provider.go

package inwx

import (
	"context"
	"fmt"
	"strings"
	"sync"
	"time"

	"github.com/libdns/libdns"
)

// Provider facilitates DNS record manipulation with INWX.
type Provider struct {
	// Username of your INWX account.
	Username string `json:"username,omitempty"`

	// Password of your INWX account.
	Password string `json:"password,omitempty"`

	// The shared secret is used to generate a TAN if you have activated "Mobile TAN" for your INWX account.
	SharedSecret string `json:"shared_secret,omitempty"`

	// URL of the JSON-RPC API endpoint. It defaults to the production endpoint.
	EndpointURL string `json:"endpoint_url,omitempty"`

	client   *client
	clientMu sync.Mutex
}

// GetRecords lists all the records in the zone.
func (p *Provider) GetRecords(ctx context.Context, zone string) ([]libdns.Record, error) {
	client, err := p.getClient(ctx)
	defer p.removeClient(ctx)

	if err != nil {
		return nil, err
	}

	inwxRecords, err := client.getRecords(ctx, getDomain(zone))

	if err != nil {
		return nil, err
	}

	results := make([]libdns.Record, 0, len(inwxRecords))

	for _, inwxRecord := range inwxRecords {
		result, err := libdnsRecord(inwxRecord, zone)

		if err != nil {
			return nil, fmt.Errorf("parsing INWX DNS record %+v: %v", inwxRecord, err)
		}

		results = append(results, result)
	}

	return results, nil
}

// AppendRecords adds records to the zone. It returns the records that were added.
func (p *Provider) AppendRecords(ctx context.Context, zone string, records []libdns.Record) ([]libdns.Record, error) {
	client, err := p.getClient(ctx)
	defer p.removeClient(ctx)

	if err != nil {
		return nil, err
	}

	var results []libdns.Record

	for _, record := range records {
		var _, err = client.createRecord(ctx, inwxRecord(record), getDomain(zone))

		if err != nil {
			return nil, err
		}

		results = append(results, record)
	}

	return results, nil
}

// SetRecords sets the records in the zone, either by updating existing records or creating new ones.
// It returns the updated records.
func (p *Provider) SetRecords(ctx context.Context, zone string, records []libdns.Record) ([]libdns.Record, error) {
	client, err := p.getClient(ctx)
	defer p.removeClient(ctx)

	if err != nil {
		return nil, err
	}

	var results []libdns.Record

	for _, record := range records {
		matches, err := p.client.findRecords(ctx, inwxRecord(record), getDomain(zone), false)

		if err != nil {
			return nil, err
		}

		if len(matches) == 0 {
			_, err := client.createRecord(ctx, inwxRecord(record), getDomain(zone))

			if err != nil {
				return nil, err
			}

			results = append(results, record)

			continue
		}

		if len(matches) > 1 {
			return nil, fmt.Errorf("unexpectedly found more than 1 record for %v", record)
		}

		inwxRecord := inwxRecord(record)
		inwxRecord.ID = matches[0].ID

		err = client.updateRecord(ctx, inwxRecord)

		if err != nil {
			return nil, err
		}

		results = append(results, record)

	}

	return results, nil
}

// DeleteRecords deletes the records from the zone. It returns the records that were deleted.
func (p *Provider) DeleteRecords(ctx context.Context, zone string, records []libdns.Record) ([]libdns.Record, error) {
	client, err := p.getClient(ctx)
	defer p.removeClient(ctx)

	if err != nil {
		return nil, err
	}

	var results []libdns.Record

	for _, record := range records {
		exactMatches, err := p.client.findRecords(ctx, inwxRecord(record), getDomain(zone), true)

		if err != nil {
			return nil, err
		}

		for _, inwxRecord := range exactMatches {
			err := client.deleteRecord(ctx, inwxRecord)

			if err != nil {
				return nil, err
			}

			results = append(results, record)
		}
	}

	return results, nil
}

// ListZones lists all zones (nameserver domains) available in the INWX account.
func (p *Provider) ListZones(ctx context.Context) ([]libdns.Zone, error) {
	client, err := p.getClient(ctx)
	defer p.removeClient(ctx)

	if err != nil {
		return nil, err
	}

	domains, err := client.listNameservers(ctx)

	if err != nil {
		return nil, err
	}

	zones := make([]libdns.Zone, 0, len(domains))

	for _, domain := range domains {
		zones = append(zones, libdns.Zone{
			Name: domain.Domain,
		})
	}

	return zones, nil
}

func (p *Provider) getClient(ctx context.Context) (*client, error) {
	p.clientMu.Lock()
	defer p.clientMu.Unlock()

	if p.client == nil {
		client, err := newClient(p.getEndpointURL())
		p.client = client

		if err != nil {
			return nil, err
		}

		err = client.login(ctx, p.Username, p.Password, p.SharedSecret)

		if err != nil {
			return nil, err
		}
	}

	return p.client, nil
}

func (p *Provider) removeClient(ctx context.Context) {
	p.clientMu.Lock()
	defer p.clientMu.Unlock()

	if p.client == nil {
		return
	}

	p.client.logout(ctx)

	p.client = nil
}

func (p *Provider) getEndpointURL() string {
	if p.EndpointURL != "" {
		return p.EndpointURL
	}

	return endpointURL
}

func getDomain(zone string) string {
	return strings.TrimSuffix(zone, ".")
}

func libdnsRecord(record nameserverRecord, zone string) (libdns.Record, error) {
	name := libdns.RelativeName(record.Name, getDomain(zone))
	ttl := time.Duration(record.TTL) * time.Second
	data := record.Content

	if record.Type == "MX" || record.Type == "SRV" {
		data = fmt.Sprintf("%d %s", record.Priority, record.Content)
	}

	return libdns.RR{
		Type: record.Type,
		Name: name,
		Data: data,
		TTL:  ttl,
	}.Parse()
}

func inwxRecord(record libdns.Record) nameserverRecord {
	rr := record.RR()

	inwxRecord := nameserverRecord{
		Name:    rr.Name,
		Type:    rr.Type,
		Content: rr.Data,
		TTL:     int(rr.TTL.Seconds()),
	}

	switch rec := record.(type) {
	case libdns.MX:
		inwxRecord.Content = rec.Target
		inwxRecord.Priority = uint(rec.Preference)
	case libdns.SRV:
		inwxRecord.Content = fmt.Sprintf("%d %d %s", rec.Weight, rec.Port, rec.Target)
		inwxRecord.Priority = uint(rec.Priority)
	}

	return inwxRecord
}

// Interface guards
var (
	_ libdns.RecordGetter   = (*Provider)(nil)
	_ libdns.RecordAppender = (*Provider)(nil)
	_ libdns.RecordSetter   = (*Provider)(nil)
	_ libdns.RecordDeleter  = (*Provider)(nil)
	_ libdns.ZoneLister     = (*Provider)(nil)
)