react-global-from-firebase

React component that sets up a global state from Firebase refs

Install

yarn add react-global-from-firebase or npm install --save react-global-from-firebase

Usage

See the demo for full example.

import * as firebase from 'firebase';
import GlobalFromFirebase from 'react-global-from-firebase';

const ref = firebase.database().ref();

const App = () => (
  <GlobalFromFirebase
    firebaseRefs={{
      foo: ref.child('foo'),
      bar: {
        ref: ref.child('bar'),
        idRef: ref.child('barId') // For caching
      }
    }}
    loadingScreen={() => <h1>Loading</h1>}
  >
    <div>Blah</div>
  </GlobalFromFirebase>
);

Caveats

For some reason, the direct children of GlobalFromFirebase cannot use the global object correctly (since the ref values haven't been set yet). This shouldn't be too much of an issue since you could just put the code that relies on global in a separate component, that'll work.

See the demo for an example.

Props

* = required

Prop | Description | Type ---- | ----------- | ---- firebaseRefs* | The refs that should be loaded into the global object. The ref value will be added to the global object under given key (eg if you do { foo: ref.child('bar') }, global.foo will be set to the value of ref.child('bar')). | object loadingScreen | Node to show while the ref values are loading. Can also take a function that returns an node Signature of the function when passed: function(state: object) => node | node or function onUpdate | Invoked whenever a Firebase value is updated | function(state: object) => any children* | Children of the component | node

Caching

Normally, the object you'd pass to the firebaseRefs prop would look like this:

{
  foo: someRef.child('foo'),
  bar: someRef.child('baz')
}

It is however possible to cache the values of refs. To do this, an idRef is expected (see example below). The idRef is supposed to be a ref that contains some unique ID of the given ref's value. The value of the given ref will only be fetched when this ID changes or when it isn't cached yet. Below is an example with two cached refs:

{
  foo: {
    ref: someRef.child('foo'),
    idRef: someRef.child('fooId')
  },
  bar: {
    ref: someRef.child('baz'),
    idRef: someRef.child('bazId')
  }
}

Caching only makes sense when the ref contains a large value that should be fetched as little as possible.

Development

Installation

yarn install or npm install

Run demo

yarn start or npm start

Run tests

yarn test or npm test

Building

yarn build or npm run build will build the component for publishing to npm and also bundle the demo app.

yarn clean or npm run clean will delete built resources.

Notice that you'll need to temporarily delete .babelrc to be able to build the component (just put it back after you're done building).