http-errors-express

Express middleware for handling errors generated or compatible with the http-errors module. Sends errors to client using JSON, for example:

import createError from 'http-errors'

// ...

app.post('/pay', (req, res, next) => {
  next(createError(402, 'Your balance is too low.', {
    detail: {
      currentBalance: 100,
      price: 150,
    },
  }))
})

// ...

would send the following JSON response payload to the client:

{
  "error": {
    "name": "PaymentRequiredError",
    "message": "Your balance is too low.",
    "detail": {
      "currentBalance": 100,
      "price": 150
    }
  }
}

See ./test/index.js for more examples.

Install

npm install --save http-errors-express

Usage

httpErrors(opts)

All options are optional.

• opts.before function with (err, req, isExposed, cb) signature that can be used to log errors for example. Defaults to logging with console.error for unexposed errors. Can ignore the cb and instead return a promise.
• opts.formatError function with (err, req, isExposed) signature which formats errors before passing to res.json

Returns an Express middleware. The HTTP response is only sent after the before function's callback is called. This is useful if we want to include an error ID received from a remote error logging service (e.g. service) as part of the response.

If an exposed error has a detail property, it will by default be included as part of the JSON response.

import express from 'express'
import httpErrors from 'http-errors-express'

const app = express()
// ...
// This should be the last middleware
app.use(httpErrors())

See ./test/index.js for more examples.