Add Linode support

README.md

@@ -24,6 +24,7 @@ A [Rancher](http://rancher.com/rancher/) service that obtains free SSL/TLS certi
   * `DNSimple`
   * `Dyn`
   * `Gandi`
+  * `Linode`
   * `NS1`
   * `Ovh`
   * `Vultr`
@@ -110,6 +111,8 @@ Then make sure that HTTP requests to `domain.com/.well-known/acme-challenge` are
 
 `make build && make image`
 
+This project uses [trash](https://github.com/rancher/trash) to manage dependencies.
+
 ### Contributions
 
 PR's welcome!

context.go

@@ -126,6 +126,7 @@ func (c *Context) InitContext() {
 		OvhConsumerKey:       getEnvOption("OVH_CONSUMER_KEY", false),
 		GandiApiKey:          getEnvOption("GANDI_API_KEY", false),
 		NS1ApiKey:            getEnvOption("NS1_API_KEY", false),
+		LinodeApiKey:         getEnvOption("LINODE_API_KEY", false),
 	}
 
 	c.Acme, err = letsencrypt.NewClient(emailParam, keyType, apiVersion, dnsResolvers, providerOpts)

letsencrypt/providers.go

@@ -12,6 +12,7 @@ import (
 	"github.com/xenolf/lego/providers/dns/dnsimple"
 	"github.com/xenolf/lego/providers/dns/dyn"
 	"github.com/xenolf/lego/providers/dns/gandi"
+	"github.com/xenolf/lego/providers/dns/linode"
 	"github.com/xenolf/lego/providers/dns/ns1"
 	"github.com/xenolf/lego/providers/dns/ovh"
 	"github.com/xenolf/lego/providers/dns/route53"
@@ -58,6 +59,9 @@ type ProviderOpts struct {
 	// Gandi credentials
 	GandiApiKey string
 
+	// Linode credentials
+	LinodeApiKey string
+
 	// NS1 credentials
 	NS1ApiKey string
 
@@ -80,6 +84,7 @@ const (
 	DNSIMPLE     = Provider("DNSimple")
 	DYN          = Provider("Dyn")
 	GANDI        = Provider("Gandi")
+	LINODE       = Provider("Linode")
 	NS1          = Provider("NS1")
 	OVH          = Provider("Ovh")
 	ROUTE53      = Provider("Route53")
@@ -100,6 +105,7 @@ var providerFactory = map[Provider]ProviderFactory{
 	DNSIMPLE:     ProviderFactory{makeDNSimpleProvider, lego.DNS01},
 	DYN:          ProviderFactory{makeDynProvider, lego.DNS01},
 	GANDI:        ProviderFactory{makeGandiProvider, lego.DNS01},
+	LINODE:       ProviderFactory{makeLinodeProvider, lego.DNS01},
 	NS1:          ProviderFactory{makeNS1Provider, lego.DNS01},
 	OVH:          ProviderFactory{makeOvhProvider, lego.DNS01},
 	ROUTE53:      ProviderFactory{makeRoute53Provider, lego.DNS01},
@@ -275,6 +281,19 @@ func makeGandiProvider(opts ProviderOpts) (lego.ChallengeProvider, error) {
 	return provider, nil
 }
 
+// returns a preconfigured Linode lego.ChallengeProvider
+func makeLinodeProvider(opts ProviderOpts) (lego.ChallengeProvider, error) {
+	if len(opts.LinodeApiKey) == 0 {
+		return nil, fmt.Errorf("Linode API key is not set")
+	}
+
+	provider, err := linode.NewDNSProviderCredentials(opts.LinodeApiKey)
+	if err != nil {
+		return nil, err
+	}
+	return provider, nil
+}
+
 // returns a preconfigured HTTP lego.ChallengeProvider
 func makeHTTPProvider(opts ProviderOpts) (lego.ChallengeProvider, error) {
 	provider := lego.NewHTTPProviderServer("", "")

vendor.conf

@@ -18,6 +18,7 @@ github.com/ovh/go-ovh								d220717
 github.com/pkg/errors								c605e28
 github.com/rancher/go-rancher/v2					939fd85
 github.com/Sirupsen/logrus							v0.11.5
+github.com/timewasted/linode/dns                    37e8452
 github.com/xenolf/lego								aaa8e70
 golang.org/x/crypto									ab89591
 golang.org/x/net									84f0e6f