Add utilities for easier versioning usage

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - Introduce default version setting to DurableTaskClient and expose to orchestrator ([#393](https://github.com/microsoft/durabletask-dotnet/pull/393))
 - Add support for local credential types in DTS libraries ([#396](https://github.com/microsoft/durabletask-dotnet/pull/396))
+- Add utility for easier version comparison in orchestration context ([#394](https://github.com/microsoft/durabletask-dotnet/pull/394))
 
 ## v1.8.1
 

src/Abstractions/TaskOrchestrationContext.cs

@@ -403,6 +403,52 @@ public virtual ILogger CreateReplaySafeLogger(Type type)
     public virtual ILogger CreateReplaySafeLogger<T>()
         => new ReplaySafeLogger(this, this.LoggerFactory.CreateLogger<T>());
 
+    /// <summary>
+    /// Checks if the current orchestration version is greater than the specified version.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// If both versions are empty, this is considered false as neither can be greater.
+    /// </para>
+    /// <para>
+    /// An empty context version is less than a defined version in the parameter.
+    /// </para>
+    /// <para>
+    /// An empty parameter version is less than a defined version in the context.
+    /// </para>
+    /// </remarks>
+    /// <param name="version">The version to check against.</param>
+    /// <returns>True if the orchestration's version is greater than the provided version, false otherwise.</returns>
+    public virtual int CompareVersionTo(string version)
+    {
+        // Both versions are empty, treat as equal.
+        if (string.IsNullOrWhiteSpace(this.Version) && string.IsNullOrWhiteSpace(version))
+        {
+            return 0;
+        }
+
+        // An empty version in the context is always less than a defined version in the parameter.
+        if (string.IsNullOrWhiteSpace(this.Version))
+        {
+            return -1;
+        }
+
+        // An empty version in the parameter is always less than a defined version in the context.
+        if (string.IsNullOrWhiteSpace(version))
+        {
+            return 1;
+        }
+
+        // If both versions use the .NET Version class, return that comparison.
+        if (System.Version.TryParse(this.Version, out Version contextVersion) && System.Version.TryParse(version, out Version otherVersion))
+        {
+            return contextVersion.CompareTo(otherVersion);
+        }
+
+        // If we have gotten to here, we don't know the syntax of the versions we are comparing, use a string comparison as a final check.
+        return string.Compare(this.Version, version, StringComparison.OrdinalIgnoreCase);
+    }
+
     class ReplaySafeLogger : ILogger
     {
         readonly TaskOrchestrationContext context;

test/Abstractions.Tests/TaskOrchestrationContextVersionTests.cs

@@ -0,0 +1,106 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using Microsoft.Extensions.Logging;
+
+namespace Microsoft.DurableTask.Abstractions.Tests;
+public class TaskOrchestrationContextVersionTests
+{
+    [Theory]
+    [InlineData("1.1", "1.0", 1)]
+    [InlineData("1.0", "1.1", -1)]
+    [InlineData("1.0", "1.0", 0)]
+    [InlineData("", "1.0", -1)]
+    [InlineData("1.0", "", 1)]
+    [InlineData("", "", 0)]
+    [InlineData("1.0.1", "1.0.0", 1)]
+    [InlineData("1.0.0", "1.0.1", -1)]
+    [InlineData("alpha", "beta", -1)]
+    [InlineData("beta", "alpha", 1)]
+    [InlineData("alpha", "alpha", 0)]
+    public void OrchestrationContext_Version_ComparisonTests(string orchestrationVersion, string otherVersion, int comparisonResult)
+    {
+        TaskOrchestrationContext orchestrationContext = new TestTaskOrchestrationContext(orchestrationVersion);
+
+        if (comparisonResult > 0)
+        {
+            orchestrationContext.CompareVersionTo(otherVersion).Should().BeGreaterThan(0);
+        }
+        else if (comparisonResult < 0)
+        {
+            orchestrationContext.CompareVersionTo(otherVersion).Should().BeLessThan(0);
+        }
+        else
+        {
+            orchestrationContext.CompareVersionTo(otherVersion).Should().Be(0);
+        }
+    }
+
+    class TestTaskOrchestrationContext : TaskOrchestrationContext
+    {
+        internal readonly string version = string.Empty;
+
+        public TestTaskOrchestrationContext(string version)
+        {
+            this.version = version;
+        }
+        public override TaskName Name => throw new NotImplementedException();
+
+        public override string InstanceId => throw new NotImplementedException();
+
+        public override ParentOrchestrationInstance? Parent => throw new NotImplementedException();
+
+        public override DateTime CurrentUtcDateTime => throw new NotImplementedException();
+
+        public override bool IsReplaying => throw new NotImplementedException();
+
+        public override string Version => this.version;
+
+        protected override ILoggerFactory LoggerFactory => throw new NotImplementedException();
+
+        public override Task<TResult> CallActivityAsync<TResult>(TaskName name, object? input = null, TaskOptions? options = null)
+        {
+            throw new NotImplementedException();
+        }
+
+        public override Task<TResult> CallSubOrchestratorAsync<TResult>(TaskName orchestratorName, object? input = null, TaskOptions? options = null)
+        {
+            throw new NotImplementedException();
+        }
+
+        public override void ContinueAsNew(object? newInput = null, bool preserveUnprocessedEvents = true)
+        {
+            throw new NotImplementedException();
+        }
+
+        public override Task CreateTimer(DateTime fireAt, CancellationToken cancellationToken)
+        {
+            throw new NotImplementedException();
+        }
+
+        public override T? GetInput<T>() where T : default
+        {
+            throw new NotImplementedException();
+        }
+
+        public override Guid NewGuid()
+        {
+            throw new NotImplementedException();
+        }
+
+        public override void SendEvent(string instanceId, string eventName, object payload)
+        {
+            throw new NotImplementedException();
+        }
+
+        public override void SetCustomStatus(object? customStatus)
+        {
+            throw new NotImplementedException();
+        }
+
+        public override Task<T> WaitForExternalEvent<T>(string eventName, CancellationToken cancellationToken = default)
+        {
+            throw new NotImplementedException();
+        }
+    }
+}