vue-error-boundary

A reusable error boundary component for catching JavaScript errors and displaying fallback UIs.

The ErrorBoundary component is based on React's example component.

Install

yarn add vue-error-boundary

npm i vue-error-boundary --save

For UMD build check out the latest Unpkg link here.

Usage

To use this component simply wrap any other component which may throw an Error. Errors thrown in child components will automatically bubble up to the ErrorBoundary component.

<ErrorBoundary>
  <ImUnstable />
</ErrorBoundary>

Props

Attribute	Description	Type	Required	Default
fall-back	Fallback component to render in case of error.	Component	false	DefaultFallback
on-error	Callback function to perform on error.	Function	false	null
params	Props to pass to your fall back component.	Object	false	{}
stop-propagation	Stop propagation of errors to other errorCaptured hooks.	Boolean	false	false
tag	Wrapper tag used if multiple elements are passed to a slot.	String	false	span

Scoped Slots

Property	Description	Type
err	The error	Error
hasError	Whether an error occurred.	Boolean
info	Information on where the error was captured	String

How to Use

Fallback UI via fall-back

We can provide a fallback UI to display via the fall-back prop. It simply takes a Vue component to render.

Basic Example

<template>
  <ErrorBoundary :fall-back="productError">
    <ProductCard ... />
  </ErrorBoundary>
</template>

<script>
import ProductErrorCard from '...'

export default {
  // ...
  data () {
    return {
      productError: ProductErrorCard
    }
  }
}
</script>

With Props

You can pass props to your fallback component through the params prop. params expects an object containing the data you wish to pass.

<template>
  <ul class="contact-list">
    <template v-for="contact in contacts">
      <error-boundary :key="contact.id" 
                      :fall-back="fallBack" 
                      :params="{ id: contact.id }">
        <app-contact :contact="contact" />
      </error-boundary>
    </template>
  </ul>
</template>

<script>
import MyCustomFallbackComponent from '...'

export default {
  data: () => ({
    fallBack: MyCustomFallbackComponent,
    contacts: [...]
  })
}
</script>

Then in your custom fallback component:

<template>
  <div>
    Could not render - {{ id }}
  </div>
</template>

<script>
export default {
  props: ['id'],
}
</script>

Furthermore, we can directly access the contents of the ErrorBoundary component's errorCaptured hook either throw a callback or Vue's emit.

Scoped Slots

If you do not wish to use a fallback component you can alternatively utilize scoped slots to present data in your current template.

Basic Example

<error-boundary #boundary="{ hasError }">
  <div v-if="!hasError">No error occurred.</div>
  <div v-else>Message to appear if error occurred.</div>
</error-boundary>

Events

Callbacks via on-error

The ErrorBoundary can receive a callback function through the on-error prop.

<template>
  <ErrorBoundary :on-error="handleError">...</ErrorBoundary>
<template>

<script>
// ...
methods: {
  handleError (err, vm, info) {
    // do something
  }
}
// ...
</script>

@errorCaptured event

The callback function will receive the same parameters as the errorCaptured method.

We can also listen to a Vue event via an errorCaptured event.

<template>
  <ErrorBoundary @errorCaptured="handleError">...</ErrorBoundary>
</template>

<script>
// ...
methods: {
  handleError (err, vm, info) {
    // do something
  }
}
// ...
</script>

Stop Propagation

The errorCaptured hook will continue to propagate errors up the component tree unless it returns false. Doing so will stop any additional errorCaptured hooks to execute and the global errorHandler from being invoked for the error. To do this we can use the stop-propagation prop.

<error-boundary stop-propagation>
  ...
</error-boundary>

Contributors

wallyjue