Switch to module approach (#20)

* Switch to module approach

* misc comment updates

* resolve rebase conflicts

* address dongbo's feedback

* Add new line to end

* use Import-Module and misc feedback

* just set the module path

* fully qualified, no more useLocalScopes

Author: TylerLeonhardt

README.md

@@ -11,9 +11,9 @@ Prototype for Azure Functions PowerShell Language Worker
 ```powershell
 # Windows if you installed the Azure Functions Core Tools via npm
 Remove-Item -Recurse -Force ~\AppData\Roaming\npm\node_modules\azure-functions-core-tools\bin\workers\powershell
-Copy-Item src\Azure.Functions.PowerShell.Worker\bin\Debug\netcoreapp2.1\publish ~\AppData\Roaming\npm\node_modules\azure-functions-core-tools\bin\workers\powershell -Recurse -Force
+Copy-Item src\bin\Debug\netcoreapp2.1\publish ~\AppData\Roaming\npm\node_modules\azure-functions-core-tools\bin\workers\powershell -Recurse -Force
 
 # macOS if you installed the Azure Functions Core Tools via brew
 Remove-Item -Recurse -Force /usr/local/Cellar/azure-functions-core-tools/2.0.1-beta.33/workers/powershell
-Copy-Item src/Azure.Functions.PowerShell.Worker/bin/Debug/netcoreapp2.1/publish /usr/local/Cellar/azure-functions-core-tools/2.0.1-beta.33/workers/powershell -Recurse -Force
+Copy-Item src/bin/Debug/netcoreapp2.1/publish /usr/local/Cellar/azure-functions-core-tools/2.0.1-beta.33/workers/powershell -Recurse -Force
 ```

examples/PSCoreApp/MyHttpTrigger/run.ps1

@@ -1,10 +1,8 @@
-param($req, $TriggerMetadata)
-
-# Write-Host $TriggerMetadata["Name"]
-
 # Invoked with Invoke-RestMethod:
 # irm http://localhost:7071/api/MyHttpTrigger?Name=Tyler
-# Input bindings are added to the scope of the script: ex. `$req`
+# Input bindings are added via param block
+
+param($req, $TriggerMetadata)
 
 # If no name was passed by query parameter
 $name = 'World'
@@ -22,7 +20,7 @@ Write-Warning "Warning $name"
 $name
 
 # You set the value of your output bindings by assignment `$nameOfOutputBinding = 'foo'`
-$res = [HttpResponseContext]@{
+Push-OutputBinding -Name res -Value ([HttpResponseContext]@{
     Body = @{ Hello = $name }
     ContentType = 'application/json'
-}
+})

src/Modules/Azure.Functions.PowerShell.Worker.Module/Azure.Functions.PowerShell.Worker.Module.psm1

@@ -30,7 +30,10 @@ function Get-OutputBinding {
     param(
         [Parameter(ValueFromPipeline = $True, ValueFromPipelineByPropertyName = $True)]
         [string[]]
-        $Name = '*'
+        $Name = '*',
+
+        [switch]
+        $Purge
     )
     begin {
         $bindings = @{}
@@ -39,6 +42,9 @@ function Get-OutputBinding {
         $script:_OutputBindings.GetEnumerator() | Where-Object Name -Like $Name | ForEach-Object { $null = $bindings.Add($_.Name, $_.Value) }
     }
     end {
+        if($Purge.IsPresent) {
+            $script:_OutputBindings.Clear()
+        }
         return $bindings
     }
 }

src/PowerShell/PowerShellExtensions.cs

@@ -0,0 +1,27 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System.Collections.ObjectModel;
+
+namespace Microsoft.Azure.Functions.PowerShellWorker.PowerShell
+{
+    using System.Management.Automation;
+
+    internal static class PowerShellExtensions
+    {
+        public static void InvokeAndClearCommands(this PowerShell pwsh)
+        {
+            pwsh.Invoke();
+            pwsh.Commands.Clear();
+        }
+
+        public static Collection<T> InvokeAndClearCommands<T>(this PowerShell pwsh)
+        {
+            var result = pwsh.Invoke<T>();
+            pwsh.Commands.Clear();
+            return result;
+        }
+    }
+}

src/PowerShell/PowerShellManager.cs

@@ -7,7 +7,7 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
-using System.Text;
+using System.IO;
 
 using Microsoft.Azure.Functions.PowerShellWorker.Utility;
 using Microsoft.Azure.WebJobs.Script.Grpc.Messages;
@@ -20,33 +20,16 @@ namespace Microsoft.Azure.Functions.PowerShellWorker.PowerShell
 
     internal class PowerShellManager
     {
-        // This script handles when the user adds something to the pipeline.
-        // It logs the item that comes and stores it as the $return out binding.
-        // The last item stored as $return will be returned to the function host.
+        private const string _TriggerMetadataParameterName = "TriggerMetadata";
 
-        readonly static string s_LogAndSetReturnValueScript = @"
-param([Parameter(ValueFromPipeline=$true)]$return)
+        private RpcLogger _logger;
+        private PowerShell _pwsh;
 
-Write-Information $return
-
-Set-Variable -Name '$return' -Value $return -Scope global
-";
-
-        readonly static string s_SetExecutionPolicyOnWindowsScript = @"
-if ($IsWindows)
-{
-    Set-ExecutionPolicy -ExecutionPolicy Unrestricted -Scope Process
-}
-";
-
-        readonly static string s_TriggerMetadataParameterName = "TriggerMetadata";
-
-        RpcLogger _logger;
-        PowerShell _pwsh;
-
-        PowerShellManager(RpcLogger logger)
+        internal PowerShellManager(RpcLogger logger)
         {
-            _pwsh = PowerShell.Create(InitialSessionState.CreateDefault());
+            var initialSessionState = InitialSessionState.CreateDefault();
+            initialSessionState.ExecutionPolicy = Microsoft.PowerShell.ExecutionPolicy.Unrestricted;
+            _pwsh = PowerShell.Create(initialSessionState);
             _logger = logger;
 
             // Setup Stream event listeners
@@ -59,64 +42,17 @@ internal class PowerShellManager
             _pwsh.Streams.Warning.DataAdding += streamHandler.WarningDataAdding;
         }
 
-        public static PowerShellManager Create(RpcLogger logger)
-        {                
-            var manager = new PowerShellManager(logger);
-
+        internal void InitializeRunspace()
+        {
             // Add HttpResponseContext namespace so users can reference
             // HttpResponseContext without needing to specify the full namespace
-            manager.ExecuteScriptAndClearCommands($"using namespace {typeof(HttpResponseContext).Namespace}");
-            manager.ExecuteScriptAndClearCommands(s_SetExecutionPolicyOnWindowsScript);
-            return manager;
-        }
-
-        static string BuildBindingHashtableScript(IDictionary<string, BindingInfo> outBindings)
-        {
-            // Since all of the out bindings are stored in variables at this point,
-            // we must construct a script that will return those output bindings in a hashtable
-            StringBuilder script = new StringBuilder();
-            script.AppendLine("@{");
-            foreach (KeyValuePair<string, BindingInfo> binding in outBindings)
-            {
-                script.Append("'");
-                script.Append(binding.Key);
-
-                // since $return has a dollar sign, we have to treat it differently
-                if (binding.Key == "$return")
-                {
-                    script.Append("' = ");
-                }
-                else
-                {
-                    script.Append("' = $");
-                }
-                script.AppendLine(binding.Key);
-            }
-            script.AppendLine("}");
-
-            return script.ToString();
-        }
-
-        void ResetRunspace()
-        {
-            // Reset the runspace to the Initial Session State
-            _pwsh.Runspace.ResetRunspaceState();
+            _pwsh.AddScript($"using namespace {typeof(HttpResponseContext).Namespace}").InvokeAndClearCommands();
+            
+            // Set the PSModulePath
+            Environment.SetEnvironmentVariable("PSModulePath", Path.Join(AppDomain.CurrentDomain.BaseDirectory, "Modules"));
         }
 
-        void ExecuteScriptAndClearCommands(string script)
-        {
-            _pwsh.AddScript(script).Invoke();
-            _pwsh.Commands.Clear();
-        }
-
-        public Collection<T> ExecuteScriptAndClearCommands<T>(string script)
-        {
-            var result = _pwsh.AddScript(script).Invoke<T>();
-            _pwsh.Commands.Clear();
-            return result;
-        }
-
-        public PowerShellManager InvokeFunctionAndSetGlobalReturn(
+        internal Hashtable InvokeFunction(
             string scriptPath,
             string entryPoint,
             Hashtable triggerMetadata,
@@ -130,20 +66,25 @@ public PowerShellManager InvokeFunctionAndSetGlobalReturn(
                 // If it does, we invoke the command of that name. We also need to fetch
                 // the ParameterMetadata so that we can tell whether or not the user is asking
                 // for the $TriggerMetadata
-
                 using (ExecutionTimer.Start(_logger, "Parameter metadata retrieved."))
                 {
                     if (entryPoint != "")
                     {
-                        ExecuteScriptAndClearCommands($@". {scriptPath}");
-                        parameterMetadata = ExecuteScriptAndClearCommands<FunctionInfo>($@"Get-Command {entryPoint}")[0].Parameters;
-                        _pwsh.AddScript($@". {entryPoint} @args");
+                        parameterMetadata = _pwsh
+                            .AddCommand("Microsoft.PowerShell.Core\\Import-Module").AddParameter("Name", scriptPath)
+                            .AddStatement()
+                            .AddCommand("Microsoft.PowerShell.Core\\Get-Command").AddParameter("Name", entryPoint)
+                            .InvokeAndClearCommands<FunctionInfo>()[0].Parameters;
+
+                        _pwsh.AddCommand(entryPoint);
 
                     }
                     else
                     {
-                        parameterMetadata = ExecuteScriptAndClearCommands<ExternalScriptInfo>($@"Get-Command {scriptPath}")[0].Parameters;
-                        _pwsh.AddScript($@". {scriptPath} @args");
+                        parameterMetadata = _pwsh.AddCommand("Microsoft.PowerShell.Core\\Get-Command").AddParameter("Name", scriptPath)
+                            .InvokeAndClearCommands<ExternalScriptInfo>()[0].Parameters;
+
+                        _pwsh.AddCommand(scriptPath);
                     }
                 }
 
@@ -154,41 +95,52 @@ public PowerShellManager InvokeFunctionAndSetGlobalReturn(
                 }
 
                 // Gives access to additional Trigger Metadata if the user specifies TriggerMetadata
-                if(parameterMetadata.ContainsKey(s_TriggerMetadataParameterName))
+                if(parameterMetadata.ContainsKey(_TriggerMetadataParameterName))
                 {
-                    _pwsh.AddParameter(s_TriggerMetadataParameterName, triggerMetadata);
+                    _pwsh.AddParameter(_TriggerMetadataParameterName, triggerMetadata);
                     _logger.LogDebug($"TriggerMetadata found. Value:{Environment.NewLine}{triggerMetadata.ToString()}");
                 }
 
-                // This script handles when the user adds something to the pipeline.
+                PSObject returnObject = null;
                 using (ExecutionTimer.Start(_logger, "Execution of the user's function completed."))
                 {
-                    ExecuteScriptAndClearCommands(s_LogAndSetReturnValueScript);
+                    // Log everything we received from the pipeline and set the last one to be the ReturnObject
+                    Collection<PSObject> pipelineItems = _pwsh.InvokeAndClearCommands<PSObject>();
+                    foreach (var psobject in pipelineItems)
+                    {
+                        _logger.LogInformation($"OUTPUT: {psobject.ToString()}");
+                    }
+                    
+                    returnObject = pipelineItems[pipelineItems.Count - 1];
+                }
+                
+                var result = _pwsh.AddCommand("Azure.Functions.PowerShell.Worker.Module\\Get-OutputBinding")
+                    .AddParameter("Purge")
+                    .InvokeAndClearCommands<Hashtable>()[0];
+
+                if(returnObject != null)
+                {
+                    result.Add("$return", returnObject);
                 }
-                return this;
+                return result;
             }
-            catch(Exception e)
+            finally
             {
-                ResetRunspace();
-                throw e;
+                ResetRunspace(scriptPath);
             }
         }
 
-        public Hashtable ReturnBindingHashtable(IDictionary<string, BindingInfo> outBindings)
+        private void ResetRunspace(string scriptPath)
         {
-            try
-            {
-                // This script returns a hashtable that contains the
-                // output bindings that we will return to the function host.
-                var result = ExecuteScriptAndClearCommands<Hashtable>(BuildBindingHashtableScript(outBindings))[0];
-                ResetRunspace();
-                return result;
-            }
-            catch(Exception e)
-            {
-                ResetRunspace();
-                throw e;
-            }
+            // Reset the runspace to the Initial Session State
+            _pwsh.Runspace.ResetRunspaceState();
+
+            // If the function had an entry point, this will remove the module that was loaded
+            var moduleName = Path.GetFileNameWithoutExtension(scriptPath);
+            _pwsh.AddCommand("Microsoft.PowerShell.Core\\Remove-Module")
+                .AddParameter("Name", moduleName)
+                .AddParameter("ErrorAction", "SilentlyContinue")
+                .InvokeAndClearCommands();
         }
     }
 }

src/RequestProcessor.cs

@@ -26,7 +26,7 @@ internal RequestProcessor(MessagingStream msgStream)
         {
             _msgStream = msgStream;
             _logger = new RpcLogger(msgStream);
-            _powerShellManager = PowerShellManager.Create(_logger);
+            _powerShellManager = new PowerShellManager(_logger);
             _functionLoader = new FunctionLoader();
         }
 
@@ -63,15 +63,27 @@ internal async Task ProcessRequestLoop()
 
         internal StreamingMessage ProcessWorkerInitRequest(StreamingMessage request)
         {
+            StatusResult status = new StatusResult()
+            {
+                Status = StatusResult.Types.Status.Success
+            };
+
+            try
+            {
+                _powerShellManager.InitializeRunspace();
+            }
+            catch (Exception e)
+            {
+                status.Status = StatusResult.Types.Status.Failure;
+                status.Exception = e.ToRpcException();
+            }
+
             return new StreamingMessage()
             {
                 RequestId = request.RequestId,
                 WorkerInitResponse = new WorkerInitResponse()
                 {
-                    Result = new StatusResult()
-                    {
-                        Status = StatusResult.Types.Status.Success
-                    }
+                    Result = status
                 }
             };
         }
@@ -143,8 +155,7 @@ internal StreamingMessage ProcessInvocationRequest(StreamingMessage request)
             try
             {
                 result = _powerShellManager
-                    .InvokeFunctionAndSetGlobalReturn(scriptPath, entryPoint, triggerMetadata, invocationRequest.InputData)
-                    .ReturnBindingHashtable(functionInfo.OutputBindings);
+                    .InvokeFunction(scriptPath, entryPoint, triggerMetadata, invocationRequest.InputData);
             }
             catch (Exception e)
             {