loader/discover.go

// 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 loader

import (
	"errors"
)

// ErrNoConfiguration is returned when no configuration are found.
var ErrNoConfiguration = errors.New("no configuration found")

// DiscoverFunc is a function that discovers a list of files to load.
type DiscoverFunc func() ([]string, error)

// Discoverer returns a DiscoverFunc that discovers all files that match the given patterns.
func Discoverer(patterns ...string) DiscoverFunc {
	p := make([]string, 0, len(patterns))
	for _, newP := range patterns {
		if len(newP) == 0 {
			continue
		}

		p = append(p, newP)
	}

	if len(p) == 0 {
		return func() ([]string, error) {
			return []string{}, ErrNoConfiguration
		}
	}

	return func() ([]string, error) {
		return DiscoverFiles(p...)
	}
}