gzip filter: allow setting zlib compressor's chunk size

api/envoy/config/filter/http/gzip/v2/gzip.proto

@@ -20,7 +20,7 @@ option (udpa.annotations.file_status).package_version_status = ACTIVE;
 // Gzip :ref:`configuration overview <config_http_filters_gzip>`.
 // [#extension: envoy.filters.http.gzip]
 
-// [#next-free-field: 11]
+// [#next-free-field: 12]
 message Gzip {
   enum CompressionStrategy {
     DEFAULT = 0;
@@ -95,4 +95,8 @@ message Gzip {
   // the fields `content_length`, `content_type`, `disable_on_etag_header` and
   // `remove_accept_encoding_header` are ignored.
   compressor.v2.Compressor compressor = 10;
+
+  // Value for Zlib's next output buffer. If not set, defaults to 4096.
+  // See https://www.zlib.net/manual.html.
+  google.protobuf.UInt64Value chunk_size = 11 [(validate.rules).uint64 = {lte: 65536 gte: 4096}];
 }

api/envoy/extensions/filters/http/gzip/v3/gzip.proto

@@ -19,7 +19,7 @@ option (udpa.annotations.file_status).package_version_status = NEXT_MAJOR_VERSIO
 // Gzip :ref:`configuration overview <config_http_filters_gzip>`.
 // [#extension: envoy.filters.http.gzip]
 
-// [#next-free-field: 11]
+// [#next-free-field: 12]
 message Gzip {
   option (udpa.annotations.versioning).previous_message_type =
       "envoy.config.filter.http.gzip.v2.Gzip";
@@ -76,4 +76,8 @@ message Gzip {
   // the fields `content_length`, `content_type`, `disable_on_etag_header` and
   // `remove_accept_encoding_header` are ignored.
   compressor.v3.Compressor compressor = 10;
+
+  // Value for Zlib's next output buffer. If not set, defaults to 4096.
+  // See https://www.zlib.net/manual.html.
+  google.protobuf.UInt64Value chunk_size = 11 [(validate.rules).uint64 = {lte: 65536 gte: 4096}];
 }

docs/root/intro/version_history.rst

@@ -17,8 +17,6 @@ Version history
 * aws_request_signing: a few fixes so that it works with S3.
 * buffer: force copy when appending small slices to OwnedImpl buffer to avoid fragmentation.
 * config: use type URL to select an extension whenever the config type URL (or its previous versions) uniquely identify a typed extension, see :ref:`extension configuration <config_overview_extension_configuration>`.
-* grpc-json: added support for building HTTP request into
-  `google.api.HttpBody <https://github.com/googleapis/googleapis/blob/master/google/api/httpbody.proto>`_.
 * config: added stat :ref:`update_time <config_cluster_manager_cds>`.
 * datasource: added retry policy for remote async data source.
 * dns: the STRICT_DNS cluster now only resolves to 0 hosts if DNS resolution successfully returns 0 hosts.
@@ -28,6 +26,9 @@ Version history
 * ext_authz: disabled the use of lowercase string matcher for headers matching in HTTP-based `ext_authz`.
   Can be reverted temporarily by setting runtime feature `envoy.reloadable_features.ext_authz_http_service_enable_case_sensitive_string_matcher` to false.
 * fault: added support for controlling abort faults with :ref:`HTTP header fault configuration <config_http_filters_fault_injection_http_header>` to the HTTP fault filter.
+* grpc-json: added support for building HTTP request into
+  `google.api.HttpBody <https://github.com/googleapis/googleapis/blob/master/google/api/httpbody.proto>`_.
+* gzip filter: added option to set zlib's next output buffer.
 * http: added HTTP/1.1 flood protection. Can be temporarily disabled using the runtime feature `envoy.reloadable_features.http1_flood_protection`
 * http: fixing a bug in HTTP/1.0 responses where Connection: keep-alive was not appended for connections which were kept alive.
 * http: fixed a bug that could send extra METADATA frames and underflow memory when encoding METADATA frames on a connection that was dispatching data.

source/extensions/filters/http/gzip/gzip_filter.cc

@@ -28,10 +28,11 @@ GzipFilterConfig::GzipFilterConfig(const envoy::extensions::filters::http::gzip:
       compression_level_(compressionLevelEnum(gzip.compression_level())),
       compression_strategy_(compressionStrategyEnum(gzip.compression_strategy())),
       memory_level_(memoryLevelUint(gzip.memory_level().value())),
-      window_bits_(windowBitsUint(gzip.window_bits().value())) {}
+      window_bits_(windowBitsUint(gzip.window_bits().value())),
+      chunk_size_(gzip.chunk_size().value() > 0 ? gzip.chunk_size().value() : 4096) {}
 
 std::unique_ptr<Compressor::Compressor> GzipFilterConfig::makeCompressor() {
-  auto compressor = std::make_unique<Compressor::ZlibCompressorImpl>();
+  auto compressor = std::make_unique<Compressor::ZlibCompressorImpl>(chunk_size_);
   compressor->init(compressionLevel(), compressionStrategy(), windowBits(), memoryLevel());
   return compressor;
 }

source/extensions/filters/http/gzip/gzip_filter.h

@@ -31,6 +31,7 @@ class GzipFilterConfig : public Common::Compressors::CompressorFilterConfig {
 
   uint64_t memoryLevel() const { return memory_level_; }
   uint64_t windowBits() const { return window_bits_; }
+  uint64_t chunkSize() const { return chunk_size_; }
 
 private:
   static Compressor::ZlibCompressorImpl::CompressionLevel compressionLevelEnum(
@@ -48,8 +49,9 @@ class GzipFilterConfig : public Common::Compressors::CompressorFilterConfig {
   Compressor::ZlibCompressorImpl::CompressionLevel compression_level_;
   Compressor::ZlibCompressorImpl::CompressionStrategy compression_strategy_;
 
-  int32_t memory_level_;
-  int32_t window_bits_;
+  const int32_t memory_level_;
+  const int32_t window_bits_;
+  const uint64_t chunk_size_;
 };
 
 } // namespace Gzip

test/extensions/filters/http/gzip/gzip_filter_test.cc

@@ -417,6 +417,21 @@ TEST(GzipFilterConfigTest, DEPRECATED_FEATURE_TEST(DeprecatedExtensionFilterName
           deprecated_name));
 }
 
+// Test setting zlib's chunk size.
+TEST_F(GzipFilterTest, ChunkSize) {
+  // Default
+  setUpFilter("{}");
+  EXPECT_EQ(config_->chunkSize(), 4096);
+
+  // Override
+  setUpFilter(R"EOF(
+{
+  "chunk_size": 8192
+}
+)EOF");
+  EXPECT_EQ(config_->chunkSize(), 8192);
+}
+
 } // namespace Gzip
 } // namespace HttpFilters
 } // namespace Extensions