Allow topics to be optional when pubKey/privKey is used

lib/modules/whisper/js/embarkjs.js

@@ -32,33 +32,34 @@ __embarkWhisperNewWeb3.setProvider = function (options) {
 
 __embarkWhisperNewWeb3.sendMessage = function (options) {
   var topics, data, ttl, payload;
-  topics = options.topic || options.topics;
+  topics = options.topic;
   data = options.data || options.payload;
   ttl = options.ttl || 100;
   var powTime = options.powTime || 3;
   var powTarget = options.powTarget || 0.5;
 
-  if (topics === undefined) {
-    throw new Error("missing option: topic");
-  }
-
   if (data === undefined) {
     throw new Error("missing option: data");
   }
 
+  if (topics) {
     topics = this.web3.utils.toHex(topics).slice(0, 10);
+  }
 
   payload = JSON.stringify(data);
 
   let message = {
     sig: this.sig, // signs the message using the keyPair ID
     ttl: ttl,
-    topic: topics,
     payload: EmbarkJS.Utils.fromAscii(payload),
     powTime: powTime,
     powTarget: powTarget
   };
 
+  if (topics) {
+    message.topic = topics;
+  }
+
   if (options.pubKey) {
     message.pubKey = options.pubKey; // encrypt using a given pubKey
   } else if(options.symKeyID) {
@@ -67,24 +68,29 @@ __embarkWhisperNewWeb3.sendMessage = function (options) {
     message.symKeyID = this.symKeyID; // encrypts using the sym key ID
   }
 
+  if (topics === undefined && message.symKeyID && !message.pubKey) {
+    throw new Error("missing option: topic");
+  }
+
   this.web3.shh.post(message, function () {
   });
 };
 
 __embarkWhisperNewWeb3.listenTo = function (options, callback) {
-  var topics = options.topic || options.topics;
+  var topics = options.topic;
 
   let promise = new __MessageEvents();
 
+  let subOptions = {};
+
+  if(topics){
     if (typeof topics === 'string') {
       topics = [this.web3.utils.toHex(topics).slice(0, 10)];
     } else {
       topics = topics.map((t) => this.web3.utils.toHex(t).slice(0, 10));
     }
-
-  let subOptions = {
-    topics: topics
-  };
+    subOptions.topics = topics;
+  }
 
   if (options.minPow) {
     subOptions.minPow = options.minPow;