Im relatively new to React (i'm using preact.js, to be precise) and i am trying to code split out react components using webpack 2.
Im exporting my component as stated in the documentation and i am then importing it on load.
import('./components/List').then((List) => {
render(<List />, document.getElementById('main'));
});
The script loads but i'm not handling the promise callback correctly and finding it hard to see any documentation that shows a working version.
List returns the following object:
I saw your repo. It looks like that your list component doesn't have a export default.
I would add the default and inside your then, when you handle the promise, I'd do it in this way
.then(module => {
const Component = module.default;
render(<Component />, document.getElementById('main'))
})
Related
What I'm trying to achieve is:
Building simple react app - the template is create react app
Copying output file (main.*.js)
Pasting it in another react app
Importing render function to render the first app into the second one
Simple react app code:
interface Props {
greeting: string;
}
export module AppModule {
export const sendGreetings = ({ greeting }: Props) => {
return `Hello ${greeting}`;
};
}
Builder file code:
!function(){"use strict";var n;(n||(n={})).sendGreetings=function(n){var e=n.greeting;return"Hello ".concat(e)}}();
Trying to import this file into another app I get this error:
File 'c:/vscode/test-react-app/test-sc-react/src/main.783e0281.js' is not a module.ts(2306)
Which is obvious. I changed the output file manually to:
export function initApp(){"use strict";var n;(n||(n={})).sendGreetings=function(n){var e=n.greeting;return"Hello ".concat(e)}};
It works but the only function that I'm able to access is initApp but not sendGreetings
I've been struggling with this for a while now and I would really appreciate any helpful suggestions
I used Bit.dev for my components that are used across multiple applications & there is an article regarding your issue
https://blog.bitsrc.io/sharing-react-components-across-multiple-applications-a407b5a15186
I think it would help.
🎯 Solution #1
You can use an iframe to inject your react app:
<iframe src='path-to-your-app.html'/>
🎯 Solution #2
Go with micro-frontend architecture approach. Where a front-end app is decomposed into individual, semi-independent "microapps" working loosely together.
As a starting point, you can try npx create-mf-app instead of the CRA.
You can include your js code directly on run time. You can use window.addEventListener to load js/css incoming from an outside source. You just have to append that js to your document on the load event.
I am trying to test dynamic import in nextjs version 10.2.3, i tried using jest-next-dynamic library which avoid throwing error
TypeError: require.resolveWeak
but when i debug the component in jest test case i get below output and cannot get real component that should be loaded
<ForwardRef(LoadableComponent) .../>
My test case
it('should render Image component from next/Image', () => {
await preloadAll();
defaultProps = getDefaultProps(imgSrcFromAssetsLocation);
const ContainerImage = shallow(<ContainerImage { ...defaultProps } />);
console.log(ContainerImage.debug());
expect(ContainerImage.prop('layout')).toEqual('responsive');
});
After some time i figured out we need to wait for dynamic element to load in test case using waitFor or something similar, documentation of "jest-next-dynamic" does not include this, i found this from below github repo
github repo with example
I am trying to lazy load constant file in react. This constant file is not react component just simple javascript files like below :
// constant.js
export const customFunction = () => {
}
// component.js
const {
customFunction,
} = React.lazy(() => import('./constant.js'));
This I am not able to find in browser under developer tools source option. Also due to this getting customFunction undefined error. This code work if do normal import. customFunction using under useEffect()
import {
customFunction
} from './constant.js';
Do not wrap import statement inside React.lazy. Instead only use import() which returns a Promise and it gets resolved to the contents of the mentioned file
Here is a working example
I am using React Markdown (https://www.npmjs.com/package/react-markdown) to render markdown content in my NextJS project.
When I refresh I have two "toto" & "titi" in my terminal... It is normal or what's wrong with this code?
import Head from 'next/head';
import ReactMarkdown from 'react-markdown';
function Section ({ data }) {
const content = JSON.parse(data.markdown);
const {
title,
sortContent
} = data;
console.log('toto');
return (
<>
<main>
<h1>{title}</h1>
<h1>{sortContent}</h1>
<ReactMarkdown source={content.default} escapeHtml={false} />
</main>
</>
)
}
export async function getServerSideProps (context) {
const json = await import('../../content/article1/data.json');
const content = await import('../../content/fr/article1/content.md');
console.log('titi');
return {
props: {
data: {
title: json.title_content,
sortContent: json.short_content,
markdown: JSON.stringify(content)
}
}
}
}
export default Section
It's part of Reacts development tooling, StrictMode. It is expected and only applies in development mode. You can remove the StrictMode to see it only render the expected number of times, but obviously you lose some development tooling. This tooling can warn you about certain unsafe or unwise practices you might want to avoid such as using legacy APIs.
More details here:
Reactjs Docs
A blog with a good overview
If this is truly the only code you have, then it looks like it's normal. You may have other code that uses these components and that's why in shows twice. But based off the code you have right there, there's no bug.
This is a known side-effect of using React.StrictMode, only in debug mode. You can read more about this here.
Strict mode can’t automatically detect side effects for you, but it
can help you spot them by making them a little more deterministic.
This is done by intentionally double-invoking the following functions:
Class component constructor, render, and shouldComponentUpdate methods
Class component static getDerivedStateFromProps method
Function component bodies
State updater functions (the first argument to setState) Functions passed to useState, useMemo, or useReducer
I know this question has been asked multiple times before but none of the solution seems to work.
I'm trying to use the library 'react-chat-popup' which only renders on client side in a SSR app.(built using next.js framework) The normal way to use this library is to call import {Chat} from 'react-chat-popup' and then render it directly as <Chat/>.
The solution I have found for SSR apps is to check if typedef of window !=== 'undefined' in the componentDidMount method before dynamically importing the library as importing the library normally alone would already cause the window is not defined error. So I found the link https://github.com/zeit/next.js/issues/2940 which suggested the following:
Chat = dynamic(import('react-chat-popup').then(m => {
const {Foo} = m;
Foo.__webpackChunkName = m.__webpackChunkName;
return Foo;
}));
However, my foo object becomes null when I do this. When I print out the m object in the callback, i get {"__webpackChunkName":"react_chat_popup_6445a148970fe64a2d707d15c41abb03"} How do I properly import the library and start using the <Chat/> element in this case?
Next js now has its own way of doing dynamic imports with no SSR.
import dynamic from 'next/dynamic'
const DynamicComponentWithNoSSR = dynamic(
() => import('../components/hello3'),
{ ssr: false }
)
Here is the link of their docs: next js
I've managed to resolve this by first declaring a variable at the top:
let Chat = ''
then doing the import this way in componentDidMount:
async componentDidMount(){
let result = await import('react-chat-popup')
Chat = result.Chat
this.setState({
appIsMounted: true
})
}
and finally render it like this:
<NoSSR>
{this.state.appIsMounted? <Chat/> : null}
</NoSSR>
You may not always want to include a module on server-side. For
example, when the module includes a library that only works in the
browser.
Import the library normally in child component and import that component dynamically on parent component.
https://nextjs.org/docs/advanced-features/dynamic-import#with-no-ssr
This approach worked for me.