ember-exception-handling

This addon provides utilities related to exception handling for Ember applications.

Installation

ember install ember-exception-handling

Usage

While some errors in JavaScript applications are typed, and specific types of Errors can be evaluated for, most errors are simply utilizing the Error class. As such, the same exception handling semantics aren't as readily available to JavaScript engineers.

While the above is true, it's still possible to make use of patterns that help evaluate whether a certain kind of error has been throw. To do this, we employ pattern matching, which allows us flexibility to introspect errors and error properties to determine how to handle each exception.

This addon comes with a few useful types and utilities.

PatterMatcher Class

PatternMatcher is a class used to specify an error pattern to match. The PatternMatcher constructor takes the following forms:

constructor(error, Function)

import PatternMatcher from 'exception-handling/utils/pattern-matcher';

const error = new Error('test');
const matcher = new PatternMatcher(error, function(errorToMatch) {
  return errorToMatch && errorToMatch.message === 'test';
});

const isMatch = matcher.match(); // true

constructor(error, Object);

import PatternMatcher from 'exception-handling/utils/pattern-matcher';

const error = new Error('test');
const matcher = new PatternMatcher(error, { message: 'test' });
});

const isMatch = matcher.match(); // true

match Utility

TL;DR use when you want to match certain patterns within an error, and rethrow anything not matched.

import match from 'exception-handling/utils/match';

getResource().catch(
  match({
    matcher: { message: 'test' },

    onMatch(e) {
      return [];
    },
  })
);

retry Utility

TL;DR use when you want to retry if a certain pattern is matched, and rethrow anything not matched.

import retry from 'exception-handling/utils/retry';
import { resolve } from 'rsvp';

getResource().catch(
  retry({
    matcher: { message: 'test' },

    onRetry() {
      return resolve('resolved');
    },
  })
);

Contributing

Installation

• git clone https://github.com/ember-exception-handling/ember-exception-handling.git
• cd ember-exception-handling
• npm install

Linting

• npm run lint:hbs
• npm run lint:js
• npm run lint:js -- --fix

Running tests

• ember test – Runs the test suite on the current Ember version
• ember test --server – Runs the test suite in "watch mode"
• ember try:each – Runs the test suite against multiple Ember versions

Running the dummy application

• ember serve
• Visit the dummy application at http://localhost:4200.

For more information on using ember-cli, visit https://ember-cli.com/.

License

This project is licensed under the MIT License.