Basic server app with WS connection.

server/internal/services/core/options.go

@@ -0,0 +1,14 @@
+package core
+
+import (
+	"errors"
+)
+
+// ServiceNameOptions is a name for options service which controls options storage.
+const ServiceNameOptions = "core/options"
+
+// ErrOptionsIsInvalid appears when options service implementation is invalid.
+var ErrOptionsIsInvalid = errors.New("options service implementation is invalid")
+
+// Options is an interface for options service.
+type Options interface{}