moving a bunch of packages under pkg (#124)

* moving a bunch of packages under pkg

* fix gen

* fix tst

* oops

* fix test fo real

* parse mx/a

pkg/nameservers/nameservers.go

@@ -0,0 +1,69 @@
+//Package nameservers provides logic for dynamically finding nameservers for a domain, and configuring NS records for them.
+package nameservers
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/StackExchange/dnscontrol/models"
+	"github.com/StackExchange/dnscontrol/providers"
+	"github.com/miekg/dns/dnsutil"
+	"strconv"
+)
+
+//DetermineNameservers will find all nameservers we should use for a domain. It follows the following rules:
+//1. All explicitly defined NAMESERVER records will be used.
+//2. Each DSP declares how many nameservers to use. Default is all. 0 indicates to use none.
+func DetermineNameservers(dc *models.DomainConfig, maxNS int, dsps map[string]providers.DNSServiceProvider) ([]*models.Nameserver, error) {
+	//always take explicit
+	ns := dc.Nameservers
+	for dsp, n := range dc.DNSProviders {
+		if n == 0 {
+			continue
+		}
+		fmt.Printf("----- Getting nameservers from: %s\n", dsp)
+		p, ok := dsps[dsp]
+		if !ok {
+			return nil, fmt.Errorf("DNS provider %s not declared", dsp)
+		}
+		nss, err := p.GetNameservers(dc.Name)
+		if err != nil {
+			return nil, err
+		}
+		take := len(nss)
+		if n > 0 && n < take {
+			take = n
+		}
+		for i := 0; i < take; i++ {
+			ns = append(ns, nss[i])
+		}
+	}
+	return ns, nil
+}
+
+//AddNSRecords creates NS records on a domain corresponding to the nameservers specified.
+func AddNSRecords(dc *models.DomainConfig) {
+	ttl := uint32(300)
+	if ttls, ok := dc.Metadata["ns_ttl"]; ok {
+		t, err := strconv.ParseUint(ttls, 10, 32)
+		if err != nil {
+			fmt.Printf("WARNING: ns_ttl fpr %s (%s) is not a valid int", dc.Name, ttls)
+		} else {
+			ttl = uint32(t)
+		}
+	}
+	for _, ns := range dc.Nameservers {
+		rc := &models.RecordConfig{
+			Type:     "NS",
+			Name:     "@",
+			Target:   ns.Name,
+			Metadata: map[string]string{},
+			TTL:      ttl,
+		}
+		if !strings.HasSuffix(rc.Target, ".") {
+			rc.Target += "."
+		}
+		rc.NameFQDN = dnsutil.AddOrigin(rc.Name, dc.Name)
+		dc.Records = append(dc.Records, rc)
+	}
+}