Is it ok to use ReactDOMServer.renderToString in the browser in areas where React isn't directly managing the DOM?

Question

I'm working on an app using Leaflet (via react-leaflet). Leaflet directly manipulates the DOM. The react-leaflet library doesn't change that, it just gives you React components that you can use to control your Leaflet map in a React-friendly way.

In this app, I want to use custom map markers that are divs containing a few simple elements. The way to do that in Leaflet is to set your marker's icon property to a DivIcon, in which you can set your custom HTML. You set that inner HTML by setting the DivIcon's html property to a string containing the HTML. In my case, I want that HTML to be rendered from a React component.

In order to do that, it seems like the correct approach is to use ReactDOMServer.renderToString() to render the Component that I want inside the map marker into a string, which I would then set as the html property of the DivIcon:

MyMarker.js:

import React, { Component } from 'react'
import { renderToString } from 'react-dom/server'
import { Marker } from 'react-leaflet'
import { divIcon } from 'leaflet'

import MarkerContents from './MarkerContents'

export class MyMarker extends Component {
  render() {
    const markerContents = renderToString(<MarkerContents data={this.props.data} />)
    const myDivIcon = divIcon({
      className: 'my-marker',
      html: markerContents
    })

    return (
      <Marker
        position={this.props.position}
        icon={myDivIcon} />
    )
  }
}

However, according to the React docs:

This [renderToString] should only be used on the server.

Is this a strict rule, or is it only meant to dissuade people from circumventing ReactDOM's efficient management of the DOM?

I can't think of another (better) way to accomplish what I'm after. Any comments or ideas would be greatly appreciated.

Answer 1

According to the new documentation: https://reactjs.org/docs/react-dom-server.html

The following methods can be used in both the server and browser environments:

• renderToString()
• renderToStaticMarkup()

Answer 2

I know it is too old question, but since it has not been answered I wanted to share my thoughts.

I was using the same thing, renderToString, but as the documentation recommends not to use it on client-side, I achieved it in another way, by using the react-dom's render method to render the custom component into div

var myDiv = document.createElement('div');

ReactDOM.render(
  <MarkerContents data={this.props.data} />,
  myDiv
);

var myIcon = L.divIcon({ 
    iconSize: new L.Point(50, 50), 
    html: myDiv.innerHTML
});