Fix ext_proc filter can not send non-utf8 character by gRPC (#27865)

* Fix ext_proc filter can not send non-utf8 character by gRPC

Signed-off-by: Yanjun Xiang <yanjunxiang@google.com>

Mirrored from https://github.com/envoyproxy/envoy @ 9c6e75062ebdd8c8382c671662fb096569d9eaa9

envoy/config/core/v3/base.proto

@@ -324,8 +324,18 @@ message HeaderValue {
   // The same :ref:`format specifier <config_access_log_format>` as used for
   // :ref:`HTTP access logging <config_access_log>` applies here, however
   // unknown header values are replaced with the empty string instead of ``-``.
+  // Header value is encoded as string. This does not work for non-utf8 characters.
+  // Only one of ``value`` or ``value_bytes`` can be set.
   string value = 2 [
-    (validate.rules).string = {max_bytes: 16384 well_known_regex: HTTP_HEADER_VALUE strict: false}
+    (validate.rules).string = {max_bytes: 16384 well_known_regex: HTTP_HEADER_VALUE strict: false},
+    (udpa.annotations.field_migrate).oneof_promotion = "value_type"
+  ];
+
+  // Header value is encoded as bytes which can support non-utf8 characters.
+  // Only one of ``value`` or ``value_bytes`` can be set.
+  bytes value_bytes = 3 [
+    (validate.rules).bytes = {min_len: 0 max_len: 16384},
+    (udpa.annotations.field_migrate).oneof_promotion = "value_type"
   ];
 }
 

envoy/service/ext_proc/v3/external_processor.proto

@@ -199,6 +199,12 @@ message ProcessingResponse {
 message HttpHeaders {
   // The HTTP request headers. All header keys will be
   // lower-cased, because HTTP header keys are case-insensitive.
+  // The ``headers`` encoding is based on the runtime guard
+  // envoy_reloadable_features_send_header_value_in_bytes setting.
+  // When it is true, the header value is encoded in the
+  // :ref:`value_bytes <envoy_v3_api_field_config.core.v3.HeaderValue.value_bytes>` field.
+  // When it is false, the header value is encoded in the
+  // :ref:`value <envoy_v3_api_field_config.core.v3.HeaderValue.value>` field.
   config.core.v3.HeaderMap headers = 1;
 
   // [#not-implemented-hide:]
@@ -223,6 +229,12 @@ message HttpBody {
 
 // This message contains the trailers.
 message HttpTrailers {
+  // The ``trailers`` encoding is based on the runtime guard
+  // envoy_reloadable_features_send_header_value_in_bytes setting.
+  // When it is true, the header value is encoded in the
+  // :ref:`value_bytes <envoy_v3_api_field_config.core.v3.HeaderValue.value_bytes>` field.
+  // When it is false, the header value is encoded in the
+  // :ref:`value <envoy_v3_api_field_config.core.v3.HeaderValue.value>` field.
   config.core.v3.HeaderMap trailers = 1;
 }
 
@@ -290,6 +302,12 @@ message CommonResponse {
   // Add new trailers to the message. This may be used when responding to either a
   // HttpHeaders or HttpBody message, but only if this message is returned
   // along with the CONTINUE_AND_REPLACE status.
+  // The ``trailers`` encoding is based on the runtime guard
+  // envoy_reloadable_features_send_header_value_in_bytes setting.
+  // When it is true, the header value is encoded in the
+  // :ref:`value_bytes <envoy_v3_api_field_config.core.v3.HeaderValue.value_bytes>` field.
+  // When it is false, the header value is encoded in the
+  // :ref:`value <envoy_v3_api_field_config.core.v3.HeaderValue.value>` field.
   config.core.v3.HeaderMap trailers = 4;
 
   // Clear the route cache for the current client request. This is necessary
@@ -337,6 +355,12 @@ message HeaderMutation {
   // Add or replace HTTP headers. Attempts to set the value of
   // any ``x-envoy`` header, and attempts to set the ``:method``,
   // ``:authority``, ``:scheme``, or ``host`` headers will be ignored.
+  // The ``set_headers`` encoding is based on the runtime guard
+  // envoy_reloadable_features_send_header_value_in_bytes setting.
+  // When it is true, the header value is encoded in the
+  // :ref:`value_bytes <envoy_v3_api_field_config.core.v3.HeaderValue.value_bytes>` field.
+  // When it is false, the header value is encoded in the
+  // :ref:`value <envoy_v3_api_field_config.core.v3.HeaderValue.value>` field.
   repeated config.core.v3.HeaderValueOption set_headers = 1;
 
   // Remove these HTTP headers. Attempts to remove system headers --