Merge 33ac43a4b8 into de4d415053

src/Discord.Net.Commands/CommandService.cs

@@ -1,3 +1,6 @@
+using Discord.Commands.Builders;
+using Discord.Logging;
+using Microsoft.Extensions.DependencyInjection;
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
@@ -350,8 +353,25 @@ namespace Discord.Commands
             => ExecuteAsync(context, context.Message.Content.Substring(argPos), services, multiMatchHandling);
         public async Task<IResult> ExecuteAsync(ICommandContext context, string input, IServiceProvider services, MultiMatchHandling multiMatchHandling = MultiMatchHandling.Exception)
         {
+            // Create service scope and command context so dependent services can consume the command context, with a scoped lifespan
             services = services ?? EmptyServiceProvider.Instance;
+            using (var serviceScope = services.CreateScope())
+            {
+                var scopedServices = serviceScope.ServiceProvider;
 
+                // If the context accessor is registered in the IoC container, set it
+                var contextAccessor = scopedServices.GetService<ICommandContextAccessor>();
+                if (contextAccessor != null)
+                {
+                    contextAccessor.CommandContext = context;
+                }
+                return await ExecuteAsyncInternal(context, input, scopedServices, multiMatchHandling);
+            }
+        }
+
+        internal async Task<IResult> ExecuteAsyncInternal(ICommandContext context, string input,
+            IServiceProvider services, MultiMatchHandling multiMatchHandling = MultiMatchHandling.Exception)
+        {
             var searchResult = Search(input);
             if (!searchResult.IsSuccess)
                 return searchResult;

src/Discord.Net.Core/Commands/CommandContextAccessor.cs

@@ -0,0 +1,16 @@
+using System.Threading;
+
+namespace Discord.Commands
+{
+    public class CommandContextAccessor : ICommandContextAccessor
+    {
+        private static AsyncLocal<ICommandContext> _commandContextCurrent = new AsyncLocal<ICommandContext>();
+
+        public ICommandContext CommandContext
+        {
+            get => _commandContextCurrent.Value;
+            set => _commandContextCurrent.Value = value;
+        }
+
+    }
+}

src/Discord.Net.Core/Commands/ICommandContextAccessor.cs

@@ -0,0 +1,7 @@
+namespace Discord.Commands
+{
+    public interface ICommandContextAccessor
+    {
+        ICommandContext CommandContext { get; set; }
+    }
+}