1/* 2 * 3 * Copyright 2017 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 keepalive defines configurable parameters for point-to-point healthcheck. 20package keepalive 21 22import ( 23 "time" 24) 25 26// ClientParameters is used to set keepalive parameters on the client-side. 27// These configure how the client will actively probe to notice when a connection is broken 28// and send pings so intermediaries will be aware of the liveness of the connection. 29// Make sure these parameters are set in coordination with the keepalive policy on the server, 30// as incompatible settings can result in closing of connection. 31type ClientParameters struct { 32 // After a duration of this time if the client doesn't see any activity it pings the server to see if the transport is still alive. 33 Time time.Duration // The current default value is infinity. 34 // After having pinged for keepalive check, the client waits for a duration of Timeout and if no activity is seen even after that 35 // the connection is closed. 36 Timeout time.Duration // The current default value is 20 seconds. 37 // If true, client runs keepalive checks even with no active RPCs. 38 PermitWithoutStream bool // false by default. 39} 40 41// ServerParameters is used to set keepalive and max-age parameters on the server-side. 42type ServerParameters struct { 43 // MaxConnectionIdle is a duration for the amount of time after which an idle connection would be closed by sending a GoAway. 44 // Idleness duration is defined since the most recent time the number of outstanding RPCs became zero or the connection establishment. 45 MaxConnectionIdle time.Duration // The current default value is infinity. 46 // MaxConnectionAge is a duration for the maximum amount of time a connection may exist before it will be closed by sending a GoAway. 47 // A random jitter of +/-10% will be added to MaxConnectionAge to spread out connection storms. 48 MaxConnectionAge time.Duration // The current default value is infinity. 49 // MaxConnectinoAgeGrace is an additive period after MaxConnectionAge after which the connection will be forcibly closed. 50 MaxConnectionAgeGrace time.Duration // The current default value is infinity. 51 // After a duration of this time if the server doesn't see any activity it pings the client to see if the transport is still alive. 52 Time time.Duration // The current default value is 2 hours. 53 // After having pinged for keepalive check, the server waits for a duration of Timeout and if no activity is seen even after that 54 // the connection is closed. 55 Timeout time.Duration // The current default value is 20 seconds. 56} 57 58// EnforcementPolicy is used to set keepalive enforcement policy on the server-side. 59// Server will close connection with a client that violates this policy. 60type EnforcementPolicy struct { 61 // MinTime is the minimum amount of time a client should wait before sending a keepalive ping. 62 MinTime time.Duration // The current default value is 5 minutes. 63 // If true, server expects keepalive pings even when there are no active streams(RPCs). 64 PermitWithoutStream bool // false by default. 65} 66