Fixed unit tests by adding a scope provider

Author: MarioAndron

src/WorkflowCore/Interface/IScopeProvider.cs

@@ -0,0 +1,17 @@
+using Microsoft.Extensions.DependencyInjection;
+
+namespace WorkflowCore.Interface
+{
+    /// <remarks>
+    /// The implemention of this interface will be responsible for
+    /// providing a new service scope for a DI container   
+    /// </remarks>
+    public interface IScopeProvider
+    {
+        /// <summary>
+        /// Create a new service scope
+        /// </summary>
+        /// <returns></returns>
+        IServiceScope CreateScope();
+    }
+}

src/WorkflowCore/ServiceCollectionExtensions.cs

@@ -46,6 +46,7 @@ public static IServiceCollection AddWorkflow(this IServiceCollection services, A
 
             services.AddSingleton<IWorkflowController, WorkflowController>();
             services.AddSingleton<IWorkflowHost, WorkflowHost>();
+            services.AddTransient<IScopeProvider, ScopeProvider>();
             services.AddTransient<IWorkflowExecutor, WorkflowExecutor>();
             services.AddTransient<ICancellationProcessor, CancellationProcessor>();
             services.AddTransient<IWorkflowBuilder, WorkflowBuilder>();

src/WorkflowCore/Services/ScopeProvider.cs

@@ -0,0 +1,25 @@
+using Microsoft.Extensions.DependencyInjection;
+using System;
+using WorkflowCore.Interface;
+
+namespace WorkflowCore.Services
+{
+    /// <summary>
+    /// A concrete implementation for the IScopeProvider interface
+    /// Largely to get around the problems of unit testing an extension method (CreateScope())
+    /// </summary>
+    public class ScopeProvider : IScopeProvider
+    {
+        private readonly IServiceProvider provider;
+
+        public ScopeProvider(IServiceProvider provider)
+        {
+            this.provider = provider;
+        }
+
+        public IServiceScope CreateScope()
+        {
+            return provider.CreateScope();
+        }
+    }
+}

src/WorkflowCore/Services/WorkflowExecutor.cs

@@ -14,6 +14,7 @@ public class WorkflowExecutor : IWorkflowExecutor
     {
         protected readonly IWorkflowRegistry _registry;
         protected readonly IServiceProvider _serviceProvider;
+        protected readonly IScopeProvider _scopeProvider;
         protected readonly IDateTimeProvider _datetimeProvider;
         protected readonly ILogger _logger;
         private readonly IExecutionResultProcessor _executionResultProcessor;
@@ -23,9 +24,10 @@ public class WorkflowExecutor : IWorkflowExecutor
 
         private IWorkflowHost Host => _serviceProvider.GetService<IWorkflowHost>();
 
-        public WorkflowExecutor(IWorkflowRegistry registry, IServiceProvider serviceProvider, IDateTimeProvider datetimeProvider, IExecutionResultProcessor executionResultProcessor, ILifeCycleEventPublisher publisher, ICancellationProcessor cancellationProcessor, WorkflowOptions options, ILoggerFactory loggerFactory)
+        public WorkflowExecutor(IWorkflowRegistry registry, IServiceProvider serviceProvider, IScopeProvider scopeProvider, IDateTimeProvider datetimeProvider, IExecutionResultProcessor executionResultProcessor, ILifeCycleEventPublisher publisher, ICancellationProcessor cancellationProcessor, WorkflowOptions options, ILoggerFactory loggerFactory)
         {
             _serviceProvider = serviceProvider;
+            _scopeProvider = scopeProvider;
             _registry = registry;
             _datetimeProvider = datetimeProvider;
             _publisher = publisher;
@@ -87,7 +89,7 @@ public async Task<WorkflowExecutorResult> Execute(WorkflowInstance workflow)
                             pointer.StartTime = _datetimeProvider.Now.ToUniversalTime();
                         }
 
-                        using (var scope = _serviceProvider.CreateScope())
+                        using (var scope = _scopeProvider.CreateScope())
                         {
                             _logger.LogDebug("Starting step {0} on workflow {1}", step.Name, workflow.Id);
 

test/WorkflowCore.UnitTests/Services/WorkflowExecutorFixture.cs

@@ -25,6 +25,7 @@ public class WorkflowExecutorFixture
         protected ILifeCycleEventPublisher EventHub;
         protected ICancellationProcessor CancellationProcessor;
         protected IServiceProvider ServiceProvider;
+        protected IScopeProvider ScopeProvider;
         protected IDateTimeProvider DateTimeProvider;
         protected WorkflowOptions Options;
 
@@ -33,6 +34,7 @@ public WorkflowExecutorFixture()
             Host = A.Fake<IWorkflowHost>();
             PersistenceProvider = A.Fake<IPersistenceProvider>();
             ServiceProvider = A.Fake<IServiceProvider>();
+            ScopeProvider = A.Fake<IScopeProvider>();
             Registry = A.Fake<IWorkflowRegistry>();
             ResultProcesser = A.Fake<IExecutionResultProcessor>();
             EventHub = A.Fake<ILifeCycleEventPublisher>();
@@ -41,13 +43,17 @@ public WorkflowExecutorFixture()
 
             Options = new WorkflowOptions(A.Fake<IServiceCollection>());
 
+            var scope = A.Fake<IServiceScope>();
+            A.CallTo(() => ScopeProvider.CreateScope()).Returns(scope);
+            A.CallTo(() => scope.ServiceProvider).Returns(ServiceProvider);
+
             A.CallTo(() => DateTimeProvider.Now).Returns(DateTime.Now);
 
             //config logging
             var loggerFactory = new LoggerFactory();
             loggerFactory.AddConsole(LogLevel.Debug);            
 
-            Subject = new WorkflowExecutor(Registry, ServiceProvider, DateTimeProvider, ResultProcesser, EventHub, CancellationProcessor, Options, loggerFactory);
+            Subject = new WorkflowExecutor(Registry, ServiceProvider, ScopeProvider, DateTimeProvider, ResultProcesser, EventHub, CancellationProcessor, Options, loggerFactory);
         }
 
         [Fact(DisplayName = "Should execute active step")]