feat: add explicit error for case peer id not included in multiaddr (#155)

Author: chrisdostert

README.md

@@ -162,7 +162,7 @@ class Node extends libp2p {
 
 > Dials to another peer in the network.
 
-- `peer`: can be an instance of [PeerInfo][], [PeerId][] or [multiaddr][]
+- `peer`: can be an instance of [PeerInfo][], [PeerId][], [multiaddr][], or a multiaddr string
 - `protocol`: String that defines the protocol (e.g '/ipfs/bitswap/1.1.0')
 - `callback`: Function with signature `function (err, conn) {}` where `conn` is a [Connection](https://github.com/libp2p/interface-connection) object
 

src/index.js

@@ -319,7 +319,12 @@ class Node extends EventEmitter {
       if (typeof peer === 'string') {
         peer = multiaddr(peer)
       }
+
       const peerIdB58Str = peer.getPeerId()
+      if (!peerIdB58Str) {
+        throw new Error(`peer multiaddr instance or string must include peerId`)
+      }
+
       try {
         p = this.peerBook.get(peerIdB58Str)
       } catch (err) {