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 *
 * Copyright 2014, Google Inc.
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 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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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.
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
}