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@Accudio
Created Sep 25, 2021
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Example React component abstraction of an Image CDN. Built with CloudImage and an alias in mind, customise as your setup and provider.
import Image from '../components/Image'
export default function () {
return (
<Image
src="otter.jpg"
alt="an otter standing on a log looking majestic"
srcset={[300, 450, 600, 800, 1000, 1200]}
sizes="100vw"
width="1200"
height="800"
loading="lazy"
className="image-class mb-xl"
/>
)
}
import { useEffect, useState } from "react";
const CDN_BASE = "https://example.imagecdn.com";
const defaults = {
alt: "",
srcset: [300, 450, 600, 800, 1000, 1200],
sizes: "(min-width: 82rem) 80rem, calc(100vw - 2rem)",
loading: "lazy",
className: false,
picClassName: false,
lowdpiQuality: 80,
hidpiQuality: 40
};
const Image = (props) => {
const [fallback, setFallback] = useState("");
const [srcset, setSrcset] = useState("");
const [hidpiSrcset, setHidpiSrcset] = useState("");
useEffect(() => {
const path = `/cdn/${props.src}`;
const lowdpiQuality = props.lowdpiQuality || defaults.lowdpiQuality;
const hidpiQuality = props.hidpiQuality || defaults.hidpiQuality;
const lastWidth = props.srcset[props.srcset.length - 1];
setFallback(createSrc(path, lastWidth, lowdpiQuality));
setSrcset(createSrcset(path, props.srcset, lowdpiQuality));
setHidpiSrcset(createSrcset(path, props.srcset, hidpiQuality));
}, [props.src, props.srcset, props.lowdpiQuality, props.hidpiQuality]);
return (
<pre>
<picture className={props.picClassName || defaults.picClassName}>
<source
media="(-webkit-min-device-pixel-ratio: 1.5)"
srcset={hidpiSrcset}
sizes={props.sizes || defaults.sizes}
/>
<img
className={props.className || defaults.className}
alt={props.alt || defaults.alt}
src={fallback}
srcset={srcset}
sizes={props.sizes || defaults.sizes}
width={props.width}
height={props.height}
loading={props.loading || defaults.loading}
decoding="async"
/>
</picture>
</pre>
);
};
// customise this function depending on your image CDN and setup
function createSrc(path, width, quality) {
return `${CDN_BASE}${path}?w=${width}&q=${quality}`;
}
function createSrcset(path, widths, quality) {
const srcsetArr = widths.map((width) => {
const url = createSrc(path, width, quality);
return `${url} ${width}w`;
});
return srcsetArr.join(",");
}
export default Image;
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