Fix logging in commands

src/Discord.Net.Commands/Builders/ModuleClassBuilder.cs

@@ -5,6 +5,7 @@ using System.Reflection;
 using System.Threading.Tasks;
 
 using Discord.Commands.Builders;
+using Microsoft.Extensions.Logging;
 
 namespace Discord.Commands
 {
@@ -34,7 +35,7 @@ namespace Discord.Commands
                 }
                 else if (IsLoadableModule(typeInfo))
                 {
-                    await service._cmdLogger.WarningAsync($"Class {typeInfo.FullName} is not public and cannot be loaded. To suppress this message, mark the class with {nameof(DontAutoLoadAttribute)}.").ConfigureAwait(false);
+                    service._cmdLogger.LogWarning($"Class {typeInfo.FullName} is not public and cannot be loaded. To suppress this message, mark the class with {nameof(DontAutoLoadAttribute)}.");
                 }
             }
 
@@ -69,7 +70,7 @@ namespace Discord.Commands
                 result[typeInfo.AsType()] = module.Build(service, services);
             }
 
-            await service._cmdLogger.DebugAsync($"Successfully built {builtTypes.Count} modules.").ConfigureAwait(false);
+            service._cmdLogger.LogDebug($"Successfully built {builtTypes.Count} modules.");
 
             return result;
         }

src/Discord.Net.Commands/CommandService.cs

@@ -8,6 +8,7 @@ using System.Threading;
 using System.Threading.Tasks;
 using Discord.Commands.Builders;
 using Discord.Logging;
+using Microsoft.Extensions.Logging;
 
 namespace Discord.Commands
 {
@@ -29,12 +30,6 @@ namespace Discord.Commands
     /// </remarks>
     public class CommandService : IDisposable
     {
-        /// <summary>
-        ///     Occurs when a command-related information is received.
-        /// </summary>
-        public event Func<LogMessage, Task> Log { add { _logEvent.Add(value); } remove { _logEvent.Remove(value); } }
-        internal readonly AsyncEvent<Func<LogMessage, Task>> _logEvent = new AsyncEvent<Func<LogMessage, Task>>();
-
         /// <summary>
         ///     Occurs when a command is executed.
         /// </summary>
@@ -56,8 +51,8 @@ namespace Discord.Commands
         internal readonly bool _caseSensitive, _throwOnError, _ignoreExtraArgs;
         internal readonly char _separatorChar;
         internal readonly RunMode _defaultRunMode;
-        internal readonly Logger _cmdLogger;
-        internal readonly LogManager _logManager;
+        internal readonly ILogger _cmdLogger;
+        internal readonly ILoggerFactory _logManager;
         internal readonly IReadOnlyDictionary<char, char> _quotationMarkAliasMap;
 
         internal bool _isDisposed;
@@ -100,8 +95,14 @@ namespace Discord.Commands
             if (_defaultRunMode == RunMode.Default)
                 throw new InvalidOperationException("The default run mode cannot be set to Default.");
 
-            _logManager = new LogManager(config.LogLevel);
-            _logManager.Message += async msg => await _logEvent.InvokeAsync(msg).ConfigureAwait(false);
+            _logManager = config.LoggerFactory;
+
+            if (_logManager == null)
+            {
+                _logManager = new DefaultLoggerFactory();
+                _logManager.AddProvider(new DefaultLoggerProvider());
+            }
+            
             _cmdLogger = _logManager.CreateLogger("Command");
 
             _moduleLock = new SemaphoreSlim(1, 1);
@@ -349,7 +350,8 @@ namespace Discord.Commands
         public void AddTypeReader(Type type, TypeReader reader)
         {
             if (_defaultTypeReaders.ContainsKey(type))
-                _ = _cmdLogger.WarningAsync($"The default TypeReader for {type.FullName} was replaced by {reader.GetType().FullName}." +
+                _cmdLogger.LogWarning(
+                    $"The default TypeReader for {type.FullName} was replaced by {reader.GetType().FullName}." +
                     "To suppress this message, use AddTypeReader<T>(reader, true).");
             AddTypeReader(type, reader, true);
         }

src/Discord.Net.Commands/Info/CommandInfo.cs

@@ -1,4 +1,5 @@
 using Discord.Commands.Builders;
+using Microsoft.Extensions.Logging;
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
@@ -240,7 +241,7 @@ namespace Discord.Commands
 
         private async Task<IResult> ExecuteInternalAsync(ICommandContext context, object[] args, IServiceProvider services)
         {
-            await Module.Service._cmdLogger.DebugAsync($"Executing {GetLogText(context)}").ConfigureAwait(false);
+            Module.Service._cmdLogger.LogDebug($"Executing {GetLogText(context)}");
             try
             {
                 var task = _action(context, args, services, this);
@@ -274,7 +275,7 @@ namespace Discord.Commands
                     ex = ex.InnerException;
 
                 var wrappedEx = new CommandException(this, context, ex);
-                await Module.Service._cmdLogger.ErrorAsync(wrappedEx).ConfigureAwait(false);
+                Module.Service._cmdLogger.LogError(wrappedEx, wrappedEx.Message);
 
                 var result = ExecuteResult.FromError(ex);
                 await Module.Service._commandExecutedEvent.InvokeAsync(this, context, result).ConfigureAwait(false);
@@ -291,7 +292,7 @@ namespace Discord.Commands
             }
             finally
             {
-                await Module.Service._cmdLogger.VerboseAsync($"Executed {GetLogText(context)}").ConfigureAwait(false);
+                Module.Service._cmdLogger.LogTrace($"Executed {GetLogText(context)}");
             }
         }