New provider: Linode (#268)

OWNERS

@@ -5,6 +5,7 @@ providers/digitalocean @Deraen
 providers/dnsimple @aeden
 providers/gandi @TomOnTime
 # providers/gcloud
+providers/linode @koesie10
 providers/namecheap @captncraig
 # providers/namedotcom
 providers/ns1 @captncraig

README.md

@@ -20,6 +20,7 @@ Currently supported DNS providers:
  - DNSimple
  - Gandi
  - Google
+ - Linode
  - Namecheap
  - Name.com
  - NS1

docs/_includes/matrix.html

@@ -13,6 +13,7 @@
 	<th class="rotate"><div><span>DNSIMPLE</span></div></th>
 	<th class="rotate"><div><span>GANDI</span></div></th>
 	<th class="rotate"><div><span>GCLOUD</span></div></th>
+	<th class="rotate"><div><span>LINODE</span></div></th>
 	<th class="rotate"><div><span>NAMECHEAP</span></div></th>
 	<th class="rotate"><div><span>NAMEDOTCOM</span></div></th>
 	<th class="rotate"><div><span>NS1</span></div></th>
@@ -49,6 +50,9 @@
 		<td class="danger">
 			<i class="fa fa-times text-danger" aria-hidden="true"></i>
 		</td>
+		<td class="danger">
+			<i class="fa fa-times text-danger" aria-hidden="true"></i>
+		</td>
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
@@ -91,6 +95,9 @@
 		<td class="danger">
 			<i class="fa fa-times text-danger" aria-hidden="true"></i>
 		</td>
+		<td class="danger">
+			<i class="fa fa-times text-danger" aria-hidden="true"></i>
+		</td>
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
@@ -157,6 +164,9 @@
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
+		<td class="success">
+			<i class="fa fa-check text-success" aria-hidden="true"></i>
+		</td>
 		</tr>
 	<tr>
 		<th class="row-header" style="text-decoration: underline;" data-toggle="tooltip" data-container="body" data-placement="top" title="Provider supports some kind of ALIAS, ANAME or flattened CNAME record type">ALIAS</th>
@@ -173,6 +183,7 @@
 		</td>
 		<td><i class="fa fa-minus dim"></i></td>
 		<td><i class="fa fa-minus dim"></i></td>
+		<td><i class="fa fa-minus dim"></i></td>
 		<td class="danger">
 			<i class="fa fa-times text-danger" aria-hidden="true"></i>
 		</td>
@@ -214,6 +225,7 @@
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
+		<td><i class="fa fa-minus dim"></i></td>
 		<td class="danger" data-toggle="tooltip" data-container="body" data-placement="top" title="The namecheap web console allows you to make SRV records, but their api does not let you read or set them">
 			<i class="fa has-tooltip fa-times text-danger" aria-hidden="true"></i>
 		</td>
@@ -253,6 +265,7 @@
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
+		<td><i class="fa fa-minus dim"></i></td>
 		<td class="danger">
 			<i class="fa fa-times text-danger" aria-hidden="true"></i>
 		</td>
@@ -288,6 +301,7 @@
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
+		<td><i class="fa fa-minus dim"></i></td>
 		<td class="danger">
 			<i class="fa fa-times text-danger" aria-hidden="true"></i>
 		</td>
@@ -317,6 +331,7 @@
 		</td>
 		<td><i class="fa fa-minus dim"></i></td>
 		<td><i class="fa fa-minus dim"></i></td>
+		<td><i class="fa fa-minus dim"></i></td>
 		<td class="danger">
 			<i class="fa fa-times text-danger" aria-hidden="true"></i>
 		</td>
@@ -350,6 +365,9 @@
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
+		<td class="danger">
+			<i class="fa fa-times text-danger" aria-hidden="true"></i>
+		</td>
 		<td class="danger" data-toggle="tooltip" data-container="body" data-placement="top" title="Doesn&#39;t allow control of apex NS records">
 			<i class="fa has-tooltip fa-times text-danger" aria-hidden="true"></i>
 		</td>
@@ -391,6 +409,9 @@
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
+		<td class="danger">
+			<i class="fa fa-times text-danger" aria-hidden="true"></i>
+		</td>
 		<td class="danger" data-toggle="tooltip" data-container="body" data-placement="top" title="Requires domain registered through their service">
 			<i class="fa has-tooltip fa-times text-danger" aria-hidden="true"></i>
 		</td>
@@ -436,6 +457,9 @@
 		<td class="success">
 			<i class="fa fa-check text-success" aria-hidden="true"></i>
 		</td>
+		<td class="success">
+			<i class="fa fa-check text-success" aria-hidden="true"></i>
+		</td>
 		<td class="danger">
 			<i class="fa fa-times text-danger" aria-hidden="true"></i>
 		</td>

docs/_providers/linode.md

@@ -0,0 +1,57 @@
+---
+name: Linode
+title: Linode Provider
+layout: default
+jsId: LINODE
+---
+# Linode Provider
+
+## Configuration
+In your credentials file, you must provide your
+[Linode Personal Access Token](https://cloud.linode.com/profile/tokens)
+
+{% highlight json %}
+{
+  "linode": {
+    "token": "your-linode-personal-access-token"
+  }
+}
+{% endhighlight %}
+
+## Metadata
+This provider does not recognize any special metadata fields unique to Linode.
+
+## Usage
+Example Javascript:
+
+{% highlight js %}
+var REG_NONE = NewRegistrar('none', 'NONE')
+var LINODE = NewDnsProvider("linode", "LINODE");
+
+D("example.tld", REG_NONE, DnsProvider(LINODE),
+    A("test","1.2.3.4")
+);
+{%endhighlight%}
+
+## Activation
+[Create Personal Access Token](https://cloud.linode.com/profile/tokens)
+
+## Caveats
+Linode does not allow all TTLs, but only a specific subset of TTLs. The following TTLs are supported
+([source](https://github.com/linode/manager/blob/master/src/domains/components/SelectDNSSeconds.js)):
+
+- 300
+- 3600
+- 7200
+- 14400
+- 28800
+- 57600
+- 86400
+- 172800
+- 345600
+- 604800
+- 1209600
+- 2419200
+
+The provider will automatically round up your TTL to one of these values. For example, 600 seconds would become 3600
+seconds, but 300 seconds would stay 300 seconds. 

docs/provider-list.md

@@ -63,6 +63,7 @@ Maintainers of contributed providers:
 * digital ocean @Deraen
 * dnsimple @aeden
 * gandi @TomOnTime
+* Linode @koesie10
 * namecheap @captncraig
 * ns1 @captncraig
 * OVH @masterzen
@@ -83,7 +84,6 @@ code to support this provider, please re-open the issue. We'd be glad to help in
   <li>GoDaddy (<a href="https://github.com/StackExchange/dnscontrol/issues/145">#145</a>)</li>
   <li>Hurricane Electric (dns.he.net) (<a href="https://github.com/StackExchange/dnscontrol/issues/118">#118</a>)</li>
   <li>INWX (<a href="https://github.com/StackExchange/dnscontrol/issues/254">#254</a>)</li>
-  <li>Linode (<a href="https://github.com/StackExchange/dnscontrol/issues/121">#121</a>)</li>
   <li>NameSilo (<a href="https://github.com/StackExchange/dnscontrol/issues/220">#220</a>)</li>
   <li>OVH (<a href="https://github.com/StackExchange/dnscontrol/issues/143">#143</a>)</li>
 </ul>

integrationTest/providers.json

@@ -36,6 +36,12 @@
     "private_key": "$GCLOUD_PRIVATEKEY",
     "project_id": "$GCLOUD_PROJECT"
   },
+  "LINODE": {
+    "COMMENT": "25: Linode's hostname validation does not allow the target domain TLD",
+    "token": "$LINODE_TOKEN",
+    "domain": "$LINODE_DOMAIN",
+    "knownFailures": "25"
+  },
   "NS1": {
     "domain": "$NS1_DOMAIN",
     "api_token": "$NS1_TOKEN"

providers/_all/all.go

@@ -10,6 +10,7 @@ import (
 	_ "github.com/StackExchange/dnscontrol/providers/dnsimple"
 	_ "github.com/StackExchange/dnscontrol/providers/gandi"
 	_ "github.com/StackExchange/dnscontrol/providers/gcloud"
+	_ "github.com/StackExchange/dnscontrol/providers/linode"
 	_ "github.com/StackExchange/dnscontrol/providers/namecheap"
 	_ "github.com/StackExchange/dnscontrol/providers/namedotcom"
 	_ "github.com/StackExchange/dnscontrol/providers/ns1"

providers/linode/api.go

@@ -0,0 +1,245 @@
+package linode
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+)
+
+const (
+	mediaType      = "application/json"
+	defaultBaseURL = "https://api.linode.com/v4/"
+	domainsPath    = "domains"
+)
+
+func (c *LinodeApi) fetchDomainList() error {
+	c.domainIndex = map[string]int{}
+	page := 1
+	for {
+		dr := &domainResponse{}
+		endpoint := fmt.Sprintf("%s?page=%d", domainsPath, page)
+		if err := c.get(endpoint, dr); err != nil {
+			return fmt.Errorf("Error fetching domain list from Linode: %s", err)
+		}
+		for _, domain := range dr.Data {
+			c.domainIndex[domain.Domain] = domain.ID
+		}
+		if len(dr.Data) == 0 || dr.Page >= dr.Pages {
+			break
+		}
+		page++
+	}
+	return nil
+}
+
+func (c *LinodeApi) getRecords(id int) ([]domainRecord, error) {
+	records := []domainRecord{}
+	page := 1
+	for {
+		dr := &recordResponse{}
+		endpoint := fmt.Sprintf("%s/%d/records?page=%d", domainsPath, id, page)
+		if err := c.get(endpoint, dr); err != nil {
+			return nil, fmt.Errorf("Error fetching record list from Linode: %s", err)
+		}
+
+		records = append(records, dr.Data...)
+
+		if len(dr.Data) == 0 || dr.Page >= dr.Pages {
+			break
+		}
+		page++
+	}
+
+	return records, nil
+}
+
+func (c *LinodeApi) createRecord(domainID int, rec *recordEditRequest) (*domainRecord, error) {
+	endpoint := fmt.Sprintf("%s/%d/records", domainsPath, domainID)
+
+	req, err := c.newRequest(http.MethodPost, endpoint, rec)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := c.client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, c.handleErrors(resp)
+	}
+
+	record := &domainRecord{}
+
+	defer resp.Body.Close()
+	decoder := json.NewDecoder(resp.Body)
+	if err := decoder.Decode(record); err != nil {
+		return nil, err
+	}
+
+	return record, nil
+}
+
+func (c *LinodeApi) modifyRecord(domainID, recordID int, rec *recordEditRequest) error {
+	endpoint := fmt.Sprintf("%s/%d/records/%d", domainsPath, domainID, recordID)
+
+	req, err := c.newRequest(http.MethodPut, endpoint, rec)
+	if err != nil {
+		return err
+	}
+
+	resp, err := c.client.Do(req)
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return c.handleErrors(resp)
+	}
+
+	return nil
+}
+
+func (c *LinodeApi) deleteRecord(domainID, recordID int) error {
+	endpoint := fmt.Sprintf("%s/%d/records/%d", domainsPath, domainID, recordID)
+	req, err := c.newRequest(http.MethodDelete, endpoint, nil)
+	if err != nil {
+		return err
+	}
+
+	resp, err := c.client.Do(req)
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return c.handleErrors(resp)
+	}
+
+	return nil
+}
+
+func (c *LinodeApi) newRequest(method, endpoint string, body interface{}) (*http.Request, error) {
+	rel, err := url.Parse(endpoint)
+	if err != nil {
+		return nil, err
+	}
+
+	u := c.baseURL.ResolveReference(rel)
+
+	buf := new(bytes.Buffer)
+	if body != nil {
+		err = json.NewEncoder(buf).Encode(body)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	req, err := http.NewRequest(method, u.String(), buf)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Add("Content-Type", mediaType)
+	req.Header.Add("Accept", mediaType)
+	return req, nil
+}
+
+func (c *LinodeApi) get(endpoint string, target interface{}) error {
+	req, err := c.newRequest(http.MethodGet, endpoint, nil)
+	if err != nil {
+		return err
+	}
+	resp, err := c.client.Do(req)
+	if err != nil {
+		return err
+	}
+	if resp.StatusCode != http.StatusOK {
+		return c.handleErrors(resp)
+	}
+	defer resp.Body.Close()
+	decoder := json.NewDecoder(resp.Body)
+	return decoder.Decode(target)
+}
+
+func (c *LinodeApi) handleErrors(resp *http.Response) error {
+	defer resp.Body.Close()
+	decoder := json.NewDecoder(resp.Body)
+
+	errs := &errorResponse{}
+
+	if err := decoder.Decode(errs); err != nil {
+		return fmt.Errorf("Bad status code from Linode: %d not 200. Failed to decode response.", resp.StatusCode)
+	}
+
+	buf := bytes.NewBufferString(fmt.Sprintf("Bad status code from Linode: %d not 200.", resp.StatusCode))
+
+	for _, err := range errs.Errors {
+		buf.WriteString("\n- ")
+
+		if err.Field != "" {
+			buf.WriteString(err.Field)
+			buf.WriteString(": ")
+		}
+
+		buf.WriteString(err.Reason)
+	}
+
+	return errors.New(buf.String())
+}
+
+type basicResponse struct {
+	Results int `json:"results"`
+	Pages   int `json:"pages"`
+	Page    int `json:"page"`
+}
+
+type domainResponse struct {
+	basicResponse
+	Data []struct {
+		ID     int    `json:"id"`
+		Domain string `json:"domain"`
+	} `json:"data"`
+}
+
+type recordResponse struct {
+	basicResponse
+	Data []domainRecord `json:"data"`
+}
+
+type domainRecord struct {
+	ID       int    `json:"id"`
+	Type     string `json:"type"`
+	Name     string `json:"name"`
+	Target   string `json:"target"`
+	Priority uint16 `json:"priority"`
+	Weight   uint16 `json:"weight"`
+	Port     uint16 `json:"port"`
+	Service  string `json:"service"`
+	Protocol string `json:"protocol"`
+	TTLSec   uint32 `json:"ttl_sec"`
+}
+
+type recordEditRequest struct {
+	Type     string `json:"type,omitempty"`
+	Name     string `json:"name,omitempty"`
+	Target   string `json:"target,omitempty"`
+	Priority int    `json:"priority,omitempty"`
+	Weight   int    `json:"weight,omitempty"`
+	Port     int    `json:"port,omitempty"`
+	Service  string `json:"service,omitempty"`
+	Protocol string `json:"protocol,omitempty"`
+	// Documented as field `ttl` in the documentation, but in reality `ttl_sec` should be used
+	TTL int `json:"ttl_sec,omitempty"`
+}
+
+type errorResponse struct {
+	Errors []struct {
+		Field  string `json:"field"`
+		Reason string `json:"reason"`
+	} `json:"errors"`
+}

providers/linode/linodeProvider.go

@@ -0,0 +1,313 @@
+package linode
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"github.com/StackExchange/dnscontrol/models"
+	"github.com/StackExchange/dnscontrol/providers"
+	"github.com/StackExchange/dnscontrol/providers/diff"
+	"github.com/miekg/dns/dnsutil"
+
+	"net/url"
+
+	"golang.org/x/oauth2"
+	"regexp"
+	"strings"
+)
+
+/*
+
+Linode API DNS provider:
+
+Info required in `creds.json`:
+   - token
+
+*/
+
+var allowedTTLValues = []uint32{
+	300,     // 5 minutes
+	3600,    // 1 hour
+	7200,    // 2 hours
+	14400,   // 4 hours
+	28800,   // 8 hours
+	57600,   // 16 hours
+	86400,   // 1 day
+	172800,  // 2 days
+	345600,  // 4 days
+	604800,  // 1 week
+	1209600, // 2 weeks
+	2419200, // 4 weeks
+}
+
+var srvRegexp = regexp.MustCompile(`^_(?P<Service>\w+)\.\_(?P<Protocol>\w+)$`)
+
+type LinodeApi struct {
+	client      *http.Client
+	baseURL     *url.URL
+	domainIndex map[string]int
+}
+
+var defaultNameServerNames = []string{
+	"ns1.linode.com",
+	"ns2.linode.com",
+	"ns3.linode.com",
+	"ns4.linode.com",
+	"ns5.linode.com",
+}
+
+func NewLinode(m map[string]string, metadata json.RawMessage) (providers.DNSServiceProvider, error) {
+	if m["token"] == "" {
+		return nil, fmt.Errorf("Linode Token must be provided.")
+	}
+
+	ctx := context.Background()
+	client := oauth2.NewClient(
+		ctx,
+		oauth2.StaticTokenSource(&oauth2.Token{AccessToken: m["token"]}),
+	)
+
+	baseURL, err := url.Parse(defaultBaseURL)
+	if err != nil {
+		return nil, fmt.Errorf("Linode base URL not valid")
+	}
+
+	api := &LinodeApi{client: client, baseURL: baseURL}
+
+	// Get a domain to validate the token
+	if err := api.fetchDomainList(); err != nil {
+		return nil, err
+	}
+
+	return api, nil
+}
+
+var docNotes = providers.DocumentationNotes{
+	providers.DocOfficiallySupported: providers.Cannot(),
+	providers.DocDualHost:            providers.Cannot(),
+}
+
+func init() {
+	// SRV support is in this provider, but Linode doesn't seem to support it properly
+	providers.RegisterDomainServiceProviderType("LINODE", NewLinode, docNotes)
+}
+
+func (api *LinodeApi) GetNameservers(domain string) ([]*models.Nameserver, error) {
+	return models.StringsToNameservers(defaultNameServerNames), nil
+}
+
+func (api *LinodeApi) GetDomainCorrections(dc *models.DomainConfig) ([]*models.Correction, error) {
+	dc, err := dc.Copy()
+	if err != nil {
+		return nil, err
+	}
+
+	dc.Punycode()
+
+	if api.domainIndex == nil {
+		if err := api.fetchDomainList(); err != nil {
+			return nil, err
+		}
+	}
+	domainID, ok := api.domainIndex[dc.Name]
+	if !ok {
+		return nil, fmt.Errorf("%s not listed in domains for Linode account", dc.Name)
+	}
+
+	records, err := api.getRecords(domainID)
+	if err != nil {
+		return nil, err
+	}
+
+	existingRecords := make([]*models.RecordConfig, len(records), len(records)+len(defaultNameServerNames))
+	for i := range records {
+		existingRecords[i] = toRc(dc, &records[i])
+	}
+
+	// Linode always has read-only NS servers, but these are not mentioned in the API response
+	// https://github.com/linode/manager/blob/edd99dc4e1be5ab8190f243c3dbf8b830716255e/src/constants.js#L184
+	for _, name := range defaultNameServerNames {
+		existingRecords = append(existingRecords, &models.RecordConfig{
+			NameFQDN: dc.Name,
+			Type:     "NS",
+			Target:   name,
+			Original: &domainRecord{},
+		})
+	}
+
+	// Normalize
+	models.Downcase(existingRecords)
+
+	// Linode doesn't allow selecting an arbitrary TTL, only a set of predefined values
+	// We need to make sure we don't change it every time if it is as close as it's going to get
+	// By experimentation, Linode always rounds up. 300 -> 300, 301 -> 3600.
+	// https://github.com/linode/manager/blob/edd99dc4e1be5ab8190f243c3dbf8b830716255e/src/domains/components/SelectDNSSeconds.js#L19
+	for _, record := range dc.Records {
+		record.TTL = fixTTL(record.TTL)
+	}
+
+	differ := diff.New(dc)
+	_, create, del, modify := differ.IncrementalDiff(existingRecords)
+
+	var corrections []*models.Correction
+
+	// Deletes first so changing type works etc.
+	for _, m := range del {
+		id := m.Existing.Original.(*domainRecord).ID
+		if id == 0 { // Skip ID 0, these are the default nameservers always present
+			continue
+		}
+		corr := &models.Correction{
+			Msg: fmt.Sprintf("%s, Linode ID: %d", m.String(), id),
+			F: func() error {
+				return api.deleteRecord(domainID, id)
+			},
+		}
+		corrections = append(corrections, corr)
+	}
+	for _, m := range create {
+		req, err := toReq(dc, m.Desired)
+		if err != nil {
+			return nil, err
+		}
+		j, err := json.Marshal(req)
+		if err != nil {
+			return nil, err
+		}
+		corr := &models.Correction{
+			Msg: fmt.Sprintf("%s: %s", m.String(), string(j)),
+			F: func() error {
+				record, err := api.createRecord(domainID, req)
+				if err != nil {
+					return err
+				}
+				// TTL isn't saved when creating a record, so we will need to modify it immediately afterwards
+				return api.modifyRecord(domainID, record.ID, req)
+			},
+		}
+		corrections = append(corrections, corr)
+	}
+	for _, m := range modify {
+		id := m.Existing.Original.(*domainRecord).ID
+		if id == 0 { // Skip ID 0, these are the default nameservers always present
+			continue
+		}
+		req, err := toReq(dc, m.Desired)
+		if err != nil {
+			return nil, err
+		}
+		j, err := json.Marshal(req)
+		if err != nil {
+			return nil, err
+		}
+		corr := &models.Correction{
+			Msg: fmt.Sprintf("%s, Linode ID: %d: %s", m.String(), id, string(j)),
+			F: func() error {
+				return api.modifyRecord(domainID, id, req)
+			},
+		}
+		corrections = append(corrections, corr)
+	}
+
+	return corrections, nil
+}
+
+func toRc(dc *models.DomainConfig, r *domainRecord) *models.RecordConfig {
+	// This handles "@" etc.
+	name := dnsutil.AddOrigin(r.Name, dc.Name)
+
+	target := r.Target
+	// Make target FQDN (#rtype_variations)
+	if r.Type == "CNAME" || r.Type == "MX" || r.Type == "NS" || r.Type == "SRV" {
+		target = dnsutil.AddOrigin(target+".", dc.Name)
+	}
+
+	return &models.RecordConfig{
+		NameFQDN:     name,
+		Type:         r.Type,
+		Target:       target,
+		TTL:          r.TTLSec,
+		MxPreference: r.Priority,
+		SrvPriority:  r.Priority,
+		SrvWeight:    r.Weight,
+		SrvPort:      uint16(r.Port),
+		Original:     r,
+	}
+}
+
+func toReq(dc *models.DomainConfig, rc *models.RecordConfig) (*recordEditRequest, error) {
+	req := &recordEditRequest{
+		Type:     rc.Type,
+		Name:     dnsutil.TrimDomainName(rc.NameFQDN, dc.Name),
+		Target:   rc.Target,
+		TTL:      int(rc.TTL),
+		Priority: 0,
+		Port:     int(rc.SrvPort),
+		Weight:   int(rc.SrvWeight),
+	}
+
+	// Linode doesn't use "@", it uses an empty name
+	if req.Name == "@" {
+		req.Name = ""
+	}
+
+	// Linode uses the same property for MX and SRV priority
+	switch rc.Type { // #rtype_variations
+	case "A", "AAAA", "NS", "PTR", "TXT", "SOA", "TLSA", "CAA":
+		// Nothing special.
+	case "MX":
+		req.Priority = int(rc.MxPreference)
+		req.Target = fixTarget(req.Target, dc.Name)
+	case "SRV":
+		req.Priority = int(rc.SrvPriority)
+
+		// From softlayer provider
+		// This is to support SRV, it doesn't work yet for Linode
+		result := srvRegexp.FindStringSubmatch(req.Name)
+
+		if len(result) != 3 {
+			return nil, fmt.Errorf("SRV Record must match format \"_service._protocol\" not %s", req.Name)
+		}
+
+		var serviceName, protocol string = result[1], strings.ToLower(result[2])
+
+		req.Protocol = protocol
+		req.Service = serviceName
+		req.Name = ""
+	case "CNAME":
+		req.Target = fixTarget(req.Target, dc.Name)
+	default:
+		msg := fmt.Sprintf("linode.toReq rtype %v unimplemented", rc.Type)
+		panic(msg)
+		// We panic so that we quickly find any switch statements
+		// that have not been updated for a new RR type.
+	}
+
+	return req, nil
+}
+
+func fixTarget(target, domain string) string {
+	// Linode always wants a fully qualified target name
+	if target[len(target)-1] == '.' {
+		return target[:len(target)-1]
+	} else {
+		return fmt.Sprintf("%s.%s", target, domain)
+	}
+}
+
+func fixTTL(ttl uint32) uint32 {
+	// if the TTL is larger than the largest allowed value, return the largest allowed value
+	if ttl > allowedTTLValues[len(allowedTTLValues)-1] {
+		return allowedTTLValues[len(allowedTTLValues)-1]
+	}
+
+	for _, v := range allowedTTLValues {
+		if v >= ttl {
+			return v
+		}
+	}
+
+	return allowedTTLValues[0]
+}

providers/linode/linodeProvider_test.go

@@ -0,0 +1,23 @@
+package linode
+
+import (
+	"testing"
+)
+
+func TestFixTTL(t *testing.T) {
+	for i, test := range []struct {
+		given, expected uint32
+	}{
+		{299, 300},
+		{300, 300},
+		{301, 3600},
+		{2419202, 2419200},
+		{600, 3600},
+		{3600, 3600},
+	} {
+		found := fixTTL(test.given)
+		if found != test.expected {
+			t.Errorf("Test %d: Expected %d, but was %d", i, test.expected, found)
+		}
+	}
+}