Shieldsbetter Errors
Javascript errors to my particular sensibilities.
TL;DR
const assert = require('assert');
const SbError = require('@shieldsbetter/sberrors2');
class OutOfCheeseError extends SbError {
static messageTemplate = 'Cheese port {{port}} is out of {{cheeseType}}.';
}
const cause = new Error('Cheese delivery late.');
try {
throw new OutOfCheeseError(cause, {
port: 5,
cheeseType: 'gouda',
deployment: 'turkey sandwich'
});
}
catch (e) {
assert.equal(e.message, 'Cheese port 5 is out of gouda.');
assert.equal(e.cause, cause);
assert(e instanceof Error);
assert(e instanceof SbError);
assert(e instanceof OutOfCheeseError);
assert.equal(e.code, 'OUT_OF_CHEESE_ERROR');
assert(e.outOfCheeseError);
assert(e.sbError);
assert.deepEqual(e.details, {
port: 5,
cheeseType: 'gouda',
deployment: 'turkey sandwich'
});
assert.equal(e.port, 5);
assert.equal(e.cheeseType, 'gouda');
assert.equal(e.deployment, 'turkey sandwich');
}Details
Static field messageTemplate will be rendered by the static method
renderMessage, which simply wraps
Mustache.render() by default.
renderMessage() will be called with two arguments:
- The message template
- A details object (which could potentially be
undefinedbut if defined is guaranteed to be an object)
Attempting to instantiate an error without a top-level messageTemplate will
yield an SbError.CannotInstantiateAbstract error.
Non-abstract error types may be instantiated with one or both of an Error cause and a details object, in any order.