feat: state events and query changes (#100)

Author: pgte

src/index.js

@@ -18,7 +18,7 @@ const Circuit = require('libp2p-circuit')
 
 exports = module.exports
 
-const OFFLINE_ERROR_MESSAGE = 'The libp2p node is not started yet'
+const NOT_STARTED_ERROR_MESSAGE = 'The libp2p node is not started yet'
 
 class Node extends EventEmitter {
   constructor (_modules, _peerInfo, _peerBook, _options) {
@@ -29,7 +29,7 @@ class Node extends EventEmitter {
     this.modules = _modules
     this.peerInfo = _peerInfo
     this.peerBook = _peerBook || new PeerBook()
-    this.isOnline = false
+    this._isStarted = false
     this.relayCircuit = null
 
     this.swarm = new Swarm(this.peerInfo, this.peerBook)
@@ -176,7 +176,6 @@ class Node extends EventEmitter {
       }
     })
     this.peerInfo.multiaddrs.replace(maOld, maNew)
-
     const multiaddrs = this.peerInfo.multiaddrs.toArray()
 
     transports.forEach((transport) => {
@@ -194,9 +193,6 @@ class Node extends EventEmitter {
     series([
       (cb) => this.swarm.listen(cb),
       (cb) => {
-        // listeners on, libp2p is on
-        this.isOnline = true
-
         if (ws) {
           // always add dialing on websockets
           this.swarm.transport.add(ws.tag || ws.constructor.name, ws)
@@ -209,10 +205,17 @@ class Node extends EventEmitter {
         cb()
       },
       (cb) => {
+        // TODO: chicken-and-egg problem:
+        // have to set started here because DHT requires libp2p is already started
+        this._isStarted = true
         if (this._dht) {
           return this._dht.start(cb)
         }
         cb()
+      },
+      (cb) => {
+        this.emit('start')
+        cb()
       }
     ], callback)
   }
@@ -221,7 +224,7 @@ class Node extends EventEmitter {
    * Stop the libp2p node by closing its listeners and open connections
    */
   stop (callback) {
-    this.isOnline = false
+    this._isStarted = false
 
     if (this.modules.discovery) {
       this.modules.discovery.forEach((discovery) => {
@@ -236,16 +239,20 @@ class Node extends EventEmitter {
         }
         cb()
       },
-      (cb) => this.swarm.close(cb)
+      (cb) => this.swarm.close(cb),
+      (cb) => {
+        this.emit('stop')
+        cb()
+      }
     ], callback)
   }
 
-  isOn () {
-    return this.isOnline
+  isStarted () {
+    return this._isStarted
   }
 
   ping (peer, callback) {
-    assert(this.isOn(), OFFLINE_ERROR_MESSAGE)
+    assert(this.isStarted(), NOT_STARTED_ERROR_MESSAGE)
     this._getPeerInfo(peer, (err, peerInfo) => {
       if (err) {
         return callback(err)
@@ -256,7 +263,7 @@ class Node extends EventEmitter {
   }
 
   dial (peer, protocol, callback) {
-    assert(this.isOn(), OFFLINE_ERROR_MESSAGE)
+    assert(this.isStarted(), NOT_STARTED_ERROR_MESSAGE)
 
     if (typeof protocol === 'function') {
       callback = protocol
@@ -279,7 +286,7 @@ class Node extends EventEmitter {
   }
 
   hangUp (peer, callback) {
-    assert(this.isOn(), OFFLINE_ERROR_MESSAGE)
+    assert(this.isStarted(), NOT_STARTED_ERROR_MESSAGE)
 
     this._getPeerInfo(peer, (err, peerInfo) => {
       if (err) {