableName = tableName;
             this.partitionKey = partitionKey;
-            Connect();
         }
 
         public AzureTableStorageCacheHandler(string accountName, string accountKey, string tableName, string partitionKey)
@@ -51,6 +50,7 @@ namespace AzureTableStorageCache
 
             this.accountName = accountName;
             this.accountKey = accountKey;
+            Connect();
         }
 
         private readonly string tableName;
@@ -64,6 +64,7 @@ namespace AzureTableStorageCache
             }
 
             this.connectionString = connectionString;
+            Connect();
         }
 
         public void Connect()
@@ -99,10 +100,13 @@ namespace AzureTableStorageCache
 
         public async Task<byte[]> GetAsync(string key)
         {
-            await RefreshAsync(key);
+            var cachedItem = await RetrieveAsync(key);
-            var op = TableOperation.Retrieve(partitionKey, key);
+            if (cachedItem != null && cachedItem.Data != null && ShouldDelete(cachedItem))
-            var result = await azuretable.ExecuteAsync(op);
+            {
-            return (result?.Result as CachedItem)?.Data;
+                await RemoveAsync(key);
+                return null;
+            }
+            return cachedItem?.Data;
         }
 
         public void Refresh(string key)
@@ -112,9 +116,7 @@ namespace AzureTableStorageCache
 
         public async Task RefreshAsync(string key)
         {
-            var op = TableOperation.Retrieve(partitionKey, key);
+            var data = await RetrieveAsync(key);
-            var result = await azuretable.ExecuteAsync(op);
-            var data = result?.Result as CachedItem;
             if (data != null)
             {
                 if (ShouldDelete(data))
@@ -125,6 +127,14 @@ namespace AzureTableStorageCache
             }
         }
 
+        private async Task<CachedItem> RetrieveAsync(string key)
+        {
+            var op = TableOperation.Retrieve<CachedItem>(partitionKey, key);
+            var result = await azuretable.ExecuteAsync(op);
+            var data = result?.Result as CachedItem;
+            return data;
+        }
+
         private bool ShouldDelete(CachedItem data)
         {
             var currentTime = DateTimeOffset.UtcNow;
@@ -176,6 +186,14 @@ namespace AzureTableStorageCache
                 absoluteExpiration = options.AbsoluteExpiration;
             }
             var item = new CachedItem(partitionKey, key, value) { LastAccessTime = currentTime };
+            if (absoluteExpiration.HasValue)
+            {
+                item.AbsolutExperiation = absoluteExpiration;
+            }
+            if (options.SlidingExpiration.HasValue)
+            {
+                item.SlidingExperiation = options.SlidingExpiration;
+            }
             var op = TableOperation.InsertOrReplace(item);
             return this.azuretable.ExecuteAsync(op);
         }

src/AzureTableStorageCache/project.json

@@ -1,5 +1,5 @@
 {
-  "version": "1.1.0-*",
+  "version": "1.2.0-*",
 
   "dependencies": {
     "NETStandard.Library": "1.5.0-rc2-24027",

src/AzureTableStorageCacheSample/Controllers/HomeController.cs

@@ -19,12 +19,16 @@ namespace AzureTableStorageCacheSample.Controllers
 
         public async Task<IActionResult> Index()
         {
-            var data = await cacheMechanism.GetAsync("awesomeRecord");
+            await cacheMechanism.SetAsync("awesomeRecord2", Encoding.UTF32.GetBytes("records are awesome"), new DistributedCacheEntryOptions() { SlidingExpiration = new TimeSpan(0, 5, 0) });
+            var data = await cacheMechanism.GetAsync("awesomeRecord2");
             var result = string.Empty;
             if (data != null)
             {
                 result = Encoding.UTF32.GetString(data);
             }
+            else
+            {
+            }
             return View(result);
         }
 

src/AzureTableStorageCacheSample/Startup.cs

@@ -29,7 +29,7 @@ namespace AzureTableStorageCacheSample
         // This method gets called by the runtime. Use this method to add services to the container.
         public void ConfigureServices(IServiceCollection services)
         {
-            services.AddAzureTableStorageCache("!!!CONNECTIONSTRINGHERE!!!", "tablename", "partitionKey");
+            services.AddAzureTableStorageCache("DefaultEndpointsProtocol=https;AccountName=tparnell;AccountKey=cEHdbvM6bljcIYOaODs16vRokLDvxujEn+JR/8MWgYE/9g4mw95n/jusTAdvhc/JrySfZGwaq/WIg9Bi/TeoOw==", "yodawg", "cachingforlyfe");
             // Add framework services.
             services.AddMvc();
         }