refactor: async routing (#489)

* feat: async routing

* chore: put dht extra api commands under content routing

* chore: add default option to createPeerInfo

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

* chore: address review

* chore: rm dlv

test/content-routing/dht/configuration.node.js

@@ -0,0 +1,92 @@
+'use strict'
+/* eslint-env mocha */
+
+const chai = require('chai')
+chai.use(require('dirty-chai'))
+const { expect } = chai
+
+const mergeOptions = require('merge-options')
+const multiaddr = require('multiaddr')
+
+const { create } = require('../../../src')
+const { baseOptions, subsystemOptions } = require('./utils')
+const peerUtils = require('../../utils/creators/peer')
+
+const listenAddr = multiaddr('/ip4/127.0.0.1/tcp/0')
+
+describe('DHT subsystem is configurable', () => {
+  let libp2p
+
+  afterEach(async () => {
+    libp2p && await libp2p.stop()
+  })
+
+  it('should not exist if no module is provided', async () => {
+    libp2p = await create(baseOptions)
+    expect(libp2p._dht).to.not.exist()
+  })
+
+  it('should exist if the module is provided', async () => {
+    libp2p = await create(subsystemOptions)
+    expect(libp2p._dht).to.exist()
+  })
+
+  it('should start and stop by default once libp2p starts', async () => {
+    const [peerInfo] = await peerUtils.createPeerInfo(1)
+    peerInfo.multiaddrs.add(listenAddr)
+
+    const customOptions = mergeOptions(subsystemOptions, {
+      peerInfo
+    })
+
+    libp2p = await create(customOptions)
+    expect(libp2p._dht.isStarted).to.equal(false)
+
+    await libp2p.start()
+    expect(libp2p._dht.isStarted).to.equal(true)
+
+    await libp2p.stop()
+    expect(libp2p._dht.isStarted).to.equal(false)
+  })
+
+  it('should not start if disabled once libp2p starts', async () => {
+    const [peerInfo] = await peerUtils.createPeerInfo(1)
+    peerInfo.multiaddrs.add(listenAddr)
+
+    const customOptions = mergeOptions(subsystemOptions, {
+      peerInfo,
+      config: {
+        dht: {
+          enabled: false
+        }
+      }
+    })
+
+    libp2p = await create(customOptions)
+    expect(libp2p._dht.isStarted).to.equal(false)
+
+    await libp2p.start()
+    expect(libp2p._dht.isStarted).to.equal(false)
+  })
+
+  it('should allow a manual start', async () => {
+    const [peerInfo] = await peerUtils.createPeerInfo(1)
+    peerInfo.multiaddrs.add(listenAddr)
+
+    const customOptions = mergeOptions(subsystemOptions, {
+      peerInfo,
+      config: {
+        dht: {
+          enabled: false
+        }
+      }
+    })
+
+    libp2p = await create(customOptions)
+    await libp2p.start()
+    expect(libp2p._dht.isStarted).to.equal(false)
+
+    await libp2p._dht.start()
+    expect(libp2p._dht.isStarted).to.equal(true)
+  })
+})