Inline Middlewares

Sometimes you want to create handlers that serve a very small need and that are not necessarily re-usable. In such cases, you probably will need to hook only into one of the different phases (before, after or onError).

In these cases you can use inline middlewares which are shortcut functions to hook logic into Middy's control flow.

Let's see how inline middlewares work with a simple example:

import middy from '@middy/core'

const lambdaHandler = (event, context) => {
  // do stuff
}

export const handler = middy()
  .before(async (request) => {
    // do something in the before phase
  })
  .after(async (request) => {
    // do something in the after phase
  })
  .onError(async (request) => {
    // do something in the on error phase
  })
  .handler(lambdaHandler)

As you can see above, a middy instance also exposes the before, after and onError methods to allow you to quickly hook in simple inline middlewares.