1 /* 2 * 3 * Copyright 2016 gRPC authors. 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 * 17 */ 18 19 package grpc 20 21 import ( 22 "golang.org/x/net/context" 23 ) 24 25 // UnaryInvoker is called by UnaryClientInterceptor to complete RPCs. 26 type UnaryInvoker func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, opts ...CallOption) error 27 28 // UnaryClientInterceptor intercepts the execution of a unary RPC on the client. invoker is the handler to complete the RPC 29 // and it is the responsibility of the interceptor to call it. 30 // This is an EXPERIMENTAL API. 31 type UnaryClientInterceptor func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, invoker UnaryInvoker, opts ...CallOption) error 32 33 // Streamer is called by StreamClientInterceptor to create a ClientStream. 34 type Streamer func(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (ClientStream, error) 35 36 // StreamClientInterceptor intercepts the creation of ClientStream. It may return a custom ClientStream to intercept all I/O 37 // operations. streamer is the handler to create a ClientStream and it is the responsibility of the interceptor to call it. 38 // This is an EXPERIMENTAL API. 39 type StreamClientInterceptor func(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, streamer Streamer, opts ...CallOption) (ClientStream, error) 40 41 // UnaryServerInfo consists of various information about a unary RPC on 42 // server side. All per-rpc information may be mutated by the interceptor. 43 type UnaryServerInfo struct { 44 // Server is the service implementation the user provides. This is read-only. 45 Server interface{} 46 // FullMethod is the full RPC method string, i.e., /package.service/method. 47 FullMethod string 48 } 49 50 // UnaryHandler defines the handler invoked by UnaryServerInterceptor to complete the normal 51 // execution of a unary RPC. If a UnaryHandler returns an error, it should be produced by the 52 // status package, or else gRPC will use codes.Unknown as the status code and err.Error() as 53 // the status message of the RPC. 54 type UnaryHandler func(ctx context.Context, req interface{}) (interface{}, error) 55 56 // UnaryServerInterceptor provides a hook to intercept the execution of a unary RPC on the server. info 57 // contains all the information of this RPC the interceptor can operate on. And handler is the wrapper 58 // of the service method implementation. It is the responsibility of the interceptor to invoke handler 59 // to complete the RPC. 60 type UnaryServerInterceptor func(ctx context.Context, req interface{}, info *UnaryServerInfo, handler UnaryHandler) (resp interface{}, err error) 61 62 // StreamServerInfo consists of various information about a streaming RPC on 63 // server side. All per-rpc information may be mutated by the interceptor. 64 type StreamServerInfo struct { 65 // FullMethod is the full RPC method string, i.e., /package.service/method. 66 FullMethod string 67 // IsClientStream indicates whether the RPC is a client streaming RPC. 68 IsClientStream bool 69 // IsServerStream indicates whether the RPC is a server streaming RPC. 70 IsServerStream bool 71 } 72 73 // StreamServerInterceptor provides a hook to intercept the execution of a streaming RPC on the server. 74 // info contains all the information of this RPC the interceptor can operate on. And handler is the 75 // service method implementation. It is the responsibility of the interceptor to invoke handler to 76 // complete the RPC. 77 type StreamServerInterceptor func(srv interface{}, ss ServerStream, info *StreamServerInfo, handler StreamHandler) error 78