NEW PROVIDER: OctoDNS (#309)

* govendor gopkg.in/yaml.v2
* Ignore YAML and BIND test data litter.  Create README.txt files to force git to create subdirectories.
* Update convertzone to also read OctoDNS files

providers/octodns/octodnsProvider.go

@@ -0,0 +1,170 @@
+package octodns
+
+/*
+
+octodns -
+  Generate zonefiles suitiable for OctoDNS.
+
+	The zonefiles are read and written to the directory octoconfig
+
+	If the old octoconfig files are readable, we read them to determine
+	if an update is actually needed.
+
+	The YAML input and output code is extremely complicated because
+	the format does not fit well with a statically typed language.
+	The YAML format changes drastically if the label has single
+	or multiple rtypes associated with it, and if there is a single
+	or multiple rtype data.
+
+*/
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/StackExchange/dnscontrol/models"
+	"github.com/StackExchange/dnscontrol/providers"
+	"github.com/StackExchange/dnscontrol/providers/diff"
+	"github.com/StackExchange/dnscontrol/providers/octodns/octoyaml"
+	"github.com/pkg/errors"
+)
+
+var features = providers.DocumentationNotes{
+	//providers.CanUseCAA: providers.Can(),
+	providers.CanUsePTR: providers.Can(),
+	providers.CanUseSRV: providers.Can(),
+	//providers.CanUseTXTMulti:   providers.Can(),
+	providers.DocCreateDomains: providers.Cannot("Driver just maintains list of OctoDNS config files. You must manually create the master config files that refer these."),
+	providers.DocDualHost:      providers.Cannot("Research is needed."),
+}
+
+func initProvider(config map[string]string, providermeta json.RawMessage) (providers.DNSServiceProvider, error) {
+	// config -- the key/values from creds.json
+	// meta -- the json blob from NewReq('name', 'TYPE', meta)
+	api := &Provider{
+		directory: config["directory"],
+	}
+	if api.directory == "" {
+		api.directory = "config"
+	}
+	if len(providermeta) != 0 {
+		err := json.Unmarshal(providermeta, api)
+		if err != nil {
+			return nil, err
+		}
+	}
+	//api.nameservers = models.StringsToNameservers(api.DefaultNS)
+	return api, nil
+}
+
+func init() {
+	providers.RegisterDomainServiceProviderType("OCTODNS", initProvider, features)
+}
+
+// Provider is the provider handle for the OctoDNS driver.
+type Provider struct {
+	//DefaultNS   []string `json:"default_ns"`
+	//DefaultSoa  SoaInfo  `json:"default_soa"`
+	//nameservers []*models.Nameserver
+	directory string
+}
+
+// GetNameservers returns the nameservers for a domain.
+func (c *Provider) GetNameservers(string) ([]*models.Nameserver, error) {
+	return nil, nil
+}
+
+// GetDomainCorrections returns a list of corrections to update a domain.
+func (c *Provider) GetDomainCorrections(dc *models.DomainConfig) ([]*models.Correction, error) {
+	dc.Punycode()
+	// Phase 1: Copy everything to []*models.RecordConfig:
+	//    expectedRecords < dc.Records[i]
+	//    foundRecords < zonefile
+	//
+	// Phase 2: Do any manipulations:
+	// add NS
+	// manipulate SOA
+	//
+	// Phase 3: Convert to []diff.Records and compare:
+	// expectedDiffRecords < expectedRecords
+	// foundDiffRecords < foundRecords
+	// diff.Inc...(foundDiffRecords, expectedDiffRecords )
+
+	// Read foundRecords:
+	var foundRecords models.Records
+	zoneFileFound := true
+	zoneFileName := filepath.Join(c.directory, strings.Replace(strings.ToLower(dc.Name), "/", "_", -1)+".yaml")
+	foundFH, err := os.Open(zoneFileName)
+	if err != nil {
+		if os.IsNotExist(err) {
+			zoneFileFound = false
+		} else {
+			return nil, errors.Wrapf(err, "can't open %s:", zoneFileName)
+		}
+	} else {
+		foundRecords, err = octoyaml.ReadYaml(foundFH, dc.Name)
+		if err != nil {
+			return nil, errors.Wrapf(err, "can not get corrections")
+		}
+	}
+
+	// Normalize
+	models.PostProcessRecords(foundRecords)
+
+	differ := diff.New(dc)
+	_, create, del, mod := differ.IncrementalDiff(foundRecords)
+
+	buf := &bytes.Buffer{}
+	// Print a list of changes. Generate an actual change that is the zone
+	changes := false
+	for _, i := range create {
+		changes = true
+		fmt.Fprintln(buf, i)
+	}
+	for _, i := range del {
+		changes = true
+		fmt.Fprintln(buf, i)
+	}
+	for _, i := range mod {
+		changes = true
+		fmt.Fprintln(buf, i)
+	}
+	msg := fmt.Sprintf("GENERATE_CONFIGFILE: %s", dc.Name)
+	if zoneFileFound {
+		msg += "\n"
+		msg += buf.String()
+	} else {
+		msg += fmt.Sprintf(" (%d records)\n", len(create))
+	}
+	corrections := []*models.Correction{}
+	if changes {
+		corrections = append(corrections,
+			&models.Correction{
+				Msg: msg,
+				F: func() error {
+					fmt.Printf("CREATING CONFIGFILE: %v\n", zoneFileName)
+					zf, err := os.Create(zoneFileName)
+					if err != nil {
+						log.Fatalf("Could not create zonefile: %v", err)
+					}
+					//err = WriteZoneFile(zf, dc.Records, dc.Name)
+					err = octoyaml.WriteYaml(zf, dc.Records, dc.Name)
+					if err != nil {
+						log.Fatalf("WriteZoneFile error: %v\n", err)
+					}
+					err = zf.Close()
+					if err != nil {
+						log.Fatalf("Closing: %v", err)
+					}
+					return nil
+				},
+			})
+	}
+
+	return corrections, nil
+}