env.go

/*
Copyright 2015 The Kubernetes Authors.

Licensed 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 env

import (
	"os"
	"strconv"
	"strings"
)

// GetEnvAsStringOrFallback returns the env variable for the given key
// and falls back to the given defaultValue if not set
func GetEnvAsStringOrFallback(key, defaultValue string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return defaultValue
}

// GetEnvAsArrayOfStringsOrFallback returns the env variable for the given key
// and falls back to the given defaultValue if not set
// GetEnvAsArrayOfStringsOrFallback trims all whitespaces from input i.e. "us, fr, au" -> {"us","fr","au"}
func GetEnvAsArrayOfStringsOrFallback(key string, defaultValue []string) []string {
	v := GetEnvAsStringOrFallback(key, "")
	if v != "" {
		arr := strings.Split(strings.ReplaceAll(v, " ", ""), ",")
		if len(arr) != 0 {
			return arr
		}
	}
	return defaultValue
}

// GetEnvAsIntOrFallback returns the env variable (parsed as integer) for
// the given key and falls back to the given defaultValue if not set
func GetEnvAsIntOrFallback(key string, defaultValue int) (int, error) {
	if v := os.Getenv(key); v != "" {
		value, err := strconv.Atoi(v)
		if err != nil {
			return defaultValue, err
		}
		return value, nil
	}
	return defaultValue, nil
}

// GetEnvAsFloat64OrFallback returns the env variable (parsed as float64) for
// the given key and falls back to the given defaultValue if not set
func GetEnvAsFloat64OrFallback(key string, defaultValue float64) (float64, error) {
	if v := os.Getenv(key); v != "" {
		value, err := strconv.ParseFloat(v, 64)
		if err != nil {
			return defaultValue, err
		}
		return value, nil
	}
	return defaultValue, nil
}

// GetEnvAsBoolOrFallback returns the env variable for the given key,
// parses it as boolean and falls back to the given defaultValue if not set
func GetEnvAsBoolOrFallback(key string, defaultValue bool) bool {
	if v := os.Getenv(key); v != "" {
		val, err := strconv.ParseBool(v)
		if err != nil {
			return defaultValue
		}
		return val
	}
	return defaultValue
}