@stayradiated/error-boundary

Stop throwing errors, try passing them as values instead.

An Error Boundary guarantees to return any caught exceptions to make it easier to reason about your code.

Shout out to @brendonjohn for introducing me to this function.

Installation

npm install --save @stayradiated/error-boundary

API

• errorBoundary<T>(fn: () => Promise<T|Error>): Promise<T|Error>
• errorBoundarySync<T>(fn: () => T|Error): T|Error
• errorListBoundary<T>(fn: () => Promise<Array<T|Error>>): Promise<T[]|Error>
• errorListBoundarySync<T>(fn: () => Array<T|Error>): T[]|Error
• assertOk<T>(value: T | Error): asserts value is T extends Error ? never : T
• assertError<T>(value: T | Error, errorMessage?: string): asserts value is Error

Usage

const { errorBoundarySync } = await import('@stayradiated/error-boundary')

const mayThrow = () => {
  if (Math.random() > 0.5) {
    throw new Error('Woah, something broke!')
  } else {
    return 'All good here!'
  }
}

const valueOrError = errorBoundarySync(() => mayThrow())

if (valueOrError instanceof Error) {
  // explicititly handle error
  console.error(valueOrError)
} else{
  // handle result
  console.log(valueOrError)
}

const { errorListBoundary } = await import('@stayradiated/error-boundary')

const results = await errorListBoundary(Promise.all(
  jobs.map(async (item) => {
    return runJob(item)
  })
))
if (results instanceof Error) {
  const error = results
  logError(error)
  return
}

MIT License

Copyright © 2021 George Czabania

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.