grpc-json-transcoder: Add support for configuring unescaping behavior

api/envoy/extensions/filters/http/grpc_json_transcoder/v3/transcoder.proto

@@ -15,11 +15,27 @@ option (udpa.annotations.file_status).package_version_status = ACTIVE;
 // gRPC-JSON transcoder :ref:`configuration overview <config_http_filters_grpc_json_transcoder>`.
 // [#extension: envoy.filters.http.grpc_json_transcoder]
 
-// [#next-free-field: 10]
+// [#next-free-field: 11]
 message GrpcJsonTranscoder {
   option (udpa.annotations.versioning).previous_message_type =
       "envoy.config.filter.http.transcoder.v2.GrpcJsonTranscoder";
 
+  enum UrlUnescapeSpec {
+    // URL path parameters will not decode RFC 6570 reserved characters.
+    // For example, segment `%2f%23/%20%2523` is unescaped to `%2f%23/ %23`.
+    ALL_CHARACTERS_EXCEPT_RESERVED = 0;
+
+    // URL path parameters will be fully URI-decoded except in
+    // cases of single segment matches in reserved expansion, where "%2F" will be
+    // left encoded.
+    // For example, segment `%2f%23/%20%2523` is unescaped to `%2f#/ %23`.
+    ALL_CHARACTERS_EXCEPT_SLASH = 1;
+
+    // URL path parameters will be fully URI-decoded.
+    // For example, segment `%2f%23/%20%2523` is unescaped to `/#/ %23`.
+    ALL_CHARACTERS = 2;
+  }
+
   message PrintOptions {
     option (udpa.annotations.versioning).previous_message_type =
         "envoy.config.filter.http.transcoder.v2.GrpcJsonTranscoder.PrintOptions";
@@ -160,4 +176,11 @@ message GrpcJsonTranscoder {
   //  the ``google/rpc/error_details.proto`` should be included in the configured
   //  :ref:`proto descriptor set <config_grpc_json_generate_proto_descriptor_set>`.
   bool convert_grpc_status = 9;
+
+  // URL unescaping policy.
+  // This spec is only applied when extracting variable with multiple segments.
+  // For example, in case of `/foo/{x=*}/bar/{y=prefix/*}/{z=**}` `x` variable is single segment and `y` and `z` are multiple segments.
+  // For a path with `/foo/first/bar/prefix/second/third/fourth`, `x=first`, `y=prefix/second`, `z=third/fourth`.
+  // If this setting is not specified, the value defaults to :ref:`ALL_CHARACTERS_EXCEPT_RESERVED<envoy_api_enum_value_extensions.filters.http.grpc_json_transcoder.v3.GrpcJsonTranscoder.UrlUnescapeSpec.ALL_CHARACTERS_EXCEPT_RESERVED>`.
+  UrlUnescapeSpec url_unescape_spec = 10 [(validate.rules).enum = {defined_only: true}];
 }

bazel/repository_locations.bzl

@@ -507,13 +507,13 @@ REPOSITORY_LOCATIONS_SPEC = dict(
         project_name = "grpc-httpjson-transcoding",
         project_desc = "Library that supports transcoding so that HTTP/JSON can be converted to gRPC",
         project_url = "https://github.com/grpc-ecosystem/grpc-httpjson-transcoding",
-        version = "b48d8aa15b3825e146168146755475ab918e95b7",
-        sha256 = "4147e992ec239fb78c435fdd9f68e8d93d89106f67278bf2995f3672dddba52b",
+        version = "4d095f048889d4fc3b8d4579aa80ca4290319802",
+        sha256 = "7af66e0674340932683ab4f04ea6f03e2550849a54741738d94310b84d396a2c",
         strip_prefix = "grpc-httpjson-transcoding-{version}",
         urls = ["https://github.com/grpc-ecosystem/grpc-httpjson-transcoding/archive/{version}.tar.gz"],
         use_category = ["dataplane_ext"],
         extensions = ["envoy.filters.http.grpc_json_transcoder"],
-        release_date = "2020-11-05",
+        release_date = "2020-11-12",
         cpe = "N/A",
     ),
     io_bazel_rules_go = dict(

docs/root/version_history/current.rst

@@ -50,6 +50,7 @@ New Features
 ------------
 * config: added new runtime feature `envoy.features.enable_all_deprecated_features` that allows the use of all deprecated features.
 * grpc: implemented header value syntax support when defining :ref:`initial metadata <envoy_v3_api_field_config.core.v3.GrpcService.initial_metadata>` for gRPC-based `ext_authz` :ref:`HTTP <envoy_v3_api_field_extensions.filters.http.ext_authz.v3.ExtAuthz.grpc_service>` and :ref:`network <envoy_v3_api_field_extensions.filters.network.ext_authz.v3.ExtAuthz.grpc_service>` filters, and :ref:`ratelimit <envoy_v3_api_field_config.ratelimit.v3.RateLimitServiceConfig.grpc_service>` filters.
+* grpc-json: added support for configuring :ref:`unescaping behavior <envoy_v3_api_field_extensions.filters.http.grpc_json_transcoder.v3.GrpcJsonTranscoder.url_unescape_spec>` for path components.
 * hds: added support for delta updates in the :ref:`HealthCheckSpecifier <envoy_v3_api_msg_service.health.v3.HealthCheckSpecifier>`, making only the Endpoints and Health Checkers that changed be reconstructed on receiving a new message, rather than the entire HDS.
 * health_check: added option to use :ref:`no_traffic_healthy_interval <envoy_v3_api_field_config.core.v3.HealthCheck.no_traffic_healthy_interval>` which allows a different no traffic interval when the host is healthy.
 * http: added HCM :ref:`timeout config field <envoy_v3_api_field_extensions.filters.network.http_connection_manager.v3.HttpConnectionManager.request_headers_timeout>` to control how long a downstream has to finish sending headers before the stream is cancelled.

source/extensions/filters/http/grpc_json_transcoder/json_transcoder_filter.cc

@@ -188,6 +188,24 @@ JsonTranscoderConfig::JsonTranscoderConfig(
     }
   }
 
+  switch (proto_config.url_unescape_spec()) {
+  case envoy::extensions::filters::http::grpc_json_transcoder::v3::GrpcJsonTranscoder::
+      ALL_CHARACTERS_EXCEPT_RESERVED:
+    pmb.SetUrlUnescapeSpec(
+        google::grpc::transcoding::UrlUnescapeSpec::kAllCharactersExceptReserved);
+    break;
+  case envoy::extensions::filters::http::grpc_json_transcoder::v3::GrpcJsonTranscoder::
+      ALL_CHARACTERS_EXCEPT_SLASH:
+    pmb.SetUrlUnescapeSpec(google::grpc::transcoding::UrlUnescapeSpec::kAllCharactersExceptSlash);
+    break;
+  case envoy::extensions::filters::http::grpc_json_transcoder::v3::GrpcJsonTranscoder::
+      ALL_CHARACTERS:
+    pmb.SetUrlUnescapeSpec(google::grpc::transcoding::UrlUnescapeSpec::kAllCharacters);
+    break;
+  default:
+    NOT_REACHED_GCOVR_EXCL_LINE;
+  }
+
   path_matcher_ = pmb.Build();
 
   const auto& print_config = proto_config.print_options();

test/extensions/filters/http/grpc_json_transcoder/json_transcoder_filter_test.cc

@@ -1270,6 +1270,78 @@ INSTANTIATE_TEST_SUITE_P(
     })",
             R"({"id":"101","gender":"MALE","last_name":"Shakespeare"})"}));
 
+struct GrpcJsonTranscoderFilterUnescapeTestParam {
+  std::string config_json_;
+  std::string expected_arg_;
+};
+
+class GrpcJsonTranscoderFilterUnescapeTest
+    : public testing::TestWithParam<GrpcJsonTranscoderFilterUnescapeTestParam>,
+      public GrpcJsonTranscoderFilterTestBase {
+protected:
+  GrpcJsonTranscoderFilterUnescapeTest() {
+    envoy::extensions::filters::http::grpc_json_transcoder::v3::GrpcJsonTranscoder proto_config;
+    TestUtility::loadFromJson(TestEnvironment::substitute(GetParam().config_json_), proto_config);
+    config_ = std::make_unique<JsonTranscoderConfig>(proto_config, *api_);
+    filter_ = std::make_unique<JsonTranscoderFilter>(*config_);
+    filter_->setDecoderFilterCallbacks(decoder_callbacks_);
+    filter_->setEncoderFilterCallbacks(encoder_callbacks_);
+  }
+
+  std::unique_ptr<JsonTranscoderConfig> config_;
+  std::unique_ptr<JsonTranscoderFilter> filter_;
+  NiceMock<Http::MockStreamDecoderFilterCallbacks> decoder_callbacks_;
+  NiceMock<Http::MockStreamEncoderFilterCallbacks> encoder_callbacks_;
+};
+
+TEST_P(GrpcJsonTranscoderFilterUnescapeTest, UnescapeSpec) {
+  Http::TestRequestHeaderMapImpl request_headers{
+      {"content-type", "text/plain"}, {":method", "POST"}, {":path", "/wildcard/%2f%23/%20%2523"}};
+  EXPECT_EQ(Http::FilterHeadersStatus::Continue, filter_->decodeHeaders(request_headers, false));
+
+  Buffer::OwnedImpl request_data{"{}"};
+  EXPECT_EQ(Http::FilterDataStatus::Continue, filter_->decodeData(request_data, true));
+
+  Grpc::Decoder decoder;
+  std::vector<Grpc::Frame> frames;
+  decoder.decode(request_data, frames);
+
+  EXPECT_EQ(1, frames.size());
+
+  bookstore::EchoBodyRequest expected_request;
+  expected_request.set_arg(GetParam().expected_arg_);
+
+  bookstore::EchoBodyRequest request;
+  request.ParseFromString(frames[0].data_->toString());
+
+  EXPECT_EQ(expected_request.ByteSize(), frames[0].length_);
+  EXPECT_TRUE(MessageDifferencer::Equals(expected_request, request));
+}
+
+INSTANTIATE_TEST_SUITE_P(GrpcJsonTranscoderFilterUnescapeOptions,
+                         GrpcJsonTranscoderFilterUnescapeTest,
+                         ::testing::Values(
+                             GrpcJsonTranscoderFilterUnescapeTestParam{
+                                 R"({
+     "proto_descriptor": "{{ test_rundir }}/test/proto/bookstore.descriptor",
+     "services": ["bookstore.Bookstore"]
+    })",
+                                 "%2f%23/ %23"},
+                             GrpcJsonTranscoderFilterUnescapeTestParam{
+                                 R"({
+     "proto_descriptor": "{{ test_rundir }}/test/proto/bookstore.descriptor",
+     "services": ["bookstore.Bookstore"],
+     "url_unescape_spec": "ALL_CHARACTERS_EXCEPT_SLASH"
+    })",
+                                 "%2f#/ %23"},
+                             GrpcJsonTranscoderFilterUnescapeTestParam{
+                                 R"({
+     "proto_descriptor": "{{ test_rundir }}/test/proto/bookstore.descriptor",
+     "services": ["bookstore.Bookstore"],
+     "url_unescape_spec": "ALL_CHARACTERS"
+    })",
+                                 "/#/ %23"}));
+
 } // namespace
 } // namespace GrpcJsonTranscoder
 } // namespace HttpFilters

test/proto/bookstore.proto

@@ -134,6 +134,11 @@ service Bookstore {
       get: "/bigbook"
     };
   }
+  rpc PostWildcard(EchoBodyRequest) returns (google.protobuf.Empty) {
+    option (google.api.http) = {
+      post: "/wildcard/{arg=**}"
+    };
+  }
 }
 
 service ServiceWithResponseBody {