multierror

Documentation

Overview

Package multierror can be leveraged as an opinionated to handle multiple errors providing appropriate wrapping for them.

Index

• type FormatFunc
• type Prefixed
  • func NewPrefixed(prefix string, errs ...error) *Prefixed
  • func (p *Prefixed) Append(errs ...error) *Prefixed
  • func (p *Prefixed) Error() string
  • func (p *Prefixed) ErrorOrNil() error

Examples

• Prefixed

Types

type FormatFunc

type FormatFunc func(es []error) string

FormatFunc defines a format function which should format a slice of errors into a string.

type Prefixed

type Prefixed struct {
	Prefix     string
	Errors     []error
	FormatFunc FormatFunc
}

Prefixed is a multierror which will prefix the error output message with the specified prefix.

Example

// Licensed to Elasticsearch B.V. under one or more contributor
// license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright
// ownership. Elasticsearch B.V. licenses this file to you under
// the Apache License, Version 2.0 (the "License"); you may
// not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

package main

import (
	"errors"
	"fmt"
	"io"
	"os"
)

var output io.Writer = os.Stdout

func main() {
	err := NewPrefixed("config validation")
	err = err.Append(errors.New("some validation error"))

	if err.ErrorOrNil() != nil {
		fmt.Fprintln(output, err)
	}
}

func NewPrefixed

func NewPrefixed(prefix string, errs ...error) *Prefixed

NewPrefixed creates a new pointer to Prefixed w

func (*Prefixed) Append

func (p *Prefixed) Append(errs ...error) *Prefixed

Append appends a number of errors to the current instance of Prefixed. It'll unwrap any wrapped errors in the form of *Prefixed or *multierror.Error.

func (*Prefixed) Error

func (p *Prefixed) Error() string

Error returns the stored slice of error formatted using a set FormatFunc or multierror.ListFormatFunc when no FormatFunc is specified.

func (*Prefixed) ErrorOrNil

func (p *Prefixed) ErrorOrNil() error

ErrorOrNil either returns nil when the type is nil or when there's no Errors. Otherwise, the type is returned.