add footer+gitCommit, sorting for 'appears on'

Signed-off-by: Ahmet Alp Balkan <ahmetb@google.com>

Author: ahmetb

main.go

@@ -10,6 +10,7 @@ import (
 	"io/ioutil"
 	"net/http"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"reflect"
 	"regexp"
@@ -393,6 +394,7 @@ func typeReferences(t *types.Type, c generatorConfig, references map[*types.Type
 	for k := range m {
 		out = append(out, k)
 	}
+	sortTypes(out)
 	return out
 }
 
@@ -401,16 +403,20 @@ func sortedTypes(typs map[string]*types.Type) []*types.Type {
 	for _, t := range typs {
 		out = append(out, t)
 	}
-	sort.Slice(out, func(i, j int) bool {
-		t1, t2 := out[i], out[j]
+	sortTypes(out)
+	return out
+}
+
+func sortTypes(typs []*types.Type) {
+	sort.Slice(typs, func(i, j int) bool {
+		t1, t2 := typs[i], typs[j]
 		if isExportedType(t1) && !isExportedType(t2) {
 			return true
 		} else if !isExportedType(t1) && isExportedType(t2) {
 			return false
 		}
 		return t1.Name.Name < t2.Name.Name
 	})
-	return out
 }
 
 func visibleTypes(in []*types.Type, c generatorConfig) []*types.Type {
@@ -464,6 +470,8 @@ func apiVersionMap(pkgs []*types.Package) (map[string]string, error) {
 func render(w io.Writer, pkgs []*types.Package, config generatorConfig) error {
 	references := findTypeReferences(pkgs)
 
+	gitCommit, _ := exec.Command("git", "rev-parse", "--short", "HEAD").Output()
+
 	apiVersions, err := apiVersionMap(pkgs)
 	if err != nil {
 		return errors.Wrap(err, "failed to infer apiVersions")
@@ -500,7 +508,8 @@ func render(w io.Writer, pkgs []*types.Package, config generatorConfig) error {
 	}
 
 	return errors.Wrap(t.ExecuteTemplate(w, "packages", map[string]interface{}{
-		"packages": pkgs,
-		"config":   config,
+		"packages":  pkgs,
+		"config":    config,
+		"gitCommit": strings.TrimSpace(string(gitCommit)),
 	}), "template execution error")
 }

template/pkg.tpl

@@ -52,4 +52,9 @@ table, td, th {
     <hr/>
 {{ end }}
 
+<p><em>
+    Generated with <code>gen-crd-api-reference-docs</code>
+    {{ with .gitCommit }} on git commit <code>{{ . }}</code>{{end}}.
+</em></p>
+
 {{ end }}