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diff --git a/include/grpcpp/impl/codegen/interceptor.h b/include/grpcpp/impl/codegen/interceptor.h
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+++ b/include/grpcpp/impl/codegen/interceptor.h
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+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * 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.
+ *
+ */
+
+#ifndef GRPCPP_IMPL_CODEGEN_INTERCEPTOR_H
+#define GRPCPP_IMPL_CODEGEN_INTERCEPTOR_H
+
+#include <grpc/impl/codegen/grpc_types.h>
+#include <grpcpp/impl/codegen/byte_buffer.h>
+#include <grpcpp/impl/codegen/config.h>
+#include <grpcpp/impl/codegen/core_codegen_interface.h>
+#include <grpcpp/impl/codegen/metadata_map.h>
+
+namespace grpc {
+
+class ChannelInterface;
+class Status;
+
+namespace experimental {
+class InterceptedMessage {
+ public:
+  template <class M>
+  bool Extract(M* msg);  // returns false if definitely invalid extraction
+  template <class M>
+  M* MutableExtract();
+  uint64_t length();  // length on wire
+};
+
+enum class InterceptionHookPoints {
+  /* The first two in this list are for clients and servers */
+  PRE_SEND_INITIAL_METADATA,
+  PRE_SEND_MESSAGE,
+  PRE_SEND_STATUS /* server only */,
+  PRE_SEND_CLOSE /* client only */,
+  /* The following three are for hijacked clients only and can only be
+     registered by the global interceptor */
+  PRE_RECV_INITIAL_METADATA,
+  PRE_RECV_MESSAGE,
+  PRE_RECV_STATUS,
+  /* The following two are for all clients and servers */
+  POST_RECV_INITIAL_METADATA,
+  POST_RECV_MESSAGE,
+  POST_RECV_STATUS /* client only */,
+  POST_RECV_CLOSE /* server only */,
+  /* This is a special hook point available to both clients and servers when
+     TryCancel() is performed.
+     - No other hook points will be present along with this.
+     - It is illegal for an interceptor to block/delay this operation.
+     - ALL interceptors see this hook point irrespective of whether the RPC was
+     hijacked or not. */
+  PRE_SEND_CANCEL,
+  NUM_INTERCEPTION_HOOKS
+};
+
+class InterceptorBatchMethods {
+ public:
+  virtual ~InterceptorBatchMethods(){};
+  // Queries to check whether the current batch has an interception hook point
+  // of type \a type
+  virtual bool QueryInterceptionHookPoint(InterceptionHookPoints type) = 0;
+  // Calling this will signal that the interceptor is done intercepting the
+  // current batch of the RPC.
+  // Proceed is a no-op if the batch contains PRE_SEND_CANCEL. Simply returning
+  // from the Intercept method does the job of continuing the RPC in this case.
+  virtual void Proceed() = 0;
+  // Calling this indicates that the interceptor has hijacked the RPC (only
+  // valid if the batch contains send_initial_metadata on the client side)
+  virtual void Hijack() = 0;
+
+  // Returns a modifable ByteBuffer holding serialized form of the message to be
+  // sent
+  virtual ByteBuffer* GetSendMessage() = 0;
+
+  // Returns a modifiable multimap of the initial metadata to be sent
+  virtual std::multimap<grpc::string, grpc::string>*
+  GetSendInitialMetadata() = 0;
+
+  // Returns the status to be sent
+  virtual Status GetSendStatus() = 0;
+
+  // Modifies the status with \a status
+  virtual void ModifySendStatus(const Status& status) = 0;
+
+  // Returns a modifiable multimap of the trailing metadata to be sent
+  virtual std::multimap<grpc::string, grpc::string>*
+  GetSendTrailingMetadata() = 0;
+
+  // Returns a pointer to the modifiable received message. Note that the message
+  // is already deserialized
+  virtual void* GetRecvMessage() = 0;
+
+  // Returns a modifiable multimap of the received initial metadata
+  virtual std::multimap<grpc::string_ref, grpc::string_ref>*
+  GetRecvInitialMetadata() = 0;
+
+  // Returns a modifiable view of the received status
+  virtual Status* GetRecvStatus() = 0;
+
+  // Returns a modifiable multimap of the received trailing metadata
+  virtual std::multimap<grpc::string_ref, grpc::string_ref>*
+  GetRecvTrailingMetadata() = 0;
+
+  // Gets an intercepted channel. When a call is started on this interceptor,
+  // only interceptors after the current interceptor are created from the
+  // factory objects registered with the channel.
+  virtual std::unique_ptr<ChannelInterface> GetInterceptedChannel() = 0;
+};
+
+class Interceptor {
+ public:
+  virtual ~Interceptor() {}
+
+  virtual void Intercept(InterceptorBatchMethods* methods) = 0;
+};
+
+}  // namespace experimental
+}  // namespace grpc
+
+#endif  // GRPCPP_IMPL_CODEGEN_INTERCEPTOR_H