From 9ae3eaaeb014621f98b0ba48e7c5a13e587c2f1f Mon Sep 17 00:00:00 2001
From: Matt Joiner <anacrolix@gmail.com>
Date: Mon, 8 Apr 2019 18:11:34 +1000
Subject: [PATCH] Add to comment on KeyBook.PrivKey (#64)

---
 interface.go | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/interface.go b/interface.go
index 4d16668..bdf8839 100644
--- a/interface.go
+++ b/interface.go
@@ -125,14 +125,15 @@ type AddrBook interface {
 
 // KeyBook tracks the keys of Peers.
 type KeyBook interface {
-
 	// PubKey stores the public key of a peer.
 	PubKey(peer.ID) ic.PubKey
 
 	// AddPubKey stores the public key of a peer.
 	AddPubKey(peer.ID, ic.PubKey) error
 
-	// PrivKey returns the private key of a peer.
+	// PrivKey returns the private key of a peer, if known. Generally this might only be our own
+	// private key, see
+	// https://discuss.libp2p.io/t/what-is-the-purpose-of-having-map-peer-id-privatekey-in-peerstore/74.
 	PrivKey(peer.ID) ic.PrivKey
 
 	// AddPrivKey stores the private key of a peer.