/*
 *
 * Copyright 2014 gRPC authors. 
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License. 
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
 * See the License for the specific language governing permissions and
 * limitations under the License. 
 *
 */

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

import (
	"context"
	"net"

	"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
}
