Refactor BootService

src/SkyWalking.Abstractions/Boot/IBootService.cs

@@ -17,11 +17,13 @@
  */
 
 using System;
+using System.Threading;
+using System.Threading.Tasks;
 
 namespace SkyWalking.Boot
 {
-    public interface IBootService: IDisposable
+    public interface IBootService : IDisposable
     {
-        void Init();
+        Task Initialize(CancellationToken token);
     }
 }
\ No newline at end of file

src/SkyWalking.Abstractions/Config/CollectorConfig.cs

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+namespace SkyWalking.Config
+{
+    public class CollectorConfig
+    {
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Boot/ServiceManager.cs

@@ -20,6 +20,8 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
 
 namespace SkyWalking.Boot
 {
@@ -30,6 +32,7 @@ namespace SkyWalking.Boot
         public static ServiceManager Instance => _instance;
         
         private readonly Dictionary<Type, object> _services = new Dictionary<Type, object>();
+        private readonly CancellationTokenSource _tokenSource = new CancellationTokenSource();
 
         private ServiceManager()
         {
@@ -52,16 +55,14 @@ namespace SkyWalking.Boot
             return (T) GetService(typeof(T));
         }
 
-        
-        [MethodImpl(MethodImplOptions.Synchronized)]
-        public void Init()
+        public async Task Initialize()
         {
             var types = FindServiceTypes();
             foreach (var type in types)
             {
                 if (Activator.CreateInstance(type) is IBootService service)
                 {
-                    service.Init();
+                    await service.Initialize(_tokenSource.Token);
                     _services.Add(type, service);
                 }
             }
@@ -70,11 +71,13 @@ namespace SkyWalking.Boot
         [MethodImpl(MethodImplOptions.Synchronized)]
         public void Dispose()
         {
+            _tokenSource.Cancel();
             foreach (var item in _services.Values)
             {
                 var service = item as IBootService;
                 service?.Dispose();
             }
+            _tokenSource.Dispose();
         }
     }
 }
\ No newline at end of file

src/SkyWalking.Core/Boot/TimerService.cs

+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace SkyWalking.Boot
+{
+    public abstract class TimerService : IBootService
+    {
+        protected abstract TimeSpan Interval { get; }
+        private Task _task;
+
+        public virtual void Dispose()
+        {
+        }
+
+        public async Task Initialize(CancellationToken token)
+        {
+            await Initializing(token);
+            _task = Task.Factory.StartNew(async () =>
+                {
+                    while (true)
+                    {
+                        await Execute(token);
+                        await Task.Delay(Interval, token);
+                    }  
+                },
+                token, TaskCreationOptions.LongRunning, TaskScheduler.Default);
+        }
+
+        protected virtual Task Initializing(CancellationToken token)
+        {
+            return Task.CompletedTask;
+        }
+
+        protected abstract Task Execute(CancellationToken token);
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Context/ContextManager.cs

@@ -18,6 +18,7 @@
 
 using System;
 using System.Threading;
+using System.Threading.Tasks;
 using SkyWalking.Boot;
 using SkyWalking.Config;
 using SkyWalking.Context.Trace;
@@ -178,10 +179,11 @@ namespace SkyWalking.Context
         {
         }
 
-        public void Init()
+        public Task Initialize(CancellationToken token)
         {
             TracingContext.ListenerManager.Add(this);
             IgnoredTracerContext.ListenerManager.Add(this);
+            return Task.CompletedTask;
         }
 
         public void AfterFinish(ITracerContext tracerContext)

src/SkyWalking.Core/Sampling/SamplingService.cs

@@ -16,6 +16,9 @@
  *
  */
 
+using System.Threading;
+using System.Threading.Tasks;
+
 namespace SkyWalking.Sampling
 {
     public class SamplingService : ISampler
@@ -32,12 +35,11 @@ namespace SkyWalking.Sampling
 
         public void Dispose()
         {
-            throw new System.NotImplementedException();
         }
 
-        public void Init()
+        public Task Initialize(CancellationToken token)
         {
-            throw new System.NotImplementedException();
+            return Task.CompletedTask;
         }
     }
 }
\ No newline at end of file

src/SkyWalking.Core/SkyWalking.Core.csproj

@@ -14,4 +14,7 @@
   <ItemGroup>
     <ProjectReference Include="..\SkyWalking.Abstractions\SkyWalking.Abstractions.csproj" />
   </ItemGroup>
+  <ItemGroup>
+    <Folder Include="Remote" />
+  </ItemGroup>
 </Project>
\ No newline at end of file