QueryEndpoint.SingleAsync also has option for passing single key value

Author: alex-kulakov

Orm/Xtensive.Orm.Tests/Storage/Prefetch/FetchByKeyWithCachingTest.cs

@@ -143,7 +143,7 @@ public void SingleByExistingIdTest()
     }
 
     [Test]
-    public async Task SingleByExistingIdAsyncTest()
+    public async Task SingleByExistingIdAsyncTest1()
     {
       await RunWithinSessionAsync(async (s) => {
         var existingId = (int) existingKeys[customerType][0].Value.GetValue(0, out var _);
@@ -164,6 +164,28 @@ await RunWithinSessionAsync(async (s) => {
       });
     }
 
+    [Test]
+    public async Task SingleByExistingIdAsyncTest2()
+    {
+      await RunWithinSessionAsync(async (s) => {
+        var existingId = (int) existingKeys[customerType][0].Value.GetValue(0, out var _);
+        var detector = new QueryExecutionDetector();
+        using (detector.Attach(s)) {
+          // Entity is not in cache yet
+          var existingEntity = await s.Query.SingleAsync<Customer>(existingId);
+        }
+        Assert.That(detector.DbCommandsDetected, Is.True);
+        detector.Reset();
+
+        using (detector.Attach(s)) {
+          // now it is in cache
+          var existingEntity = await s.Query.SingleAsync<Customer>(existingId);
+        }
+        Assert.That(detector.DbCommandsDetected, Is.False);
+        detector.Reset();
+      });
+    }
+
     [Test]
     public void SingleByInexistentIdTest()
     {
@@ -186,7 +208,7 @@ public void SingleByInexistentIdTest()
     }
 
     [Test]
-    public async Task SingleByInexistentIdAsyncTest()
+    public async Task SingleByInexistentIdAsyncTest1()
     {
       await RunWithinSessionAsync(async (s) => {
         var inexistentId = 9999;
@@ -207,6 +229,28 @@ await RunWithinSessionAsync(async (s) => {
       });
     }
 
+    [Test]
+    public async Task SingleByInexistentIdAsyncTest2()
+    {
+      await RunWithinSessionAsync(async (s) => {
+        var inexistentId = 9999;
+
+        var detector = new QueryExecutionDetector();
+        using (detector.Attach(s)) {
+          _ = Assert.ThrowsAsync<KeyNotFoundException>(async () => await s.Query.SingleAsync<Customer>(inexistentId));
+        }
+        Assert.That(detector.DbCommandsDetected, Is.True);
+        detector.Reset();
+
+        using (detector.Attach(s)) {
+          _ = Assert.ThrowsAsync<KeyNotFoundException>(async () => await s.Query.SingleAsync<Customer>(inexistentId));
+        }
+        Assert.That(detector.DbCommandsDetected, Is.False);
+        detector.Reset();
+        await Task.CompletedTask;
+      });
+    }
+
     [Test]
     public void SingleOrDefaultByExistingKeyTest()
     {

Orm/Xtensive.Orm/Orm/Query.cs

@@ -316,6 +316,23 @@ public static Task<T> SingleAsync<T>(object[] keyValues, CancellationToken token
       return Session.Demand().Query.SingleAsync<T>(keyValues, token);
     }
 
+    /// <summary>
+    /// Resolves (gets) the <see cref="Entity"/> by the specified <paramref name="keyValue"/>
+    /// in the current <see cref="Session"/>.
+    /// </summary>
+    /// <typeparam name="T">Type of the entity.</typeparam>
+    /// <param name="keyValue">Key value.</param>
+    /// <param name="token">The token to cancel this operation.</param>
+    /// <returns>
+    /// The <see cref="Entity"/> specified <paramref name="keyValue"/> identify.
+    /// </returns>
+    /// <exception cref="KeyNotFoundException">Entity with the specified key is not found.</exception>
+    public static Task<T> SingleAsync<T>(object keyValue, CancellationToken token)
+      where T : class, IEntity
+    {
+      return Session.Demand().Query.SingleAsync<T>(keyValue, token);
+    }
+
     /// <summary>
     /// Resolves (gets) the <see cref="Entity"/> by the specified <paramref name="key"/>
     /// in the current <see cref="Session"/>.

Orm/Xtensive.Orm/Orm/QueryEndpoint.cs

@@ -428,6 +428,23 @@ public async Task<T> SingleAsync<T>(object[] keyValues, CancellationToken token
       return (T) (object) (await SingleAsync(GetKeyByValues<T>(keyValues), token).ConfigureAwait(false));
     }
 
+    /// <summary>
+    /// Resolves (gets) the <see cref="Entity"/> by the specified <paramref name="keyValue"/>
+    /// in the current <see cref="session"/>.
+    /// </summary>
+    /// <typeparam name="T">Type of the entity.</typeparam>
+    /// <param name="keyValue">Key value.</param>
+    /// <param name="token">The token to cancel this operation.</param>
+    /// <returns>
+    /// The <see cref="Entity"/> specified <paramref name="keyValue"/> identify.
+    /// </returns>
+    /// <exception cref="KeyNotFoundException">Entity with the specified key is not found.</exception>
+    public async Task<T> SingleAsync<T>(object keyValue, CancellationToken token = default)
+      where T : class, IEntity
+    {
+      return (T) (object) (await SingleAsync(GetKeyByValue<T>(keyValue), token).ConfigureAwait(false));
+    }
+
     /// <summary>
     /// Resolves (gets) the <see cref="Entity"/> by the specified <paramref name="key"/>
     /// in the current <see cref="session"/>.