Cherry pick v1.7 into master

vendor/github.com/xenolf/lego/providers/dns/selectel/selectel.go

@@ -0,0 +1,153 @@
+// Package selectel implements a DNS provider for solving the DNS-01 challenge using Selectel Domains API.
+// Selectel Domain API reference: https://kb.selectel.com/23136054.html
+// Token: https://my.selectel.ru/profile/apikeys
+package selectel
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/xenolf/lego/acme"
+	"github.com/xenolf/lego/platform/config/env"
+)
+
+const (
+	defaultBaseURL = "https://api.selectel.ru/domains/v1"
+	minTTL         = 60
+)
+
+const (
+	envNamespace             = "SELECTEL_"
+	baseURLEnvVar            = envNamespace + "BASE_URL"
+	apiTokenEnvVar           = envNamespace + "API_TOKEN"
+	ttlEnvVar                = envNamespace + "TTL"
+	propagationTimeoutEnvVar = envNamespace + "PROPAGATION_TIMEOUT"
+	pollingIntervalEnvVar    = envNamespace + "POLLING_INTERVAL"
+	httpTimeoutEnvVar        = envNamespace + "HTTP_TIMEOUT"
+)
+
+// Config is used to configure the creation of the DNSProvider.
+type Config struct {
+	BaseURL            string
+	Token              string
+	PropagationTimeout time.Duration
+	PollingInterval    time.Duration
+	TTL                int
+	HTTPClient         *http.Client
+}
+
+// NewDefaultConfig returns a default configuration for the DNSProvider.
+func NewDefaultConfig() *Config {
+	return &Config{
+		BaseURL:            env.GetOrDefaultString(baseURLEnvVar, defaultBaseURL),
+		TTL:                env.GetOrDefaultInt(ttlEnvVar, minTTL),
+		PropagationTimeout: env.GetOrDefaultSecond(propagationTimeoutEnvVar, 120*time.Second),
+		PollingInterval:    env.GetOrDefaultSecond(pollingIntervalEnvVar, 2*time.Second),
+		HTTPClient: &http.Client{
+			Timeout: env.GetOrDefaultSecond(httpTimeoutEnvVar, 30*time.Second),
+		},
+	}
+}
+
+// DNSProvider is an implementation of the acme.ChallengeProvider interface.
+type DNSProvider struct {
+	config *Config
+	client *Client
+}
+
+// NewDNSProvider returns a DNSProvider instance configured for Selectel Domains API.
+// API token must be passed in the environment variable SELECTEL_API_TOKEN.
+func NewDNSProvider() (*DNSProvider, error) {
+	values, err := env.Get(apiTokenEnvVar)
+	if err != nil {
+		return nil, fmt.Errorf("selectel: %v", err)
+	}
+
+	config := NewDefaultConfig()
+	config.Token = values[apiTokenEnvVar]
+
+	return NewDNSProviderConfig(config)
+}
+
+// NewDNSProviderConfig return a DNSProvider instance configured for selectel.
+func NewDNSProviderConfig(config *Config) (*DNSProvider, error) {
+	if config == nil {
+		return nil, errors.New("selectel: the configuration of the DNS provider is nil")
+	}
+
+	if config.Token == "" {
+		return nil, errors.New("selectel: credentials missing")
+	}
+
+	if config.TTL < minTTL {
+		return nil, fmt.Errorf("selectel: invalid TTL, TTL (%d) must be greater than %d", config.TTL, minTTL)
+	}
+
+	client := NewClient(ClientOpts{
+		BaseURL:    config.BaseURL,
+		Token:      config.Token,
+		UserAgent:  acme.UserAgent,
+		HTTPClient: config.HTTPClient,
+	})
+
+	return &DNSProvider{config: config, client: client}, nil
+}
+
+// Timeout returns the Timeout and interval to use when checking for DNS propagation.
+// Adjusting here to cope with spikes in propagation times.
+func (d *DNSProvider) Timeout() (timeout, interval time.Duration) {
+	return d.config.PropagationTimeout, d.config.PollingInterval
+}
+
+// Present creates a TXT record to fulfill DNS-01 challenge.
+func (d *DNSProvider) Present(domain, token, keyAuth string) error {
+	fqdn, value, _ := acme.DNS01Record(domain, keyAuth)
+
+	domainObj, err := d.client.GetDomainByName(domain)
+	if err != nil {
+		return fmt.Errorf("selectel: %v", err)
+	}
+
+	txtRecord := Record{
+		Type:    "TXT",
+		TTL:     d.config.TTL,
+		Name:    fqdn,
+		Content: value,
+	}
+	_, err = d.client.AddRecord(domainObj.ID, txtRecord)
+	if err != nil {
+		return fmt.Errorf("selectel: %v", err)
+	}
+
+	return nil
+}
+
+// CleanUp removes a TXT record used for DNS-01 challenge.
+func (d *DNSProvider) CleanUp(domain, token, keyAuth string) error {
+	fqdn, _, _ := acme.DNS01Record(domain, keyAuth)
+
+	domainObj, err := d.client.GetDomainByName(domain)
+	if err != nil {
+		return fmt.Errorf("selectel: %v", err)
+	}
+
+	records, err := d.client.ListRecords(domainObj.ID)
+	if err != nil {
+		return fmt.Errorf("selectel: %v", err)
+	}
+
+	// Delete records with specific FQDN
+	var lastErr error
+	for _, record := range records {
+		if record.Name == fqdn {
+			err = d.client.DeleteRecord(domainObj.ID, record.ID)
+			if err != nil {
+				lastErr = fmt.Errorf("selectel: %v", err)
+			}
+		}
+	}
+
+	return lastErr
+}