refactor: examples/peer-and-content-routing (#500)

* refactor: examples-peer-and-content-routing

* chore: address review

* chore: review suggestions

Co-Authored-By: Jacob Heun <jacobheun@gmail.com>

examples/peer-and-content-routing/1.js

@@ -1,77 +1,55 @@
 /* eslint-disable no-console */
 'use strict'
 
-const libp2p = require('../../')
+const Libp2p = require('../../')
 const TCP = require('libp2p-tcp')
 const Mplex = require('libp2p-mplex')
 const SECIO = require('libp2p-secio')
 const PeerInfo = require('peer-info')
 const KadDHT = require('libp2p-kad-dht')
-const defaultsDeep = require('@nodeutils/defaults-deep')
-const waterfall = require('async/waterfall')
-const parallel = require('async/parallel')
 
-class MyBundle extends libp2p {
+const delay = require('delay')
-  constructor (_options) {
+
-    const defaults = {
+const createNode = async () => {
-      modules: {
+  const peerInfo = await PeerInfo.create()
-        transport: [ TCP ],
+  peerInfo.multiaddrs.add('/ip4/0.0.0.0/tcp/0')
-        streamMuxer: [ Mplex ],
+
-        connEncryption: [ SECIO ],
+  const node = await Libp2p.create({
-        // we add the DHT module that will enable Peer and Content Routing
+    peerInfo,
-        dht: KadDHT
+    modules: {
-      },
+      transport: [TCP],
-      config: {
+      streamMuxer: [Mplex],
-        dht: {
+      connEncryption: [SECIO],
-          enabled: true,
+      dht: KadDHT
-          kBucketSize: 20
+    },
-        }
+    config: {
+      dht: {
+        enabled: true
       }
     }
-
-    super(defaultsDeep(_options, defaults))
-  }
-}
-
-function createNode (callback) {
-  let node
-
-  waterfall([
-    (cb) => PeerInfo.create(cb),
-    (peerInfo, cb) => {
-      peerInfo.multiaddrs.add('/ip4/0.0.0.0/tcp/0')
-      node = new MyBundle({
-        peerInfo
-      })
-      node.start(cb)
-    }
-  ], (err) => callback(err, node))
-}
-
-parallel([
-  (cb) => createNode(cb),
-  (cb) => createNode(cb),
-  (cb) => createNode(cb)
-], (err, nodes) => {
-  if (err) { throw err }
-
-  const node1 = nodes[0]
-  const node2 = nodes[1]
-  const node3 = nodes[2]
-
-  parallel([
-    (cb) => node1.dial(node2.peerInfo, cb),
-    (cb) => node2.dial(node3.peerInfo, cb),
-    // Set up of the cons might take time
-    (cb) => setTimeout(cb, 300)
-  ], (err) => {
-    if (err) { throw err }
-
-    node1.peerRouting.findPeer(node3.peerInfo.id, (err, peer) => {
-      if (err) { throw err }
-
-      console.log('Found it, multiaddrs are:')
-      peer.multiaddrs.forEach((ma) => console.log(ma.toString()))
-    })
   })
-})
+
+  await node.start()
+  return node
+}
+
+;(async () => {
+  const [node1, node2, node3] = await Promise.all([
+    createNode(),
+    createNode(),
+    createNode()
+  ])
+
+  await Promise.all([
+    node1.dial(node2.peerInfo),
+    node2.dial(node3.peerInfo)
+  ])
+
+  // The DHT routing tables need a moment to populate
+  await delay(100)
+
+  const peer = await node1.peerRouting.findPeer(node3.peerInfo.id)
+
+  console.log('Found it, multiaddrs are:')
+  peer.multiaddrs.forEach((ma) => console.log(ma.toString()))
+})();

examples/peer-and-content-routing/2.js

@@ -1,85 +1,61 @@
 /* eslint-disable no-console */
 'use strict'
 
-const libp2p = require('../../')
+const Libp2p = require('../../')
 const TCP = require('libp2p-tcp')
 const Mplex = require('libp2p-mplex')
 const SECIO = require('libp2p-secio')
 const PeerInfo = require('peer-info')
 const CID = require('cids')
 const KadDHT = require('libp2p-kad-dht')
-const defaultsDeep = require('@nodeutils/defaults-deep')
-const waterfall = require('async/waterfall')
-const parallel = require('async/parallel')
 
-class MyBundle extends libp2p {
+const all = require('it-all')
-  constructor (_options) {
+const delay = require('delay')
-    const defaults = {
+
-      modules: {
+const createNode = async () => {
-        transport: [ TCP ],
+  const peerInfo = await PeerInfo.create()
-        streamMuxer: [ Mplex ],
+  peerInfo.multiaddrs.add('/ip4/0.0.0.0/tcp/0')
-        connEncryption: [ SECIO ],
+
-        // we add the DHT module that will enable Peer and Content Routing
+  const node = await Libp2p.create({
-        dht: KadDHT
+    peerInfo,
-      },
+    modules: {
-      config: {
+      transport: [TCP],
-        dht: {
+      streamMuxer: [Mplex],
-          enabled: true,
+      connEncryption: [SECIO],
-          kBucketSize: 20
+      dht: KadDHT
-        }
+    },
+    config: {
+      dht: {
+        enabled: true
       }
     }
-
-    super(defaultsDeep(_options, defaults))
-  }
-}
-
-function createNode (callback) {
-  let node
-
-  waterfall([
-    (cb) => PeerInfo.create(cb),
-    (peerInfo, cb) => {
-      peerInfo.multiaddrs.add('/ip4/0.0.0.0/tcp/0')
-      node = new MyBundle({
-        peerInfo
-      })
-      node.start(cb)
-    }
-  ], (err) => callback(err, node))
-}
-
-parallel([
-  (cb) => createNode(cb),
-  (cb) => createNode(cb),
-  (cb) => createNode(cb)
-], (err, nodes) => {
-  if (err) { throw err }
-
-  const node1 = nodes[0]
-  const node2 = nodes[1]
-  const node3 = nodes[2]
-
-  parallel([
-    (cb) => node1.dial(node2.peerInfo, cb),
-    (cb) => node2.dial(node3.peerInfo, cb),
-    // Set up of the cons might take time
-    (cb) => setTimeout(cb, 300)
-  ], (err) => {
-    if (err) { throw err }
-
-    const cid = new CID('QmTp9VkYvnHyrqKQuFPiuZkiX9gPcqj6x5LJ1rmWuSySnL')
-
-    node1.contentRouting.provide(cid, (err) => {
-      if (err) { throw err }
-
-      console.log('Node %s is providing %s', node1.peerInfo.id.toB58String(), cid.toBaseEncodedString())
-
-      node3.contentRouting.findProviders(cid, 5000, (err, providers) => {
-        if (err) { throw err }
-
-        console.log('Found provider:', providers[0].id.toB58String())
-      })
-    })
   })
-})
+
+  await node.start()
+  return node
+}
+
+;(async () => {
+  const [node1, node2, node3] = await Promise.all([
+    createNode(),
+    createNode(),
+    createNode()
+  ])
+
+  await Promise.all([
+    node1.dial(node2.peerInfo),
+    node2.dial(node3.peerInfo)
+  ])
+
+  const cid = new CID('QmTp9VkYvnHyrqKQuFPiuZkiX9gPcqj6x5LJ1rmWuSySnL')
+  await node1.contentRouting.provide(cid)
+
+  console.log('Node %s is providing %s', node1.peerInfo.id.toB58String(), cid.toBaseEncodedString())
+
+  // wait for propagation
+  await delay(300)
+
+  const providers = await all(node3.contentRouting.findProviders(cid, { timeout: 3000 }))
+
+  console.log('Found provider:', providers[0].id.toB58String())
+})();

examples/peer-and-content-routing/README.md

@@ -10,31 +10,27 @@ Content Routing is the category of modules that offer a way to find where conten
 
 This example builds on top of the [Protocol and Stream Muxing](../protocol-and-stream-muxing). We need to install `libp2p-kad-dht`, go ahead and `npm install libp2p-kad-dht`. If you want to see the final version, open [1.js](./1.js).
 
-First, let's update our bundle to support Peer Routing and Content Routing.
+First, let's update our config to support Peer Routing and Content Routing.
 
 ```JavaScript
-class MyBundle extends libp2p {
+const Libp2p = require('libp2p')
-  constructor (_options) {
+const KadDHT = require('libp2p-kad-dht')
-    const defaults = {
-      modules: {
-        transport: [ TCP ],
-        streamMuxer: [ Mplex ],
-        connEncryption: [ SECIO ],
-        // we add the DHT module that will enable Peer and Content Routing
-        dht: KadDHT
-      },
-      config: {
-        dht: {
-          // dht must be enabled
-          enabled: true,
-          kBucketSize: 20
-        }
-      }
-    }
 
-    super(defaultsDeep(_options, defaults))
+const node = await Libp2p.create({
+  modules: {
+    transport: [ TCP ],
+    streamMuxer: [ Mplex ],
+    connEncryption: [ SECIO ],
+    // we add the DHT module that will enable Peer and Content Routing
+    dht: KadDHT
+  },
+  config: {
+    dht: {
+      // dht must be enabled
+      enabled: true
+    }
   }
-}
+})
 ```
 
 Once that is done, we can use the createNode function we developed in the previous example to create 3 nodes. Connect node 1 to node 2 and node 2 to node 3. We will use node 2 as a way to find the whereabouts of node 3
@@ -44,22 +40,18 @@ const node1 = nodes[0]
 const node2 = nodes[1]
 const node3 = nodes[2]
 
-parallel([
+await Promise.all([
-  (cb) => node1.dial(node2.peerInfo, cb),
+  node1.dial(node2.peerInfo),
-  (cb) => node2.dial(node3.peerInfo, cb),
+  node2.dial(node3.peerInfo)
-  // Set up of the cons might take time
+])
-  (cb) => setTimeout(cb, 100)
-], (err) => {
-  if (err) { throw err }
 
-  //
+// Set up of the cons might take time
-  node1.peerRouting.findPeer(node3.peerInfo.id, (err, peer) => {
+await delay(100)
-    if (err) { throw err }
 
-    console.log('Found it, multiaddrs are:')
+const peer = await node1.peerRouting.findPeer(node3.peerInfo.id)
-    peer.multiaddrs.forEach((ma) => console.log(ma.toString()))
+
-  })
+console.log('Found it, multiaddrs are:')
-})
+peer.multiaddrs.forEach((ma) => console.log(ma.toString()))
 ```
 
 You should see the output being something like:
@@ -82,17 +74,12 @@ You can find this example completed in [2.js](./2.js), however as you will see i
 Instead of calling `peerRouting.findPeer`, we will use `contentRouting.provide` and `contentRouting.findProviders`.
 
 ```JavaScript
-node1.contentRouting.provide(cid, (err) => {
+await node1.contentRouting.provide(cid)
-  if (err) { throw err }
+console.log('Node %s is providing %s', node1.peerInfo.id.toB58String(), cid.toBaseEncodedString())
 
-  console.log('Node %s is providing %s', node1.peerInfo.id.toB58String(), cid.toBaseEncodedString())
+const provs = await all(node3.contentRouting.findProviders(cid, { timeout: 5000 }))
 
-  node3.contentRouting.findProviders(cid, 5000, (err, providers) => {
+console.log('Found provider:', providers[0].id.toB58String())
-    if (err) { throw err }
-
-    console.log('Found provider:', providers[0].id.toB58String())
-  })
-})
 ```
 
 The output of your program should look like: