Standalone React components with Rails6 / Webpacker - ruby-on-rails

Question

I'd like to know how to / [accepted way] to add standalone react components to specific pages in rails, using webpacker. The use case is that I have a Rails6 app that I intend to use Rails functionalities for the view, instead of a full React SPA. I would, however, like to use specific custom react components in specific rails views. The app has webpacker installed and configured for react.
Questions I have:
is react-rails the right gem / pattern for this usage? I have tried using it and it does perfectly fill the use case, but I was wondering if it can be done without adding this gem since it since it seems like webpacker itself has react support.
Is it required that the webpacker <%= javascript_pack_tag => should always go in an application layout (head tag), and dynamically render a pack to the end of the body(appendChild), like the examples say? I'd rather include the pack tag in a view, and have it render directly to a div I've specified. (code for this below)
How does one send react props to a standalone react component that is rendered by the <%= javascript_pack_tag => ? Would the component have to be written to fetch any data it needs on mount?
Things I've tried:
I looked through the documentation for webpacker, and as many of the issues I could find using the keywords "standalone" and "react" and couldn't find anything.
Sample project below: it works.. but I'm not sure if it's the right way to do this and I'm not sure how to address question 3 from above (regarding passing props)
Initialize
rails new petstore --webpack=react
bin/rails generate scaffold Pet pet_type:string pet_name:string
bin/rails db:migrate
package.json
{
"name": "petstore",
"private": true,
"dependencies": {
"#babel/preset-react": "^7.12.10",
"#rails/actioncable": "^6.0.0",
"#rails/activestorage": "^6.0.0",
"#rails/ujs": "^6.0.0",
"#rails/webpacker": "5.2.1",
"babel-plugin-transform-react-remove-prop-types": "^0.4.24",
"prop-types": "^15.7.2",
"react": "^17.0.1",
"react-dom": "^17.0.1",
"turbolinks": "^5.2.0"
},
"version": "0.1.0",
"devDependencies": {
"webpack-dev-server": "^3.11.2"
}
}
config/webpacker.yml
default: &default
source_path: app/javascript
source_entry_path: packs
public_root_path: public
public_output_path: packs
cache_path: tmp/cache/webpacker
webpack_compile_output: true
# Additional paths webpack should lookup modules
# ['app/assets', 'engine/foo/app/assets']
additional_paths: []
# Reload manifest.json on all requests so we reload latest compiled packs
cache_manifest: false
# Extract and emit a css file
extract_css: false
static_assets_extensions:
- .jpg
- .jpeg
- .png
- .gif
- .tiff
- .ico
- .svg
- .eot
- .otf
- .ttf
- .woff
- .woff2
extensions:
- .jsx
- .mjs
- .js
- .sass
- .scss
- .css
- .module.sass
- .module.scss
- .module.css
- .png
- .svg
- .gif
- .jpeg
- .jpg
development:
<<: *default
compile: true
# Reference: https://webpack.js.org/configuration/dev-server/
dev_server:
https: false
host: localhost
port: 3035
public: localhost:3035
hmr: false
# Inline should be set to true if using HMR
inline: true
overlay: true
compress: true
disable_host_check: true
use_local_ip: false
quiet: false
pretty: false
headers:
'Access-Control-Allow-Origin': '*'
watch_options:
ignored: '**/node_modules/**'
test:
<<: *default
compile: true
# Compile test packs to a separate directory
public_output_path: packs-test
production:
<<: *default
# Production depends on precompilation of packs prior to booting for performance.
compile: false
# Extract and emit a css file
extract_css: true
# Cache manifest.json for performance
cache_manifest: true
app/javascript/components/PetAnimation.js
import React from "react";
import PropTypes from "prop-types"
class PetAnimation extends React.Component {
constructor(props) {
super(props);
this.state = {
petType: props.petType,
};
}
render() {
return (
<div>Cute Pet Animation based on Pet Type and other imported libraries</div>
)
}
}
PetAnimation.propTypes = {
petType: PropTypes.string
};
export default PetAnimation;
app/javascript/packs/pet_animation.js
import React from 'react'
import ReactDOM from 'react-dom'
import PetAnimation from "../components/PetAnimation";
document.addEventListener('DOMContentLoaded', () => {
const rootElement = document.getElementById("pet-animation");
if (rootElement != null) {
ReactDOM.render(<PetAnimation/>, rootElement)
}
})
app/views/pets/show.html.erb
<p id="notice"><%= notice %></p>
<p>
<strong>Pet type:</strong>
<%= #pet.pet_type %>
</p>
<p>
<strong>Pet name:</strong>
<%= #pet.pet_name %>
</p>
<p>
<%= javascript_pack_tag 'pet_animation', 'data-turbolinks-track': 'reload' %>
<div id="pet-animation"></div>
</p>
<%= link_to 'Edit', edit_pet_path(#pet) %> |
<%= link_to 'Back', pets_path %>
... and it works, sort of: