Add infrastructure to support multiple execution environments

RemoteExec.Server/Utilities/AssemblyUtilities.cs

@@ -0,0 +1,40 @@
+using System.Reflection;
+
+namespace RemoteExec.Server.Utilities;
+
+public static class AssemblyUtilities
+{
+    public static async Task PreLoadReferencedAssembliesAsync(RemoteJobAssemblyLoadContext assemblyLoadContext, Assembly assembly, Func<string, Task<byte[]>> requestAssembly)
+    {
+        AssemblyName[] referencedAssemblies = assembly.GetReferencedAssemblies();
+
+        foreach (AssemblyName referencedAssembly in referencedAssemblies)
+        {
+            // Try to load from the assembly load context first
+            Assembly? loadedAssembly = assemblyLoadContext.Assemblies.FirstOrDefault(a => a.GetName().FullName == referencedAssembly.FullName);
+
+            if (loadedAssembly != null)
+            {
+                continue; // Already loaded in the context
+            }
+
+            // Try to load from default context (BCL assemblies)
+            try
+            {
+                _ = assemblyLoadContext.LoadFromAssemblyName(referencedAssembly);
+                continue; // Successfully loaded from default context
+            }
+            catch
+            {
+                byte[] assemblyBytes = await requestAssembly(referencedAssembly.FullName!);
+                _ = assemblyLoadContext.LoadFromBytes(assemblyBytes);
+            }
+        }
+    }
+
+    public static Assembly LoadFromBytes(this RemoteJobAssemblyLoadContext assemblyLoadContext, byte[] assemblyBytes)
+    {
+        using MemoryStream ms = new(assemblyBytes);
+        return assemblyLoadContext.LoadFromStream(ms);
+    }
+}