adding SystemLogger to WebHost; filtering based on allowed categories

sample/host.json

@@ -9,8 +9,8 @@
         "counterThreshold": 0.80
     },
     "functionTimeout": "00:05:00",
-    "logger": {
-        "fileLoggingMode": "always"
+    "logging": {
+        "fileLoggingMode": "always"        
     },
     "swagger": {
         "enabled": true

src/WebJobs.Script.WebHost/Diagnostics/ILoggingBuilderExtensions.cs

@@ -0,0 +1,19 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT License. See License.txt in the project root for license information.
+
+using Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Microsoft.Extensions.Logging
+{
+    public static class ILoggingBuilderExtensions
+    {
+        public static void AddWebJobsSystem<T>(this ILoggingBuilder builder) where T : SystemLoggerProvider
+        {
+            builder.Services.AddSingleton<ILoggerProvider, T>();
+
+            // Log all logs to SystemLogger
+            builder.AddDefaultWebJobsFilters<T>(LogLevel.Trace);
+        }
+    }
+}

src/WebJobs.Script.WebHost/Diagnostics/MetricsEventManager.cs

@@ -7,7 +7,6 @@
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
-using Microsoft.Azure.WebJobs.Script.Config;
 using Microsoft.Azure.WebJobs.Script.Description;
 using Microsoft.Azure.WebJobs.Script.Diagnostics;
 using Microsoft.Azure.WebJobs.Script.WebHost.Models;
@@ -23,16 +22,16 @@ public class MetricsEventManager : IDisposable
         private readonly IEventGenerator _eventGenerator;
         private readonly int _functionActivityFlushIntervalSeconds;
         private readonly Timer _metricsFlushTimer;
-        private object _functionActivityTrackerLockObject = new object();
+        private readonly object _functionActivityTrackerLockObject = new object();
         private static string appName;
         private static string subscriptionId;
         private bool _disposed;
 
-        public MetricsEventManager(ScriptSettingsManager settingsManager, IEventGenerator generator, int functionActivityFlushIntervalSeconds, int metricsFlushIntervalMS = DefaultFlushIntervalMS)
+        public MetricsEventManager(IEnvironment environment, IEventGenerator generator, int functionActivityFlushIntervalSeconds, int metricsFlushIntervalMS = DefaultFlushIntervalMS)
         {
             // we read these in the ctor (not static ctor) since it can change on the fly
-            appName = GetNormalizedString(settingsManager.AzureWebsiteUniqueSlotName);
-            subscriptionId = Utility.GetSubscriptionId(settingsManager) ?? string.Empty;
+            appName = GetNormalizedString(environment.GetAzureWebsiteUniqueSlotName());
+            subscriptionId = environment.GetSubscriptionId() ?? string.Empty;
 
             _eventGenerator = generator;
             _functionActivityFlushIntervalSeconds = functionActivityFlushIntervalSeconds;
@@ -497,8 +496,7 @@ private List<FunctionMetrics> GetMetricsQueueSnapshot()
 
                 for (int iterator = 0; iterator < currentQueueLength; iterator++)
                 {
-                    FunctionMetrics queueItem;
-                    if (_functionMetricsQueue.TryDequeue(out queueItem))
+                    if (_functionMetricsQueue.TryDequeue(out FunctionMetrics queueItem))
                     {
                         queueSnapshot.Add(queueItem);
                     }

src/WebJobs.Script.WebHost/Diagnostics/SystemLogger.cs

@@ -5,27 +5,22 @@
 using System.Collections.Generic;
 using Microsoft.Azure.WebJobs.Host;
 using Microsoft.Azure.WebJobs.Logging;
-using Microsoft.Azure.WebJobs.Script.Config;
 using Microsoft.Extensions.Logging;
 
 namespace Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics
 {
     public class SystemLogger : ILogger
     {
         private readonly IEventGenerator _eventGenerator;
-        private readonly ScriptSettingsManager _settingsManager;
-        private readonly string _appName;
-        private readonly string _subscriptionId;
         private readonly string _categoryName;
         private readonly string _functionName;
         private readonly bool _isUserFunction;
         private readonly string _hostInstanceId;
+        private readonly IEnvironment _environment;
 
-        public SystemLogger(string hostInstanceId, string categoryName, IEventGenerator eventGenerator, ScriptSettingsManager settingsManager)
+        public SystemLogger(string hostInstanceId, string categoryName, IEventGenerator eventGenerator, IEnvironment environment)
         {
-            _settingsManager = settingsManager;
-            _appName = _settingsManager.AzureWebsiteUniqueSlotName;
-            _subscriptionId = Utility.GetSubscriptionId(settingsManager);
+            _environment = environment;
             _eventGenerator = eventGenerator;
             _categoryName = categoryName ?? string.Empty;
             _functionName = LogCategories.IsFunctionCategory(_categoryName) ? _categoryName.Split('.')[1] : string.Empty;
@@ -74,8 +69,8 @@ public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Except
             // Apply standard event properties
             // Note: we must be sure to default any null values to empty string
             // otherwise the ETW event will fail to be persisted (silently)
-            string subscriptionId = _subscriptionId ?? string.Empty;
-            string appName = _appName ?? string.Empty;
+            string subscriptionId = _environment.GetSubscriptionId() ?? string.Empty;
+            string appName = _environment.GetAzureWebsiteUniqueSlotName() ?? string.Empty;
             string source = _categoryName ?? Utility.GetValueFromState(state, ScriptConstants.LogPropertySourceKey);
             string summary = Sanitizer.Sanitize(formattedMessage) ?? string.Empty;
             string innerExceptionType = string.Empty;

src/WebJobs.Script.WebHost/Diagnostics/SystemLoggerProvider.cs

@@ -3,7 +3,6 @@
 
 using System;
 using Microsoft.Azure.WebJobs.Logging;
-using Microsoft.Azure.WebJobs.Script.Config;
 using Microsoft.Azure.WebJobs.Script.Rpc;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
@@ -14,14 +13,19 @@ namespace Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics
     public class SystemLoggerProvider : ILoggerProvider
     {
         private readonly string _hostInstanceId;
-        private IEventGenerator _eventGenerator;
-        private ScriptSettingsManager _settingsManager;
+        private readonly IEventGenerator _eventGenerator;
+        private readonly IEnvironment _environment;
 
-        public SystemLoggerProvider(IOptions<ScriptJobHostOptions> scriptOptions, IEventGenerator eventGenerator, ScriptSettingsManager settingsManager)
+        public SystemLoggerProvider(IOptions<ScriptJobHostOptions> scriptOptions, IEventGenerator eventGenerator, IEnvironment environment)
+            : this(scriptOptions.Value.InstanceId, eventGenerator, environment)
+        {
+        }
+
+        protected SystemLoggerProvider(string hostInstanceId, IEventGenerator eventGenerator, IEnvironment environment)
         {
             _eventGenerator = eventGenerator;
-            _settingsManager = settingsManager;
-            _hostInstanceId = scriptOptions.Value.InstanceId;
+            _environment = environment;
+            _hostInstanceId = hostInstanceId;
         }
 
         public ILogger CreateLogger(string categoryName)
@@ -31,7 +35,7 @@ public ILogger CreateLogger(string categoryName)
             {
                 return NullLogger.Instance;
             }
-            return new SystemLogger(_hostInstanceId, categoryName, _eventGenerator, _settingsManager);
+            return new SystemLogger(_hostInstanceId, categoryName, _eventGenerator, _environment);
         }
 
         private bool IsUserLogCategory(string categoryName)

src/WebJobs.Script.WebHost/Diagnostics/WebHostMetricsLogger.cs

@@ -2,7 +2,6 @@
 // Licensed under the MIT License. See License.txt in the project root for license information.
 
 using System;
-using Microsoft.Azure.WebJobs.Script.Config;
 using Microsoft.Azure.WebJobs.Script.Diagnostics;
 
 namespace Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics
@@ -12,13 +11,8 @@ public class WebHostMetricsLogger : IMetricsLogger, IDisposable
         private readonly MetricsEventManager _metricsEventManager;
         private bool disposed = false;
 
-        public WebHostMetricsLogger()
-            : this(ScriptSettingsManager.Instance, new EtwEventGenerator(), 5)
-        {
-        }
-
-        public WebHostMetricsLogger(IEventGenerator eventGenerator)
-            : this(ScriptSettingsManager.Instance, eventGenerator, 5)
+        public WebHostMetricsLogger(IEnvironment environment, IEventGenerator eventGenerator)
+            : this(environment, eventGenerator, 5)
         {
         }
 
@@ -27,9 +21,9 @@ public WebHostMetricsLogger(MetricsEventManager eventManager)
             _metricsEventManager = eventManager;
         }
 
-        protected WebHostMetricsLogger(ScriptSettingsManager settingsManager, IEventGenerator eventGenerator, int metricEventIntervalInSeconds)
+        protected WebHostMetricsLogger(IEnvironment environment, IEventGenerator eventGenerator, int metricEventIntervalInSeconds)
         {
-            _metricsEventManager = new MetricsEventManager(settingsManager, eventGenerator, metricEventIntervalInSeconds);
+            _metricsEventManager = new MetricsEventManager(environment, eventGenerator, metricEventIntervalInSeconds);
         }
 
         public object BeginEvent(string eventName, string functionName = null)
@@ -62,7 +56,7 @@ public void EndEvent(MetricEvent metricEvent)
             }
             else
             {
-                _metricsEventManager.EndEvent((object)metricEvent);
+                _metricsEventManager.EndEvent(metricEvent);
             }
         }
 

src/WebJobs.Script.WebHost/Diagnostics/WebHostSystemLoggerProvider.cs

@@ -0,0 +1,17 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT License. See License.txt in the project root for license information.
+
+namespace Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics
+{
+    /// <summary>
+    /// A SystemLoggerProvider that can be registered at the WebHost level. It logs with an empty InstanceId
+    /// to make it clear that it is not a part of a JobHost.
+    /// </summary>
+    public class WebHostSystemLoggerProvider : SystemLoggerProvider
+    {
+        public WebHostSystemLoggerProvider(IEventGenerator eventGenerator, IEnvironment environment)
+            : base(string.Empty, eventGenerator, environment)
+        {
+        }
+    }
+}

src/WebJobs.Script.WebHost/Program.cs

@@ -6,6 +6,7 @@
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Azure.WebJobs.Script.WebHost.Configuration;
 using Microsoft.Azure.WebJobs.Script.WebHost.DependencyInjection;
+using Microsoft.Azure.WebJobs.Script.WebHost.Diagnostics;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Configuration.EnvironmentVariables;
 using Microsoft.Extensions.DependencyInjection;
@@ -18,8 +19,16 @@ public class Program
     {
         public static void Main(string[] args)
         {
-            BuildWebHost(args)
-                .RunAsync()
+            var host = BuildWebHost(args);
+
+            var environment = host.Services.GetService<IEnvironment>();
+            if (environment.IsLinuxContainerEnvironment())
+            {
+                // Linux containers always start out in placeholder mode
+                environment.SetEnvironmentVariable(EnvironmentSettingNames.AzureWebsitePlaceholderMode, "1");
+            }
+
+            host.RunAsync()
                 .Wait();
         }
 
@@ -57,7 +66,13 @@ public static IWebHostBuilder CreateWebHostBuilder(string[] args = null)
                         IsLinuxContainerEnvironment = SystemEnvironment.Instance.IsLinuxContainerEnvironment()
                     });
                 })
-                .ConfigureLogging(b => b.ClearProviders())
+                .ConfigureLogging((context, loggingBuilder) =>
+                {
+                    loggingBuilder.ClearProviders();
+
+                    loggingBuilder.AddDefaultWebJobsFilters();
+                    loggingBuilder.AddWebJobsSystem<WebHostSystemLoggerProvider>();
+                })
                 .UseStartup<Startup>();
         }
     }

src/WebJobs.Script.WebHost/Startup.cs

@@ -31,17 +31,9 @@ public void Configure(IApplicationBuilder app, IApplicationLifetime applicationL
         {
             if (env.IsDevelopment())
             {
-                loggerFactory.AddConsole(LogLevel.Trace, true);
                 app.UseDeveloperExceptionPage();
             }
 
-            var environment = app.ApplicationServices.GetService<IEnvironment>();
-            if (environment.IsLinuxContainerEnvironment())
-            {
-                // Linux containers always start out in placeholder mode
-                environment.SetEnvironmentVariable(EnvironmentSettingNames.AzureWebsitePlaceholderMode, "1");
-            }
-
             app.UseWebJobsScriptHost(applicationLifetime);
         }
     }

src/WebJobs.Script.WebHost/WebScriptHostBuilderExtension.cs

@@ -12,7 +12,6 @@
 using Microsoft.Extensions.DependencyInjection.Extensions;
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Options;
 
 namespace Microsoft.Azure.WebJobs.Script.WebHost
 {
@@ -41,7 +40,8 @@ public static IHostBuilder AddWebScriptHost(this IHostBuilder builder, IServiceP
                 .ConfigureLogging(loggingBuilder =>
                 {
                     loggingBuilder.Services.AddSingleton<ILoggerFactory, ScriptLoggerFactory>();
-                    loggingBuilder.Services.AddSingleton<ILoggerProvider, SystemLoggerProvider>();
+
+                    loggingBuilder.AddWebJobsSystem<SystemLoggerProvider>();
 
                     ConfigureRegisteredBuilders(loggingBuilder, rootServiceProvider);
                 })

src/WebJobs.Script/Environment/EnvironmentExtensions.cs

@@ -67,6 +67,24 @@ public static string GetAzureWebsiteUniqueSlotName(this IEnvironment environment
             return name?.ToLowerInvariant();
         }
 
+        /// <summary>
+        /// Gets a the subscription Id of the current site.
+        /// </summary>
+        public static string GetSubscriptionId(this IEnvironment environment)
+        {
+            string ownerName = environment.GetEnvironmentVariable(AzureWebsiteOwnerName) ?? string.Empty;
+            if (!string.IsNullOrEmpty(ownerName))
+            {
+                int idx = ownerName.IndexOf('+');
+                if (idx > 0)
+                {
+                    return ownerName.Substring(0, idx);
+                }
+            }
+
+            return null;
+        }
+
         public static bool IsContainerReady(this IEnvironment environment)
         {
             return !string.IsNullOrEmpty(environment.GetEnvironmentVariable(AzureWebsiteContainerReady));