React wrapper

React wrapper is a library that allows to use Vue components inside a React project. It tries to provide the same APIs that Vue has, but in a React way: props, events, slots, scoped slots...

Usage guide

To start using this library, simply add it to your React project dependencies, together with react, react-dom, and vue:

# or pnpm or yarn
npm install @empathyco/react-wrapper react react-dom vue

After installing these dependencies, you can start using the ReactWrapper. To do so, you just have to use it like a normal React component, the only required prop is the component one, which must be passed with the Vue component to render.

1// File hello-world.vue
2<template>
3  <h1>Hello world!</h1>
4</template>

1// File App.ts
2import { ReactWrapper } from '@empathco/react-wrapper';
3import HelloWorld from './hello-world.vue';
4import React from 'react';
5
6function App() {
7  return (
8    <main>
9      <ReactWrapper component={HelloWorld} />
10    </main>
11  );
12}

Props

To pass some props to the Vue component rendered by ReactWrapper, just pass them as you would with a normal React component. ReactWrapper will forward them to the Vue component:

1// File message.vue
2<template>
3  <h1>{{ message }}</h1>
4</template>
5<script>
6  export default {
7    props: ['message']
8  };
9</script>

1// File App.tsx
2import { ReactWrapper } from '@empathyco/react-wrapper';
3import Message from './message.vue';
4import React from 'react';
5
6function App() {
7  return (
8    <main>
9      <ReactWrapper component={Message} message={'Hello World!'} />
10    </main>
11  );
12}

Note that there are some special properties that shouldn't be used. The on, children and slots props are used to expose other Vue APIs. This is explained in the events and children & slots sections.

Events

While React treats events callbacks as normal props, Vue makes a distinction between them and the normal ones. That's why, to use events in the ReactWrapper you have to use a special prop called on. This prop is just a dictionary of events callbacks, where the key is the event name, and the value is the callback itself, which can have a payload associated.

1// File button.vue
2<template>
3  <button @click="emitClick">Click me!</button>
4</template>
5<script>
6  export default {
7    methods: {
8      emitClick() {
9        this.$emit('click:button', 'Button was clicked');
10      }
11    }
12  };
13</script>

1// File App.tsx
2import { ReactWrapper } from '@empathyco/react-wrapper';
3import Button from './button.vue';
4import React from 'react';
5
6function App() {
7  return (
8    <main>
9      <ReactWrapper
10        component={Button}
11        on={{ 'click:button': payload => console.log('Click', payload) }}
12      />
13    </main>
14  );
15}

Children & Slots

Vue has an advanced API for handling the children of elements. Apart from the traditional default slot which allows you to pass some children to a component, it provides a way for creating named and scoped slots. Named slots allows passing children to different part of a component, while scoped slots provides a way for raising data to the component that provides the slots.

Default slots

To use default slots there are 3 ways: nesting the children inside the component, or using the children & slots.default props.

1// File title.vue
2<template>
3  <h1><slot /></h1>
4</template>
5<script>
6  export default {};
7</script>

1// File App.tsx
2import { ReactWrapper } from '@empathyco/react-wrapper';
3import Title from './title.vue';
4import React from 'react';
5
6function App() {
7  return (
8    <main>
9      <ReactWrapper component={Button}>
10        Hello <strong>World</strong>
11      </ReactWrapper>
12    </main>
13  );
14}

1// File App.tsx
2import { ReactWrapper } from '@empathyco/react-wrapper';
3import Title from './title.vue';
4import React from 'react';
5
6function App() {
7  return (
8    <main>
9      <ReactWrapper
10        component={Title}
11        slots={{
12          default: ['Hello', <strong>World</strong>]
13        }}
14      />
15    </main>
16  );
17}

Scoped & Named slots

1// File article-preview.vue
2<template>
3  <article>
4    <h1>{{ article.title }}</h1>
5    <span><slot name="author" :author="author" /></span>
6    <div>{{ article.body }}</div>
7    <slot name="extra" />
8  </article>
9</template>
10<script>
11  export default {
12    props: ['article'],
13    computed: {
14      author() {
15        return article.author || 'Anonymous';
16      }
17    }
18  };
19</script>

1// File App.tsx
2import { ReactWrapper } from '@empathyco/react-wrapper';
3import ArticlePreview from './article-preview.vue';
4import React from 'react';
5
6const article = {
7  title: 'Vue slots API',
8  body: 'A short guide about how to use vue slots.'
9};
10
11function App() {
12  return (
13    <main>
14      <ReactWrapper
15        component={ArticlePreview}
16        article={article}
17        slots={{
18          author: computedAuthor => <strong>computedAuthor</strong>,
19          extra: <a href='#'>Read more</a>
20        }}
21      />
22    </main>
23  );
24}

Architecture

ReactWrapper works by creating an internal Vue instance that is mounted inside the ReactWrapper component. Vue rendered content is inserted inside the div element rendered by the ReactWrapper, taking control of the DOM tree from that part.

Proxying APIs is the "easy" part of this library. React flexibility helps when exposing Vue APIs like events or slots. ReactWrapper only has to sync the props received with its internal Vue instance ones. Whenever the props change, it extracts them again, and notifies the Vue instance about them.

The biggest challenge of this library is the DOM reconciliation. As the DOM is handled by both Vue and React, they expect to have full control of it, and if one library makes a change to the DOM. But, because ReactWrapper renders a div, and Vue content is inserted inside it, there are no problems. React has control of the app until this div, and Vue from that point.

On the other hand, slots are a bit more complex. Slots work by using a special Vue component, VueChildrenWrapper. This component renders a div, and receives React virtual nodes as props. When the VueChildrenWrapper component is mounted, it renders the React nodes inside it. Just like the ReactWrapper does with the children nodes.

The problematic part here is unmounting a component which has animations. When the Vue component is destroyed, the React one should be destroyed too. The challenge is that Vue fires beforeDestroy and destroyed hooks before the component is removed from the DOM, and then it runs the leaving animations if it has. So the solution is to observe the nodes with a MutationObserver. If the nodes are detached, then it is safe to unmount the React component too.