keepalive

Documentation

Overview

Package keepalive defines configurable parameters for point-to-point healthcheck.

Index

• type ClientParameters
• type EnforcementPolicy
• type ServerParameters

Types

type ClientParameters

type ClientParameters struct {
	// 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.
	// If set below 10s, a minimum value of 10s will be used instead.
	//
	// Note that gRPC servers have a default EnforcementPolicy.MinTime of 5
	// minutes (which means the client shouldn't ping more frequently than every
	// 5 minutes).
	//
	// Though not ideal, it's not a strong requirement for Time to be less than
	// EnforcementPolicy.MinTime.  Time will automatically double if the server
	// disconnects due to its enforcement policy.
	//
	// For more details, see
	// https://github.com/grpc/proposal/blob/master/A8-client-side-keepalive.md
	Time time.Duration
	// After having pinged for keepalive check, the client waits for a duration
	// of Timeout and if no activity is seen even after that the connection is
	// closed.
	//
	// If keepalive is enabled, and this value is not explicitly set, the default
	// is 20 seconds.
	Timeout time.Duration
	// If true, client sends keepalive pings even with no active RPCs. If false,
	// when there are no active RPCs, Time and Timeout will be ignored and no
	// keepalive pings will be sent.
	PermitWithoutStream bool
}

ClientParameters is used to set keepalive parameters on the client-side. These configure how the client will actively probe to notice when a connection is broken and send pings so intermediaries will be aware of the liveness of the connection. Make sure these parameters are set in coordination with the keepalive policy on the server, as incompatible settings can result in closing of connection.

type EnforcementPolicy

type EnforcementPolicy struct {
	// MinTime is the minimum amount of time a client should wait before sending
	// a keepalive ping.
	MinTime time.Duration // The current default value is 5 minutes.
	// If true, server allows keepalive pings even when there are no active
	// streams(RPCs). If false, and client sends ping when there are no active
	// streams, server will send GOAWAY and close the connection.
	PermitWithoutStream bool // false by default.
}

EnforcementPolicy is used to set keepalive enforcement policy on the server-side. Server will close connection with a client that violates this policy.

type ServerParameters

type ServerParameters struct {
	// MaxConnectionIdle is a duration for the amount of time after which an
	// idle connection would be closed by sending a GoAway. Idleness duration is
	// defined since the most recent time the number of outstanding RPCs became
	// zero or the connection establishment.
	MaxConnectionIdle time.Duration // The current default value is infinity.
	// MaxConnectionAge is a duration for the maximum amount of time a
	// connection may exist before it will be closed by sending a GoAway. A
	// random jitter of +/-10% will be added to MaxConnectionAge to spread out
	// connection storms.
	MaxConnectionAge time.Duration // The current default value is infinity.
	// MaxConnectionAgeGrace is an additive period after MaxConnectionAge after
	// which the connection will be forcibly closed.
	MaxConnectionAgeGrace time.Duration // The current default value is infinity.
	// 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.
	// If set below 1s, a minimum value of 1s will be used instead.
	Time time.Duration // The current default value is 2 hours.
	// After having pinged for keepalive check, the server waits for a duration
	// of Timeout and if no activity is seen even after that the connection is
	// closed.
	Timeout time.Duration // The current default value is 20 seconds.
}

ServerParameters is used to set keepalive and max-age parameters on the server-side.