config.go

package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"os"
)

type MailSendConfig struct {
	From string `json:"from"`
	To   string `json:"to"`
}

type MailTemplate struct {
	Subject string `json:"subject"`
	Body    string `json:"body"`
}

type SMTPConfig struct {
	Host     string           `json:"host"`
	Port     string           `json:"port"`
	Username string           `json:"username"`
	Password string           `json:"password"`
	Insecure bool             `json:"insecure"`
	Mails    []MailSendConfig `json:"mails"`
	Template *MailTemplate    `json:"template"`
}

type Config struct {
	BaseURL          string      `json:"baseurl"`
	CertFingerprint  string      `json:"certfingerprint"`
	AuthID           string      `json:"authid"`
	Secret           string      `json:"secret"`
	Datastore        string      `json:"datastore"`
	Namespace        string      `json:"namespace"`
	BackupID         string      `json:"backup-id"`
	BackupSourceDir  string      `json:"backupdir"`
	BackupStreamName string 	 `json:"backupstreamname"`
	PxarOut          string      `json:"pxarout"`
	SMTP             *SMTPConfig `json:"smtp"`
}

func (c *Config) valid() bool {
	baseValid := c.BaseURL != "" && c.AuthID != "" && c.Secret != "" && c.Datastore != "" && ( c.BackupSourceDir != "" || c.BackupStreamName != "" )
	if !baseValid {
		return baseValid
	}

	if c.SMTP != nil {
		mailCfgValid := c.SMTP.Host != "" && c.SMTP.Port != "" && c.SMTP.Username != "" && c.SMTP.Password != ""
		if len(c.SMTP.Mails) == 0 {
			return false
		}
		for i := range c.SMTP.Mails {
			mailCfgValid = mailCfgValid && (c.SMTP.Mails[i].From != "" && c.SMTP.Mails[i].To != "")
		}
		return mailCfgValid
	}

	return true
}

func loadConfig() *Config {
	// Define flags
	baseURLFlag := flag.String("baseurl", "", "Base URL for the proxmox backup server, example: https://192.168.1.10:8007")
	certFingerprintFlag := flag.String("certfingerprint", "", "Certificate fingerprint for SSL connection, example: ea:7d:06:f9...")
	authIDFlag := flag.String("authid", "", "Authentication ID (PBS Api token)")
	secretFlag := flag.String("secret", "", "Secret for authentication")
	datastoreFlag := flag.String("datastore", "", "Datastore name")
	namespaceFlag := flag.String("namespace", "", "Namespace (optional)")
	backupIDFlag := flag.String("backup-id", "", "Backup ID (optional - if not specified, the hostname is used as the default)")
	backupSourceDirFlag := flag.String("backupdir", "", "Backup source directory, must not be symlink")
	backupStreamNameFlag := flag.String("backupstream", "", "Filename for stream backup")
	pxarOutFlag := flag.String("pxarout", "", "Output PXAR archive for debug purposes (optional)")

	mailHostFlag := flag.String("mail-host", "", "mail notification system: mail server host(optional)")
	mailPortFlag := flag.String("mail-port", "", "mail notification system: mail server port(optional)")
	mailUsernameFlag := flag.String("mail-username", "", "mail notification system: mail server username(optional)")
	mailPasswordFlag := flag.String("mail-password", "", "mail notification system: mail server password(optional)")
	mailInsecureFlag := flag.Bool("mail-insecure", false, "mail notification system: allow insecure communications(optional)")
	mailFromFlag := flag.String("mail-from", "", "mail notification system: sender mail(optional)")
	mailToFlag := flag.String("mail-to", "", "mail notification system: receiver mail(optional)")
	mailSubjectTemplateFlag := flag.String("mail-subject-template", "", "mail notification system: mail subject template(optional)")
	mailBodyTemplateFlag := flag.String("mail-body-template", "", "mail notification system: mail body template(optional)")

	configFile := flag.String("config", "", "Path to JSON config file. If this flag is provided all the others will override the loaded config file")

	// Parse command line flags
	flag.Parse()

	config := &Config{}
	if *configFile != "" {
		file, err := os.ReadFile(*configFile)
		if err != nil {
			fmt.Printf("Error reading config file: %v\n", err)
			os.Exit(1)
		}
		err = json.Unmarshal(file, config)
		if err != nil {
			fmt.Printf("Error parsing config file: %v\n", err)
			os.Exit(1)
		}
	}

	if *baseURLFlag != "" {
		config.BaseURL = *baseURLFlag
	}
	if *certFingerprintFlag != "" {
		config.CertFingerprint = *certFingerprintFlag
	}
	if *authIDFlag != "" {
		config.AuthID = *authIDFlag
	}
	if *secretFlag != "" {
		config.Secret = *secretFlag
	}
	if *datastoreFlag != "" {
		config.Datastore = *datastoreFlag
	}
	if *namespaceFlag != "" {
		config.Namespace = *namespaceFlag
	}
	if *backupIDFlag != "" {
		config.BackupID = *backupIDFlag
	}
	if *backupSourceDirFlag != "" {
		config.BackupSourceDir = *backupSourceDirFlag
	}

	if *backupStreamNameFlag != "" {
		config.BackupStreamName = *backupStreamNameFlag
	}
	if *pxarOutFlag != "" {
		config.PxarOut = *pxarOutFlag
	}

	initSmtpConfigIfNeeded := func() {
		if config.SMTP == nil {
			config.SMTP = &SMTPConfig{}
		}
	}
	initMailConfsIfNeeded := func() {
		initSmtpConfigIfNeeded()
		if len(config.SMTP.Mails) == 0 {
			config.SMTP.Mails = append(config.SMTP.Mails, MailSendConfig{})
		}
	}

	if *mailHostFlag != "" {
		initSmtpConfigIfNeeded()
		config.SMTP.Host = *mailHostFlag
	}
	if *mailPortFlag != "" {
		initSmtpConfigIfNeeded()
		config.SMTP.Port = *mailPortFlag
	}
	if *mailUsernameFlag != "" {
		initSmtpConfigIfNeeded()
		config.SMTP.Username = *mailUsernameFlag
	}
	if *mailPasswordFlag != "" {
		initSmtpConfigIfNeeded()
		config.SMTP.Password = *mailPasswordFlag
	}
	if *mailInsecureFlag {
		initSmtpConfigIfNeeded()
		config.SMTP.Insecure = *mailInsecureFlag
	}
	if *mailFromFlag != "" {
		initMailConfsIfNeeded()
		config.SMTP.Mails[0].From = *mailFromFlag
	}
	if *mailToFlag != "" {
		initMailConfsIfNeeded()
		config.SMTP.Mails[0].To = *mailToFlag
	}
	if *mailSubjectTemplateFlag != "" {
		initSmtpConfigIfNeeded()
		config.SMTP.Template.Subject = *mailSubjectTemplateFlag
	}
	if *mailBodyTemplateFlag != "" {
		initSmtpConfigIfNeeded()
		config.SMTP.Template.Body = *mailBodyTemplateFlag
	}

	return config
}