Log outgoing HTTP path parameters in Structured mode

src/Libraries/Microsoft.Extensions.Http.Diagnostics/Logging/Internal/HttpRequestReader.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
+using System.Buffers;
 using System.Collections.Frozen;
 using System.Collections.Generic;
 using System.Net.Http;
@@ -19,6 +20,7 @@ namespace Microsoft.Extensions.Http.Logging.Internal;
 internal sealed class HttpRequestReader : IHttpRequestReader
 {
     private readonly IHttpRouteFormatter _routeFormatter;
+    private readonly IHttpRouteParser _httpRouteParser;
     private readonly IHttpHeadersReader _httpHeadersReader;
     private readonly FrozenDictionary<string, DataClassification> _defaultSensitiveParameters;
 
@@ -44,12 +46,14 @@ public HttpRequestReader(
         IServiceProvider serviceProvider,
         IOptionsMonitor<LoggingOptions> optionsMonitor,
         IHttpRouteFormatter routeFormatter,
+        IHttpRouteParser httpRouteParser,
         IOutgoingRequestContext requestMetadataContext,
         IDownstreamDependencyMetadataManager? downstreamDependencyMetadataManager = null,
         [ServiceKey] string? serviceKey = null)
         : this(
               optionsMonitor.GetKeyedOrCurrent(serviceKey),
               routeFormatter,
+              httpRouteParser,
               serviceProvider.GetRequiredOrKeyedRequiredService<IHttpHeadersReader>(serviceKey),
               requestMetadataContext,
               downstreamDependencyMetadataManager)
@@ -59,6 +63,7 @@ public HttpRequestReader(
     internal HttpRequestReader(
         LoggingOptions options,
         IHttpRouteFormatter routeFormatter,
+        IHttpRouteParser httpRouteParser,
         IHttpHeadersReader httpHeadersReader,
         IOutgoingRequestContext requestMetadataContext,
         IDownstreamDependencyMetadataManager? downstreamDependencyMetadataManager = null)
@@ -67,6 +72,7 @@ internal HttpRequestReader(
         _httpHeadersReader = httpHeadersReader;
 
         _routeFormatter = routeFormatter;
+        _httpRouteParser = httpRouteParser;
         _requestMetadataContext = requestMetadataContext;
         _downstreamDependencyMetadataManager = downstreamDependencyMetadataManager;
 
@@ -92,7 +98,7 @@ public async Task ReadRequestAsync(LogRecord logRecord, HttpRequestMessage reque
     {
         logRecord.Host = request.RequestUri?.Host ?? TelemetryConstants.Unknown;
         logRecord.Method = request.Method;
-        logRecord.Path = GetRedactedPath(request);
+        GetRedactedPathAndParameters(request, logRecord);
 
         if (_logRequestHeaders)
         {
@@ -125,16 +131,19 @@ public async Task ReadResponseAsync(LogRecord logRecord, HttpResponseMessage res
         logRecord.StatusCode = (int)response.StatusCode;
     }
 
-    private string GetRedactedPath(HttpRequestMessage request)
+    private void GetRedactedPathAndParameters(HttpRequestMessage request, LogRecord logRecord)
     {
+        logRecord.PathParameters = null;
         if (request.RequestUri is null)
         {
-            return TelemetryConstants.Unknown;
+            logRecord.Path = TelemetryConstants.Unknown;
+            return;
         }
 
         if (_routeParameterRedactionMode == HttpRouteParameterRedactionMode.None)
         {
-            return request.RequestUri.AbsolutePath;
+            logRecord.Path = request.RequestUri.AbsolutePath;
+            return;
         }
 
         var requestMetadata = request.GetRequestMetadata() ??
@@ -143,19 +152,36 @@ private string GetRedactedPath(HttpRequestMessage request)
 
         if (requestMetadata == null)
         {
-            return TelemetryConstants.Redacted;
+            logRecord.Path = TelemetryConstants.Redacted;
+            return;
         }
 
         var route = requestMetadata.RequestRoute;
         if (route == TelemetryConstants.Unknown)
         {
-            return requestMetadata.RequestName;
+            logRecord.Path = requestMetadata.RequestName;
+            return;
         }
 
-        return _outgoingPathLogMode switch
+        var routeSegments = _httpRouteParser.ParseRoute(route);
+
+        if (_outgoingPathLogMode == OutgoingPathLoggingMode.Formatted)
+        {
+            logRecord.Path = _routeFormatter.Format(in routeSegments, request.RequestUri.AbsolutePath, _routeParameterRedactionMode, _defaultSensitiveParameters);
+            logRecord.PathParameters = null;
+        }
+        else
         {
-            OutgoingPathLoggingMode.Formatted => _routeFormatter.Format(route, request.RequestUri.AbsolutePath, _routeParameterRedactionMode, _defaultSensitiveParameters),
-            _ => route
-        };
+            // Case when logging mode is "OutgoingPathLoggingMode.Structured"
+            logRecord.Path = route;
+            var routeParams = ArrayPool<HttpRouteParameter>.Shared.Rent(routeSegments.ParameterCount);
+
+            // Setting this value right away to be able to return it back to pool in a callee's "finally" block:
+            logRecord.PathParameters = routeParams;
+            if (_httpRouteParser.TryExtractParameters(request.RequestUri.AbsolutePath, in routeSegments, _routeParameterRedactionMode, _defaultSensitiveParameters, ref routeParams))
+            {
+                logRecord.PathParametersCount = routeSegments.ParameterCount;
+            }
+        }
     }
 }

src/Libraries/Microsoft.Extensions.Http.Diagnostics/Logging/Internal/Log.cs

@@ -34,7 +34,7 @@ internal static class Log
         "An error occurred in enricher '{Enricher}' while enriching the logger context for request: " +
         $"{{{HttpClientLoggingTagNames.Method}}} {{{HttpClientLoggingTagNames.Host}}}/{{{HttpClientLoggingTagNames.Path}}}";
 
-    private static readonly Func<LoggerMessageState, Exception?, string> _originalFormatValueFMTFunc = OriginalFormatValueFMT;
+    private static readonly Func<LoggerMessageState, Exception?, string> _originalFormatValueFMTFunc = OriginalFormatValueFmt;
 
     public static void OutgoingRequest(ILogger logger, LogLevel level, LogRecord record)
     {
@@ -115,7 +115,7 @@ public static void LoggerContextMissing(ILogger logger, Exception? exception, st
             new(0, nameof(LoggerContextMissing)),
             state,
             exception,
-            (s, _) =>
+            static (s, _) =>
             {
                 var requestState = s.TagArray[3].Value ?? NullString;
                 var method = s.TagArray[2].Value ?? NullString;
@@ -142,7 +142,7 @@ public static void EnrichmentError(ILogger logger, Exception exception, string?
             new(0, nameof(EnrichmentError)),
             state,
             exception,
-            (s, _) =>
+            static (s, _) =>
             {
                 var enricher = s.TagArray[4].Value ?? NullString;
                 var method = s.TagArray[3].Value ?? NullString;
@@ -171,7 +171,10 @@ private static void OutgoingRequest(
         var requestHeadersCount = record.RequestHeaders?.Count ?? 0;
         var responseHeadersCount = record.ResponseHeaders?.Count ?? 0;
 
-        var index = loggerMessageState.ReserveTagSpace(MinimalPropertyCount + statusCodePropertyCount + requestHeadersCount + responseHeadersCount);
+        var spaceToReserve = MinimalPropertyCount + statusCodePropertyCount + requestHeadersCount + responseHeadersCount +
+            record.PathParametersCount + (record.RequestBody is null ? 0 : 1) + (record.ResponseBody is null ? 0 : 1);
+
+        var index = loggerMessageState.ReserveTagSpace(spaceToReserve);
         loggerMessageState.TagArray[index++] = new(HttpClientLoggingTagNames.Method, record.Method);
         loggerMessageState.TagArray[index++] = new(HttpClientLoggingTagNames.Host, record.Host);
         loggerMessageState.TagArray[index++] = new(HttpClientLoggingTagNames.Path, record.Path);
@@ -192,14 +195,19 @@ private static void OutgoingRequest(
             loggerMessageState.AddResponseHeaders(record.ResponseHeaders!, ref index);
         }
 
+        if (record.PathParameters is not null)
+        {
+            loggerMessageState.AddPathParameters(record.PathParameters, record.PathParametersCount, ref index);
+        }
+
         if (record.RequestBody is not null)
         {
-            loggerMessageState.AddTag(HttpClientLoggingTagNames.RequestBody, record.RequestBody);
+            loggerMessageState.TagArray[index++] = new(HttpClientLoggingTagNames.RequestBody, record.RequestBody);
         }
 
         if (record.ResponseBody is not null)
         {
-            loggerMessageState.AddTag(HttpClientLoggingTagNames.ResponseBody, record.ResponseBody);
+            loggerMessageState.TagArray[index] = new(HttpClientLoggingTagNames.ResponseBody, record.ResponseBody);
         }
 
         logger.Log(
@@ -215,7 +223,7 @@ private static void OutgoingRequest(
         }
     }
 
-    private static string OriginalFormatValueFMT(LoggerMessageState request, Exception? _)
+    private static string OriginalFormatValueFmt(LoggerMessageState request, Exception? _)
     {
         int startIndex = FindStartIndex(request);
         var httpMethod = request[startIndex].Value;

src/Libraries/Microsoft.Extensions.Http.Diagnostics/Logging/Internal/LogRecord.cs

@@ -1,8 +1,10 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Buffers;
 using System.Collections.Generic;
 using System.Net.Http;
+using Microsoft.Extensions.Http.Diagnostics;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.ObjectPool;
 
@@ -63,8 +65,24 @@ internal sealed class LogRecord : IResettable
     /// </summary>
     public LoggerMessageState? EnrichmentTags { get; set; }
 
+    /// <summary>
+    /// Gets or sets request path parameters.
+    /// </summary>
+    public HttpRouteParameter[]? PathParameters { get; set; }
+
+    /// <summary>
+    /// Gets or sets request path parameters count for <see cref="PathParameters"/>.
+    /// </summary>
+    public int PathParametersCount { get; set; }
+
     public bool TryReset()
     {
+        if (PathParameters != null)
+        {
+            ArrayPool<HttpRouteParameter>.Shared.Return(PathParameters);
+            PathParameters = null;
+        }
+
         Host = string.Empty;
         Method = null;
         Path = string.Empty;
@@ -75,6 +93,7 @@ public bool TryReset()
         EnrichmentTags = null;
         RequestHeaders = null;
         ResponseHeaders = null;
+        PathParametersCount = 0;
         return true;
     }
 }

src/Libraries/Microsoft.Extensions.Http.Diagnostics/Logging/Internal/LoggerMessageStateExtensions.cs

@@ -4,6 +4,7 @@
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using Microsoft.Extensions.Http.Diagnostics;
 using Microsoft.Extensions.Logging;
 
 namespace Microsoft.Extensions.Http.Logging.Internal;
@@ -26,8 +27,7 @@ public static void AddRequestHeaders(this LoggerMessageState state, List<KeyValu
         {
             var key = _requestPrefixedNamesCache.GetOrAdd(
                 items[i].Key,
-                static (x, p) => p + Normalize(x),
-                HttpClientLoggingTagNames.RequestHeaderPrefix);
+                static x => HttpClientLoggingTagNames.RequestHeaderPrefix + Normalize(x));
 
             state.TagArray[index++] = new(key, items[i].Value);
         }
@@ -46,17 +46,30 @@ public static void AddResponseHeaders(this LoggerMessageState state, List<KeyVal
         {
             var key = _responsePrefixedNamesCache.GetOrAdd(
                 items[i].Key,
-                static (x, p) => p + Normalize(x),
-                HttpClientLoggingTagNames.ResponseHeaderPrefix);
+                static x => HttpClientLoggingTagNames.ResponseHeaderPrefix + Normalize(x));
 
             state.TagArray[index++] = new(key, items[i].Value);
         }
     }
 
+    /// <summary>
+    /// Adds path parameters to <see cref="LoggerMessageState"/>.
+    /// </summary>
+    /// <param name="state">A <see cref="LoggerMessageState"/> to be filled.</param>
+    /// <param name="parameters">An array with path parameters.</param>
+    /// <param name="paramsCount">A number of path parameters.</param>
+    /// <param name="index">Represents an index to be used when writing tags into <paramref name="state"/>.</param>
+    /// <remarks><paramref name="index"/> will be mutated to point to the next <paramref name="state"/> item.</remarks>
+    public static void AddPathParameters(this LoggerMessageState state, HttpRouteParameter[] parameters, int paramsCount, ref int index)
+    {
+        for (var i = 0; i < paramsCount; i++)
+        {
+            state.TagArray[index++] = new(parameters[i].Name, parameters[i].Value);
+        }
+    }
+
     [SuppressMessage("Globalization", "CA1308:Normalize strings to uppercase",
         Justification = "Normalization to lower case is required by OTel's semantic conventions")]
     private static string Normalize(string header)
-    {
-        return header.ToLowerInvariant();
-    }
+        => header.ToLowerInvariant();
 }

src/Libraries/Microsoft.Extensions.Http.Diagnostics/Microsoft.Extensions.Http.Diagnostics.csproj

@@ -42,6 +42,7 @@
     <PackageReference Include="Microsoft.Extensions.Http" />
     <PackageReference Include="System.Text.Json" />
     <PackageReference Include="System.Collections.Immutable" Condition="!$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net8.0'))" />
+    <PackageReference Include="System.Net.Http" Condition="'$(TargetFramework)' == 'net462'" />
   </ItemGroup>
 
   <ItemGroup>

src/Libraries/Microsoft.Extensions.Telemetry/Http/HttpRouteFormatter.cs

@@ -15,7 +15,7 @@ internal sealed class HttpRouteFormatter : IHttpRouteFormatter
 {
     private const char ForwardSlashSymbol = '/';
 
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
     private const char ForwardSlash = ForwardSlashSymbol;
 #else
 #pragma warning disable IDE1006 // Naming Styles

src/Libraries/Microsoft.Extensions.Telemetry/Http/IHttpRouteParser.cs

@@ -28,12 +28,10 @@ internal interface IHttpRouteParser
     /// <param name="parametersToRedact">Dictionary of parameters with their data classification that needs to be redacted.</param>
     /// <param name="httpRouteParameters">Output array where parameters will be stored. Caller must provide the array with enough capacity to hold all parameters in route segment.</param>
     /// <returns>Returns true if parameters were extracted successfully, return false otherwise.</returns>
-#pragma warning disable CA1045 // Do not pass types by reference
     bool TryExtractParameters(
         string httpPath,
         in ParsedRouteSegments routeSegments,
         HttpRouteParameterRedactionMode redactionMode,
         IReadOnlyDictionary<string, DataClassification> parametersToRedact,
         ref HttpRouteParameter[] httpRouteParameters);
-#pragma warning restore CA1045 // Do not pass types by reference
 }

src/Libraries/Microsoft.Extensions.Telemetry/Microsoft.Extensions.Telemetry.csproj

@@ -24,7 +24,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\..\Libraries\Microsoft.Extensions.DependencyInjection.AutoActivation\Microsoft.Extensions.DependencyInjection.AutoActivation.csproj" />
+    <ProjectReference Include="..\Microsoft.Extensions.DependencyInjection.AutoActivation\Microsoft.Extensions.DependencyInjection.AutoActivation.csproj" />
     <ProjectReference Include="..\Microsoft.Extensions.AmbientMetadata.Application\Microsoft.Extensions.AmbientMetadata.Application.csproj" />
     <ProjectReference Include="..\Microsoft.Extensions.Compliance.Abstractions\Microsoft.Extensions.Compliance.Abstractions.csproj" />
     <ProjectReference Include="..\Microsoft.Extensions.Telemetry.Abstractions\Microsoft.Extensions.Telemetry.Abstractions.csproj" />