refactor: dht

package.json

@@ -93,7 +93,7 @@
     "libp2p-delegated-peer-routing": "^0.2.2",
     "libp2p-floodsub": "^0.19.0",
     "libp2p-gossipsub": "^0.1.0",
-    "libp2p-kad-dht": "^0.15.3",
+    "libp2p-kad-dht": "libp2p/js-libp2p-kad-dht#refactor/async-iterators",
     "libp2p-mdns": "^0.12.3",
     "libp2p-mplex": "^0.9.1",
     "libp2p-pnet": "~0.1.0",

src/dht.js

@@ -1,43 +1,82 @@
 'use strict'
 
-const nextTick = require('async/nextTick')
 const errCode = require('err-code')
-const promisify = require('promisify-es6')
 
 const { messages, codes } = require('./errors')
 
-module.exports = (node) => {
-  return {
-    put: promisify((key, value, callback) => {
-      if (!node._dht) {
-        return nextTick(callback, errCode(new Error(messages.DHT_DISABLED), codes.DHT_DISABLED))
-      }
+module.exports = (node, DHT, config) => {
+  const dht = new DHT({
+    dialer: {
+      dial: (peer, options) => node.dial(peer, options),
+      dialProtocol: (peer, protocols, options) => {
+        const recordedPeer = node.peerStore.get(peer.toB58String())
 
-      node._dht.put(key, value, callback)
-    }),
-    get: promisify((key, options, callback) => {
-      if (typeof options === 'function') {
-        callback = options
-        options = {}
+        if (recordedPeer) {
+          peer = recordedPeer
+        }
+        return node.dialProtocol(peer, protocols, options)
       }
+    },
+    peerInfo: node.peerInfo,
+    peerStore: node.peerStore,
+    registrar: node.registrar,
+    datastore: this.datastore,
+    ...config
+  })
 
-      if (!node._dht) {
-        return nextTick(callback, errCode(new Error(messages.DHT_DISABLED), codes.DHT_DISABLED))
+  return {
+    /**
+     * Store the given key/value pair in the DHT.
+     * @param {Buffer} key
+     * @param {Buffer} value
+     * @param {Object} [options] - put options
+     * @param {number} [options.minPeers] - minimum number of peers required to successfully put
+     * @returns {Promise<void>}
+     */
+    put: (key, value, options) => {
+      if (!node.isStarted() || !dht.isStarted) {
+        throw errCode(new Error(messages.NOT_STARTED_YET), codes.DHT_NOT_STARTED)
       }
 
-      node._dht.get(key, options, callback)
-    }),
-    getMany: promisify((key, nVals, options, callback) => {
-      if (typeof options === 'function') {
-        callback = options
-        options = {}
+      return dht.put(key, value, options)
+    },
+
+    /**
+     * Get the value to the given key.
+     * Times out after 1 minute by default.
+     * @param {Buffer} key
+     * @param {Object} [options] - get options
+     * @param {number} [options.timeout] - optional timeout (default: 60000)
+     * @returns {Promise<{from: PeerId, val: Buffer}>}
+     */
+    get: (key, options) => {
+      if (!node.isStarted() || !dht.isStarted) {
+        throw errCode(new Error(messages.NOT_STARTED_YET), codes.DHT_NOT_STARTED)
       }
 
-      if (!node._dht) {
-        return nextTick(callback, errCode(new Error(messages.DHT_DISABLED), codes.DHT_DISABLED))
+      return dht.get(key, options)
+    },
+
+    /**
+     * Get the `n` values to the given key without sorting.
+     * @param {Buffer} key
+     * @param {number} nVals
+     * @param {Object} [options] - get options
+     * @param {number} [options.timeout] - optional timeout (default: 60000)
+     * @returns {Promise<Array<{from: PeerId, val: Buffer}>>}
+     */
+    getMany: (key, nVals, options) => {
+      if (!node.isStarted() || !dht.isStarted) {
+        throw errCode(new Error(messages.NOT_STARTED_YET), codes.DHT_NOT_STARTED)
       }
 
-      node._dht.getMany(key, nVals, options, callback)
-    })
+      return dht.getMany(key, nVals, options)
+    },
+
+    _dht: dht,
+
+    start: () => dht.start(),
+
+    stop: () => dht.stop()
   }
 }

src/errors.js

@@ -8,6 +8,7 @@ exports.messages = {
 exports.codes = {
   DHT_DISABLED: 'ERR_DHT_DISABLED',
   PUBSUB_NOT_STARTED: 'ERR_PUBSUB_NOT_STARTED',
+  DHT_NOT_STARTED: 'ERR_DHT_NOT_STARTED',
   ERR_CONNECTION_ENDED: 'ERR_CONNECTION_ENDED',
   ERR_CONNECTION_FAILED: 'ERR_CONNECTION_FAILED',
   ERR_NODE_NOT_STARTED: 'ERR_NODE_NOT_STARTED',

src/index.js

@@ -118,13 +118,8 @@ class Libp2p extends EventEmitter {
     }
 
     // dht provided components (peerRouting, contentRouting, dht)
-    if (this._config.dht.enabled) {
-      const DHT = this._modules.dht
-
-      this._dht = new DHT(this._switch, {
-        datastore: this.datastore,
-        ...this._config.dht
-      })
+    if (this._modules.dht) {
+      this._dht = dht(this, this._modules.dht, this._config.dht)
     }
 
     // start pubsub
@@ -136,7 +131,6 @@ class Libp2p extends EventEmitter {
     // peer and content routing will automatically get modules from _modules and _dht
     this.peerRouting = peerRouting(this)
     this.contentRouting = contentRouting(this)
-    this.dht = dht(this)
 
     this._peerDiscovered = this._peerDiscovered.bind(this)
   }
@@ -186,6 +180,7 @@ class Libp2p extends EventEmitter {
 
     try {
       this.pubsub && await this.pubsub.stop()
+      this._dht && await this._dht.stop()
       await this.transportManager.close()
     } catch (err) {
       if (err) {
@@ -312,6 +307,10 @@ class Libp2p extends EventEmitter {
     if (this._config.pubsub.enabled) {
       this.pubsub && this.pubsub.start()
     }
+
+    if (this._config.dht.enabled) {
+      this._dht && this._dht.start()
+    }
   }
 
   /**

src/peer-store/index.js

@@ -37,24 +37,28 @@ class PeerStore extends EventEmitter {
    * Stores the peerInfo of a new peer.
    * If already exist, its info is updated.
    * @param {PeerInfo} peerInfo
+   * @return {PeerInfo}
    */
   put (peerInfo) {
     assert(PeerInfo.isPeerInfo(peerInfo), 'peerInfo must be an instance of peer-info')
 
+    let peer
     // Already know the peer?
     if (this.peers.has(peerInfo.id.toB58String())) {
-      this.update(peerInfo)
+      peer = this.update(peerInfo)
     } else {
-      this.add(peerInfo)
+      peer = this.add(peerInfo)
 
       // Emit the new peer found
       this.emit('peer', peerInfo)
     }
+    return peer
   }
 
   /**
    * Add a new peer to the store.
    * @param {PeerInfo} peerInfo
+   * @return {PeerInfo}
    */
   add (peerInfo) {
     assert(PeerInfo.isPeerInfo(peerInfo), 'peerInfo must be an instance of peer-info')
@@ -86,11 +90,13 @@ class PeerStore extends EventEmitter {
     })
 
     this.peers.set(peerInfo.id.toB58String(), peerProxy)
+    return peerProxy
   }
 
   /**
    * Updates an already known peer.
    * @param {PeerInfo} peerInfo
+   * @return {PeerInfo}
    */
   update (peerInfo) {
     assert(PeerInfo.isPeerInfo(peerInfo), 'peerInfo must be an instance of peer-info')
@@ -148,6 +154,8 @@ class PeerStore extends EventEmitter {
     if (!recorded.id.pubKey && peerInfo.id.pubKey) {
       recorded.id.pubKey = peerInfo.id.pubKey
     }
+
+    return recorded
   }
 
   /**
@@ -165,6 +173,15 @@ class PeerStore extends EventEmitter {
     return undefined
   }
 
+  /**
+   * Has the info to the given id.
+   * @param {string} peerId b58str id
+   * @returns {boolean}
+   */
+  has (peerId) {
+    return this.peers.has(peerId)
+  }
+
   /**
    * Removes the Peer with the matching `peerId` from the PeerStore
    * @param {string} peerId b58str id

test/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.createPeerInfoFromFixture(1)
+    peerInfo.multiaddrs.add(listenAddr)
+
+    const customOptions = mergeOptions(subsystemOptions, {
+      peerInfo
+    })
+
+    libp2p = await create(customOptions)
+    expect(libp2p._dht._dht.isStarted).to.equal(false)
+
+    await libp2p.start()
+    expect(libp2p._dht._dht.isStarted).to.equal(true)
+
+    await libp2p.stop()
+    expect(libp2p._dht._dht.isStarted).to.equal(false)
+  })
+
+  it('should not start if disabled once libp2p starts', async () => {
+    const [peerInfo] = await peerUtils.createPeerInfoFromFixture(1)
+    peerInfo.multiaddrs.add(listenAddr)
+
+    const customOptions = mergeOptions(subsystemOptions, {
+      peerInfo,
+      config: {
+        dht: {
+          enabled: false
+        }
+      }
+    })
+
+    libp2p = await create(customOptions)
+    expect(libp2p._dht._dht.isStarted).to.equal(false)
+
+    await libp2p.start()
+    expect(libp2p._dht._dht.isStarted).to.equal(false)
+  })
+
+  it('should allow a manual start', async () => {
+    const [peerInfo] = await peerUtils.createPeerInfoFromFixture(1)
+    peerInfo.multiaddrs.add(listenAddr)
+
+    const customOptions = mergeOptions(subsystemOptions, {
+      peerInfo,
+      config: {
+        dht: {
+          enabled: false
+        }
+      }
+    })
+
+    libp2p = await create(customOptions)
+    await libp2p.start()
+    expect(libp2p._dht._dht.isStarted).to.equal(false)
+
+    await libp2p._dht.start()
+    expect(libp2p._dht._dht.isStarted).to.equal(true)
+  })
+})