onion-compose/dist/prod/onion-compose.js

Onion style function composition just like koa-compose, but with any number of arguments

function compose(middleware) {
  if (!Array.isArray(middleware)) throw new TypeError('Middleware stack must be an array');

  for (const fn of middleware) {
    if (typeof fn !== 'function') throw new TypeError('Middleware must be composed of functions');
  }

  return function (data, next) {
    // last called middleware
    let index = -1;
    return dispatch(0);

    function dispatch(i) {
      if (i <= index) return Promise.reject(new Error('next() called multiple times'));
      index = i;
      let fn = middleware[i];
      if (i === middleware.length) fn = next;
      if (!fn) return Promise.resolve();

      try {
        // @ts-expect-error - problem with types for the spread operator
        return Promise.resolve(fn(...data, dispatch.bind(null, i + 1)));
      } catch (err) {
        return Promise.reject(err);
      }
    }
  };
}

module.exports = compose;
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