astro/dist/assets/utils/metadata.js

Astro is a modern site builder with web best practices, performance, and DX front-of-mind.

import { AstroError, AstroErrorData } from "../../core/errors/index.js";
import { lookup as probe } from "../utils/vendor/image-size/lookup.js";
/**
* Extracts image metadata such as dimensions, format, and orientation from the provided image data.
*
* @param {Uint8Array} data - The binary data of the image.
* @param {string} [src] - The source path or URL of the image, used for error messages. Optional.
* @return {Promise<Omit<ImageMetadata, 'src' | 'fsPath'>>} A promise that resolves with the extracted metadata, excluding `src` and `fsPath`.
* @throws {AstroError} Throws an error if the image metadata cannot be extracted.
*/
export async function imageMetadata(data, src) {
	let result;
	try {
		result = probe(data);
	} catch {
		throw new AstroError({
			...AstroErrorData.NoImageMetadata,
			message: AstroErrorData.NoImageMetadata.message(src)
		});
	}
	if (result.height == null || result.width == null || !result.type) {
		throw new AstroError({
			...AstroErrorData.NoImageMetadata,
			message: AstroErrorData.NoImageMetadata.message(src)
		});
	}
	const { width, height, type, orientation } = result;
	const isPortrait = (orientation || 0) >= 5;
	return {
		width: isPortrait ? height : width,
		height: isPortrait ? width : height,
		format: type,
		orientation
	};
}