cmd/sgblog-topics/main.go

   1 /*
   2 SGBlog -- Git-backed CGI/UCSPI blogging/phlogging/gemlogging engine
   3 Copyright (C) 2020-2021 Sergey Matveev <stargrave@stargrave.org>
   4
   5 This program is free software: you can redistribute it and/or modify
   6 it under the terms of the GNU Affero General Public License as
   7 published by the Free Software Foundation, version 3 of the License.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU Affero General Public License
  15 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 // Git-backed CGI/UCSPI blogging/phlogging/gemlogging engine
  19 package main
  20
  21 import (
  22         "flag"
  23         "fmt"
  24         "log"
  25         "sort"
  26
  27         "github.com/go-git/go-git/v5"
  28         "github.com/go-git/go-git/v5/plumbing"
  29         "github.com/go-git/go-git/v5/plumbing/object"
  30         "go.stargrave.org/sgblog"
  31 )
  32
  33 func main() {
  34         branch := flag.String("branch", "refs/heads/master", "Blog's branch reference name")
  35         topicsRefName := flag.String("topics-ref", "refs/notes/topics", "Topics reference name")
  36         flag.Usage = func() {
  37                 fmt.Fprintln(flag.CommandLine.Output(), "Show known topics")
  38                 flag.PrintDefaults()
  39         }
  40         flag.Parse()
  41         log.SetFlags(0)
  42
  43         repo, err := git.PlainOpen(".")
  44         if err != nil {
  45                 log.Fatalln(err)
  46         }
  47         head, err := repo.Reference(plumbing.ReferenceName(*branch), false)
  48         if err != nil {
  49                 log.Fatalln(err)
  50         }
  51         headHash := head.Hash()
  52
  53         var topicsRef *plumbing.Reference
  54         var topicsTree *object.Tree
  55         if notes, err := repo.Notes(); err == nil {
  56                 notes.ForEach(func(ref *plumbing.Reference) error {
  57                         if string(ref.Name()) == *topicsRefName {
  58                                 topicsRef = ref
  59                         }
  60                         return nil
  61                 })
  62                 if topicsRef != nil {
  63                         if topicsCommit, err := repo.CommitObject(topicsRef.Hash()); err == nil {
  64                                 topicsTree, _ = topicsCommit.Tree()
  65                         }
  66                 }
  67         }
  68
  69         repoLog, err := repo.Log(&git.LogOptions{From: headHash})
  70         if err != nil {
  71                 log.Fatalln(err)
  72         }
  73         topicsCounter := map[string]int{}
  74         for {
  75                 commit, err := repoLog.Next()
  76                 if err != nil {
  77                         break
  78                 }
  79                 for _, topic := range sgblog.ParseTopics(sgblog.GetNote(repo, topicsTree, commit.Hash)) {
  80                         topicsCounter[topic]++
  81                 }
  82         }
  83         topics := make([]string, 0, len(topicsCounter))
  84         for topic := range topicsCounter {
  85                 topics = append(topics, topic)
  86         }
  87         sort.Strings(topics)
  88         for _, topic := range topics {
  89                 fmt.Printf("%s\t%d\n", topic, topicsCounter[topic])
  90         }
  91 }