niki/vendor/github.com/go-ozzo/ozzo-validation/error.go

// Copyright 2016 Qiang Xue. All rights reserved.

// Use of this source code is governed by a MIT-style

// license that can be found in the LICENSE file.

package validation

import (
	"encoding/json"
	"fmt"
	"sort"
)

type (

	// Errors represents the validation errors that are indexed by struct field names, map or slice keys.

	Errors map[string]error

	// InternalError represents an error that should NOT be treated as a validation error.

	InternalError interface {
		error

		InternalError() error
	}

	internalError struct {
		error
	}
)

// NewInternalError wraps a given error into an InternalError.

func NewInternalError(err error) InternalError {

	return &internalError{error: err}

}

// InternalError returns the actual error that it wraps around.

func (e *internalError) InternalError() error {

	return e.error

}

// Error returns the error string of Errors.

func (es Errors) Error() string {

	if len(es) == 0 {

		return ""

	}

	keys := []string{}

	for key := range es {

		keys = append(keys, key)

	}

	sort.Strings(keys)

	s := ""

	for i, key := range keys {

		if i > 0 {

			s += "; "

		}

		if errs, ok := es[key].(Errors); ok {

			s += fmt.Sprintf("%v: (%v)", key, errs)

		} else {

			s += fmt.Sprintf("%v: %v", key, es[key].Error())

		}

	}

	return s + "."

}

// MarshalJSON converts the Errors into a valid JSON.

func (es Errors) MarshalJSON() ([]byte, error) {

	errs := map[string]interface{}{}

	for key, err := range es {

		if ms, ok := err.(json.Marshaler); ok {

			errs[key] = ms

		} else {

			errs[key] = err.Error()

		}

	}

	return json.Marshal(errs)

}

// Filter removes all nils from Errors and returns back the updated Errors as an error.

// If the length of Errors becomes 0, it will return nil.

func (es Errors) Filter() error {

	for key, value := range es {

		if value == nil {

			delete(es, key)

		}

	}

	if len(es) == 0 {

		return nil

	}

	return es

}