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+// Copyright 2018 Google LLC.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+syntax = "proto3";
+
+package google.api;
+
+option go_package = "google.golang.org/genproto/googleapis/api/serviceconfig;serviceconfig";
+option java_multiple_files = true;
+option java_outer_classname = "ContextProto";
+option java_package = "com.google.api";
+option objc_class_prefix = "GAPI";
+
+// `Context` defines which contexts an API requests.
+//
+// Example:
+//
+// context:
+// rules:
+// - selector: "*"
+// requested:
+// - google.rpc.context.ProjectContext
+// - google.rpc.context.OriginContext
+//
+// The above specifies that all methods in the API request
+// `google.rpc.context.ProjectContext` and
+// `google.rpc.context.OriginContext`.
+//
+// Available context types are defined in package
+// `google.rpc.context`.
+//
+// This also provides mechanism to whitelist any protobuf message extension that
+// can be sent in grpc metadata using “x-goog-ext-<extension_id>-bin” and
+// “x-goog-ext-<extension_id>-jspb” format. For example, list any service
+// specific protobuf types that can appear in grpc metadata as follows in your
+// yaml file:
+//
+// Example:
+//
+// context:
+// rules:
+// - selector: "google.example.library.v1.LibraryService.CreateBook"
+// allowed_request_extensions:
+// - google.foo.v1.NewExtension
+// allowed_response_extensions:
+// - google.foo.v1.NewExtension
+//
+// You can also specify extension ID instead of fully qualified extension name
+// here.
+message Context {
+ // A list of RPC context rules that apply to individual API methods.
+ //
+ // **NOTE:** All service configuration rules follow "last one wins" order.
+ repeated ContextRule rules = 1;
+}
+
+// A context rule provides information about the context for an individual API
+// element.
+message ContextRule {
+ // Selects the methods to which this rule applies.
+ //
+ // Refer to [selector][google.api.DocumentationRule.selector] for syntax
+ // details.
+ string selector = 1;
+
+ // A list of full type names of requested contexts.
+ repeated string requested = 2;
+
+ // A list of full type names of provided contexts.
+ repeated string provided = 3;
+
+ // A list of full type names or extension IDs of extensions allowed in grpc
+ // side channel from client to backend.
+ repeated string allowed_request_extensions = 4;
+
+ // A list of full type names or extension IDs of extensions allowed in grpc
+ // side channel from backend to client.
+ repeated string allowed_response_extensions = 5;
+}