Treating firebase as the single source of true: Replacing redux state always when a new event come

src/reducers/index.js

@@ -34,6 +34,7 @@ const indexReducer = (state: Object = initialState, action) => {
         if (!(statePathArr && statePathArr.length)) return state;
 
         switch (eventName) {
+          case 'child_added': return state.mergeDeepIn(statePathArr, fromJS(value));
           case 'child_removed': return state.removeIn(statePathArr);
           default: return state.setIn(statePathArr, fromJS(value));
         }

src/store/middlewares/firebase/index.js

@@ -64,22 +64,14 @@ export function startFirebase({ store, userId }) {
   _databaseRef = firebase.database().ref(`users/${userId}/`);
   console.debug('[FIREBASE] Connected.');
 
-  _databaseRef.once('value', snapshot => {
-    _lastState = fromJS(snapshot.val()) || null;
-
-    watchFirebaseFromMap({
-      callback({ eventName, firebasePathArr, statePathArr, value }) {
-        if (_lastState === undefined) return;
-        store.dispatch(firebaseReceivedEvent({ eventName, firebasePathArr, statePathArr, value }));
-        _lastState = store.getState();
-      },
-      debug: __DEV__,
-      map: mapFirebaseToState,
-      ref: _databaseRef,
-    });
-  }, (...args) => {
-    console.error('[FIREBASE] Something went wrong getting data from the server', ...args);
-    _lastState = null;
+  watchFirebaseFromMap({
+    callback({ eventName, firebasePathArr, statePathArr, value }) {
+      store.dispatch(firebaseReceivedEvent({ eventName, firebasePathArr, statePathArr, value }));
+      _lastState = store.getState();
+    },
+    debug: __DEV__,
+    map: mapFirebaseToState,
+    ref: _databaseRef,
   });
 }
 

src/store/middlewares/firebase/lib.js

@@ -113,7 +113,7 @@ export function createFirebaseHandler(
 }
 
 export const addFirebaseListener = (
-  { blacklist, callback, debug, eventName, ref },
+  { blacklist, callback, debug, eventName, ref, ...rest },
 ) => {
   const fullPath = getPathFromRef(ref);
   let message = `[FIREBASE] Watching ${fullPath} ${eventName}`;
@@ -122,7 +122,7 @@ export const addFirebaseListener = (
     message = `${message}, except ${blacklist.join(', ')}`;
   }
 
-  if (debug) console.debug(message);
+  if (debug && !rest.isRecursiveCall) console.debug(message);
 
   if (eventName === 'children' || Array.isArray(eventName)) {
     const eventNames = Array.isArray(eventName)
@@ -133,9 +133,10 @@ export const addFirebaseListener = (
       addFirebaseListener({
         blacklist,
         callback,
-        debug: false,
+        debug,
         eventName: realEventName,
         ref,
+        isRecursiveCall: true,
       });
     });