Changing default compilation optimization level to release

Author: fabiocav

src/WebJobs.Script/Description/DotNet/DotNetCompilationServiceFactory.cs

@@ -27,23 +27,39 @@ ImmutableArray<ScriptType> ICompilationServiceFactory.SupportedScriptTypes
             }
         }
 
-        private static OptimizationLevel OptimizationLevel
+        private static bool IsLocal => string.IsNullOrEmpty(Environment.GetEnvironmentVariable(EnvironmentSettingNames.AzureWebsiteInstanceId));
+
+        private static bool IsRemoteDebuggingEnabled => !string.IsNullOrEmpty(Environment.GetEnvironmentVariable(EnvironmentSettingNames.RemoteDebuggingPort));
+
+        internal static OptimizationLevel OptimizationLevel
         {
             get
             {
                 if (_optimizationLevel == null)
                 {
-                    string releaseModeSetting = Environment.GetEnvironmentVariable(DotNetConstants.CompilationReleaseMode);
+                    // Get the release mode setting. If set, this will take priority over environment settings.
+                    string releaseModeSetting = Environment.GetEnvironmentVariable(EnvironmentSettingNames.CompilationReleaseMode);
+
+                    bool releaseMode;
+                    if (!bool.TryParse(releaseModeSetting, out releaseMode) && !IsLocal && !IsRemoteDebuggingEnabled)
+                    {
+                        // If the release mode setting is not set, we're running in Azure
+                        // and not remote debugging, use release mode.
+                        releaseMode = true;
+                    }
 
-                    _optimizationLevel = string.Equals(releaseModeSetting, bool.TrueString, StringComparison.OrdinalIgnoreCase)
-                        ? OptimizationLevel.Release
-                        : OptimizationLevel.Debug;
+                    _optimizationLevel = releaseMode ? OptimizationLevel.Release : OptimizationLevel.Debug;
                 }
 
                 return _optimizationLevel.Value;
             }
         }
 
+        internal static void SetOptimizationLevel(OptimizationLevel? level)
+        {
+            _optimizationLevel = level;
+        }
+
         public ICompilationService CreateService(ScriptType scriptType, IFunctionMetadataResolver metadataResolver)
         {
             switch (scriptType)
@@ -53,7 +69,7 @@ public ICompilationService CreateService(ScriptType scriptType, IFunctionMetadat
                 case ScriptType.FSharp:
                     return new FSharpCompiler(metadataResolver, OptimizationLevel);
                 default:
-                    throw new NotSupportedException(string.Format(CultureInfo.InvariantCulture, 
+                    throw new NotSupportedException(string.Format(CultureInfo.InvariantCulture,
                         "The script type {0} is not supported by the {1}", scriptType, typeof(DotNetCompilationServiceFactory).Name));
             }
         }

src/WebJobs.Script/Description/DotNet/DotNetConstants.cs

@@ -16,7 +16,5 @@ public static class DotNetConstants
         public const string RedundantPackageAssemblyReference = "AF005";
         public const string InvalidFileMetadataReferenceCode = "AF006";
         public const string InvalidEntryPointNameCompilationCode = "AF007";
-
-        public const string CompilationReleaseMode = "AzureWebJobsDotNetReleaseCompilation";
     }
 }

src/WebJobs.Script/EnvironmentSettingNames.cs

@@ -11,8 +11,10 @@ public static class EnvironmentSettingNames
         public const string AzureWebsiteOwnerName = "WEBSITE_OWNER_NAME";
         public const string AzureWebsiteInstanceId = "WEBSITE_INSTANCE_ID";
         public const string AzureWebsiteSku = "WEBSITE_SKU";
+        public const string RemoteDebuggingPort = "REMOTEDEBUGGINGPORT";
         public const string AzureWebsitePlaceholderMode = "WEBSITE_PLACEHOLDER_MODE";
         public const string AzureWebsiteHomePath = "HOME";
         public const string AzureWebJobsScriptRoot = "AzureWebJobsScriptRoot";
+        public const string CompilationReleaseMode = "AzureWebJobsDotNetReleaseCompilation";
     }
 }

test/WebJobs.Script.Tests/Description/DotNet/DotNetCompilationServiceFactoryTests.cs

@@ -0,0 +1,73 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT License. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.Azure.WebJobs.Script.Description;
+using Microsoft.CodeAnalysis;
+using Xunit;
+
+namespace Microsoft.Azure.WebJobs.Script.Tests.Description.DotNet
+{
+    public class DotNetCompilationServiceFactoryTests
+    {
+        [Fact]
+        public void OptimizationLevel_CompilationReleaseModeSetToTrue_ReturnsRelease()
+        {
+            ResetOptimizationFlag();
+
+            using (var variables = new TestScopedEnvironmentVariables(EnvironmentSettingNames.CompilationReleaseMode, "True"))
+            {
+                Assert.Equal(OptimizationLevel.Release, DotNetCompilationServiceFactory.OptimizationLevel);
+            }
+        }
+
+        [Fact]
+        public void OptimizationLevel_CompilationReleaseModeSetToFalse_ReturnsDebug()
+        {
+            ResetOptimizationFlag();
+
+            using (var variables = new TestScopedEnvironmentVariables(EnvironmentSettingNames.CompilationReleaseMode, "False"))
+            {
+                Assert.Equal(OptimizationLevel.Debug, DotNetCompilationServiceFactory.OptimizationLevel);
+            }
+        }
+
+        [Fact]
+        public void OptimizationLevel_WhenRemote_ReturnsRelease()
+        {
+            ResetOptimizationFlag();
+
+            using (var variables = new TestScopedEnvironmentVariables(EnvironmentSettingNames.AzureWebsiteInstanceId, "123"))
+            {
+                Assert.Equal(OptimizationLevel.Release, DotNetCompilationServiceFactory.OptimizationLevel);
+            }
+        }
+
+        [Fact]
+        public void OptimizationLevel_WhenRemoteWithRemoteDebugging_ReturnsDebug()
+        {
+            ResetOptimizationFlag();
+
+            var variables = new Dictionary<string, string>
+            {
+                { EnvironmentSettingNames.AzureWebsiteInstanceId, "123" },
+                { EnvironmentSettingNames.RemoteDebuggingPort, "1234" }
+            };
+
+            using (new TestScopedEnvironmentVariables(variables))
+            {
+                Assert.Equal(OptimizationLevel.Debug, DotNetCompilationServiceFactory.OptimizationLevel);
+            }
+        }
+
+        private void ResetOptimizationFlag()
+        {
+            DotNetCompilationServiceFactory.SetOptimizationLevel(null);
+        }
+    }
+}

test/WebJobs.Script.Tests/WebJobs.Script.Tests.csproj

@@ -413,6 +413,7 @@
     <Compile Include="CSharpEndToEndTests.cs" />
     <Compile Include="CSharpFunctionSignatureTests.cs" />
     <Compile Include="Description\DotNet\CSharp\CSharpCompilationTests.cs" />
+    <Compile Include="Description\DotNet\DotNetCompilationServiceFactoryTests.cs" />
     <Compile Include="Description\DotNet\FunctionAssemblyLoaderTests.cs" />
     <Compile Include="Description\DotNet\DotNetFunctionInvokerTests.cs" />
     <Compile Include="Description\DotNet\PackageManagerTests.cs" />