NadekoBot/NadekoBot.Core/Services/ServiceProvider.cs
2017-10-13 06:14:54 +02:00

173 lines
6.0 KiB
C#

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.Reflection;
using System.Linq;
using System.Diagnostics;
using NLog;
#if GLOBAL_NADEKO
using NadekoBot.Common;
#endif
namespace NadekoBot.Core.Services
{
public interface INServiceProvider : IServiceProvider, IEnumerable<object>
{
T GetService<T>();
IEnumerable<Type> LoadFrom(Assembly assembly);
INServiceProvider AddManual<T>(T obj);
object Unload(Type t);
}
public class NServiceProvider : INServiceProvider
{
private readonly object _locker = new object();
private readonly Logger _log;
public readonly Dictionary<Type, object> _services = new Dictionary<Type, object>();
public IReadOnlyDictionary<Type, object> Services => _services;
public NServiceProvider()
{
_log = LogManager.GetCurrentClassLogger();
}
public T GetService<T>()
{
return (T)((IServiceProvider)(this)).GetService(typeof(T));
}
object IServiceProvider.GetService(Type serviceType)
{
_services.TryGetValue(serviceType, out var toReturn);
return toReturn;
}
public INServiceProvider AddManual<T>(T obj)
{
lock (_locker)
{
_services.TryAdd(typeof(T), obj);
}
return this;
}
public INServiceProvider UpdateManual<T>(T obj)
{
lock (_locker)
{
_services.Remove(typeof(T));
_services.TryAdd(typeof(T), obj);
}
return this;
}
public IEnumerable<Type> LoadFrom(Assembly assembly)
{
List<Type> addedTypes = new List<Type>();
Type[] allTypes;
try
{
allTypes = assembly.GetTypes();
}
catch (ReflectionTypeLoadException ex)
{
Console.WriteLine(ex.LoaderExceptions[0]);
return Enumerable.Empty<Type>();
}
var services = new Queue<Type>(allTypes
.Where(x => x.GetInterfaces().Contains(typeof(INService))
&& !x.GetTypeInfo().IsInterface && !x.GetTypeInfo().IsAbstract
#if GLOBAL_NADEKO
&& x.GetTypeInfo().GetCustomAttribute<NoPublicBot>() == null
#endif
)
.ToArray());
addedTypes.AddRange(services);
var interfaces = new HashSet<Type>(allTypes
.Where(x => x.GetInterfaces().Contains(typeof(INService))
&& x.GetTypeInfo().IsInterface));
var alreadyFailed = new Dictionary<Type, int>();
lock (_locker)
{
var sw = Stopwatch.StartNew();
var swInstance = new Stopwatch();
while (services.Count > 0)
{
var type = services.Dequeue(); //get a type i need to make an instance of
if (_services.TryGetValue(type, out _)) // if that type is already instantiated, skip
continue;
var ctor = type.GetConstructors()[0];
var argTypes = ctor
.GetParameters()
.Select(x => x.ParameterType)
.ToArray(); // get constructor argument types i need to pass in
var args = new List<object>(argTypes.Length);
foreach (var arg in argTypes) //get constructor arguments from the dictionary of already instantiated types
{
if (_services.TryGetValue(arg, out var argObj)) //if i got current one, add it to the list of instances and move on
args.Add(argObj);
else //if i failed getting it, add it to the end, and break
{
services.Enqueue(type);
if (alreadyFailed.ContainsKey(type))
{
alreadyFailed[type]++;
if (alreadyFailed[type] > 3)
_log.Warn(type.Name + " wasn't instantiated in the first 3 attempts. Missing " + arg.Name + " type");
}
else
alreadyFailed.Add(type, 1);
break;
}
}
if (args.Count != argTypes.Length)
continue;
swInstance.Restart();
var instance = ctor.Invoke(args.ToArray());
swInstance.Stop();
if (swInstance.Elapsed.TotalSeconds > 5)
_log.Info($"{type.Name} took {swInstance.Elapsed.TotalSeconds:F2}s to load.");
var interfaceType = interfaces.FirstOrDefault(x => instance.GetType().GetInterfaces().Contains(x));
if (interfaceType != null)
{
addedTypes.Add(interfaceType);
_services.TryAdd(interfaceType, instance);
}
_services.TryAdd(type, instance);
}
sw.Stop();
_log.Info($"All services loaded in {sw.Elapsed.TotalSeconds:F2}s");
}
return addedTypes;
}
public object Unload(Type t)
{
lock (_locker)
{
if (_services.TryGetValue(t, out var obj))
{
_services.Remove(t);
return obj;
}
}
return null;
}
IEnumerator IEnumerable.GetEnumerator() => _services.Values.GetEnumerator();
public IEnumerator<object> GetEnumerator() => _services.Values.GetEnumerator();
}
}