TheLazy.Dev
Portfolio GitHub

Blog

rescript |emotion

Simple Server Side CSS with ReScript, React and Emotion

kevanstannard

Kevan Stannard

Posted on December 9, 2020

Simple Server Side CSS with ReScript, React and Emotion

Introduction

A simple introduction to using server side CSS with ReScript, React and Emotion CSS.

ReScript version: bs-platform@8.3.3

NPM Packages

First install the packages we need.

npm i @emotion/css @emotion/server react react-dom reason-react
Enter fullscreen mode Exit fullscreen mode

This example is using the following versions:

@emotion/css@11.0.0
@emotion/server@11.0.0
react@17.0.1
react-dom@17.0.1
reason-react@0.9.1
Enter fullscreen mode Exit fullscreen mode

Update bsconfig.json

Add reason-react to bs-dependencies:

"bs-dependencies": ["reason-react"],
Enter fullscreen mode Exit fullscreen mode

Create the Emotion bindings

In a file Emotion.res add the following bindings.

module Css = {
  @bs.module("@emotion/css")
  external css: {..} => string = "css"
}

module Server = {
  @bs.module("@emotion/server")
  external renderStylesToString: string => string = "renderStylesToString"
}
Enter fullscreen mode Exit fullscreen mode

Render a component with some styles

In a test file, create some styles to use:

module Styles = {
  open Emotion.Css
  let container = css({"border": "1px solid black"})
}
Enter fullscreen mode Exit fullscreen mode

Create a React component that uses the styles:

module Container = {
  @react.component
  let make = (~children) => {
    <div className={Styles.container}> {children} </div>
  }
}
Enter fullscreen mode Exit fullscreen mode

Render the component with Emotion styles:

let el = <Container> {ReasonReact.string("Hello")} </Container>


let html =
  el
  ->ReactDOMServer.renderToStaticMarkup
  ->Emotion.Server.renderStylesToString
Enter fullscreen mode Exit fullscreen mode

Which generates the following code (reformatted here for readability):

<style data-emotion="css 1r0rfp">
  .css-1r0rfp{border:1px solid blue;}
</style>
<div class="css-1r0rfp">Hello</div>
Enter fullscreen mode Exit fullscreen mode

Note

If you would prefer stronger type safety with Emotion, you may like to use bs-css.

💖 💪 🙅 🚩
kevanstannard
Kevan Stannard

Posted on December 9, 2020

Join Our Newsletter. No Spam, Only the good stuff.

Sign up to receive the latest update from our blog.

Related

Simple Server Side CSS with ReScript, React and Emotion
rescript Simple Server Side CSS with ReScript, React and Emotion

December 9, 2020