1 /* 2 * Copyright 2014 The gRPC Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package io.grpc.internal; 18 19 import io.grpc.Metadata; 20 import io.grpc.Status; 21 22 /** An observer of client-side stream events. */ 23 public interface ClientStreamListener extends StreamListener { 24 /** 25 * Called upon receiving all header information from the remote end-point. Note that transports 26 * are not required to call this method if no header information is received, this would occur 27 * when a stream immediately terminates with an error and only 28 * {@link #closed(io.grpc.Status, Metadata)} is called. 29 * 30 * <p>This method should return quickly, as the same thread may be used to process other streams. 31 * 32 * @param headers the fully buffered received headers. 33 */ headersRead(Metadata headers)34 void headersRead(Metadata headers); 35 36 /** 37 * Called when the stream is fully closed. {@link 38 * io.grpc.Status.Code#OK} is the only status code that is guaranteed 39 * to have been sent from the remote server. Any other status code may have been caused by 40 * abnormal stream termination. This is guaranteed to always be the final call on a listener. No 41 * further callbacks will be issued. 42 * 43 * <p>This method should return quickly, as the same thread may be used to process other streams. 44 * 45 * @param status details about the remote closure 46 * @param trailers trailing metadata 47 */ 48 // TODO(zdapeng): remove this method in favor of the 3-arg one. closed(Status status, Metadata trailers)49 void closed(Status status, Metadata trailers); 50 51 /** 52 * Called when the stream is fully closed. {@link 53 * io.grpc.Status.Code#OK} is the only status code that is guaranteed 54 * to have been sent from the remote server. Any other status code may have been caused by 55 * abnormal stream termination. This is guaranteed to always be the final call on a listener. No 56 * further callbacks will be issued. 57 * 58 * <p>This method should return quickly, as the same thread may be used to process other streams. 59 * 60 * @param status details about the remote closure 61 * @param rpcProgress RPC progress when client stream listener is closed 62 * @param trailers trailing metadata 63 */ closed(Status status, RpcProgress rpcProgress, Metadata trailers)64 void closed(Status status, RpcProgress rpcProgress, Metadata trailers); 65 66 /** 67 * The progress of the RPC when client stream listener is closed. 68 */ 69 enum RpcProgress { 70 /** 71 * The RPC is processed by the server normally. 72 */ 73 PROCESSED, 74 /** 75 * The RPC is not processed by the server's application logic. 76 */ 77 REFUSED, 78 /** 79 * The RPC is dropped (by load balancer). 80 */ 81 DROPPED 82 } 83 } 84