lingjing/node_modules/next/dist/esm/build/webpack/loaders/next-metadata-image-loader.js
2026-02-23 09:51:43 +00:00

131 lines
6.0 KiB
JavaScript

/*
* This loader is responsible for extracting the metadata image info for rendering in html
*/ import { existsSync, promises as fs } from 'fs';
import path from 'path';
import loaderUtils from 'next/dist/compiled/loader-utils3';
import { getImageSize } from '../../../server/image-optimizer';
import { imageExtMimeTypeMap } from '../../../lib/mime-type';
import { WEBPACK_RESOURCE_QUERIES } from '../../../lib/constants';
import { normalizePathSep } from '../../../shared/lib/page-path/normalize-path-sep';
import { getLoaderModuleNamedExports } from './utils';
import { installBindings } from '../../swc/install-bindings';
// [NOTE] For turbopack, refer to app_page_loader_tree's write_metadata_item for
// corresponding features.
async function nextMetadataImageLoader(content) {
// Install bindings early so they are definitely available to the loader.
// When run by webpack in next this is already done with correct configuration so this is a no-op.
// In turbopack loaders are run in a subprocess so it may or may not be done.
await installBindings();
const options = this.getOptions();
const { type, segment, pageExtensions, basePath } = options;
const { resourcePath, rootContext: context } = this;
const { name: fileNameBase, ext } = path.parse(resourcePath);
const useNumericSizes = type === 'twitter' || type === 'openGraph';
let extension = ext.slice(1);
if (extension === 'jpg') {
extension = 'jpeg';
}
const opts = {
context,
content
};
const contentHash = loaderUtils.interpolateName(this, '[contenthash]', opts);
const interpolatedName = loaderUtils.interpolateName(this, '[name].[ext]', opts);
const isDynamicResource = pageExtensions.includes(extension);
const pageSegment = isDynamicResource ? fileNameBase : interpolatedName;
const hashQuery = contentHash ? '?' + contentHash : '';
const pathnamePrefix = normalizePathSep(path.join(basePath, segment));
if (isDynamicResource) {
const exportedFieldsExcludingDefault = (await getLoaderModuleNamedExports(resourcePath, this)).filter((name)=>name !== 'default');
// re-export and spread as `exportedImageData` to avoid non-exported error
return `\
import {
${exportedFieldsExcludingDefault.map((field)=>`${field} as _${field}`).join(',')}
} from ${JSON.stringify(// This is an arbitrary resource query to ensure it's a new request, instead
// of sharing the same module with next-metadata-route-loader.
// Since here we only need export fields such as `size`, `alt` and
// `generateImageMetadata`, avoid sharing the same module can make this entry
// smaller.
resourcePath + '?' + WEBPACK_RESOURCE_QUERIES.metadataImageMeta)}
import { fillMetadataSegment } from 'next/dist/lib/metadata/get-metadata-route'
const imageModule = {
${exportedFieldsExcludingDefault.map((field)=>`${field}: _${field}`).join(',')}
}
function getImageMetadata(imageMetadata, idParam, resolvedParams) {
const imageUrl = fillMetadataSegment(${JSON.stringify(pathnamePrefix)}, resolvedParams, ${JSON.stringify(pageSegment)})
const data = {
alt: imageMetadata.alt,
type: imageMetadata.contentType || 'image/png',
url: imageUrl + (idParam ? ('/' + idParam) : '') + ${JSON.stringify(hashQuery)},
}
const { size } = imageMetadata
if (size) {
${type === 'twitter' || type === 'openGraph' ? 'data.width = size.width; data.height = size.height;' : 'data.sizes = size.width + "x" + size.height;'}
}
return data
}
export default async function (props) {
const { generateImageMetadata } = imageModule
const resolvedParams = await props.params
if (generateImageMetadata) {
const imageMetadataArray = await generateImageMetadata({ params: resolvedParams })
return imageMetadataArray.map((imageMetadata, index) => {
const idParam = imageMetadata.id + ''
return getImageMetadata(imageMetadata, idParam, resolvedParams)
})
} else {
return [getImageMetadata(imageModule, '', resolvedParams)]
}
}`;
}
let imageError;
const imageSize = await getImageSize(content).catch((error)=>{
const message = `Process image "${path.posix.join(segment || '/', interpolatedName)}" failed: ${error}`;
imageError = Object.defineProperty(new Error(message), "__NEXT_ERROR_CODE", {
value: "E394",
enumerable: false,
configurable: true
});
return {};
});
if (imageError) {
throw imageError;
}
const imageData = {
...extension in imageExtMimeTypeMap && {
type: imageExtMimeTypeMap[extension]
},
...useNumericSizes && imageSize.width != null && imageSize.height != null ? imageSize : {
sizes: // For SVGs, skip sizes and use "any" to let it scale automatically based on viewport,
// For the images doesn't provide the size properly, use "any" as well.
// If the size is presented, use the actual size for the image.
extension !== 'svg' && imageSize.width != null && imageSize.height != null ? `${imageSize.width}x${imageSize.height}` : 'any'
}
};
if (type === 'openGraph' || type === 'twitter') {
const altPath = path.join(path.dirname(resourcePath), fileNameBase + '.alt.txt');
if (existsSync(altPath)) {
imageData.alt = await fs.readFile(altPath, 'utf8');
}
}
return `\
import { fillMetadataSegment } from 'next/dist/lib/metadata/get-metadata-route'
export default async (props) => {
const imageData = ${JSON.stringify(imageData)}
const imageUrl = fillMetadataSegment(${JSON.stringify(pathnamePrefix)}, await props.params, ${JSON.stringify(pageSegment)})
return [{
...imageData,
url: imageUrl + ${JSON.stringify(hashQuery)},
}]
}`;
}
export const raw = true;
export default nextMetadataImageLoader;
//# sourceMappingURL=next-metadata-image-loader.js.map