nsqadmin: fix nodes list links with ipv6 addresses

An ipv6 address needs to be wrapped in "[]" when joined with port
because ":" inside the ipv6 address makes it ambiguous.

Most (all?) of our go code uses net.JoinHostPort() which does this.

nsqadmin/static/js/collections/nodes.js

@@ -18,6 +18,15 @@ var Nodes = Backbone.Collection.extend({
     },
 
     parse: function(resp) {
+        resp['nodes'].forEach(function(n) {
+            var jaddr = n['broadcast_address'];
+            if (jaddr.includes(':')) {
+                // ipv6 raw address contains ':'
+                // it must be wrapped in '[ ]' when joined with port
+                jaddr = '[' + jaddr + ']';
+            }
+            n['broadcast_address_http'] = jaddr + ':' + n['http_port'];
+        });
         return resp['nodes'];
     }
 });

nsqadmin/static/js/views/nodes.hbs

@@ -24,7 +24,7 @@
             {{#each collection}}
             <tr {{#if out_of_date}}class="warning"{{/if}}>
                 <td>{{hostname}}</td>
-                <td><a class="link" href="{{basePath "/nodes"}}/{{broadcast_address}}:{{http_port}}">{{broadcast_address}}</a></td>
+                <td><a class="link" href="{{basePath "/nodes"}}/{{broadcast_address_http}}">{{broadcast_address}}</a></td>
                 <td>{{tcp_port}}</td>
                 <td>{{http_port}}</td>
                 <td>{{version}}</td>