update docgen to embed commit ID in autogenerated doc frontmatter (#1…

…4056)

Signed-off-by: Andrew Mason <andrew@planetscale.com>

go/cmd/internal/docgen/docgen.go

@@ -46,6 +46,7 @@ import (
  "fmt"
  "io/fs"
  "os"
+ "os/exec"
  "path/filepath"
  "strings"
 
@@ -57,6 +58,10 @@ import (
 // written to `dir`. The root command is also renamed to _index.md to remain
 // compatible with the vitessio/website content structure expectations.
 func GenerateMarkdownTree(cmd *cobra.Command, dir string) error {
+ sha, err := getCommitID("HEAD")
+ if err != nil {
+ return fmt.Errorf("failed to get commit id for HEAD: %w", err)
+ }
  switch fi, err := os.Stat(dir); {
  case errors.Is(err, fs.ErrNotExist):
  if err := os.MkdirAll(dir, 0755); err != nil {
@@ -69,7 +74,7 @@ func GenerateMarkdownTree(cmd *cobra.Command, dir string) error {
  }
 
  recursivelyDisableAutoGenTags(cmd)
- if err := doc.GenMarkdownTreeCustom(cmd, dir, frontmatterFilePrepender, linkHandler); err != nil {
+ if err := doc.GenMarkdownTreeCustom(cmd, dir, frontmatterFilePrepender(sha), linkHandler); err != nil {
  return err
  }
 
@@ -91,22 +96,37 @@ func recursivelyDisableAutoGenTags(root *cobra.Command) {
  }
 }
 
+func getCommitID(ref string) (string, error) {
+ gitShow := exec.Command("git", "show", "--pretty=format:%H", "--no-patch", ref)
+ out, err := gitShow.Output()
+ if err != nil {
+ return "", err
+ }
+
+ return string(out), nil
+}
+
 const frontmatter = `---
 title: %s
 series: %s
+commit: %s
 ---
 `
 
-func frontmatterFilePrepender(filename string) string {
- name := filepath.Base(filename)
- base := strings.TrimSuffix(name, filepath.Ext(name))
+func frontmatterFilePrepender(sha string) func(filename string) string {
+ return func(filename string) string {
+ name := filepath.Base(filename)
+ base := strings.TrimSuffix(name, filepath.Ext(name))
 
- root, cmdName, ok := strings.Cut(base, "_")
- if !ok { // no `_`, so not a subcommand
- cmdName = root
- }
+  root, cmdName, ok := strings.Cut(base, "_")
+  if !ok { // no `_`, so not a subcommand
+  cmdName = root
+  }
 
- return fmt.Sprintf(frontmatter, cmdName, root)
+ cmdName = strings.ReplaceAll(cmdName, "_", " ")
+
+ return fmt.Sprintf(frontmatter, cmdName, root, sha)
+ }
 }
 
 func linkHandler(filename string) string {