feat: add Vault

Co-authored-by: Dmitry Fedotov <dmitry@uint32.ru>
Co-committed-by: Dmitry Fedotov <dmitry@uint32.ru>

internal/vault/vault_test.go

@@ -0,0 +1,57 @@
+package vault
+
+import (
+	"bytes"
+	"os"
+	"testing"
+)
+
+func TestVaultStorage(t *testing.T) {
+	token, ok := os.LookupEnv("V_TOKEN")
+	if !ok {
+		t.Skip("no V_TOKEN")
+	}
+
+	addr, ok := os.LookupEnv("V_ADDR")
+	if !ok {
+		t.Skip("no V_ADDR")
+	}
+
+	path, ok := os.LookupEnv("V_PATH")
+	if !ok {
+		t.Skip("no V_PATH")
+	}
+
+	t.Log(addr)
+	t.Log(path)
+
+	st, err := Open(token, path, addr)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	testkey := "testkey"
+	data := []byte("this is a test")
+
+	if err := st.Save(testkey, data); err != nil {
+		t.Error(err)
+	}
+
+	b, err := st.Load(testkey)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !bytes.Equal(data, b) {
+		t.Errorf("values are not equal, want: %s, have: %s", string(data), string(b))
+	}
+
+	if err := st.Delete(testkey); err != nil {
+		t.Error(err)
+	}
+
+	b, err = st.Load(testkey)
+	if err == nil {
+		t.Log("nil error when loading deleted key")
+	}
+}