crucialfelix · May 13, 2024 14:17
diff --git a/base_site.html b/base_site.html
 {% load react_tags %}

 <html>
 <div>
    {# the outer div is replaced by PortalLoader installing a react portal into it. the inner content is fallback or SEO content #}
      {% react_portal NavBarSearch %}
        <form action="{% url 'quick_search' %}" method="get" class="no-js-content header__search-form m-0"><input type="search" class="header__search m-0" size="12" name="search" id="search" placeholder="Enter Web ID or Street" /></form>
      {% endreact_portal %}
 </div>
  {# base_site renders the webpack bundle PortalLoader #}
  <div id="portal-loader"/>{% render_bundle 'PortalLoader' %}
 </body>
 </html>
diff --git a/NavBarSearch.tsx b/NavBarSearch.tsx
 // portals/NavBarSearch.tsx
 // This component is the content of a portal
 import React from "react";
 import SearchSuggest from "/react/components/search/SearchSuggest";

 export default function NavBarSearch() {
  return <SearchSuggest />;
 }
diff --git a/PortalLoader.tsx b/PortalLoader.tsx
 // This PortalLoader is a bundle 
 import React, { lazy, Suspense, useEffect, useState } from "react";
 import { createPortal } from "react-dom";
 import { createRoot } from "react-dom/client";

 // Include these in the bundle since they are on every page
 import NewsLetterSubscribe from "./portals/NewsLetterSubscribe";
 import UserMenu from "./portals/UserMenu";

 import ErrorBoundaryComponent from "./utils/ErrorBoundaryComponent";

 const portals = {
  NewsLetterSubscribe, // not lazy
  UserMenu, // not lazy

  NavBarSearch: lazy(() => import("./portals/NavBarSearch")),
  AdminReact: lazy(() => import("./portals/AdminReact")),
  AffiliatesPage: lazy(() => import("./portals/AffiliatesPage")),
  // etc. no limit
 };

 type Portal = {
  name: string;
  component: React.LazyExoticComponent<React.ComponentType<any>>;
  container: Element;
  props: Record<string, string | number | null>;
 };
 type Portals = Record<string, Portal>;

 /**
 * PortalLoader is a component that will lazy load components and render them as a portal
 * for each element with the attribute data-react-portal
 *
 * It does this when this is first mounted on the page.
 */
 function PortalLoader() {
  // on mount detect any data-react-portal,
  // lazy load those components
  // and render them in portals
  const [components, setComponents] = useState<Portals>({});

  useEffect(() => {
    document.querySelectorAll("[data-react-portal]").forEach((el) => {
      const name = el.getAttribute("data-react-portal");
      const props = el.getAttribute("data-props");
      const page = portals[name];
      if (!page) {
        if (process.env.NODE_ENV === "development") {
          throw Error(`portal not registered: ${name}`);
        } else {
          console.error("portal not registered", name, portals);
          return;
        }
      }
      setComponents((prev) => ({
        ...prev,
        [name]: {
          name,
          component: page,
          container: el,
          props: props ? JSON.parse(props) : {},
        },
      }));
    });
  }, []);

  return (
    <div id="portal-loader">
      {Object.values(components).map((portal) =>
        createPortal(
          <ErrorBoundaryComponent silent={true}>
            <Suspense fallback={null} key={portal.name}>
              <portal.component {...portal.props} />
            </Suspense>
          </ErrorBoundaryComponent>,
          portal.container,
        ),
      )}
    </div>
  );
 }

 const container = document.getElementById("portal-loader");
 // Probably due to the hot loader this is called multiple times
 const didMount = !!container.getAttribute("data-did-mount");

 if (!didMount) {
  const root = createRoot(container);
  root.render(<PortalLoader />);
  container.setAttribute("data-did-mount", "true");
 }
diff --git a/react_portal.html b/react_portal.html
 {# Django templatetag template #}
 <div data-react-portal="{{portal_name}}" class="{{class_name}}" data-props="{{props}}">
  {{ body }}
 </div>
diff --git a/react_tags.py b/react_tags.py
 import json

 from django import template

 from globalapp.utils.template_utils import render_template

 register = template.Library()

 defaults = {"class_name": "", "width": "100%", "height": "auto"}


 @register.tag(name="react_portal")
 def react_portal(parser, token):
    """
    react_portal : Place a React component onto the page, mounted as a React Portal.

    Portals should be in frontend/react/portals
    and should be added to PortalLoader.tsx

    Usage:
        {% react_portal AffiliatesPage %}
            <div class="no-js-content">
                <h2>fallback content</h2>
            </div>
        {% endreact_portal %}

    Any extra supplied args are passed to the react component as props:

        {% react_portal AgentsListings agentId=agentId %}
            <div class="no-js-content">
                <h2>fallback content</h2>
            </div>
        {% endreact_portal %}


    div with ".no-js-content" will only be displayed if the browser does not have
    javascript enabled.
    """
    nodelist = parser.parse("endreact_portal")
    parser.delete_first_token()
    bits = token.split_contents()
    varz = bits[1:]
    if len(varz) == 0:
        raise Exception("Portal name not supplied for react_portal tag")
    portal_name = varz[0]
    if '"' in portal_name:
        raise Exception(
            f"react_portal: Portal names should be supplied without quotes. Got: {portal_name}"
        )
    more_context = {"portal_name": portal_name}
    # Read any additional key=value argument to pass through as React component props
    for key_eq_value in varz[1:]:
        if "=" not in key_eq_value:
            raise Exception(
                f"react_portal invalid prop attribute: {key_eq_value} expected key=value"
            )
        k, v = key_eq_value.split("=")
        more_context[k] = template.Variable(v)

    return ReactPortal(nodelist, more_context)


 class ReactPortal(template.Node):
    def __init__(self, nodelist, more_context):
        self.nodelist = nodelist
        self.more_context = more_context
        self.defaults = defaults.copy()

    def render(self, context):
        # make a child context
        dd = template.Context()
        dd.update(self.defaults)
        for k, v in self.more_context.items():
            dd[k] = v if isinstance(v, str) else v.resolve(context)
        # pass in any extra template tag args to react props
        ignore_args = [
            "width",
            "height",
            "class_name",
            "portal_name",
            "True",
            "False",
            "None",
        ]
        props = {
            key: value for key, value in dd.flatten().items() if key not in ignore_args
        }
        dd["props"] = json.dumps(props)
        dd["body"] = self.nodelist.render(context)
        return render_template("templatetags/react_portal.html", dd.flatten())
diff --git a/react–portals.md b/react–portals.md
diff --git a/webpack.config.js b/webpack.config.js
 // Include PortalLoader as it's own bundle

 module.exports = {
  context: __dirname,
  mode: production ? "production" : "development",
  target: "web",
  entry: {
    // Slim top level public React app that will lazy load 
    PortalLoader: ["./react/PortalLoader.tsx"],
  }
  // rest of your config
 }
	{% load react_tags %}

	<html>
	<div>
	{# the outer div is replaced by PortalLoader installing a react portal into it. the inner content is fallback or SEO content #}
	{% react_portal NavBarSearch %}
	<form action="{% url 'quick_search' %}" method="get" class="no-js-content header__search-form m-0"><input type="search" class="header__search m-0" size="12" name="search" id="search" placeholder="Enter Web ID or Street" /></form>
	{% endreact_portal %}
	</div>
	{# base_site renders the webpack bundle PortalLoader #}
	<div id="portal-loader"/>{% render_bundle 'PortalLoader' %}
	</body>
	</html>
	// portals/NavBarSearch.tsx
	// This component is the content of a portal
	import React from "react";
	import SearchSuggest from "/react/components/search/SearchSuggest";

	export default function NavBarSearch() {
	return <SearchSuggest />;
	}
	// This PortalLoader is a bundle
	import React, { lazy, Suspense, useEffect, useState } from "react";
	import { createPortal } from "react-dom";
	import { createRoot } from "react-dom/client";

	// Include these in the bundle since they are on every page
	import NewsLetterSubscribe from "./portals/NewsLetterSubscribe";
	import UserMenu from "./portals/UserMenu";

	import ErrorBoundaryComponent from "./utils/ErrorBoundaryComponent";

	const portals = {
	NewsLetterSubscribe, // not lazy
	UserMenu, // not lazy

	NavBarSearch: lazy(() => import("./portals/NavBarSearch")),
	AdminReact: lazy(() => import("./portals/AdminReact")),
	AffiliatesPage: lazy(() => import("./portals/AffiliatesPage")),
	// etc. no limit
	};

	type Portal = {
	name: string;
	component: React.LazyExoticComponent<React.ComponentType<any>>;
	container: Element;
	props: Record<string, string \| number \| null>;
	};
	type Portals = Record<string, Portal>;

	/**
	* PortalLoader is a component that will lazy load components and render them as a portal
	* for each element with the attribute data-react-portal
	*
	* It does this when this is first mounted on the page.
	*/
	function PortalLoader() {
	// on mount detect any data-react-portal,
	// lazy load those components
	// and render them in portals
	const [components, setComponents] = useState<Portals>({});

	useEffect(() => {
	document.querySelectorAll("[data-react-portal]").forEach((el) => {
	const name = el.getAttribute("data-react-portal");
	const props = el.getAttribute("data-props");
	const page = portals[name];
	if (!page) {
	if (process.env.NODE_ENV === "development") {
	throw Error(`portal not registered: ${name}`);
	} else {
	console.error("portal not registered", name, portals);
	return;
	}
	}
	setComponents((prev) => ({
	...prev,
	[name]: {
	name,
	component: page,
	container: el,
	props: props ? JSON.parse(props) : {},
	},
	}));
	});
	}, []);

	return (
	<div id="portal-loader">
	{Object.values(components).map((portal) =>
	createPortal(
	<ErrorBoundaryComponent silent={true}>
	<Suspense fallback={null} key={portal.name}>
	<portal.component {...portal.props} />
	</Suspense>
	</ErrorBoundaryComponent>,
	portal.container,
	),
	)}
	</div>
	);
	}

	const container = document.getElementById("portal-loader");
	// Probably due to the hot loader this is called multiple times
	const didMount = !!container.getAttribute("data-did-mount");

	if (!didMount) {
	const root = createRoot(container);
	root.render(<PortalLoader />);
	container.setAttribute("data-did-mount", "true");
	}
	{# Django templatetag template #}
	<div data-react-portal="{{portal_name}}" class="{{class_name}}" data-props="{{props}}">
	{{ body }}
	</div>
	import json

	from django import template

	from globalapp.utils.template_utils import render_template

	register = template.Library()

	defaults = {"class_name": "", "width": "100%", "height": "auto"}


	@register.tag(name="react_portal")
	def react_portal(parser, token):
	"""
	react_portal : Place a React component onto the page, mounted as a React Portal.

	Portals should be in frontend/react/portals
	and should be added to PortalLoader.tsx

	Usage:
	{% react_portal AffiliatesPage %}
	<div class="no-js-content">
	<h2>fallback content</h2>
	</div>
	{% endreact_portal %}

	Any extra supplied args are passed to the react component as props:

	{% react_portal AgentsListings agentId=agentId %}
	<div class="no-js-content">
	<h2>fallback content</h2>
	</div>
	{% endreact_portal %}


	div with ".no-js-content" will only be displayed if the browser does not have
	javascript enabled.
	"""
	nodelist = parser.parse("endreact_portal")
	parser.delete_first_token()
	bits = token.split_contents()
	varz = bits[1:]
	if len(varz) == 0:
	raise Exception("Portal name not supplied for react_portal tag")
	portal_name = varz[0]
	if '"' in portal_name:
	raise Exception(
	f"react_portal: Portal names should be supplied without quotes. Got: {portal_name}"
	)
	more_context = {"portal_name": portal_name}
	# Read any additional key=value argument to pass through as React component props
	for key_eq_value in varz[1:]:
	if "=" not in key_eq_value:
	raise Exception(
	f"react_portal invalid prop attribute: {key_eq_value} expected key=value"
	)
	k, v = key_eq_value.split("=")
	more_context[k] = template.Variable(v)

	return ReactPortal(nodelist, more_context)


	class ReactPortal(template.Node):
	def __init__(self, nodelist, more_context):
	self.nodelist = nodelist
	self.more_context = more_context
	self.defaults = defaults.copy()

	def render(self, context):
	# make a child context
	dd = template.Context()
	dd.update(self.defaults)
	for k, v in self.more_context.items():
	dd[k] = v if isinstance(v, str) else v.resolve(context)
	# pass in any extra template tag args to react props
	ignore_args = [
	"width",
	"height",
	"class_name",
	"portal_name",
	"True",
	"False",
	"None",
	]
	props = {
	key: value for key, value in dd.flatten().items() if key not in ignore_args
	}
	dd["props"] = json.dumps(props)
	dd["body"] = self.nodelist.render(context)
	return render_template("templatetags/react_portal.html", dd.flatten())
	// Include PortalLoader as it's own bundle

	module.exports = {
	context: __dirname,
	mode: production ? "production" : "development",
	target: "web",
	entry: {
	// Slim top level public React app that will lazy load
	PortalLoader: ["./react/PortalLoader.tsx"],
	}
	// rest of your config
	}