Migrate to new swagger docs generation (#18)

vendor/github.com/swaggo/swag/swagger.go

@@ -0,0 +1,41 @@
+package swag
+
+import (
+	"errors"
+	"sync"
+)
+
+// Name is a unique name be used to register swag instance.
+const Name = "swagger"
+
+var (
+	swaggerMu sync.RWMutex
+	swag      Swagger
+)
+
+// Swagger is a interface to read swagger document.
+type Swagger interface {
+	ReadDoc() string
+}
+
+// Register registers swagger for given name.
+func Register(name string, swagger Swagger) {
+	swaggerMu.Lock()
+	defer swaggerMu.Unlock()
+	if swagger == nil {
+		panic("swagger is nil")
+	}
+
+	if swag != nil {
+		panic("Register called twice for swag: " + name)
+	}
+	swag = swagger
+}
+
+// ReadDoc reads swagger document.
+func ReadDoc() (string, error) {
+	if swag != nil {
+		return swag.ReadDoc(), nil
+	}
+	return "", errors.New("not yet registered swag")
+}