jsonify-error

jsonify-error

It's 2018 and neither JSON.stringify(x) nor console.log(x) behave as nicely as they could when x is an error.

With jsonify-error, use jsonifyError(x) instead of x. It produces a plain object with everything one could wish to see about an error.

Installation

For browsers, simply include browser.js in your entry point:

<script src="https://rawgit.com/papb/jsonify-error/1.0.0/browser.js"></script>

In node, as usual, simply do:

npm install --save jsonify-error

Example result

The resulting plain object has the form:

{
    "name": "TypeError",
    "message": "It can't be a string",
    "superclasses": ["Error", "Object"],
    "enumerableFields": {
        // If the error has other fields they appear here (including in the prototype chain):
        "someField": "someValue"
    },
    "stack": [
        "TypeError: It can't be a string", 
        "at z (E:\\test.js:15:15)", 
        "at E:\\test.js:10:9", 
        "at Array.forEach (native)", 
        "at y (E:\\test.js:9:13)", 
        "at x (E:\\test.js:5:5)", 
        "at w (E:\\test.js:24:9)", 
        "at Object.<anonymous> (E:\\test.js:32:1)", 
        "at Module._compile (module.js:570:32)", 
        "at Object.Module._extensions..js (module.js:579:10)", 
        "at Module.load (module.js:487:32)"
    ]
}

Example usage: try-catch

var jsonifyError = require("jsonify-error");

try {
    // ...
} catch (e) {
    console.error(jsonifyError(e));
    process.exit(1);
}

Example usage: promises

For better error logs of unhandled errors in promises, the recommended solution is to use the sibling module, better-promise-error-log. But if you insist, you can do:

var jsonifyError = require("jsonify-error");

somethingAsync().then(() => {
    // ...
}).catch(error => {
    console.error(jsonifyError(e));
    // process.exit(1); // Exiting or not depends on your situation
});

Example usage: with express

var jsonifyError = require("jsonify-error");

app.get('/your/api', (req, res) => {
    // ...
    // Instead of res.status(500).json(error), do:
    res.status(500).json(jsonifyError(error));
});

Example usage: overriding console

require("jsonify-error").overrideConsole();
// Now console.log, console.warn and console.error automatically
// call jsonifyError() on each argument that is instanceof Error
// before logging. Note that overriding native functions/objects
// is usually not a good practice so use this with caution.

Contributing

Any contribution is very welcome. Feel free to open an issue about anything: questions, suggestions, feature requests, bugs, improvements, mistakes, whatever. I will be always looking.

License

MIT - Pedro Augusto de Paula Barbosa

Changelog

1.0.0 - 2018-02-21

• Initial version.