@homer0/error-handler

💥 Error handler

Listens for uncaught exceptions and unhandled promises rejections, and logs them out with full detail.

By default, if an error is thrown, node will just output the error, but if a Promise is rejected and there's no catch to capture the exception, it will log ..., which doesn't provide a lot of information, right?

Well, ErrorHandler listens for these kind of exceptions, unhandled errors and rejected promises, and logs them with their stack trace information using the Logger utility.

🍿 Usage

⚠️ This package is only for Node.

• ⚙️ Examples
• 🤘 Development

⚙️ Example

import { errorHandler } from '@homer0/error-handler';

const handler = errorHandler();

// ...

handler.listen();

Now, if something like an API call without a catch would throw an error, you'll see the error logged like this:

[2018-01-22 04:19:12] 401
at makeAPICall (/path-to-your-app/index.js:9:42)
at Object.<anonymous> (/path-to-your-app/index.js:11:1)
at Module._compile (module.js:570:32)
at Object.Module._extensions..js (module.js:579:10)
at Module.load (module.js:487:32)
at tryModuleLoad (module.js:446:12)
at Function.Module._load (module.js:438:3)
at Module.runMain (module.js:604:10)
at run (bootstrap_node.js:383:7)
at startup (bootstrap_node.js:149:9)

Date an time, and full stack trace information (with colors!).

Jimple provider

If your app uses a Jimple container, you can register ErrorHandler as the errorHandler service by using its provider:

import { errorHandlerProvider } from '@homer0/error-handler';

// ...

container.register(errorHandlerProvider);

// ...

const handler = container.get('errorHandler');

And since the provider is a "provider creator" (created with my custom version of Jimple), you can customize its service name:

container.register(
  errorHandlerProvider({
    serviceName: 'myErrorHandler',
  }),
);

Dependencies

ErrorHandler depends on the following services, and when used with Jimple, it will try to find them in the container, otherwise, it will create new instances:

• @homer0/simple-logger, with the name appLogger or simpleLogger. Used to generate log the messages in the console.

If you already implement the dependencies, but with a different name, you can specify them in the provider:

container.register(
  errorHandlerProvider({
    services: {
      simpleLogger: 'mySimpleLogger',
      // or `appLogger: 'myAppLogger',`
    },
  }),
);

🤘 Development

As this project is part of the packages monorepo, some of the tooling, like lint-staged and husky, are installed on the root's package.json.

Tasks

Task	Description
lint	Lints the package.
test	Runs the unit tests.
build	Transpiles the project.
types:check	Validates the TypeScript types.