Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

fix: re-render Background only if a larger image is needed #782

Merged
merged 6 commits into from
Apr 23, 2021
Merged
Show file tree
Hide file tree
Changes from 1 commit
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
213 changes: 124 additions & 89 deletions src/react-imgix-bg.jsx
Original file line number Diff line number Diff line change
@@ -1,120 +1,155 @@
import React from "react";
import { withContentRect } from "react-measure";
import { PACKAGE_VERSION } from './constants';
import { PACKAGE_VERSION } from "./constants";
import constructUrl from "./constructUrl";
import extractQueryParams from "./extractQueryParams";
import findClosest from "./findClosest";
import targetWidths from "./targetWidths";


const noop = () => {};

const findNearestWidth = (actualWidth) =>
findClosest(actualWidth, targetWidths);

const toFixed = (dp, value) => +value.toFixed(dp);

const BackgroundImpl = (props) => {
const {
measureRef,
measure,
contentRect,
imgixParams = {},
onLoad,
disableLibraryParam,
src,
children,
className = "",
} = props;
const { w: forcedWidth, h: forcedHeight } = imgixParams;
const hasDOMDimensions =
contentRect.bounds.width != null && contentRect.bounds.height != null;
const htmlAttributes = props.htmlAttributes || {};
const dpr = toFixed(2, imgixParams.dpr || global.devicePixelRatio || 1);
const ref = htmlAttributes.ref;
const onRef = (el) => {
measureRef(el);
if (typeof ref === "function") {
ref(el);
}
};
class BackgroundImpl extends React.Component {
constructor(props) {
super(props);
}

shouldComponentUpdate(nextProps) {
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This also needs to handle cases when other props change, e.g. imgixParams, disableLibraryParam, etc.

const contentRect = this.props.contentRect;
const bounds = contentRect.bounds;
const { width: prevWidth, height: prevHeight } = bounds;

const { width, height } = (() => {
const bothWidthAndHeightPassed =
forcedWidth != null && forcedHeight != null;
const nextContentRect = nextProps.contentRect;
const nextBounds = nextContentRect.bounds;
const { width: nextWidth, height: nextHeight } = nextBounds;

if (bothWidthAndHeightPassed) {
return { width: forcedWidth, height: forcedHeight };
// If neither of the previous nor next dimensions are present,
// re-render.
if (!nextWidth || !nextHeight || !prevWidth || !prevHeight) {
return true;
}

if (!hasDOMDimensions) {
return { width: undefined, height: undefined };
// The component has been rendered at least twice by this point
// and both the previous and next dimensions should be defined.
// Only update if the nextWidth is greater than the prevWidth.
if (prevWidth && nextWidth && nextWidth > prevWidth) {
return true;
}
const ar = contentRect.bounds.width / contentRect.bounds.height;

const neitherWidthNorHeightPassed =
forcedWidth == null && forcedHeight == null;
if (neitherWidthNorHeightPassed) {
const width = findNearestWidth(contentRect.bounds.width);
const height = Math.ceil(width / ar);
return { width, height };

// Similarly, only update if the next height is greater than
// the previous height.
if (prevHeight && nextHeight && nextHeight > prevHeight) {
return true;
}
if (forcedWidth != null) {
const height = Math.ceil(forcedWidth / ar);
return { width: forcedWidth, height };
} else if (forcedHeight != null) {
const width = Math.ceil(forcedHeight * ar);
return { width, height: forcedHeight };

return false;
}

render() {
const {
measureRef,
contentRect,
imgixParams = {},
onLoad,
disableLibraryParam,
src,
children,
className = "",
} = this.props;
const { w: forcedWidth, h: forcedHeight } = imgixParams;
const hasDOMDimensions =
contentRect.bounds.width != null && contentRect.bounds.height != null;
const htmlAttributes = this.props.htmlAttributes || {};
const dpr = toFixed(2, imgixParams.dpr || global.devicePixelRatio || 1);
const ref = htmlAttributes.ref;
const onRef = (el) => {
measureRef(el);
if (typeof ref === "function") {
ref(el);
}
};

const { width, height } = (() => {
const bothWidthAndHeightPassed =
forcedWidth != null && forcedHeight != null;

if (bothWidthAndHeightPassed) {
return { width: forcedWidth, height: forcedHeight };
}

if (!hasDOMDimensions) {
return { width: undefined, height: undefined };
}
const ar = contentRect.bounds.width / contentRect.bounds.height;

const neitherWidthNorHeightPassed =
forcedWidth == null && forcedHeight == null;
if (neitherWidthNorHeightPassed) {
const width = findNearestWidth(contentRect.bounds.width);
const height = Math.ceil(width / ar);
return { width, height };
}
if (forcedWidth != null) {
const height = Math.ceil(forcedWidth / ar);
return { width: forcedWidth, height };
} else if (forcedHeight != null) {
const width = Math.ceil(forcedHeight * ar);
return { width, height: forcedHeight };
}
})();
const isReady = width != null && height != null;

const commonProps = {
...htmlAttributes,
};

if (!isReady) {
return (
<div
{...commonProps}
className={`react-imgix-bg-loading ${className}`}
ref={onRef}
>
{children}
</div>
);
}
})();
const isReady = width != null && height != null;

const commonProps = {
...htmlAttributes,
};
const renderedSrc = (() => {
const [rawSrc, params] = extractQueryParams(src);
const srcOptions = {
...params,
fit: "crop",
...imgixParams,
...(disableLibraryParam ? {} : { ixlib: `react-${PACKAGE_VERSION}` }),
width,
height,
dpr,
};

return constructUrl(rawSrc, srcOptions);
})();

const style = {
...htmlAttributes.style,
backgroundImage: `url(${renderedSrc})`,
backgroundSize:
(htmlAttributes.style || {}).backgroundSize !== undefined
? htmlAttributes.style.backgroundSize
: "cover",
};

if (!isReady) {
return (
<div
{...commonProps}
className={`react-imgix-bg-loading ${className}`}
ref={onRef}
>
<div {...commonProps} className={className} ref={onRef} style={style}>
{children}
</div>
);
}

const renderedSrc = (() => {
const [rawSrc, params] = extractQueryParams(src);
const srcOptions = {
...params,
fit: "crop",
...imgixParams,
...(disableLibraryParam ? {} : { ixlib: `react-${PACKAGE_VERSION}` }),
width,
height,
dpr,
};

return constructUrl(rawSrc, srcOptions);
})();

const style = {
...htmlAttributes.style,
backgroundImage: `url(${renderedSrc})`,
backgroundSize:
(htmlAttributes.style || {}).backgroundSize !== undefined
? htmlAttributes.style.backgroundSize
: "cover",
};

return (
<div {...commonProps} className={className} ref={onRef} style={style}>
{children}
</div>
);
};
}
const Background = withContentRect("bounds")(BackgroundImpl);

export { Background, BackgroundImpl as __BackgroundImpl };
58 changes: 56 additions & 2 deletions test/integration/react-imgix.test.jsx
Original file line number Diff line number Diff line change
Expand Up @@ -539,7 +539,7 @@ describe("Background Mode", () => {
expect(bgImageSrcURL.getQueryParamValue("dpr")).toBe("3.44");
});

it("window resize", async () => {
it("window resize smaller", async () => {
const sut = await renderBGAndWaitUntilLoaded(
<div style={{ width: 1000 }} className="fake-window">
<style>{`.bg-img { width: 50%; height: 10px}`}</style>
Expand Down Expand Up @@ -568,7 +568,61 @@ describe("Background Mode", () => {
const bgImageSrcURL = findURIfromSUT(sut);

const expectedWidth = BROWSER_WIDTH / 2;
expect(bgImageSrcURL.getQueryParamValue("w")).toBe("" + expectedWidth);
// We're only resizing if a wider image is required.
// If the browser width shrinks, then the "w" we're
// getting should be greater than or equal to the
// expectedWidth (in this case "w" doesn't change at
// all).
expect(
parseInt(bgImageSrcURL.getQueryParamValue("w"))
).toBeGreaterThanOrEqual(expectedWidth);
});

it("window resize larger", async () => {
ericdeansanchez marked this conversation as resolved.
Show resolved Hide resolved
const sut = await renderBGAndWaitUntilLoaded(
<div style={{ width: 1000 }} className="fake-window">
<style>{`.bg-img { width: 50%; height: 10px}`}</style>
<Background
src={`${src}`}
imgixParams={{
h: 10,
}}
className="bg-img"
>
<div>Content</div>
</Background>
</div>
);

// Before resize:
const startWidth = 500;
const bgImageSrcURLBefore = findURIfromSUT(sut);
expect(parseInt(bgImageSrcURLBefore.getQueryParamValue("w"))).toEqual(
startWidth
);

const fakeWindowEl = document.querySelector(".fake-window");

// Simulate browser resize
const BROWSER_WIDTH = 1080;
fakeWindowEl.style.width = BROWSER_WIDTH + "px";

await new Promise((resolve) => {
setTimeout(resolve, 1000);
});

const bgImageSrcURL = findURIfromSUT(sut);

// After resize:
const expectedWidth = BROWSER_WIDTH / 2;

// We've resized, the "w" should be strictly greater than the startWidth.
expect(parseInt(bgImageSrcURL.getQueryParamValue("w"))).toBeGreaterThan(
startWidth
);
expect(parseInt(bgImageSrcURL.getQueryParamValue("w"))).toEqual(
expectedWidth
);
});

it("can pass ref to component", async () => {
Expand Down