Adding a log event when reading .autorest_generated.json file (Azure#…

…6746)

* Adding a log event when reading .autorest_generated.json file
The change is to generate a log event when the `.autorest_generated.json` file exists in any existing function app. This file is added by stencil plugins and need to be sent to inform us how many deployed function apps have been generated by Stencil plugins.

src/WebJobs.Script/Diagnostics/Extensions/LoggerExtension.cs

@@ -3,6 +3,7 @@
 
 using System;
 using Microsoft.Extensions.Logging;
+using static System.Environment;
 
 namespace Microsoft.Azure.WebJobs.Script.Diagnostics.Extensions
 {
@@ -206,7 +207,19 @@ internal static class LoggerExtension
             LoggerMessage.Define(
             LogLevel.Information,
             new EventId(331, nameof(JobHostFunctionTimeoutNotSet)),
-            "FunctioTimeout is not set.");
+            "FunctionTimeout is not set.");
+
+        private static readonly Action<ILogger, string, Exception> _autorestGeneratedFunctionApplication =
+            LoggerMessage.Define<string>(
+            LogLevel.Information,
+            new EventId(332, nameof(AutorestGeneratedFunctionApplication)),
+            "autorest_generated.json file found generated by Autorest (https://aka.ms/stencil) | file content:\n{sanitizedAutorestJson}");
+
+        private static readonly Action<ILogger, string, Exception> _incorrectAutorestGeneratedJSONFile =
+            LoggerMessage.Define<string>(
+            LogLevel.Warning,
+            new EventId(333, nameof(IncorrectAutorestGeneratedJsonFile)),
+            "autorest_generated.json file found is incorrect (https://aka.ms/stencil) | exception:\n{contents}");
 
         public static void ExtensionsManagerRestoring(this ILogger logger)
         {
@@ -379,5 +392,15 @@ public static void JobHostFunctionTimeoutNotSet(this ILogger logger)
         {
             _jobHostFunctionTimeoutNotSet(logger, null);
         }
+
+        public static void AutorestGeneratedFunctionApplication(this ILogger logger, string sanitizedAutorestJson)
+        {
+            _autorestGeneratedFunctionApplication(logger, sanitizedAutorestJson, null);
+        }
+
+        public static void IncorrectAutorestGeneratedJsonFile(this ILogger logger, string contents)
+        {
+            _incorrectAutorestGeneratedJSONFile(logger, contents, null);
+        }
     }
 }

src/WebJobs.Script/Host/ScriptHost.cs

@@ -295,6 +295,8 @@ public async Task InitializeAsync(CancellationToken cancellationToken = default)
                     }
 
                     _metricsLogger.LogEvent(string.Format(MetricEventNames.HostStartupRuntimeLanguage, runtimeStack));
+
+                    Utility.LogAutorestGeneratedJsonIfExists(ScriptOptions.RootScriptPath, _logger);
                 }
 
                 var directTypes = GetDirectTypes(functionMetadataList);

src/WebJobs.Script/ScriptConstants.cs

@@ -73,6 +73,7 @@ public static class ScriptConstants
         public const string DiagnosticSentinelFileName = "diagnostic_sentinel";
         public const string HostMetadataFileName = "host.json";
         public const string FunctionMetadataFileName = "function.json";
+        public const string AutorestGeenratedMetadataFileName = ".autorest_generated.json";
         public const string ProxyMetadataFileName = "proxies.json";
         public const string ExtensionsMetadataFileName = "extensions.json";
         public const string AppOfflineFileName = "app_offline.htm";

src/WebJobs.Script/Utility.cs

@@ -18,6 +18,7 @@
 using Microsoft.Azure.WebJobs.Host;
 using Microsoft.Azure.WebJobs.Logging;
 using Microsoft.Azure.WebJobs.Script.Description;
+using Microsoft.Azure.WebJobs.Script.Diagnostics.Extensions;
 using Microsoft.Azure.WebJobs.Script.Workers.Rpc;
 using Microsoft.Extensions.Logging;
 using Newtonsoft.Json;
@@ -796,6 +797,33 @@ public static void ValidateRetryOptions(RetryOptions
             }
         }
 
+        public static void LogAutorestGeneratedJsonIfExists(string rootScriptPath, ILogger logger)
+        {
+            string autorestGeneratedJsonPath = Path.Combine(rootScriptPath, ScriptConstants.AutorestGeenratedMetadataFileName);
+            JObject autorestGeneratedJson;
+
+            if (FileUtility.FileExists(autorestGeneratedJsonPath))
+            {
+                string autorestGeneratedJsonPathContents = FileUtility.ReadAllText(autorestGeneratedJsonPath);
+                try
+                {
+                    autorestGeneratedJson = JObject.Parse(autorestGeneratedJsonPathContents);
+                    logger.AutorestGeneratedFunctionApplication(autorestGeneratedJson.ToString());
+                }
+                catch (JsonException ex)
+                {
+                    logger.IncorrectAutorestGeneratedJsonFile($"Unable to parse autorest configuration file '{autorestGeneratedJsonPath}'" +
+                        $" with content '{autorestGeneratedJsonPathContents}' | exception: {ex.StackTrace}");
+                }
+                catch (Exception ex)
+                {
+                    logger.IncorrectAutorestGeneratedJsonFile($"Caught exception while parsing .autorest_generated.json | " +
+                        $"exception: {ex.StackTrace}");
+                }
+            }
+            // If we dont find the .autorest_generated.json in the function app, we just don't log anything.
+        }
+
         private class FilteredExpandoObjectConverter : ExpandoObjectConverter
         {
             public override bool CanWrite => true;

test/WebJobs.Script.Tests/UtilityTests.cs

@@ -6,12 +6,15 @@
 using System.Diagnostics;
 using System.Dynamic;
 using System.Globalization;
+using System.IO;
 using System.IO.Abstractions;
+using System.Linq;
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Azure.WebJobs.Logging;
 using Microsoft.Azure.WebJobs.Script.Description;
+using Microsoft.Extensions.Logging;
 using Microsoft.WebJobs.Script.Tests;
 using Moq;
 using Newtonsoft.Json.Linq;
@@ -50,6 +53,8 @@ public class TestPocoEx : TestPoco
 
     public class UtilityTests
     {
+        private TestLogger _testLogger = new TestLogger("test");
+
         [Fact]
         public async Task InvokeWithRetriesAsync_Throws_WhenRetryCountExceeded()
         {
@@ -595,5 +600,54 @@ public void TryGetFunctionName_ReturnsExpectedResult(string keyName, bool expect
                 Assert.Equal("test", functionName);
             }
         }
+
+        [Fact]
+        public async Task Test_LogAutorestGeneratedJson_Without_AutorestGeneratedJson()
+        {
+            string functionAppDirectory = GetTemporaryDirectory();
+            try
+            {
+                Utility.LogAutorestGeneratedJsonIfExists(functionAppDirectory, _testLogger);
+                var allLogs = _testLogger.GetLogMessages();
+                Assert.Empty(allLogs);
+            }
+            finally
+            {
+                await FileUtility.DeleteDirectoryAsync(functionAppDirectory, true);
+            }
+        }
+
+        [Theory]
+        [InlineData("{\"name\":\"@autorest/azure-functions-csharp\",\"version\":\"0.2.0-preview\"}", "autorest_generated.json file found generated by Autorest (https://aka.ms/stencil) | file content", LogLevel.Information)]
+        [InlineData("{\"name\":\"@autorest/azure-functions-csharp\",\"version\"\"0.2.0-preview\"}", "autorest_generated.json file found is incorrect (https://aka.ms/stencil) | exception", LogLevel.Warning)]
+        public async Task Test_LogAutorestGeneratedJson_With_AutorestGeneratedJson(string autorestGeneratedJsonContent, string expectedContents, LogLevel expectedLogLevel)
+        {
+            string functionAppDirectory = GetTemporaryDirectory();
+            try
+            {
+                File.WriteAllText(Path.Combine(functionAppDirectory, ScriptConstants.AutorestGeenratedMetadataFileName), autorestGeneratedJsonContent);
+                Utility.LogAutorestGeneratedJsonIfExists(functionAppDirectory, _testLogger);
+                var allLogs = _testLogger.GetLogMessages();
+                VerifyLogLevel(allLogs, expectedContents, expectedLogLevel);
+            }
+            finally
+            {
+                await FileUtility.DeleteDirectoryAsync(functionAppDirectory, true);
+            }
+        }
+
+        private static void VerifyLogLevel(IList<LogMessage> allLogs, string msg, LogLevel expectedLevel)
+        {
+            var message = allLogs.Where(l => l.FormattedMessage.Contains(msg)).FirstOrDefault();
+            Assert.NotNull(message);
+            Assert.Equal(expectedLevel, message.Level);
+        }
+
+        private static string GetTemporaryDirectory()
+        {
+            string tempDirectory = Path.Combine(Path.GetTempPath(), Path.GetRandomFileName());
+            FileUtility.EnsureDirectoryExists(tempDirectory);
+            return tempDirectory;
+        }
     }
 }