@robinbobin/mimetype-constants/js/src/extend.js

Extensible MIME constants with typescript support

import { omit } from 'radashi';
import { mimeTypes } from './mimeTypes';
export function extend(typeGroups) {
    const extendedMimeTypes = {
        ...mimeTypes
    };
    for (const [type, subtypes] of Object.entries(typeGroups)) {
        const existingSubtypes = Object.keys(extendedMimeTypes[type] ?? {});
        const subtypeKeysToOmit = Object.keys(subtypes).filter(subtypeKey => existingSubtypes.includes(subtypeKey));
        const filteredSubtypes = omit(subtypes, subtypeKeysToOmit);
        extendedMimeTypes[type] = {
            ...extendedMimeTypes[type],
            ...filteredSubtypes
        };
    }
    return extendedMimeTypes;
}