Use db client factory in seeder.

cmd/mtseeder/baselevel.go

@@ -56,7 +56,7 @@ func createTiles(
 }
 
 func createBaseLevel(
-	dbcc dbClientCreator,
+	dbcc common.DBClientCreator,
 	xMin, yMin, zMin, xMax, yMax, zMax int,
 	transparent bool, transparentDim float32,
 	colorsFile string, bg color.RGBA, outDir string,

cmd/mtseeder/main.go

@@ -68,7 +68,7 @@ func main() {
 
 	bg := common.ParseColorDefault(bgColor, common.BackgroundColor)
 
-	dbcc := createDBClientCreator(host, port)
+	dbcc := common.CreateDBClientCreator(host, port)
 
 	if !skipBaseLevel {
 		td := common.Clamp32f(float32(transparentDim/100.0), 0.0, 1.0)

common/clientfactory.go

@@ -0,0 +1,33 @@
+// Copyright 2022 by Sascha L. Teichmann
+// Use of this source code is governed by the MIT license
+// that can be found in the LICENSE file.
+
+package common
+
+import (
+	"fmt"
+	"strings"
+)
+
+type DBClientCreator func() (DBClient, error)
+
+func CreateDBClientCreator(host string, port int) DBClientCreator {
+
+	var address string
+	if strings.ContainsRune(host, '/') {
+		address = host
+	} else {
+		address = fmt.Sprintf("%s:%d", host, port)
+	}
+
+	var proto string
+	if strings.ContainsRune(address, '/') {
+		proto = "unix"
+	} else {
+		proto = "tcp"
+	}
+
+	return func() (DBClient, error) {
+		return NewRedisClient(proto, address)
+	}
+}