config.go

package main

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

type configuration struct {
	Mailserver   string    `json:"mailserver"`
	Mailport     int       `json:"mailport"`
	MailUsername string    `json:"mailusername"`
	MailPassword string    `json:"mailpassword"`
	MailSkipTLS  bool      `json:"mailskiptls"`
	Mailfrom     string    `json:"mailfrom"`
	Mailonerror  bool      `json:"mailonerror"`
	Mailtoerror  string    `json:"mailtoerror"`
	Mailto       string    `json:"mailto"`
	Mailsubject  string    `json:"mailsubject"`
	Timeout      string    `json:"timeout"`
	Keywords     []keyword `json:"keywords"`
	CIDRs        []string  `json:"cidrs"`
}

type keyword struct {
	Keyword    string   `json:"keyword"`
	Exceptions []string `json:"exceptions"`
}

func getConfig(f string) (*configuration, error) {
	if f == "" {
		return nil, fmt.Errorf("please provide a valid config file")
	}

	b, err := os.ReadFile(f) // nolint: gosec
	if err != nil {
		return nil, err
	}
	reader := bytes.NewReader(b)

	decoder := json.NewDecoder(reader)
	decoder.DisallowUnknownFields()
	c := configuration{}
	if err = decoder.Decode(&c); err != nil {
		return nil, err
	}
	return &c, nil
}