Ensure correct encryption key is provided if using populated data store

kvs/db.go

@@ -15,9 +15,11 @@
 package kvs
 
 import (
+	"fmt"
 	"strings"
 
 	"github.com/abcum/surreal/cnf"
+	"github.com/abcum/surreal/util/keys"
 )
 
 var stores = make(map[string]func(*cnf.Options) (DS, error))
@@ -44,7 +46,29 @@ func New(opts *cnf.Options) (db *DB, err error) {
 		ds, err = stores["pgsql"](opts)
 	}
 
-	return &DB{ds: ds}, err
+	db = &DB{ds: ds}
+
+	err = db.enc(opts)
+
+	return
+
+}
+
+func (db *DB) enc(opts *cnf.Options) (err error) {
+
+	ck := &keys.CK{KV: opts.DB.Base}
+
+	kv, _ := db.Get(ck.Encode())
+
+	if kv.Exists() == false {
+		err = db.Put(ck.Encode(), []byte("±"))
+	}
+
+	if kv.Exists() == true && kv.Str() != "±" {
+		err = fmt.Errorf("Please provide a valid encryption key for the stored data.")
+	}
+
+	return
 
 }
 

util/keys/ck.go

@@ -0,0 +1,51 @@
+// Copyright © 2016 Abcum Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package keys
+
+import (
+	"fmt"
+)
+
+// CK ...
+type CK struct {
+	KV interface{}
+	CF interface{}
+	CK interface{}
+}
+
+// init initialises the key
+func (k *CK) init() *CK {
+	k.CF = "!"
+	k.CK = "¥"
+	return k
+}
+
+// Encode encodes the key into binary
+func (k *CK) Encode() []byte {
+	k.init()
+	return encode(k.KV, k.CF, k.CK)
+}
+
+// Decode decodes the key from binary
+func (k *CK) Decode(data []byte) {
+	k.init()
+	decode(data, &k.KV, &k.CF, &k.CK)
+}
+
+// String returns a string representation of the key
+func (k *CK) String() string {
+	k.init()
+	return fmt.Sprintf("/%s/%s/%s", k.KV, k.CF, k.CK)
+}