✨ Add readyCallback

 Closes #22

Signed-off-by: Eduardo San Martin Morote <[email protected]>

Author: posva

Diff for: packages/vuexfire/src/index.js

@@ -122,6 +122,7 @@ function bind ({
   source,
   options: {
     cancelCallback,
+    readyCallback,
   },
 }) {
   if (!isObject(source)) {
@@ -153,6 +154,11 @@ function bind ({
   }
 
   binding.listeners[key] = listener
+
+  // Support for SSR
+  if (readyCallback) {
+    source.once('value', readyCallback)
+  }
 }
 
 function unbind ({ commit, key }) {

Diff for: packages/vuexfire/test/firebase.spec.js

@@ -29,6 +29,11 @@ test.beforeEach(async (t) => {
       unbindItemsRef: firebaseAction(({ unbindFirebaseRef }) => {
         unbindFirebaseRef('items')
       }),
+      bindsWithCallback: firebaseAction(
+        ({ bindFirebaseRef }, { ref, readyCallback }) => {
+          bindFirebaseRef('items', ref, { readyCallback })
+        }
+      ),
     },
     mutations: firebaseMutations,
   })
@@ -120,3 +125,14 @@ test('moves a record when the order changes', async (t) => {
     { '.key': 'c', '.value': 3 },
   ])
 })
+
+test.cb('readyCallback', t => {
+  const foo = t.context.ref.child('foo')
+  t.plan(1)
+  const readyCallback = res => {
+    t.deepEqual(res.val(), { bar: 'bar' })
+    t.end()
+  }
+  t.context.store.dispatch('bindsWithCallback', { ref: foo, readyCallback })
+  foo.child('bar').set('bar')
+})