Start abstracting away the ACME provider (#830)

* Start abstracting away the ACME provider

* Move ACME to interface with sub-package implementations

* Addressing comments

* Library -> Provider

* Missed a couple of Library -> Provider

* One more Library -> Provider

* remove constants

api/server/acme/acme.go

@@ -0,0 +1,16 @@
+// Package acme abstracts away various ACME libraries
+package acme
+
+import (
+	"errors"
+	"net"
+)
+
+var (
+	ErrProviderNotImplemented = errors.New("Provider not implemented")
+)
+
+// Provider is a ACME provider interface
+type Provider interface {
+	NewListener(...string) (net.Listener, error)
+}

api/server/acme/autocert/autocert.go

@@ -0,0 +1,22 @@
+// Package autocert is the ACME interpreter from golang.org/x/crypto/acme/autocert
+package autocert
+
+import (
+	"net"
+
+	"github.com/micro/go-micro/api/server/acme"
+	"golang.org/x/crypto/acme/autocert"
+)
+
+// autoCertACME is the ACME provider from golang.org/x/crypto/acme/autocert
+type autocertProvider struct{}
+
+// NewListener implements acme.Provider
+func (a *autocertProvider) NewListener(ACMEHosts ...string) (net.Listener, error) {
+	return autocert.NewListener(ACMEHosts...), nil
+}
+
+// New returns an autocert acme.Provider
+func New() acme.Provider {
+	return &autocertProvider{}
+}

api/server/acme/autocert/autocert_test.go

@@ -0,0 +1,15 @@
+package autocert
+
+import (
+	"testing"
+)
+
+func TestAutocert(t *testing.T) {
+	l := New()
+	if _, ok := l.(*autocertProvider); !ok {
+		t.Error("New() didn't return an autocertProvider")
+	}
+	if _, err := l.NewListener(); err != nil {
+		t.Error(err.Error())
+	}
+}

api/server/http/http.go

@@ -11,7 +11,6 @@ import (
 	"github.com/gorilla/handlers"
 	"github.com/micro/go-micro/api/server"
 	"github.com/micro/go-micro/util/log"
-	"golang.org/x/crypto/acme/autocert"
 )
 
 type httpServer struct {
@@ -55,7 +54,7 @@ func (s *httpServer) Start() error {
 
 	if s.opts.EnableACME {
 		// should we check the address to make sure its using :443?
-		l = autocert.NewListener(s.opts.ACMEHosts...)
+		l, err = s.opts.ACMEProvider.NewListener(s.opts.ACMEHosts...)
 	} else if s.opts.EnableTLS && s.opts.TLSConfig != nil {
 		l, err = tls.Listen("tcp", s.address, s.opts.TLSConfig)
 	} else {

api/server/options.go

@@ -2,15 +2,24 @@ package server
 
 import (
 	"crypto/tls"
+
+	"github.com/micro/go-micro/api/server/acme"
 )
 
 type Option func(o *Options)
 
 type Options struct {
-	EnableACME bool
-	EnableTLS  bool
-	ACMEHosts  []string
-	TLSConfig  *tls.Config
+	EnableACME   bool
+	ACMEProvider acme.Provider
+	EnableTLS    bool
+	ACMEHosts    []string
+	TLSConfig    *tls.Config
+}
+
+func EnableACME(b bool) Option {
+	return func(o *Options) {
+		o.EnableACME = b
+	}
 }
 
 func ACMEHosts(hosts ...string) Option {
@@ -19,9 +28,9 @@ func ACMEHosts(hosts ...string) Option {
 	}
 }
 
-func EnableACME(b bool) Option {
+func ACMEProvider(p acme.Provider) Option {
 	return func(o *Options) {
-		o.EnableACME = b
+		o.ACMEProvider = p
 	}
 }