errors

Drop-in replacement for the Go SDK "errors" package with some extra sugar.

Drop-in replacement

This package exports the exact same symbols as exported by the Go SDK standard library errors package, with few additions:

• The New function returns an instance of ErrorWithMeta interface, which extends error with methods for adding tags and labels (see below)
• The Errorf function is added, a proxy to fmt.Errorf but also returns an instance of ErrorwithMeta but with methods for adding tags and labels (see below)
• The Tag and Label structs, used for adding metadata to errors
• The LabelOf function to create a Label instance.
• The HasTag, HasLabel, GetLabel and GetLabels functions for getting an error metadata (if any)

Adding metadata

This package allows adding tags metadata to errors, so that later decisions can be made based on whether a certain error has a certain tag or not (e.g. user-facing, abort, etc).

To add tags metadata to an error, do this:

package myPackage

import "github.com/arikkfir/errors"

func failsWithErrorForTheUser() error {
	return errors.New("an error").WithMeta(errors.Tag("user-facing")) 
}

func failsWithCustomerLabel() error {
	return errors.New("an error").WithMeta(errors.LabelOf("file", "/var/db/bad-file"), errors.LabelOf("customer", "3h18ksk2")) 
}