feat: add delegated peer and content routing support (#242)

* feat: allow for configuring content and peer routing

* feat: support multiple peer and content routing modules

* docs: add delegated routing example

examples/delegated-routing/src/libp2p-bundle.js

@@ -0,0 +1,78 @@
+// eslint-disable-next-line
+'use strict'
+
+const Libp2p = require('libp2p')
+const Websockets = require('libp2p-websockets')
+const WebSocketStar = require('libp2p-websocket-star')
+const WebRTCStar = require('libp2p-webrtc-star')
+const MPLEX = require('libp2p-mplex')
+const SECIO = require('libp2p-secio')
+const KadDHT = require('libp2p-kad-dht')
+const DelegatedPeerRouter = require('libp2p-delegated-peer-routing')
+const DelegatedContentRouter = require('libp2p-delegated-content-routing')
+
+module.exports = ({peerInfo, peerBook}) => {
+  const wrtcstar = new WebRTCStar({id: peerInfo.id})
+  const wsstar = new WebSocketStar({id: peerInfo.id})
+  const delegatedApiOptions = {
+    host: '0.0.0.0',
+    protocol: 'http',
+    port: '8080'
+  }
+
+  return new Libp2p({
+    peerInfo,
+    peerBook,
+    // Lets limit the connection managers peers and have it check peer health less frequently
+    connectionManager: {
+      maxPeers: 10,
+      pollInterval: 5000
+    },
+    modules: {
+      contentRouting: [
+        new DelegatedContentRouter(peerInfo.id, delegatedApiOptions)
+      ],
+      peerRouting: [
+        new DelegatedPeerRouter(delegatedApiOptions)
+      ],
+      peerDiscovery: [
+        wrtcstar.discovery,
+        wsstar.discovery
+      ],
+      transport: [
+        wrtcstar,
+        wsstar,
+        Websockets
+      ],
+      streamMuxer: [
+        MPLEX
+      ],
+      connEncryption: [
+        SECIO
+      ],
+      dht: KadDHT
+    },
+    config: {
+      peerDiscovery: {
+        webrtcStar: {
+          enabled: false
+        },
+        websocketStar: {
+          enabled: false
+        }
+      },
+      dht: {
+        kBucketSize: 20
+      },
+      relay: {
+        enabled: true,
+        hop: {
+          enabled: false
+        }
+      },
+      EXPERIMENTAL: {
+        dht: false
+      }
+    }
+  })
+}