Automatic generation of the doc for the CLI flags and env vars.

internal/gendoc.go

@@ -0,0 +1,83 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"github.com/containous/traefik/pkg/config/env"
+	"github.com/containous/traefik/pkg/config/flag"
+	"github.com/containous/traefik/pkg/config/generator"
+	"github.com/containous/traefik/pkg/config/parser"
+	"github.com/containous/traefik/pkg/config/static"
+	"github.com/containous/traefik/pkg/log"
+)
+
+func main() {
+	genStaticConfDoc("./docs/content/reference/static-configuration/env-ref.md", "", env.Encode)
+	genStaticConfDoc("./docs/content/reference/static-configuration/cli-ref.md", "--", flag.Encode)
+}
+
+func genStaticConfDoc(outputFile string, prefix string, encodeFn func(interface{}) ([]parser.Flat, error)) {
+	logger := log.WithoutContext().WithField("file", outputFile)
+
+	element := &static.Configuration{}
+
+	generator.Generate(element)
+
+	flats, err := encodeFn(element)
+	if err != nil {
+		logger.Fatal(err)
+	}
+
+	err = os.RemoveAll(outputFile)
+	if err != nil {
+		logger.Fatal(err)
+	}
+
+	file, err := os.OpenFile(outputFile, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
+	if err != nil {
+		logger.Fatal(err)
+	}
+
+	defer file.Close()
+
+	w := errWriter{w: file}
+
+	w.writeln(`<!--
+CODE GENERATED AUTOMATICALLY
+THIS FILE MUST NOT BE EDITED BY HAND
+-->
+`)
+
+	for i, flat := range flats {
+		w.writeln("`" + prefix + strings.ReplaceAll(flat.Name, "[0]", "[n]") + "`:  ")
+		if flat.Default == "" {
+			w.writeln(flat.Description)
+		} else {
+			w.writeln(flat.Description + " (Default: ```" + flat.Default + "```)")
+		}
+
+		if i < len(flats)-1 {
+			w.writeln()
+		}
+	}
+
+	if w.err != nil {
+		logger.Fatal(err)
+	}
+}
+
+type errWriter struct {
+	w   io.Writer
+	err error
+}
+
+func (ew *errWriter) writeln(a ...interface{}) {
+	if ew.err != nil {
+		return
+	}
+
+	_, ew.err = fmt.Fprintln(ew.w, a...)
+}