nicolasparada / go-errs

Golang constant error sentinels

Errors

Golang package to create constant sentinel errors.

Install

go get github.com/nicolasparada/go-errs

Usage

You can create your own constant sentinel errors as if they were a string.

package myapp

import (
    errs "github.com/nicolasparada/go-errs"
)

const (
    ErrInvalidEmail = errs.InvalidArgumentError("myapp: invalid email")
)

You can use errors.As to check if your error is of type errs.Error so you can extract the error kind.

package main

import (
    "errors"
    "fmt"

    "myapp"
    errs "github.com/nicolasparada/go-errs"
)

func main() {
    var e errs.Error
    ok := errors.As(myapp.ErrInvalidEmail, &e)
    fmt.Println(ok)
    // Output: true

    ok = e.Kind() == errs.KindInvalidArgument
    fmt.Println(ok)
    // Output: true
}

HTTP Errors

You can use the httperrs subpackage to quickly convert an error defined using this package into an HTTP status code.

package main

import (
    "errors"
    "fmt"

    "myapp"
    "github.com/nicolasparada/go-errs/httperrs"
)

func main() {
    got := httperrs.Code(myapp.ErrInvalidEmail)
    fmt.Println(got)
    // Output: 422
}