lego/providers/dns/dnshomede/internal/client.go
2023-05-05 09:49:38 +02:00

122 lines
2.8 KiB
Go

package internal
import (
"context"
"errors"
"fmt"
"io"
"net/http"
"net/url"
"strings"
"sync"
"time"
"github.com/go-acme/lego/v4/providers/dns/internal/errutils"
)
const (
removeAction = "rm"
addAction = "add"
)
const successCode = "successfully"
const defaultBaseURL = "https://www.dnshome.de/dyndns.php"
// Client the dnsHome.de client.
type Client struct {
baseURL string
HTTPClient *http.Client
credentials map[string]string
credMu sync.Mutex
}
// NewClient Creates a new Client.
func NewClient(credentials map[string]string) *Client {
return &Client{
HTTPClient: &http.Client{Timeout: 10 * time.Second},
baseURL: defaultBaseURL,
credentials: credentials,
}
}
// Add adds a TXT record.
// only one TXT record for ACME is allowed, so it will update the "current" TXT record.
func (c *Client) Add(ctx context.Context, hostname, value string) error {
domain := strings.TrimPrefix(hostname, "_acme-challenge.")
return c.doAction(ctx, domain, addAction, value)
}
// Remove removes a TXT record.
// only one TXT record for ACME is allowed, so it will remove "all" the TXT records.
func (c *Client) Remove(ctx context.Context, hostname, value string) error {
domain := strings.TrimPrefix(hostname, "_acme-challenge.")
return c.doAction(ctx, domain, removeAction, value)
}
func (c *Client) doAction(ctx context.Context, domain, action, value string) error {
endpoint, err := c.createEndpoint(domain, action, value)
if err != nil {
return err
}
req, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint.String(), http.NoBody)
if err != nil {
return fmt.Errorf("unable to create request: %w", err)
}
resp, err := c.HTTPClient.Do(req)
if err != nil {
return errutils.NewHTTPDoError(req, err)
}
defer func() { _ = resp.Body.Close() }()
if resp.StatusCode != http.StatusOK {
return errutils.NewUnexpectedResponseStatusCodeError(req, resp)
}
raw, err := io.ReadAll(resp.Body)
if err != nil {
return errutils.NewReadResponseError(req, resp.StatusCode, err)
}
output := string(raw)
if !strings.HasPrefix(output, successCode) {
return errors.New(output)
}
return nil
}
func (c *Client) createEndpoint(domain, action, value string) (*url.URL, error) {
if len(value) < 12 {
return nil, fmt.Errorf("the TXT value must have more than 12 characters: %s", value)
}
endpoint, err := url.Parse(c.baseURL)
if err != nil {
return nil, err
}
c.credMu.Lock()
password, ok := c.credentials[domain]
c.credMu.Unlock()
if !ok {
return nil, fmt.Errorf("domain %s not found in credentials, check your credentials map", domain)
}
endpoint.User = url.UserPassword(domain, password)
query := endpoint.Query()
query.Set("acme", action)
query.Set("txt", value)
endpoint.RawQuery = query.Encode()
return endpoint, nil
}