blink/internal/file/write.go

package file

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

// Supported extensions
var Extensions = []string{"csv", "txt", "json"}

// Write to file
func Write(path, domain, subdomain string, ips []string) error {
	// Store extension
	var extension string

	// Split by extension
	split := strings.Split(path, ".")

	// No extension found
	if len(split) != 2 {
		extension = "txt"
	} else {
		extension = split[1]
	}

	// Open the file
	file, err := os.OpenFile(path, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
	if err != nil {
		return err
	}
	defer file.Close()

	// Check extension
	switch extension {
	case "csv":
		// Store IPs
		ip := strings.Join(ips, "#")

		// Format line
		line := fmt.Sprintf("%s,%s,%s\n", domain, subdomain, ip)

		// Write line
		_, err := file.Write([]byte(line))
		if err != nil {
			return err
		}

	case "txt":
		// Store IPs
		ip := strings.Join(ips, ",")

		// Format line
		line := fmt.Sprintf("%s:%s:%s\n", domain, subdomain, ip)

		// Write line
		_, err := file.Write([]byte(line))
		if err != nil {
			return err
		}

	case "json":
		// Format struct
		output := struct {
			Domain    string   `json:"domain"`
			Subdomain string   `json:"subdomain"`
			Hosts     []string `json:"hosts"`
		}{
			Domain:    domain,
			Subdomain: subdomain,
			Hosts:     ips,
		}

		// Marshal JSON
		jason, err := json.Marshal(&output)
		if err != nil {
			return err
		}

		// Format line
		line := string(jason) + "\n"

		// Write line
		_, err = file.Write([]byte(line))
		if err != nil {
			return err
		}
	}

	return nil
}