next.config.js

const withPlugins = require('next-compose-plugins')
const withMdxEnhanced = require('next-mdx-enhanced')
const checkEnv = require('@47ng/check-env').default
const nodePath = require('path')
const readingTime = require('reading-time')

checkEnv({
  required: ['NEXT_PUBLIC_DEPLOYMENT_URL'],
})

const isProd = process.env.NODE_ENV === 'production'

const useURL = (path) =>
  `${process.env.NEXT_PUBLIC_DEPLOYMENT_URL}${path || ''}`

const nextConfig = {
  assetPrefix: '',
}
module.exports = withPlugins(
  [
    withMdxEnhanced({
      layoutPath: 'src/layouts',
      defaultLayout: true,
      fileExtensions: ['mdx'],
      remarkPlugins: [
        require('remark-slug'),
        require('remark-footnotes'),
        require('remark-code-titles'),
        //require('@fec/remark-a11y-emoji')
      ],
      rehypePlugins: [require('mdx-prism')],
      extendFrontMatter: {
        process: (mdxContent, frontMatter) => {
          const pagesDir = nodePath.resolve(__dirname, 'src/pages')
          // Somehow the __resourcePath does not start with a /:
          const path = ('/' + frontMatter.__resourcePath)
            .replace(pagesDir, '')
            .replace('.mdx', '')
            .replace('.tsx', '')
            .replace(/^\/index$/, '/')
            .replace(/\/index$/, '')
          return {
            path,
            url: useURL(path),
            readingTime: readingTime(mdxContent),
          }
        },
      },
    }),
  ],
  nextConfig,
)