gostfix/config/config.go

/*
 * MIT License
 *
 * Copyright (c) 2020 Alexey Edelev <semlanik@gmail.com>
 *
 * This file is part of gostfix project https://git.semlanik.org/semlanik/gostfix
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this
 * software and associated documentation files (the "Software"), to deal in the Software
 * without restriction, including without limitation the rights to use, copy, modify,
 * merge, publish, distribute, sublicense, and/or sell copies of the Software, and
 * to permit persons to whom the Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies
 * or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 * PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
 * FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

package config

import (
	"log"
	"strings"
	"sync"

	utils "../utils"
	ini "gopkg.in/go-ini/ini.v1"
)

const configPath = "data/main.ini"

const (
	KeyPostfixConfig = "postfix_config"
)

const (
	PostfixKeyVirtualMailboxMaps    = "virtual_mailbox_maps"
	PostfixKeyVirtualMailboxBase    = "virtual_mailbox_base"
	PostfixKeyVirtualMailboxDomains = "virtual_mailbox_domains"
)

type GostfixConfig gostfixConfig

var (
	once     sync.Once
	instance *gostfixConfig
)

func ConfigInstance() *GostfixConfig {

	once.Do(func() {
		instance, _ = newConfig()
	})

	return (*GostfixConfig)(instance)
}

type gostfixConfig struct {
	VMailboxMaps    string
	VMailboxBase    string
	VMailboxDomains []string
}

func newConfig() (config *gostfixConfig, err error) {

	cfg, err := ini.Load(configPath)
	if err != nil {
		log.Fatalf("Unable to load %s\n", configPath)
		return
	}

	postfixConfigPath := cfg.Section("").Key(KeyPostfixConfig).String()
	if !utils.FileExists(postfixConfigPath) {
		log.Fatalf("Unable to find postfix config %s\n", postfixConfigPath)
		return
	}

	postfixCfg, err := ini.Load(postfixConfigPath)

	if err != nil {
		log.Fatalf("Unable to load %s: %s\n", postfixConfigPath, err)
		return
	}

	baseDir := postfixCfg.Section("").Key(PostfixKeyVirtualMailboxBase).String()

	if !utils.DirectoryExists(baseDir) {
		log.Fatalf("Base dir %s doesn't exist, postfix is not configured proper way, check %s in %s\n", baseDir, PostfixKeyVirtualMailboxBase, postfixConfigPath)
		return
	}

	maps := postfixCfg.Section("").Key(PostfixKeyVirtualMailboxMaps).String()
	mapsList := strings.Split(maps, ":")

	if len(mapsList) != 2 || mapsList[0] != "hash" {
		log.Fatalf("%s is not set proper way in %s. Should be hash:<path/to/virtualmailbox/map>, but %s provided\n", PostfixKeyVirtualMailboxMaps, postfixConfigPath, maps)
		return
	}

	if !utils.FileExists(mapsList[1]) {
		log.Fatalf("Virtual mailbox map %s doesn't exist, postfix is not configured proper way, check %s in %s\n", mapsList[1], PostfixKeyVirtualMailboxMaps, postfixConfigPath)
		return
	}

	domains := postfixCfg.Section("").Key(PostfixKeyVirtualMailboxDomains).String()
	domainsList := strings.Split(domains, " ")
	var validDomains []string
	for _, domain := range domainsList {
		if utils.RegExpUtilsInstance().DomainChecker.MatchString(domain) {
			validDomains = append(validDomains, domain)
		}
	}

	if len(validDomains) < 0 {
		log.Fatalf("Virtual mailbox domains %s are not configured proper way, check %s in %s\n", domains, PostfixKeyVirtualMailboxDomains, postfixConfigPath)
		return
	}

	config = &gostfixConfig{
		VMailboxBase:    baseDir,
		VMailboxMaps:    mapsList[1],
		VMailboxDomains: validDomains,
	}
	return
}