grpc-json-transcoder: support root path

bazel/repository_locations.bzl

@@ -505,8 +505,8 @@ 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 = "4d095f048889d4fc3b8d4579aa80ca4290319802",
-        sha256 = "7af66e0674340932683ab4f04ea6f03e2550849a54741738d94310b84d396a2c",
+        version = "22160afc7e67b9becce3198f8a6a321f01a3cef8",
+        sha256 = "d761b6442f600b628f5e420b601824757dfdbea6c12ac86cd59dbaa53d20d343",
         strip_prefix = "grpc-httpjson-transcoding-{version}",
         urls = ["https://github.com/grpc-ecosystem/grpc-httpjson-transcoding/archive/{version}.tar.gz"],
         use_category = ["dataplane_ext"],

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

@@ -733,6 +733,42 @@ TEST_F(GrpcJsonTranscoderFilterTest, TranscodingUnaryWithHttpBodyAsOutput) {
   EXPECT_EQ(Http::FilterTrailersStatus::Continue, filter_.decodeTrailers(request_trailers));
 }
 
+
+TEST_F(GrpcJsonTranscoderFilterTest, TranscodingUnaryOnRootPath) {
+  Http::TestRequestHeaderMapImpl request_headers{{":method", "GET"}, {":path", "/"}};
+
+  EXPECT_CALL(decoder_callbacks_, clearRouteCache());
+
+  EXPECT_EQ(Http::FilterHeadersStatus::Continue, filter_.decodeHeaders(request_headers, false));
+  EXPECT_EQ("application/grpc", request_headers.get_("content-type"));
+  EXPECT_EQ("/", request_headers.get_("x-envoy-original-path"));
+  EXPECT_EQ("GET", request_headers.get_("x-envoy-original-method"));
+  EXPECT_EQ("/bookstore.Bookstore/GetRoot", request_headers.get_(":path"));
+  EXPECT_EQ("trailers", request_headers.get_("te"));
+
+  Http::TestResponseHeaderMapImpl response_headers{{"content-type", "application/grpc"},
+                                                   {":status", "200"}};
+
+  EXPECT_EQ(Http::FilterHeadersStatus::StopIteration,
+            filter_.encodeHeaders(response_headers, false));
+  EXPECT_EQ("application/json", response_headers.get_("content-type"));
+
+  google::api::HttpBody response;
+  response.set_content_type("text/html");
+  response.set_data("<h1>Hello, world!</h1>");
+
+  auto response_data = Grpc::Common::serializeToGrpcFrame(response);
+
+  EXPECT_EQ(Http::FilterDataStatus::StopIterationAndBuffer,
+            filter_.encodeData(*response_data, false));
+
+  EXPECT_EQ(response.content_type(), response_headers.get_("content-type"));
+  EXPECT_EQ(response.data(), response_data->toString());
+
+  Http::TestRequestTrailerMapImpl request_trailers;
+  EXPECT_EQ(Http::FilterTrailersStatus::Continue, filter_.decodeTrailers(request_trailers));
+}
+
 TEST_F(GrpcJsonTranscoderFilterTest, TranscodingUnaryWithInvalidHttpBodyAsOutput) {
   Http::TestRequestHeaderMapImpl request_headers{{":method", "GET"},
                                                  {":path", "/echoResponseBodyPath"}};

test/proto/bookstore.proto

@@ -96,6 +96,11 @@ service Bookstore {
       get: "/indexStream"
     };
   }
+  rpc GetRoot(google.protobuf.Empty) returns (google.api.HttpBody) {
+    option (google.api.http) = {
+      get: "/"
+    };
+  }
   rpc PostBody(EchoBodyRequest) returns (google.protobuf.Empty) {
     option (google.api.http) = {
       post: "/postBody"