/
duckdns.go
81 lines (69 loc) · 2.39 KB
/
duckdns.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
// Package duckdns Adds lego support for http://duckdns.org .
// See http://www.duckdns.org/spec.jsp for more info on updating TXT records.
package duckdns
import (
"errors"
"fmt"
"io/ioutil"
"os"
"github.com/xenolf/lego/acme"
)
// DNSProvider adds and removes the record for the DNS challenge
type DNSProvider struct {
// The duckdns api token
token string
}
// NewDNSProvider returns a new DNS provider using
// environment variable DUCKDNS_TOKEN for adding and removing the DNS record.
func NewDNSProvider() (*DNSProvider, error) {
duckdnsToken := os.Getenv("DUCKDNS_TOKEN")
return NewDNSProviderCredentials(duckdnsToken)
}
// NewDNSProviderCredentials uses the supplied credentials to return a
// DNSProvider instance configured for http://duckdns.org .
func NewDNSProviderCredentials(duckdnsToken string) (*DNSProvider, error) {
if duckdnsToken == "" {
return nil, errors.New("environment variable DUCKDNS_TOKEN not set")
}
return &DNSProvider{token: duckdnsToken}, nil
}
// makeDuckdnsURL creates a url to clear the set or unset the TXT record.
// txt == "" will clear the TXT record.
func makeDuckdnsURL(domain, token, txt string) string {
requestBase := fmt.Sprintf("https://www.duckdns.org/update?domains=%s&token=%s", domain, token)
if txt == "" {
return requestBase + "&clear=true"
}
return requestBase + "&txt=" + txt
}
func issueDuckdnsRequest(url string) error {
response, err := acme.HTTPClient.Get(url)
if err != nil {
return err
}
defer response.Body.Close()
bodyBytes, err := ioutil.ReadAll(response.Body)
if err != nil {
return err
}
body := string(bodyBytes)
if body != "OK" {
return fmt.Errorf("Request to change TXT record for duckdns returned the following result (%s) this does not match expectation (OK) used url [%s]", body, url)
}
return nil
}
// Present creates a TXT record to fulfil the dns-01 challenge.
// In duckdns you only have one TXT record shared with
// the domain and all sub domains.
//
// To update the TXT record we just need to make one simple get request.
func (d *DNSProvider) Present(domain, token, keyAuth string) error {
_, txtRecord, _ := acme.DNS01Record(domain, keyAuth)
url := makeDuckdnsURL(domain, d.token, txtRecord)
return issueDuckdnsRequest(url)
}
// CleanUp clears duckdns TXT record
func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
url := makeDuckdnsURL(domain, d.token, "")
return issueDuckdnsRequest(url)
}