1 files changed, 114 insertions, 0 deletions
diff --git a/directives_generate.go b/directives_generate.go
new file mode 100644
index 000000000..c6c719fc6
--- /dev/null
+++ b/directives_generate.go
@@ -0,0 +1,114 @@
+//+build ignore
+
+package main
+
+import (
+	"bufio"
+	"go/format"
+	"io/ioutil"
+	"log"
+	"os"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	mi := make(map[string]string, 0)
+	md := make(map[int]string, 0)
+
+	file, err := os.Open(middlewareFile)
+	fatalIfErr(err)
+
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := scanner.Text()
+		if !strings.HasPrefix(line, `//`) && !strings.HasPrefix(line, "#") {
+			items := strings.Split(line, ":")
+			if len(items) == 3 {
+				if priority, err := strconv.Atoi(items[0]); err == nil {
+					md[priority] = items[1]
+				}
+
+				if items[2] != "" {
+					if strings.Contains(items[2], "/") {
+						mi[items[1]] = items[2]
+					} else {
+						mi[items[1]] = middlewarePath + items[2]
+					}
+				}
+
+			}
+		}
+	}
+
+	genImports("core/zmiddleware.go", "core", mi)
+	genDirectives("core/dnsserver/zdirectives.go", "dnsserver", md)
+}
+
+func genImports(file, pack string, mi map[string]string) {
+	outs := header + "package " + pack + "\n\n" + "import ("
+
+	if len(mi) > 0 {
+		outs += "\n"
+	}
+
+	for _, v := range mi {
+		outs += `_ "` + v + `\` + "\n"
+	}
+	outs += ")\n"
+
+	res, err := format.Source([]byte(outs))
+	fatalIfErr(err)
+
+	err = ioutil.WriteFile(file, res, 0644)
+	fatalIfErr(err)
+}
+
+func genDirectives(file, pack string, md map[int]string) {
+
+	outs := header + "package " + pack + "\n\n"
+	outs += `
+// Directives are registered in the order they should be
+// executed.
+//
+// Ordering is VERY important. Every middleware will
+// feel the effects of all other middleware below
+// (after) them during a request, but they must not
+// care what middleware above them are doing.
+
+var directives = []string{
+`
+
+	var orders []int
+	for k := range md {
+		orders = append(orders, k)
+	}
+	sort.Ints(orders)
+
+	for _, k := range orders {
+		outs += `"` + md[k] + `",` + "\n"
+	}
+
+	outs += "}\n"
+
+	res, err := format.Source([]byte(outs))
+	fatalIfErr(err)
+
+	err = ioutil.WriteFile(file, res, 0644)
+	fatalIfErr(err)
+}
+
+func fatalIfErr(err error) {
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+const (
+	middlewarePath = "github.com/miekg/coredns/middleware/"
+	middlewareFile = "middleware.cfg"
+	header         = "// generated by directives_generate.go; DO NOT EDIT\n"
+)