first attempt to add python interpreter lock. Not working

src/Bonsai.Scripting.Python/Bonsai.Scripting.Python.csproj

@@ -5,7 +5,7 @@
     <Description>Bonsai Scripting Library for interfacing with the Python runtime.</Description>
     <PackageTags>Bonsai Rx Scripting Python Python.NET</PackageTags>
     <TargetFramework>net472</TargetFramework>
-    <VersionPrefix>0.1.0</VersionPrefix>
+    <VersionPrefix>0.2.0</VersionPrefix>
     <LangVersion>8.0</LangVersion>
   </PropertyGroup>
 

src/Bonsai.Scripting.Python/GilManager.cs

@@ -0,0 +1,20 @@
+using Python.Runtime;
+using System;
+
+public sealed class GilManager
+{
+    private static readonly Lazy<GilManager> _instance = new Lazy<GilManager>(() => new GilManager());
+    public static GilManager Instance => _instance.Value;
+
+    private GilManager()
+    {
+    }
+
+    public void ExecuteWithGil(Action action)
+    {
+        using (Py.GIL()) // Acquire GIL
+        {
+            action();
+        }
+    }
+}

src/Bonsai.Scripting.Python/PythonInterpreterLock.cs

@@ -12,6 +12,7 @@ namespace Bonsai.Scripting.Python
     public class PythonInterpreterLock : WorkflowExpressionBuilder
     {
         static readonly Range<int> argumentRange = Range.Create(lowerBound: 1, upperBound: 1);
+        private static readonly object _lock = new object();
 
         public PythonInterpreterLock()
             : this(new ExpressionBuilderGraph())
@@ -27,44 +28,36 @@ public PythonInterpreterLock(ExpressionBuilderGraph workflow)
 
         public override Expression Build(IEnumerable<Expression> arguments)
         {
-            // var source = arguments.Single();
-            // var sourceType = source.Type.GetGenericArguments()[0]; // Get TSource from IObservable<TSource>
-            // var factoryParameter = Expression.Parameter(typeof(IObservable<>).MakeGenericType(sourceType));
-            Console.WriteLine($"here1 args: {arguments}");
             var source = arguments.FirstOrDefault();
             if (source == null)
             {
                 throw new InvalidOperationException("There must be at least one input.");
             }
             var sourceType = source.Type.GetGenericArguments()[0]; // Get TSource from IObservable<TSource>
-            Console.WriteLine($"here2 sourceType: {source.Type}");
-            // var factoryParameter = Expression.Parameter(source.Type);
             var factoryParameter = Expression.Parameter(typeof(IObservable<>).MakeGenericType(sourceType), "factoryParam");
-            Console.WriteLine($"here3 factoryParam: {factoryParameter}");
+
             return BuildWorkflow(arguments, factoryParameter, selectorBody =>
             {
-                Console.WriteLine($"here4 selectorBody: {selectorBody}");
                 var selector = Expression.Lambda(selectorBody, factoryParameter);
-                Console.WriteLine($"here5 selector: {selector}");
                 var resultType = selectorBody.Type.GetGenericArguments()[0];
-                Console.WriteLine($"here6 resultType: {resultType}");
-                // var processMethod = typeof(PythonInterpreterLock).GetMethod(nameof(Process)).MakeGenericMethod(sourceType, resultType);
-                // Console.WriteLine($"here7 processMethod: {processMethod}");
-                // return Expression.Call(processMethod, source, selector);
                 return Expression.Call(GetType(), nameof(Process), new Type[] {sourceType, resultType}, source, selector);
             });
         }
 
         static IObservable<TResult> Process<TSource, TResult>(IObservable<TSource> source, Func<IObservable<TSource>, IObservable<TResult>> selector)
         {
-            Console.WriteLine("process");
-            return Observable.Defer(() =>
+            lock(_lock)
             {
-                using (Py.GIL())
+                return source.SelectMany(value =>
                 {
-                    return selector(source);
-                }
-            });
+                    using (Py.GIL())
+                    {
+                        return selector(Observable.Return(value));
+                        // );
+                    }
+                });
+            }
+            // return result;
         }
     }
 }

src/Bonsai.Scripting.Python/RuntimeManager.cs

@@ -28,10 +28,7 @@ internal RuntimeManager(string pythonHome, string scriptPath, IObserver<RuntimeM
             {
                 Initialize(pythonHome);
                 threadState = PythonEngine.BeginAllowThreads();
-                using (Py.GIL())
-                {
-                    MainModule = CreateModule(scriptPath: scriptPath);
-                }
+                MainModule = CreateModule(scriptPath: scriptPath);
                 observer.OnNext(this);
             });
         }

src/Bonsai.Scripting.Python/Set.cs

@@ -49,11 +49,11 @@ public override IObservable<TSource> Process<TSource>(IObservable<TSource> sourc
             {
                 return source.Do(value =>
                 {
-                    using (Py.GIL())
-                    {
+                    // using (Py.GIL())
+                    // {
                         var module = Module ?? runtime.MainModule;
                         module.Set(VariableName, value);
-                    }
+                    // }
                 });
             });
         }