Instead of the Node process exiting instantly on file change, send a signal to .NET that it should restart. This is working towards the connection-draining feature.

Author: SteveSandersonMS

src/Microsoft.AspNetCore.NodeServices/Content/Node/entrypoint-http.js

@@ -184,7 +184,10 @@
 varext=path.extname(filename);
 if(extensions.indexOf(ext)>=0){
 console.log('Restarting due to file change: '+filename);
-process.exit(0);
+// Temporarily, the file-watching logic is in Node, so we signal it's time to restart by
+// sending the following message back to .NET. Soon the file-watching logic will move over
+// to the .NET side, and this whole file can be removed.
+console.log('[Microsoft.AspNetCore.NodeServices:Restart]');
 }
 });
 }

src/Microsoft.AspNetCore.NodeServices/Content/Node/entrypoint-socket.js

@@ -95,7 +95,10 @@
 varext=path.extname(filename);
 if(extensions.indexOf(ext)>=0){
 console.log('Restarting due to file change: '+filename);
-process.exit(0);
+// Temporarily, the file-watching logic is in Node, so we signal it's time to restart by
+// sending the following message back to .NET. Soon the file-watching logic will move over
+// to the .NET side, and this whole file can be removed.
+console.log('[Microsoft.AspNetCore.NodeServices:Restart]');
 }
 });
 }

src/Microsoft.AspNetCore.NodeServices/HostingModels/OutOfProcessNodeInstance.cs

@@ -18,6 +18,7 @@ namespace Microsoft.AspNetCore.NodeServices.HostingModels
 publicabstractclassOutOfProcessNodeInstance:INodeInstance
 {
 privateconststringConnectionEstablishedMessage="[Microsoft.AspNetCore.NodeServices:Listening]";
+privateconststringNeedsRestartMessage="[Microsoft.AspNetCore.NodeServices:Restart]";
 privatereadonlyTaskCompletionSource<object>_connectionIsReadySource=newTaskCompletionSource<object>();
 privatebool_disposed;
 privatereadonlyStringAsTempFile_entryPointScript;
@@ -128,6 +129,13 @@ private void ConnectToInputOutputStreams()
 _connectionIsReadySource.SetResult(null);
 initializationIsCompleted=true;
 }
+elseif(evt.Data==NeedsRestartMessage)
+{
+// Temporarily, the file-watching logic is in Node, so look out for the
+// signal that we need to restart. This can be removed once the file-watching
+// logic is moved over to the .NET side.
+Dispose();
+}
 elseif(evt.Data!=null)
 {
 OnOutputDataReceived(evt.Data);

src/Microsoft.AspNetCore.NodeServices/TypeScript/Util/AutoQuit.ts

@@ -8,7 +8,11 @@ export function autoQuitOnFileChange(rootDir: string, extensions: string[]){
 varext=path.extname(filename);
 if(extensions.indexOf(ext)>=0){
 console.log('Restarting due to file change: '+filename);
-process.exit(0);
+
+// Temporarily, the file-watching logic is in Node, so we signal it's time to restart by
+// sending the following message back to .NET. Soon the file-watching logic will move over
+// to the .NET side, and this whole file can be removed.
+console.log('[Microsoft.AspNetCore.NodeServices:Restart]');
 }
 });
 }