middleware

type MetricRole int

type MetricsObserver interface {
	OnUnaryRequest(role MetricRole, rpcInfo psrpc.RPCInfo, duration time.Duration, err error)
	OnMultiRequest(role MetricRole, rpcInfo psrpc.RPCInfo, duration time.Duration, responseCount int, errorCount int)
	OnStreamSend(role MetricRole, rpcInfo psrpc.RPCInfo, duration time.Duration, err error)
	OnStreamRecv(role MetricRole, rpcInfo psrpc.RPCInfo, err error)
	OnStreamOpen(role MetricRole, rpcInfo psrpc.RPCInfo)
	OnStreamClose(role MetricRole, rpcInfo psrpc.RPCInfo)
}

type RetryOptions struct {
	MaxAttempts   int
	Timeout       time.Duration
	Backoff       time.Duration
	IsRecoverable func(err error) bool
}