express-middleware-utils

Express util middlewares

Install

yarn add express-middleware-utils

Usage

SafeAsync - wrapping async handlers so they throw errors to express error handlers

import { safeAsync } from  'express-middleware-utils'

...

app.use(safeAsync(async (req,res) => {
   // in case error is thrown it will be catched and passed to next so error handlers are called
}))

SomeOf - execute provided middlewares sequentially. Stops executing when middleware passes or throws fatal error. If all middlewares fail, throw error of last middleware in array or provided default error.

import { someOf, UnauthorizedError } from  'express-middleware-utils'

...

app.use(someOf(
  [
    jwtAuthMiddleware(), // It's executed first. If it passes, someOf calls next. If it throws fatal error, someOf calls next with that fatal error.
    apiKeyAuthMiddleware(), // It's executed if first middleware thrown non-fatal error.
  ],
  new UnauthorizedError(), // It's being thrown if none of provided middlewares passed. If error isn't provided, error of last middleware will be used.
  )
)

EveryOf - passes if all provided middlewares pass.

import { everyOf } from  'express-middleware-utils'

...

app.use(everyOf(
  [
    jwtAuthMiddleware(), // It's executed first. If it passes, everyOf calls next middleware. If it throws error, everyOf calls next with that error.
    hasRoles('ADMIN'), // It's executed only if previous middlewares passed.
  ])
)