removed timestamp from event id

Explore/Explore.csproj

@@ -33,6 +33,7 @@
     <DebugType>pdbonly</DebugType>
     <Optimize>true</Optimize>
     <DefineConstants>TRACE</DefineConstants>
+    <DocumentationFile>..\bin\AnyCPU\Release\Microsoft.Research.MultiWorldTesting.ExploreLibrary.XML</DocumentationFile>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="BaseExplorer.cs" />
@@ -55,12 +56,15 @@
     <Compile Include="MultiActionHelper.cs" />
     <Compile Include="TopSlotExplorer.cs" />
     <Compile Include="UniformRandomExploration.cs" />
-    <Compile Include="UniqueEventID.cs" />
   </ItemGroup>
   <ItemGroup>
+    <Reference Include="GitLink, Version=2.2.0.0, Culture=neutral, processorArchitecture=MSIL">
+      <HintPath>..\packages\gitlink.2.2.0\lib\net45\GitLink.exe</HintPath>
+      <Private>True</Private>
+    </Reference>
     <Reference Include="Newtonsoft.Json, Version=8.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\packages\Newtonsoft.Json.8.0.3\lib\net45\Newtonsoft.Json.dll</HintPath>
-      <HintPath>..\packages\Newtonsoft.Json.8.0.2\lib\net45\Newtonsoft.Json.dll</HintPath>
+      <Private>True</Private>
     </Reference>
     <Reference Include="System" />
   </ItemGroup>

Explore/Interface.cs

@@ -25,7 +25,7 @@ namespace Microsoft.Research.MultiWorldTesting.ExploreLibrary
         /// <param name="uniqueKey">A user-defined identifer for the decision.</param>
         /// <param name="modelId">Optional; The Id of the model used to make predictions/decisions, if any exists at decision time.</param>
         /// <param name="isExplore">Optional; Indicates whether the decision was generated purely from exploration (vs. exploitation).</param>
-        void Record(TContext context, TAction value, object explorerState, object mapperState, UniqueEventID uniqueKey); 
+        void Record(TContext context, TAction value, object explorerState, object mapperState, string uniqueKey); 
     }
 
     public interface IExplorer<TAction, TPolicyValue>

Explore/MwtExplorer.cs

@@ -111,6 +111,13 @@ namespace Microsoft.Research.MultiWorldTesting.ExploreLibrary
             }
         }
 
+        public TAction ChooseAction(string uniqueKey, TContext context, IContextMapper<TContext, TPolicyValue> defaultPolicy)
+        {
+            var policy = this.Policy;
+            var policyDecision = (policy ?? defaultPolicy).MapContext(context);
+            return ChooseActionInternal(uniqueKey, context, policyDecision);
+        }
+
 		/// <summary>
         /// Choose an action (or decision to take) given the exploration algorithm and context.
 		/// </summary>
@@ -119,46 +126,35 @@ namespace Microsoft.Research.MultiWorldTesting.ExploreLibrary
 		/// <param name="context">The context upon which a decision is made. See SimpleContext above for an example.</param>
         /// <param name="numActionsVariable">Optional; Number of actions available which may be variable across decisions.</param>
         /// <returns>An unsigned 32-bit integer representing the 1-based chosen action.</returns>
-        public TAction ChooseAction(UniqueEventID uniqueKey, TContext context, TAction initialAction)
+        public TAction ChooseAction(string uniqueKey, TContext context, TPolicyValue defaultPolicyDecision)
         {
             // Note: thread-safe atomic reference access
             var policy = this.Policy;
-            if (policy == null)
+            var policyDecision = (policy != null) ? policy.MapContext(context) : defaultPolicyDecision;
-            {
+            return ChooseActionInternal(uniqueKey, context, policyDecision);
-                // policy not ready & initial action provided
-                this.Log(uniqueKey, 
-                    context, 
-                    ExplorerDecision.Create(initialAction, new GenericExplorerState { Probability = 1 }, true));
-
-                return initialAction;
-            }
-
-            ulong saltedSeed = MurMurHash3.ComputeIdHash(uniqueKey.Key) + this.appId;
-            PRG random = new PRG(saltedSeed);
-
-            var policyDecision = policy.MapContext(context);
-            var explorerDecision = this.Explorer.MapContext(random, policyDecision.Value, this.numActionsProvider.GetNumberOfActions(context));
-            
-            this.Log(uniqueKey, context, explorerDecision, policyDecision);
-
-            return explorerDecision.Value;
         }
 
-        public TAction ChooseAction(UniqueEventID uniqueKey, TContext context)
+        public TAction ChooseAction(string uniqueKey, TContext context)
         {
-            ulong saltedSeed = MurMurHash3.ComputeIdHash(uniqueKey.Key) + this.appId;
+            ulong saltedSeed = MurMurHash3.ComputeIdHash(uniqueKey) + this.appId;
             PRG random = new PRG(saltedSeed);
 
             var policy = this.Policy;
             ExplorerDecision<TAction> explorerDecision;
             PolicyDecision<TPolicyValue> policyDecision = null;
 
+            int numActionsVariable = this.numActionsProvider.GetNumberOfActions(context);
+            if (numActionsVariable <= 0)
+            {
+                throw new Exception("Could not determine number of actions from the provided context.");
+            }
+
             if (policy == null)
-                explorerDecision = this.InitialExplorer.Explore(random, this.numActionsProvider.GetNumberOfActions(context));
+                explorerDecision = this.InitialExplorer.Explore(random, numActionsVariable);
             else
             {
                 policyDecision = policy.MapContext(context);
-                explorerDecision = this.Explorer.MapContext(random, policyDecision.Value, this.numActionsProvider.GetNumberOfActions(context));
+                explorerDecision = this.Explorer.MapContext(random, policyDecision.Value, numActionsVariable);
             }
 
             this.Log(uniqueKey, context, explorerDecision, policyDecision != null ? policyDecision.MapperState : null);
@@ -166,14 +162,6 @@ namespace Microsoft.Research.MultiWorldTesting.ExploreLibrary
             return explorerDecision.Value;
         }
 
-        private void Log(UniqueEventID uniqueKey, TContext context, ExplorerDecision<TAction> explorerDecision, object policyState = null)
-        {
-            if (explorerDecision.ShouldRecord)
-            {
-                this.recorder.Record(context, explorerDecision.Value, explorerDecision.ExplorerState, policyState, uniqueKey);
-            }
-        }
-
         /// <summary>
         /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
         /// </summary>
@@ -183,6 +171,32 @@ namespace Microsoft.Research.MultiWorldTesting.ExploreLibrary
             GC.SuppressFinalize(this);
         }
 
+        private TAction ChooseActionInternal(string uniqueKey, TContext context, PolicyDecision<TPolicyValue> policyDecision)
+        {
+            ulong saltedSeed = MurMurHash3.ComputeIdHash(uniqueKey) + this.appId;
+            PRG random = new PRG(saltedSeed);
+
+            int numActionsVariable = this.numActionsProvider.GetNumberOfActions(context);
+            if (numActionsVariable <= 0)
+            {
+                throw new Exception("Could not determine number of actions from the provided context.");
+            }
+
+            var explorerDecision = this.Explorer.MapContext(random, policyDecision.Value, numActionsVariable);
+
+            this.Log(uniqueKey, context, explorerDecision, policyDecision);
+
+            return explorerDecision.Value;
+        }
+
+        private void Log(string uniqueKey, TContext context, ExplorerDecision<TAction> explorerDecision, object policyState = null)
+        {
+            if (explorerDecision.ShouldRecord)
+            {
+                this.recorder.Record(context, explorerDecision.Value, explorerDecision.ExplorerState, policyState, uniqueKey);
+            }
+        }
+
         private void Dispose(bool disposing)
         {
             if (disposing)

Explore/Properties/AssemblyInfo.cs

@@ -26,5 +26,5 @@ using System.Runtime.InteropServices;
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.0.0.3")]
+[assembly: AssemblyVersion("1.0.0.4")]
-[assembly: AssemblyFileVersion("1.0.0.3")]
+[assembly: AssemblyFileVersion("1.0.0.4")]

Explore/StringRecorder.cs

@@ -25,11 +25,11 @@ namespace Microsoft.Research.MultiWorldTesting.ExploreLibrary.SingleAction
         /// <param name="action">Chosen by an exploration algorithm given context.</param>
         /// <param name="probability">The probability of the chosen action given context.</param>
         /// <param name="uniqueKey">A user-defined identifer for the decision.</param>
-        public void Record(TContext context, int value, object explorerState, object mapperState, UniqueEventID uniqueKey)
+        public void Record(TContext context, int value, object explorerState, object mapperState, string uniqueKey)
         {
             recordingBuilder.Append(value.ToString(CultureInfo.InvariantCulture));
             recordingBuilder.Append(' ');
-            recordingBuilder.Append(uniqueKey.Key);
+            recordingBuilder.Append(uniqueKey);
             recordingBuilder.Append(' ');
 
             recordingBuilder.Append(((GenericExplorerState)explorerState).Probability.ToString("0.00000", CultureInfo.InvariantCulture));

Explore/UniqueEventID.cs

@@ -1,27 +0,0 @@
-using System;
-
-namespace Microsoft.Research.MultiWorldTesting.ExploreLibrary
-{
-    /// <summary>
-    /// Represents a unique identifier for an event.
-    /// </summary>
-    public class UniqueEventID
-    {
-        /// <summary>
-        /// The key for the event.
-        /// </summary>
-        /// <remarks>
-        /// This key is used as a seed to the randomization, which
-        /// ensures consistent experience within same event, but
-        /// random across events.
-        /// </remarks>
-        public string Key { get; set; }
-
-        /// <summary>
-        /// The time stamp of the event which, together with the key,
-        /// uniquely identify an event. Events with same key
-        /// must have the same time stamp.
-        /// </summary>
-        public DateTime TimeStamp { get; set; }
-    }
-}

Explore/packages.config

@@ -1,4 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="Newtonsoft.Json" version="8.0.2" targetFramework="net45" />
+  <package id="gitlink" version="2.2.0" targetFramework="net45" />
+  <package id="Newtonsoft.Json" version="8.0.3" targetFramework="net45" />
 </packages>

Sample/ExploreOnlySample.cs

@@ -20,7 +20,7 @@ namespace cs_test
         /// </summary>
         class MyRecorder : IRecorder<MyContext, int>
         {
-            public void Record(MyContext context, int value, object explorerState, object mapperState, UniqueEventID uniqueKey)
+            public void Record(MyContext context, int value, object explorerState, object mapperState, string uniqueKey)
             {
                 // Stores the tuple internally in a vector that could be used later for other purposes.
                 interactions.Add(new Interaction<MyContext>()
@@ -28,7 +28,7 @@ namespace cs_test
                     Context = context,
                     Action = (uint)value,
                     Probability = ((GenericExplorerState)explorerState).Probability,
-                    UniqueKey = uniqueKey.Key
+                    UniqueKey = uniqueKey
                 });
             }
 
@@ -134,7 +134,7 @@ namespace cs_test
                 // Performs exploration by passing an instance of the Epsilon-Greedy exploration algorithm into MwtExplorer
                 // using a sample string to uniquely identify this event
                 string uniqueKey = "eventid";
-                int action = mwtt.ChooseAction(new UniqueEventID { Key = uniqueKey, TimeStamp = DateTime.UtcNow }, context);
+                int action = mwtt.ChooseAction(uniqueKey, context);
 
                 Console.WriteLine(recorder.GetRecording());
 
@@ -151,7 +151,7 @@ namespace cs_test
                 //MwtExplorer<MyContext> mwtt = new MwtExplorer<MyContext>("mwt", recorder);
                 var mwtt = MwtExplorer.Create("mwt", numActions, recorder, new TauFirstExplorer(tau), new MyPolicy());
 
-                int action = mwtt.ChooseAction(new UniqueEventID { Key = "key", TimeStamp = DateTime.UtcNow }, new MyContext());
+                int action = mwtt.ChooseAction("key", new MyContext());
                 Console.WriteLine(String.Join(",", recorder.GetAllInteractions().Select(it => it.Action)));
                 return;
             }

Test/BlackBox/Program.cs

@@ -315,7 +315,7 @@ namespace BlackBoxTests
 
                     for (int i = 0; i < experimentalUnitIdList.Length; i++)
                     {
-                        mwt.ChooseAction(new UniqueEventID { Key = experimentalUnitIdList[i] }, contextList[i]);
+                        mwt.ChooseAction(experimentalUnitIdList[i], contextList[i]);
                     }
 
                     File.AppendAllText(outputFile, recorder.GetRecording());
@@ -358,7 +358,7 @@ namespace BlackBoxTests
                     for (int i = 0; i < experimentalUnitIdList.Length; i++)
                     {
                         int numActionsVariable = isVariableActionContext ? ((IVariableActionContext)contextList[i]).GetNumberOfActions() : int.MaxValue;
-                        mwt.ChooseAction(new UniqueEventID { Key = experimentalUnitIdList[i] }, contextList[i]);
+                        mwt.ChooseAction(experimentalUnitIdList[i], contextList[i]);
                     }
 
                     File.AppendAllText(outputFile, recorder.GetRecording());
@@ -401,7 +401,7 @@ namespace BlackBoxTests
                     for (int i = 0; i < experimentalUnitIdList.Length; i++)
                     {
                         int numActionsVariable = isVariableActionContext ? ((IVariableActionContext)contextList[i]).GetNumberOfActions() : int.MaxValue;
-                        mwt.ChooseAction(new UniqueEventID { Key = experimentalUnitIdList[i] }, contextList[i]);
+                        mwt.ChooseAction(experimentalUnitIdList[i], contextList[i]);
                     }
 
                     File.AppendAllText(outputFile, recorder.GetRecording());
@@ -422,7 +422,7 @@ namespace BlackBoxTests
                     for (int i = 0; i < experimentalUnitIdList.Length; i++)
                     {
                         int numActionsVariable = isVariableActionContext ? ((IVariableActionContext)contextList[i]).GetNumberOfActions() : int.MaxValue;
-                        mwt.ChooseAction(new UniqueEventID { Key = experimentalUnitIdList[i] }, contextList[i]);
+                        mwt.ChooseAction(experimentalUnitIdList[i], contextList[i]);
                     }
 
                     File.AppendAllText(outputFile, recorder.GetRecording());
@@ -464,7 +464,7 @@ namespace BlackBoxTests
                     for (int i = 0; i < experimentalUnitIdList.Length; i++)
                     {
                         int numActionsVariable = isVariableActionContext ? ((IVariableActionContext)contextList[i]).GetNumberOfActions() : int.MaxValue;
-                        mwt.ChooseAction(new UniqueEventID { Key = experimentalUnitIdList[i] }, contextList[i]);
+                        mwt.ChooseAction(experimentalUnitIdList[i], contextList[i]);
                     }
 
                     File.AppendAllText(outputFile, recorder.GetRecording());
@@ -486,7 +486,7 @@ namespace BlackBoxTests
                     for (int i = 0; i < experimentalUnitIdList.Length; i++)
                     {
                         int numActionsVariable = isVariableActionContext ? ((IVariableActionContext)contextList[i]).GetNumberOfActions() : int.MaxValue;
-                        mwt.ChooseAction(new UniqueEventID { Key = experimentalUnitIdList[i] }, contextList[i]);
+                        mwt.ChooseAction(experimentalUnitIdList[i], contextList[i]);
                     }
 
                     File.AppendAllText(outputFile, recorder.GetRecording());

Test/Unit/MWTExploreTests.cs

@@ -44,7 +44,7 @@ namespace ExploreTests.SingleAction
             where TContext : RegularTestContext
         {
             string uniqueKey = "ManagedTestId";
-            var uniqueId = new UniqueEventID { Key = uniqueKey, TimeStamp = DateTime.UtcNow };
+            var uniqueId = uniqueKey;
             TestRecorder<TContext> recorder = new TestRecorder<TContext>();
             //MwtExplorer<TContext> mwtt = new MwtExplorer<TContext>("mwt", recorder);
             var mwtt = MwtExplorer.Create("mwt", numActions, recorder, explorer, policy);
@@ -98,7 +98,7 @@ namespace ExploreTests.SingleAction
             where TContext : RegularTestContext
         {
             string uniqueKey = "ManagedTestId";
-            var uniqueId = new UniqueEventID { Key = uniqueKey, TimeStamp = DateTime.UtcNow };
+            var uniqueId = uniqueKey;
 
             var recorder = new TestRecorder<TContext>();
 
@@ -240,7 +240,7 @@ namespace ExploreTests.SingleAction
             Random rand = new Random();
             for (uint i = 0; i < contexts.Length; i++)
             {
-                var uniqueId = new UniqueEventID { Key = rand.NextDouble().ToString(), TimeStamp = DateTime.UtcNow };
+                var uniqueId = rand.NextDouble().ToString();
                 int chosenAction = mwtt.ChooseAction(uniqueId, contexts[i]);
                 actions[chosenAction - 1]++; // action id is one-based
             }
@@ -273,9 +273,9 @@ namespace ExploreTests.SingleAction
             var mwtt = MwtExplorer.Create("mwt", numActions, recorder, explorer, scorer);
 
             Random rand = new Random();
-            mwtt.ChooseAction(new UniqueEventID { Key = rand.NextDouble().ToString() }, new RegularTestContext() { Id = 100 });
+            mwtt.ChooseAction(rand.NextDouble().ToString(), new RegularTestContext() { Id = 100 });
-            mwtt.ChooseAction(new UniqueEventID { Key = rand.NextDouble().ToString() }, new RegularTestContext() { Id = 101 });
+            mwtt.ChooseAction(rand.NextDouble().ToString(), new RegularTestContext() { Id = 101 });
-            mwtt.ChooseAction(new UniqueEventID { Key = rand.NextDouble().ToString() }, new RegularTestContext() { Id = 102 });
+            mwtt.ChooseAction(rand.NextDouble().ToString(), new RegularTestContext() { Id = 102 });
 
             var interactions = recorder.GetAllInteractions();
             
@@ -305,7 +305,7 @@ namespace ExploreTests.SingleAction
             explorer.EnableExplore(false);
             for (int i = 0; i < 1000; i++)
             {
-                int chosenAction = mwtt.ChooseAction(new UniqueEventID { Key = rand.NextDouble().ToString() }, new RegularTestContext() { Id = (int)i });
+                int chosenAction = mwtt.ChooseAction(rand.NextDouble().ToString(), new RegularTestContext() { Id = (int)i });
                 Assert.AreEqual(highestScoreAction, chosenAction);
             }
         }
@@ -339,7 +339,7 @@ namespace ExploreTests.SingleAction
             //var mwtt = new MwtExplorer<TContext>("mwt", recorder);
             var mwtt = MwtExplorer.Create("mwt", numActions, recorder, explorer, scorer);
 
-            int chosenAction = mwtt.ChooseAction(new UniqueEventID { Key = uniqueKey }, testContext);
+            int chosenAction = mwtt.ChooseAction(uniqueKey, testContext);
 
             var interactions = recorder.GetAllInteractions();
             Assert.AreEqual(1, interactions.Count);
@@ -367,14 +367,14 @@ namespace ExploreTests.SingleAction
 
     class TestRecorder<Ctx> : IRecorder<Ctx, int>
     {
-        public void Record(Ctx context, int value, object explorerState, object mapperState, UniqueEventID uniqueKey)
+        public void Record(Ctx context, int value, object explorerState, object mapperState, string uniqueKey)
         {
             interactions.Add(new TestInteraction<Ctx>()
             { 
                 Context = context,
                 Action = (uint)value,
                 Probability = ((GenericExplorerState)explorerState).Probability,
-                UniqueKey = uniqueKey.Key
+                UniqueKey = uniqueKey
             });
         }