feat: implement softFail option

Author: mkg20001

src/index.js

@@ -25,11 +25,13 @@ function getServerForAddress (addr) {
   * @param {PeerId} options.id - Id for the crypto challenge
   * @param {Transport[]} options.transports - Transport(s) for microswitch
   * @param {Muxer[]} options.muxers - Muxer(s) for microswitch
+  * @param {boolean} options.softFail - Whether to softly fail on listen errors
   */
 class Stardust {
-  constructor ({ transports, muxers, id }) {
+  constructor ({ transports, muxers, id, softFail }) {
     this.switch = new MicroSwitch({ transports, addresses: [], muxers })
     this.id = id
+    this.softFail = softFail
 
     this.discovery = new EE()
     this.discovery.tag = 'stardust'

src/listener.js

@@ -40,8 +40,14 @@ class Listener extends EventEmitter {
       this.emit('listening')
       callback()
     }, err => {
-      this.emit('error', err)
-      callback(err)
+      if (this.client.softFail) {
+        this.emit('listening')
+        callback()
+        // dials will fail, but that's just about it
+      } else {
+        this.emit('error', err)
+        callback(err)
+      }
     })
   }