Middleware framework for AWS lambdas

with-middlewares.js

const withMiddlewares = (handler, middlewares = []) => (event, context, callback) => {
  const chainMiddlewares = ([firstMiddleware, ...restOfMiddlewares]) => {
    if (firstMiddleware) {
      return (e, c) => {
        try {
          return firstMiddleware(e, c, chainMiddlewares(restOfMiddlewares))
        } catch (error) {
          return Promise.reject(error)
        }
      }
    }

    return handler
  }

  chainMiddlewares(middlewares)(event, context)
    .then(result => callback(null, result))
    .catch((err) => {
      callback(err, null)
    })
}

module.exports = withMiddlewares