copyNextAssets.js

const { join } = require("path");
const { copySync, existsSync } = require("fs-extra");
const { logTitle } = require("../helpers/logger");
const { NEXT_DIST_DIR } = require("../config");

// Copy the NextJS' static assets from NextJS distDir to Netlify publish folder.
// These need to be available for NextJS to work.
const copyNextAssets = (publishPath) => {
  const staticAssetsPath = join(NEXT_DIST_DIR, "static");
  if (!existsSync(staticAssetsPath)) {
    throw new Error(
      "No static assets found in .next dist (aka no /.next/static). Please check your project configuration. Your next.config.js must be one of `serverless` or `experimental-serverless-trace`. Your build command should include `next build`."
    );
  }
  logTitle("💼 Copying static NextJS assets to", publishPath);
  copySync(staticAssetsPath, join(publishPath, "_next", "static"), {
    overwrite: false,
    errorOnExist: true,
  });
};

module.exports = copyNextAssets;