bring blob message decoding helper method over to observable flow

Author: jimmcgaw

src/store/epics/chatEpics.js

@@ -30,12 +30,6 @@ import ChatHandler from './helpers/ChatHandler';
 import { combineEpics } from 'redux-observable';
 import createDetectVisibilityObservable from './helpers/createDetectPageVisibilityObservable';
 
-// let wsUrl = `${window.location.origin.replace('http', 'ws')}/api/ws/messages/all`;
-// if (Capacitor.isNativePlatform()) {
-//   // wsUrl = 'wss://www.leapchat.org/api/ws/messages/all'
-//   wsUrl = 'ws://10.0.2.2:8080/api/ws/messages/all'
-// }
-
 import { authUrl, wsUrl } from './helpers/urls';
 
 export const chatHandler = new ChatHandler(wsUrl);
@@ -130,6 +124,12 @@ function getAuthRequestSettings({ mID }) {
   return settings;
 }
 
+// Helper for parsing response from Go API
+//
+// From https://stackoverflow.com/a/36183085
+const b64toBlob = (base64, type = 'application/octet-stream') =>
+      fetch(`data:${type};base64,${base64}`).then(res => res.blob());
+
 const connectionAlertTtlSeconds = 4;
 
 const initConnectionEpic = (action$) =>