Reworked GrpcEnvironment initialization and shutdown to allow running all tests at once.

4 files changed, 40 insertions, 39 deletions

diff --git a/src/csharp/GrpcCore/Channel.cs b/src/csharp/GrpcCore/Channel.cs
index b0d8beeb7b..36ebef777f 100644
--- a/src/csharp/GrpcCore/Channel.cs
+++ b/src/csharp/GrpcCore/Channel.cs
@@ -8,13 +8,6 @@ namespace Google.GRPC.Core
 {
 	public class Channel : IDisposable
 	{
-        /// <summary>
-        /// Make sure GPRC environment is initialized before any channels get used.
-        /// </summary>
-        static Channel() {
-            GrpcEnvironment.EnsureInitialized();
-        }
-       
         readonly ChannelSafeHandle handle;
         readonly String target;
 
diff --git a/src/csharp/GrpcCore/GrpcEnvironment.cs b/src/csharp/GrpcCore/GrpcEnvironment.cs
index 7a7ff39179..dcd3bc672b 100644
--- a/src/csharp/GrpcCore/GrpcEnvironment.cs
+++ b/src/csharp/GrpcCore/GrpcEnvironment.cs
@@ -5,11 +5,9 @@ using System.Runtime.InteropServices;
 namespace Google.GRPC.Core
 {
     /// <summary>
-    /// Encapsulates initialization and shutdown of GRPC C core library.
-    /// You should not need to initialize it manually, as static constructors
-    /// should load the library when needed.
+    /// Encapsulates initialization and shutdown of gRPC library.
     /// </summary>
-    public static class GrpcEnvironment
+    public class GrpcEnvironment
     {
         const int THREAD_POOL_SIZE = 1;
 
@@ -20,21 +18,24 @@ namespace Google.GRPC.Core
         static extern void grpcsharp_shutdown();
 
         static object staticLock = new object();
-        static bool initCalled = false;
-        static bool shutdownCalled = false;
-
-        static GrpcThreadPool threadPool = new GrpcThreadPool(THREAD_POOL_SIZE);
+        static volatile GrpcEnvironment instance;
+       
+        readonly GrpcThreadPool threadPool;
+        bool isClosed;
 
         /// <summary>
-        /// Makes sure GRPC environment is initialized.
+        /// Makes sure GRPC environment is initialized. Subsequent invocations don't have any
+        /// effect unless you call Shutdown first.
+        /// Although normal use cases assume you will call this just once in your application's
+        /// lifetime (and call Shutdown once you're done), for the sake of easier testing it's 
+        /// allowed to initialize the environment again after it has been successfully shutdown.
         /// </summary>
-        public static void EnsureInitialized() {
+        public static void Initialize() {
             lock(staticLock)
             {
-                if (!initCalled)
+                if (instance == null)
                 {
-                    initCalled = true;
-                    GrpcInit();       
+                    instance = new GrpcEnvironment();
                 }
             }
         }
@@ -47,45 +48,55 @@ namespace Google.GRPC.Core
         {
             lock(staticLock)
             {
-                if (initCalled && !shutdownCalled)
+                if (instance != null)
                 {
-                    shutdownCalled = true;
-                    GrpcShutdown();
+                    instance.Close();
+                    instance = null;
                 }
             }
+        }
 
+        internal static GrpcThreadPool ThreadPool
+        {
+            get
+            {
+                var inst = instance;
+                if (inst == null)
+                {
+                    throw new InvalidOperationException("GRPC environment not initialized");
+                }
+                return inst.threadPool;
+            }
         }
 
         /// <summary>
-        /// Initializes GRPC C Core library.
+        /// Creates gRPC environment.
         /// </summary>
-        private static void GrpcInit()
+        private GrpcEnvironment()
         {
             grpcsharp_init();
+            threadPool = new GrpcThreadPool(THREAD_POOL_SIZE);
             threadPool.Start();
             // TODO: use proper logging here
             Console.WriteLine("GRPC initialized.");
         }
 
         /// <summary>
-        /// Shutdown GRPC C Core library.
+        /// Shuts down this environment.
         /// </summary>
-        private static void GrpcShutdown()
+        private void Close()
         {
+            if (isClosed)
+            {
+                throw new InvalidOperationException("Close has already been called");
+            }
             threadPool.Stop();
             grpcsharp_shutdown();
+            isClosed = true;
 
             // TODO: use proper logging here
             Console.WriteLine("GRPC shutdown.");
         }
-
-        internal static GrpcThreadPool ThreadPool
-        {
-            get
-            {
-                return threadPool;
-            }
-        }
     }
 }
 
diff --git a/src/csharp/GrpcCore/Server.cs b/src/csharp/GrpcCore/Server.cs
index d3bc81e574..3c4a73aa7a 100644
--- a/src/csharp/GrpcCore/Server.cs
+++ b/src/csharp/GrpcCore/Server.cs
@@ -26,10 +26,6 @@ namespace Google.GRPC.Core
 
         readonly TaskCompletionSource<object> shutdownTcs = new TaskCompletionSource<object>();
 
-        static Server() {
-            GrpcEnvironment.EnsureInitialized();
-        }
-
         public Server()
         {
             // TODO: what is the tag for server shutdown?
diff --git a/src/csharp/GrpcCore/Utils/RecordingQueue.cs b/src/csharp/GrpcCore/Utils/RecordingQueue.cs
index 0726f00af7..81e1a8298f 100644
--- a/src/csharp/GrpcCore/Utils/RecordingQueue.cs
+++ b/src/csharp/GrpcCore/Utils/RecordingQueue.cs
@@ -5,6 +5,7 @@ using System.Collections.Concurrent;
 
 namespace Google.GRPC.Core.Utils
 {
+    // TODO: replace this by something that implements IAsyncEnumerator.
     /// <summary>
     /// Observer that allows us to await incoming messages one-by-one.
     /// The implementation is not ideal and class will be probably replaced