permissions: introduce utility to convert string map of permissions into AccountPermission

permission/types/util.go

+package types
+
+// ConvertMapStringIntToPermissions converts a map of string-integer pairs and a slice of
+// strings for the roles to an AccountPermissions type.  The integer needs to be greater
+// than zero to set the permission.  For all unmentioned permissions the ZeroBasePermissions
+// is defaulted to.
+// TODO: [ben] re-evaluate the use of int for setting the permission.
+func ConvertPermissionsMapAndRolesToAccountPermissions(permissions map[string]int, roles []string) (*AccountPermissions, error) {
+	var err error
+	accountPermissions := &AccountPermissions{}
+	accountPermissions.Base, err = convertPermissionsMapStringIntToBasePermissions(permissions)
+	if err != nil {
+		return nil, err
+	}
+	accountPermissions.Roles = roles
+	return accountPermissions, nil
+}
+
+// convertPermissionsMapStringIntToBasePermissions converts a map of string-integer pairs to
+// BasePermissions.
+func convertPermissionsMapStringIntToBasePermissions(permissions map[string]int) (BasePermissions, error) {
+	// initialise basePermissions as ZeroBasePermissions
+	basePermissions := ZeroBasePermissions
+
+	for permissionName, value := range permissions {
+		permissionsFlag, err := PermStringToFlag(permissionName)
+		if err != nil {
+			return basePermissions, err
+		}
+		// sets the permissions bitflag and the setbit flag for the permission.
+		basePermissions.Set(permissionsFlag, value > 0)
+	}
+
+	return basePermissions, nil
+}