Actor State TTL (#1164)

* Actor state TTL support

Signed-off-by: joshvanl <[email protected]>

examples/Actor/ActorClient/Program.cs

@@ -1,4 +1,4 @@
-// ------------------------------------------------------------------------
+// ------------------------------------------------------------------------
 // Copyright 2021 The Dapr Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -46,7 +46,7 @@ public static async Task Main(string[] args)
             var proxy = ActorProxy.Create<IDemoActor>(actorId, "DemoActor");
 
             Console.WriteLine("Making call using actor proxy to save data.");
-            await proxy.SaveData(data);
+            await proxy.SaveData(data, TimeSpan.FromMinutes(10));
             Console.WriteLine("Making call using actor proxy to get data.");
             var receivedData = await proxy.GetData();
             Console.WriteLine($"Received data is {receivedData}.");

examples/Actor/DemoActor/DemoActor.cs

@@ -1,4 +1,4 @@
-// ------------------------------------------------------------------------
+// ------------------------------------------------------------------------
 // Copyright 2021 The Dapr Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -41,12 +41,12 @@ public DemoActor(ActorHost host, BankService bank)
             this.bank = bank;
         }
 
-        public async Task SaveData(MyData data)
+        public async Task SaveData(MyData data, TimeSpan ttl)
         {
             Console.WriteLine($"This is Actor id {this.Id} with data {data}.");
 
             // Set State using StateManager, state is saved after the method execution.
-            await this.StateManager.SetStateAsync<MyData>(StateName, data);
+            await this.StateManager.SetStateAsync<MyData>(StateName, data, ttl);
         }
 
         public Task<MyData> GetData()
@@ -109,7 +109,7 @@ public async Task ReceiveReminderAsync(string reminderName, byte[] state, TimeSp
             // This method is invoked when an actor reminder is fired.
             var actorState = await this.StateManager.GetStateAsync<MyData>(StateName);
             actorState.PropertyB = $"Reminder triggered at '{DateTime.Now:yyyy-MM-ddTHH:mm:ss}'";
-            await this.StateManager.SetStateAsync<MyData>(StateName, actorState);
+            await this.StateManager.SetStateAsync<MyData>(StateName, actorState, ttl: TimeSpan.FromMinutes(5));
         }
 
         class TimerParams
@@ -173,7 +173,7 @@ public async Task TimerCallback(byte[] data)
         {
             var state = await this.StateManager.GetStateAsync<MyData>(StateName);
             state.PropertyA = $"Timer triggered at '{DateTime.Now:yyyyy-MM-ddTHH:mm:s}'";
-            await this.StateManager.SetStateAsync<MyData>(StateName, state);
+            await this.StateManager.SetStateAsync<MyData>(StateName, state, ttl: TimeSpan.FromMinutes(5));
             var timerParams = JsonSerializer.Deserialize<TimerParams>(data);
             Console.WriteLine("Timer parameter1: " + timerParams.IntParam);
             Console.WriteLine("Timer parameter2: " + timerParams.StringParam);

examples/Actor/IDemoActor/IDemoActor.cs

@@ -1,4 +1,4 @@
-// ------------------------------------------------------------------------
+// ------------------------------------------------------------------------
 // Copyright 2021 The Dapr Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -27,8 +27,9 @@ public interface IDemoActor : IActor
         /// Method to save data.
         /// </summary>
         /// <param name="data">DAta to save.</param>
+        /// <param name="ttl">TTL of state key.</param>
         /// <returns>A task that represents the asynchronous save operation.</returns>
-        Task SaveData(MyData data);
+        Task SaveData(MyData data, TimeSpan ttl);
 
         /// <summary>
         /// Method to get data.

src/Dapr.Actors/Communication/ActorStateResponse.cs

@@ -0,0 +1,50 @@
+// ------------------------------------------------------------------------
+// Copyright 2023 The Dapr Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//     http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+namespace Dapr.Actors.Communication
+{
+    using System;
+
+    /// <summary>
+    /// Represents a response from fetching an actor state key.
+    /// </summary>
+    public class ActorStateResponse<T>
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ActorStateResponse{T}"/> class.
+        /// </summary>
+        /// <param name="value">The response value.</param>
+        /// <param name="ttlExpireTime">The time to live expiration time.</param>
+        public ActorStateResponse(T value, DateTimeOffset? ttlExpireTime)
+        {
+            this.Value = value;
+            this.TTLExpireTime = ttlExpireTime;
+        }
+
+        /// <summary>
+        /// Gets the response value as a string.
+        /// </summary>
+        /// <value>
+        /// The response value as a string.
+        /// </value>
+        public T Value { get; }
+
+        /// <summary>
+        /// Gets the time to live expiration time.
+        /// </summary>
+        /// <value>
+        /// The time to live expiration time.
+        /// </value>
+        public DateTimeOffset? TTLExpireTime { get; }
+    }
+}

src/Dapr.Actors/Constants.cs

@@ -1,4 +1,4 @@
-// ------------------------------------------------------------------------
+// ------------------------------------------------------------------------
 // Copyright 2021 The Dapr Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -22,6 +22,7 @@ internal static class Constants
         public const string RequestHeaderName = "X-DaprRequestHeader";
         public const string ErrorResponseHeaderName = "X-DaprErrorResponseHeader";
         public const string ReentrancyRequestHeaderName = "Dapr-Reentrancy-Id";
+        public const string TTLResponseHeaderName = "Metadata.ttlExpireTime";
         public const string Dapr = "dapr";
         public const string Config = "config";
         public const string State = "state";

src/Dapr.Actors/DaprHttpInteractor.cs

@@ -57,7 +57,7 @@ public DaprHttpInteractor(
             this.httpClient.Timeout = requestTimeout ?? this.httpClient.Timeout;
         }
 
-        public async Task<string> GetStateAsync(string actorType, string actorId, string keyName, CancellationToken cancellationToken = default)
+        public async Task<ActorStateResponse<string>> GetStateAsync(string actorType, string actorId, string keyName, CancellationToken cancellationToken = default)
         {
             var relativeUrl = string.Format(CultureInfo.InvariantCulture, Constants.ActorStateKeyRelativeUrlFormat, actorType, actorId, keyName);
 
@@ -72,7 +72,18 @@ HttpRequestMessage RequestFunc()
 
             using var response = await this.SendAsync(RequestFunc, relativeUrl, cancellationToken);
             var stringResponse = await response.Content.ReadAsStringAsync();
-            return stringResponse;
+
+            DateTimeOffset? ttlExpireTime = null;
+            if (response.Headers.TryGetValues(Constants.TTLResponseHeaderName, out IEnumerable<string> headerValues))
+            {
+                var ttlExpireTimeString = headerValues.First();
+                if (!string.IsNullOrEmpty(ttlExpireTimeString))
+                {
+                    ttlExpireTime = DateTime.Parse(ttlExpireTimeString, CultureInfo.InvariantCulture);
+                }
+            }
+
+            return new ActorStateResponse<string>(stringResponse, ttlExpireTime);
         }
 
         public Task SaveStateTransactionallyAsync(string actorType, string actorId, string data, CancellationToken cancellationToken = default)

src/Dapr.Actors/IDaprInteractor.cs

@@ -1,4 +1,4 @@
-// ------------------------------------------------------------------------
+// ------------------------------------------------------------------------
 // Copyright 2021 The Dapr Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -52,7 +52,7 @@ internal interface IDaprInteractor
         /// <param name="keyName">Name of key to get value for.</param>
         /// <param name="cancellationToken">Cancels the operation.</param>
         /// <returns>A task that represents the asynchronous operation.</returns>
-        Task<string> GetStateAsync(string actorType, string actorId, string keyName, CancellationToken cancellationToken = default);
+        Task<ActorStateResponse<string>> GetStateAsync(string actorType, string actorId, string keyName, CancellationToken cancellationToken = default);
 
         /// <summary>
         /// Invokes Actor method.

src/Dapr.Actors/Runtime/ActorStateChange.cs

@@ -1,4 +1,4 @@
-// ------------------------------------------------------------------------
+// ------------------------------------------------------------------------
 // Copyright 2021 The Dapr Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -27,14 +27,16 @@ public sealed class ActorStateChange
         /// <param name="type">The type of value associated with given actor state name.</param>
         /// <param name="value">The value associated with given actor state name.</param>
         /// <param name="changeKind">The kind of state change for given actor state name.</param>
-        public ActorStateChange(string stateName, Type type, object value, StateChangeKind changeKind)
+        /// <param name="ttlExpireTime">The time to live for the state.</param>
+        public ActorStateChange(string stateName, Type type, object value, StateChangeKind changeKind, DateTimeOffset? ttlExpireTime)
         {
             ArgumentVerifier.ThrowIfNull(stateName, nameof(stateName));
 
             this.StateName = stateName;
             this.Type = type;
             this.Value = value;
             this.ChangeKind = changeKind;
+            this.TTLExpireTime = ttlExpireTime;
         }
 
         /// <summary>
@@ -68,5 +70,16 @@ public ActorStateChange(string stateName, Type type, object value, StateChangeKi
         /// The kind of state change for given actor state name.
         /// </value>
         public StateChangeKind ChangeKind { get; }
+
+        /// <summary>
+        /// Gets the time to live for the state.
+        /// </summary>
+        /// <value>
+        /// The time to live for the state.
+        /// </value>
+        /// <remarks>
+        /// If null, the state will not expire.
+        /// </remarks>
+        public DateTimeOffset? TTLExpireTime { get; }
     }
 }