[client][managed][offline] purge should forget the deltatoken

Author: hasankhan

sdk/Managed/src/Microsoft.WindowsAzure.MobileServices/Table/Sync/MobileServiceSyncSettingsManager.cs

@@ -37,9 +37,15 @@ public virtual async Task<MobileServiceSystemProperties> GetSystemPropertiesAsyn
             return (MobileServiceSystemProperties)Int32.Parse(value);
         }
 
-        public virtual Task ResetDeltaTokenAsync(string tableName, string queryKey)
+        public virtual async Task ResetDeltaTokenAsync(string tableName, string queryKey)
         {
-            return this.store.DeleteAsync(MobileServiceLocalSystemTables.Config, GetDeltaTokenKey(tableName, queryKey));
+            string key = GetDeltaTokenKey(tableName, queryKey);
+
+            using (await this.cacheLock.Acquire(key, CancellationToken.None))
+            {
+                this.cache.Remove(key);
+                await this.store.DeleteAsync(MobileServiceLocalSystemTables.Config, key);
+            }
         }
 
         public async virtual Task<DateTimeOffset> GetDeltaTokenAsync(string tableName, string queryKey)

sdk/Managed/test/Microsoft.WindowsAzure.MobileServices.SQLiteStore.Test/UnitTests/SyncSettingsManagerTests.Integration.cs

@@ -12,6 +12,22 @@ public class SyncSettingsManagerTests : TestBase
         private const string TestQueryKey = "abc";
 
 
+        [AsyncTestMethod]
+        public async Task ResetDeltaTokenAsync_ResetsTheToken()
+        {
+            MobileServiceSyncSettingsManager settings = await GetSettingManager();
+
+            DateTimeOffset saved = new DateTime(2014, 7, 24, 3, 4, 5, DateTimeKind.Local);
+            await settings.SetDeltaTokenAsync(TestTable, TestQueryKey, saved);
+
+            DateTimeOffset read = await settings.GetDeltaTokenAsync(TestTable, TestQueryKey);
+            Assert.AreEqual(read, saved.ToUniversalTime());
+
+            await settings.ResetDeltaTokenAsync(TestTable, TestQueryKey);
+            read = await settings.GetDeltaTokenAsync(TestTable, TestQueryKey);
+            Assert.AreEqual(read, new DateTimeOffset(1970, 1, 1, 0, 0, 0, TimeSpan.Zero).ToUniversalTime());
+        }
+
         [AsyncTestMethod]
         public async Task GetDeltaTokenAsync_ReturnsMinValue_WhenTokenDoesNotExist()
         {

sdk/Managed/test/Microsoft.WindowsAzure.MobileServices.Test/UnitTests/Table/Sync/MobileServiceSyncTable.Generic.Test.cs

@@ -839,19 +839,47 @@ public async Task PurgeAsync_DoesNotTriggerPush_WhenThereIsNoOperationInTable()
         [AsyncTestMethod]
         public async Task PurgeAsync_ResetsDeltaToken_WhenQueryKeyIsSpecified()
         {
-            var store = new MobileServiceLocalStoreMock();
-            store.TableMap["stringId_test_table"] = new Dictionary<string, JObject>();
-            store.TableMap[MobileServiceLocalSystemTables.Config] = new Dictionary<string, JObject>();
-            store.TableMap[MobileServiceLocalSystemTables.Config]["stringId_test_table_latestNews_deltaToken"] = new JObject();
+            var hijack = new TestHttpHandler();
+            hijack.AddResponseContent(@"[{""id"":""abc"",""String"":""Hey"", ""__updatedAt"": ""2001-02-03T00:00:00.0000000+00:00""},
+                                         {""id"":""def"",""String"":""How"", ""__updatedAt"": ""2001-02-04T00:00:00.0000000+00:00""}]"); // first page
+            hijack.AddResponseContent("[]"); // last page of first pull
+            hijack.AddResponseContent("[]"); // second pull
 
-            IMobileServiceClient service = new MobileServiceClient("http://www.test.com", "secret...", new TestHttpHandler());
+            var store = new MobileServiceLocalStoreMock();
+            IMobileServiceClient service = new MobileServiceClient("http://www.test.com", "secret...", hijack);
             await service.SyncContext.InitializeAsync(store, new MobileServiceSyncHandler());
 
             IMobileServiceSyncTable<ToDoWithStringId> table = service.GetSyncTable<ToDoWithStringId>();
 
-            await table.PurgeAsync("latestNews", table.CreateQuery(), CancellationToken.None);
+            // ensure there is no delta token present already
+            Assert.IsFalse(store.TableMap.ContainsKey("stringId_test_table"));
+
+            // now pull down data
+            await table.PullAsync("items", table.CreateQuery());
 
-            Assert.IsFalse(store.TableMap[MobileServiceLocalSystemTables.Config].ContainsKey("stringId_test_table_latestNews_deltaToken"));
+            // ensure items were pulled down
+            Assert.AreEqual(store.TableMap["stringId_test_table"].Count, 2);
+            Assert.AreEqual(store.TableMap["stringId_test_table"]["abc"].Value<string>("String"), "Hey");
+            Assert.AreEqual(store.TableMap["stringId_test_table"]["def"].Value<string>("String"), "How");
+
+            // ensure delta token was updated
+            Assert.Equals(store.TableMap[MobileServiceLocalSystemTables.Config]["stringId_test_table_items_deltaToken"]["value"], "2001-02-04T00:00:00.0000000+00:00");
+
+            // now purge and forget the delta token
+            await table.PurgeAsync("items", null, CancellationToken.None);
+
+            // make sure data is purged
+            Assert.AreEqual(store.TableMap["stringId_test_table"].Count, 0);
+            // make sure delta token is removed
+            Assert.IsFalse(store.TableMap[MobileServiceLocalSystemTables.Config].ContainsKey("stringId_test_table_items_deltaToken"));
+
+            // pull again
+            await table.PullAsync("items", table.CreateQuery());
+
+            // verify request urls
+            AssertEx.MatchUris(hijack.Requests, "http://www.test.com/tables/stringId_test_table?$filter=(__updatedAt ge datetimeoffset'1970-01-01T00:00:00.0000000%2B00:00')&$orderby=__updatedAt&$skip=0&$top=50&__includeDeleted=true&__systemproperties=__updatedAt%2C__version%2C__deleted",
+                                                "http://www.test.com/tables/stringId_test_table?$filter=(__updatedAt ge datetimeoffset'2001-02-04T00:00:00.0000000%2B00:00')&$orderby=__updatedAt&$skip=0&$top=50&__includeDeleted=true&__systemproperties=__updatedAt%2C__version%2C__deleted",
+                                                "http://www.test.com/tables/stringId_test_table?$filter=(__updatedAt ge datetimeoffset'1970-01-01T00:00:00.0000000%2B00:00')&$orderby=__updatedAt&$skip=0&$top=50&__includeDeleted=true&__systemproperties=__updatedAt%2C__version%2C__deleted");
         }
 
         [AsyncTestMethod]