a Promise extension that provides filtered catch handler
npm install smart-promiseSmart Promise is a Promise extension that provides filtered catch handler.
[![license][license-img]][license-url]
[![release][release-img]][release-url]
[![semantic][semantic-img]][semantic-url]
[latest results][]
`` text`
bluebird x 3,541 ops/sec ±1.70% (82 runs sampled)
smart-promise x 99,766 ops/sec ±1.24% (86 runs sampled)
` bash`
npm install smart-promise
The same native [Promise API][] applies, the only difference is the catch() method.
Behaves normally as per the native [Promise API][1]
A filtered variant of catch (like other non-JS languages typically have) that lets you only handle specific errors.
The catch handler that is first met that has eligible constructors specified, is the one that will be called.
###### Example
Extend your existing Promise Libraries:
` js
const { Smart } = require('smart-promise')
const Promise = Smart(MyPromiseLib)
// or, use the shorthand
const Promise = require('smart-promise')(MyPromiseLib)
`
Standalone:
` js`
const { Promise } = require('smart-promise')
` js
Promise
.then(_ => return a.b.c.d())
.catch(TypeError, error => {
// If the error is a "TypeError", this code block will execute
})
.catch(ReferenceError, error => {
// If the error is a "ReferenceError", this code block will execute instead
})
.catch('TypedErrorName', error => {
// If the error constructor matches "TypedErrorName", this code block will execute instead
})
.catch(error => {
// Generic catch-the rest (error wasn't TypeError nor ReferenceError)
})
`
You may also add multiple filters for a catch handler:
` js
Promise
.then(_ => return a.b.c.d())
.catch(TypeError, ReferenceError, error => {
// Will end up here on programmer error
})
.catch(NetworkError, TimeoutError, 'SomeError', error => {
// Will end up here on expected everyday network errors
})
.catch(error => {
// Catch any unexpected errors
})
`
You can also wrap it around existing promises resolvers, this is useful for managing 3rd party generated promises:
` js
const { Promise } = require('smart-promise')
const Library = require('some-other-promise-producting-library')
Promise.resolve(Library.action())
.catch('SomeError', error => {})
`
If you're using ESlint or similar tooling, please refer to [prefer-promise-reject-errors][]
[latest results]: https://github.com/ahmadnassri/benchmark-node-promise-catch
[Promise API]: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Promise
[1]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/catch
[prefer-promise-reject-errors`]: https://eslint.org/docs/rules/prefer-promise-reject-errors
----
> Author: Ahmad Nassri •
> Twitter: @AhmadNassri
[license-url]: LICENSE
[license-img]: https://badgen.net/github/license/ahmadnassri/node-smart-promise
[release-url]: https://github.com/ahmadnassri/node-smart-promise/releases
[release-img]: https://badgen.net/github/release/ahmadnassri/node-smart-promise
[semantic-url]: https://github.com/ahmadnassri/node-smart-promise/actions?query=workflow%3Arelease
[semantic-img]: https://badgen.net/badge/📦/semantically%20released/blue