Support multiple templates for graphite serializers (#7136)

internal/config/config.go

@@ -1891,6 +1891,18 @@ func buildSerializer(name string, tbl *ast.Table) (serializers.Serializer, error
 		}
 	}
 
+	if node, ok := tbl.Fields["templates"]; ok {
+		if kv, ok := node.(*ast.KeyValue); ok {
+			if ary, ok := kv.Value.(*ast.Array); ok {
+				for _, elem := range ary.Value {
+					if str, ok := elem.(*ast.String); ok {
+						c.Templates = append(c.Templates, str.Value)
+					}
+				}
+			}
+		}
+	}
+
 	if node, ok := tbl.Fields["influx_max_line_bytes"]; ok {
 		if kv, ok := node.(*ast.KeyValue); ok {
 			if integer, ok := kv.Value.(*ast.Integer); ok {
@@ -2046,6 +2058,7 @@ func buildSerializer(name string, tbl *ast.Table) (serializers.Serializer, error
 	delete(tbl.Fields, "data_format")
 	delete(tbl.Fields, "prefix")
 	delete(tbl.Fields, "template")
+	delete(tbl.Fields, "templates")
 	delete(tbl.Fields, "json_timestamp_units")
 	delete(tbl.Fields, "splunkmetric_hec_routing")
 	delete(tbl.Fields, "splunkmetric_multimetric")