Manage caching options: EnableHeadersHashing vs CleanableHashingRegexes

src/Ocelot/Cache/DefaultCacheKeyGenerator.cs

@@ -28,19 +28,41 @@ public async ValueTask<string> GenerateRequestCacheKey(DownstreamRequest downstr
             }
         }
 
-        if (!options.EnableContentHashing || !downstreamRequest.HasContent)
+        if (!options.EnableHeadersHashing && !options.EnableContentHashing && !downstreamRequest.HasContent)
         {
             return MD5Helper.GenerateMd5(builder.ToString());
         }
 
-        var requestContentString = await ReadContentAsync(downstreamRequest);
-        builder.Append(Delimiter)
-            .Append(requestContentString);
+        if (options.EnableContentHashing)
+        {
+            var requestContentString = await ReadContentAsync(downstreamRequest);
+            builder.Append(Delimiter)
+                .Append(requestContentString);
+        }
+
+        if (options.EnableHeadersHashing)
+        {
+            var requestHeadersString = await ReadHeadersAsync(downstreamRequest);
+            builder.Append(Delimiter)
+                .Append(requestHeadersString);
+        }
+
+        if (options.CleanableHashingRegexes.Any())
+        {
+            return MD5Helper.GenerateMd5(HashingClean(builder.ToString(), options.CleanableHashingRegexes));
+        }
 
         return MD5Helper.GenerateMd5(builder.ToString());
     }
 
+    private static string HashingClean(string input, List<string> patterns) =>
+        patterns.Aggregate(input, (current, pattern) => Regex.Replace(current, pattern, string.Empty, RegexOptions.Singleline));
+
     private static Task<string> ReadContentAsync(DownstreamRequest downstream) => downstream.HasContent
         ? downstream?.Request?.Content?.ReadAsStringAsync() ?? Task.FromResult(string.Empty)
         : Task.FromResult(string.Empty);
+
+    private static Task<string> ReadHeadersAsync(DownstreamRequest downstream) => downstream.HasContent
+        ? Task.FromResult(string.Join(":", downstream?.Headers.Select(h => h.Key + "=" + string.Join(",", h.Value))))
+        : Task.FromResult(string.Empty);
 }

src/Ocelot/Configuration/CacheOptions.cs

@@ -19,13 +19,17 @@ internal CacheOptions() { }
     /// <param name="ttlSeconds">Time-to-live seconds. If not speciefied, zero value is used by default.</param>
     /// <param name="region">The region of caching.</param>
     /// <param name="header">The header name to control cached value.</param>
-    /// <param name="enableContentHashing">The switcher for content hashing. If not speciefied, false value is used by default.</param>
-    public CacheOptions(int? ttlSeconds, string region, string header, bool? enableContentHashing)
+    /// <param name="enableContentHashing">The switcher for content hashing. If not speciefied, false value is used by default.</param>
+    /// <param name="enableHeadersHashing">The switcher for headers hashing. If not speciefied, false value is used by default.</param>
+    /// <param name="cleanableHashingRegexes">The list of regex patterns to clean the hash. If not speciefied, an empty list is used by default.</param></param>
+    public CacheOptions(int? ttlSeconds, string region, string header, bool? enableContentHashing, bool? enableHeadersHashing, List<string>? cleanableHashingRegexes)
     {
         TtlSeconds = ttlSeconds ?? 0;
         Region = region;
         Header = header;
         EnableContentHashing = enableContentHashing ?? false;
+        EnableHeadersHashing = enableHeadersHashing ?? false;
+        CleanableHashingRegexes = cleanableHashingRegexes ?? new();
     }
 
     /// <summary>Time-to-live seconds.</summary>
@@ -39,4 +43,14 @@ public CacheOptions(int? ttlSeconds, string region, string header, bool? enableC
     /// <remarks>Default value is <see langword="false"/>. No hashing by default.</remarks>
     /// <value><see langword="true"/> if hashing is enabled, otherwise it is <see langword="false"/>.</value>
     public bool EnableContentHashing { get; }
+
+    /// <summary>Enables MD5 hash calculation of the <see cref="HttpRequestMessage.Headers"/> of the <see cref="DownstreamRequest.Request"/> object.</summary>
+    /// <remarks>Default value is <see langword="false"/>. No hashing by default.</remarks>
+    /// <value><see langword="true"/> if hashing is enabled, otherwise it is <see langword="false"/>.</value>
+    public bool EnableHeadersHashing { get; }
+
+    /// <summary>The list of regex patterns to clean the hash.</summary>
+    /// <remarks>Default value is an empty list. No cleaning by default.</remarks>
+    /// <value>A <see cref="List{T}"/> of <see cref="string"/> values.</value>
+    public List<string> CleanableHashingRegexes { get; }
 }

src/Ocelot/Configuration/Creator/CacheOptionsCreator.cs

@@ -10,8 +10,10 @@ public CacheOptions Create(FileCacheOptions options, FileGlobalConfiguration glo
         var header = options.Header ?? global?.CacheOptions.Header;
         var ttlSeconds = options.TtlSeconds ?? global?.CacheOptions.TtlSeconds;
         var enableContentHashing = options.EnableContentHashing ?? global?.CacheOptions.EnableContentHashing;
+        var enableHeadersHashing = options.EnableHeadersHashing ?? global?.CacheOptions.EnableHeadersHashing;
+        var cleanableHashingRegexes = options.CleanableHashingRegexes ?? global?.CacheOptions.CleanableHashingRegexes;
 
-        return new CacheOptions(ttlSeconds, region, header, enableContentHashing);
+        return new CacheOptions(ttlSeconds, region, header, enableContentHashing, enableHeadersHashing, cleanableHashingRegexes);
     }
 
     protected virtual string GetRegion(string region, string upstreamPathTemplate, IList<string> upstreamHttpMethod)

src/Ocelot/Configuration/File/FileCacheOptions.cs

@@ -10,6 +10,8 @@ public FileCacheOptions(FileCacheOptions from)
         TtlSeconds = from.TtlSeconds;
         Header = from.Header;
         EnableContentHashing = from.EnableContentHashing;
+        EnableHeadersHashing = from.EnableHeadersHashing;
+        CleanableHashingRegexes = from.CleanableHashingRegexes;
     }
 
     /// <summary>Using <see cref="Nullable{T}"/> where T is <see cref="int"/> to have <see langword="null"/> as default value and allowing global configuration usage.</summary>
@@ -23,4 +25,14 @@ public FileCacheOptions(FileCacheOptions from)
     /// <remarks>If <see langword="null"/> then use global configuration with <see langword="false"/> by default.</remarks>
     /// <value><see langword="true"/> if content hashing is enabled; otherwise, <see langword="false"/>.</value>
     public bool? EnableContentHashing { get; set; }
+
+    /// <summary>Using <see cref="Nullable{T}"/> where T is <see cref="bool"/> to have <see langword="null"/> as default value and allowing global configuration usage.</summary>
+    /// <remarks>If <see langword="null"/> then use global configuration with <see langword="false"/> by default.</remarks>
+    /// <value><see langword="true"/> if headers hashing is enabled; otherwise, <see langword="false"/>.</value>
+    public bool? EnableHeadersHashing { get; set; }
+
+    /// <summary>Using <see cref="Nullable{T}"/> where T is <see cref="List{T}"/> to have <see langword="null"/> as default value and allowing global configuration usage.</summary>
+    /// <remarks>If <see langword="null"/> then use global configuration with empty list by default.</remarks>
+    /// <value>The list of regular expressions for cleanable hashing.</value>
+    public List<string>? CleanableHashingRegexes { get; set; }
 }

test/Ocelot.UnitTests/Cache/DefaultCacheKeyGeneratorTests.cs

@@ -35,7 +35,7 @@ public void should_generate_cache_key_with_request_content()
         const string noHeader = null;
         const string content = nameof(should_generate_cache_key_with_request_content);
         var cachekey = MD5Helper.GenerateMd5($"{verb}-{url}-{content}");
-        CacheOptions options = new CacheOptions(100, "region", noHeader, true);
+        CacheOptions options = new CacheOptions(100, "region", noHeader, true, false, null);
 
         this.Given(x => x.GivenDownstreamRoute(options))
             .And(x => GivenHasContent(content))
@@ -59,7 +59,7 @@ public void should_generate_cache_key_without_request_content()
     [Fact]
     public void should_generate_cache_key_with_cache_options_header()
     {
-        CacheOptions options = new CacheOptions(100, "region", headerName, false);
+        CacheOptions options = new CacheOptions(100, "region", headerName, false, false, null);
         var cachekey = MD5Helper.GenerateMd5($"{verb}-{url}-{header}");
 
         this.Given(x => x.GivenDownstreamRoute(options))
@@ -72,7 +72,7 @@ public void should_generate_cache_key_with_cache_options_header()
     public void should_generate_cache_key_happy_path()
     {
         const string content = nameof(should_generate_cache_key_happy_path);
-        CacheOptions options = new CacheOptions(100, "region", headerName, true);
+        CacheOptions options = new CacheOptions(100, "region", headerName, true, false, null);
         var cachekey = MD5Helper.GenerateMd5($"{verb}-{url}-{header}-{content}");
 
         this.Given(x => x.GivenDownstreamRoute(options))

test/Ocelot.UnitTests/Cache/OutputCacheMiddlewareTests.cs

@@ -106,7 +106,7 @@ private void GivenTheDownstreamRouteIs()
         var route = new RouteBuilder()
             .WithDownstreamRoute(new DownstreamRouteBuilder()
                 .WithIsCached(true)
-                .WithCacheOptions(new CacheOptions(100, "kanken", null, false))
+                .WithCacheOptions(new CacheOptions(100, "kanken", null, false, false, null))
                 .WithUpstreamHttpMethod(new List<string> { "Get" })
                 .Build())
             .WithUpstreamHttpMethod(new List<string> { "Get" })

test/Ocelot.UnitTests/CacheManager/OutputCacheMiddlewareRealCacheTests.cs

@@ -77,7 +77,7 @@ private void GivenTheDownstreamRouteIs()
     {
         var route = new DownstreamRouteBuilder()
             .WithIsCached(true)
-            .WithCacheOptions(new CacheOptions(100, "kanken", null, false))
+            .WithCacheOptions(new CacheOptions(100, "kanken", null, false, false, null))
             .WithUpstreamHttpMethod(new List<string> { "Get" })
             .Build();
 

test/Ocelot.UnitTests/Configuration/DownstreamRouteExtensionsTests.cs

@@ -29,7 +29,7 @@ public DownstreamRouteExtensionsTests()
             null,
             null,
             default,
-            new CacheOptions(0, null, null, null),
+            new CacheOptions(0, null, null, null, null, null),
             new LoadBalancerOptions(null, null, 0),
             new RateLimitOptions(false, null, null, false, null, null, null, 0),
             new Dictionary<string, string>(),

test/Ocelot.UnitTests/Configuration/RoutesCreatorTests.cs

@@ -181,7 +181,7 @@ private void GivenTheDependenciesAreSetUpCorrectly()
         _qoso = new QoSOptionsBuilder().Build();
         _rlo = new RateLimitOptionsBuilder().Build();
 
-        _cacheOptions = new CacheOptions(0, "vesty", null, false);
+        _cacheOptions = new CacheOptions(0, "vesty", null, false, false, null);
         _hho = new HttpHandlerOptionsBuilder().Build();
         _ht = new HeaderTransformations(new List<HeaderFindAndReplace>(), new List<HeaderFindAndReplace>(), new List<AddHeader>(), new List<AddHeader>());
         _dhp = new List<DownstreamHostAndPort>();