_usage.ts

const parse = guard(input => JSON.parse(input), {});

/**
  * - Will always be an object
  * - Don't have to clutter with try/catch
  * - Can test if the returned value is default value to know success
  * - In development errors are logged to console and browser notifications sent
  * - In development notifications mesages are cached to not spam developer
  * - In production, errors are sent to error logging service
  */

const data = parse(event.data);

guard.ts

import * as Sentry from '@sentry/browser';
import {last} from 'lodash';
import {StackFrame} from 'stacktrace-js';

function guard(fn, defaultValue) {
  return (...args) => {
    try {
      return fn(...args);
    } catch (error) {
      if (process.env.NODE_ENV === 'production') {
        Sentry.captureException(error);
      } else {
        handleDevelopmentError(error);
      }
      return defaultValue;
    }
  };
}

function parseErrorInfo(error: Error) {
  const errorStackParser = require('error-stack-parser');
  const stackInfo = last<StackFrame>(errorStackParser.parse(error));

  if (!stackInfo) {
    return {
      title: error.message,
      cacheKey: error.message || 'Unknown function name',
    };
  }

  return {
    title:
      stackInfo.functionName ||
      stackInfo.fileName ||
      stackInfo.source ||
      'Unknown function name',
    cacheKey: stackInfo.source || error.message || 'Unknown source',
  };
}

const developmentErrorNotificationCache = {};
function handleDevelopmentError(error: Error) {
  const notifications = require('simple-web-notification');
  const errorInfo = parseErrorInfo(error);

  if (!developmentErrorNotificationCache[errorInfo.cacheKey]) {
    developmentErrorNotificationCache[errorInfo.cacheKey] = true;

    if (console.groupCollapsed) {
      console.groupCollapsed(`caught guarded error (${errorInfo.title})`);
    }

    console.error(error);

    if (console.groupEnd) {
      console.groupEnd();
    }

    notifications.showNotification('Console Error', {
      body: errorInfo.title,
      icon: 'my-icon.ico',
    });
  }
}

export {guard};