peer.go

/*
 *
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// Package peer defines various peer information associated with RPCs and
// corresponding utils.
package peer

import (
	"net"

	"golang.org/x/net/context"
	"google.golang.org/grpc/credentials"
)

// Peer contains the information of the peer for an RPC, such as the address
// and authentication information.
type Peer struct {
	// Addr is the peer address.
	Addr net.Addr
	// AuthInfo is the authentication information of the transport.
	// It is nil if there is no transport security being used.
	AuthInfo credentials.AuthInfo
}

type peerKey struct{}

// NewContext creates a new context with peer information attached.
func NewContext(ctx context.Context, p *Peer) context.Context {
	return context.WithValue(ctx, peerKey{}, p)
}

// FromContext returns the peer information in ctx if it exists.
func FromContext(ctx context.Context) (p *Peer, ok bool) {
	p, ok = ctx.Value(peerKey{}).(*Peer)
	return
}