start implementing db interface

internal/db/const.go

@@ -0,0 +1,36 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package db
+
+import "regexp"
+
+const (
+	// general db defaults
+
+	// default database to use in whatever db implementation we have
+	defaultDatabase string = "gotosocial"
+
+	// implementation-specific defaults
+
+	// widely-recognised default postgres port
+	postgresDefaultPort int = 5432
+)
+
+var ipv4Regex = regexp.MustCompile(`^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$`)
+var hostnameRegex = regexp.MustCompile(`^(?:[a-z0-9]+(?:-[a-z0-9]+)*\.)+[a-z]{2,}$`)