Start working on a etcd backend

middleware/etcd/etcd.go

@@ -0,0 +1,34 @@
+// Package etcd provides the etcd backend.
+package etcd
+
+import (
+	"github.com/skynetservices/skydns/singleflight"
+
+	etcd "github.com/coreos/etcd/client"
+	"golang.org/x/net/context"
+)
+
+type (
+	Etcd struct {
+		Ttl      uint32
+		Priority uint16
+		Backend  *Backend
+	}
+)
+
+type Backend struct {
+	client   etcd.KeysAPI
+	ctx      context.Context
+	config   *Config
+	inflight *singleflight.Group
+}
+
+// NewBackend returns a new Backend.
+func NewBackend(client etcd.KeysAPI, ctx context.Context, config *Config) *Backend {
+	return &Backend{
+		client:   client,
+		ctx:      ctx,
+		config:   config,
+		inflight: &singleflight.Group{},
+	}
+}