cmd/sgblog/gopher.go

   1 /*
   2 SGBlog -- Git-backed CGI/inetd blogging/phlogging 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 package main
  19
  20 import (
  21         "bufio"
  22         "encoding/json"
  23         "errors"
  24         "fmt"
  25         "io"
  26         "io/ioutil"
  27         "log"
  28         "os"
  29         "strconv"
  30         "strings"
  31         "text/template"
  32
  33         "github.com/go-git/go-git/v5"
  34         "github.com/go-git/go-git/v5/plumbing"
  35         "github.com/go-git/go-git/v5/plumbing/object"
  36         "github.com/hjson/hjson-go"
  37         "go.stargrave.org/sgblog"
  38 )
  39
  40 const (
  41         TmplGopherMenu = `{{$CR := printf "\r"}}{{$CRLF := printf "\r\n" -}}
  42 {{- define "domainPort" }}      {{.GopherDomain}}       70{{end}}{{$Cfg := .Cfg -}}
  43 i{{.Cfg.Title}} {{if .Topic}}(topic: {{.Topic}}) {{end}}({{.Offset}}-{{.OffsetNext}})   err{{template "domainPort" .Cfg}}{{$CRLF -}}
  44 {{- if .Cfg.AboutURL}}hAbout    URL:{{.Cfg.AboutURL}}{{template "domainPort" .Cfg}}{{$CRLF}}{{end -}}
  45 {{- if .Offset}}1Prev   {{if .Topic}}{{.Topic}}/{{end}}offset/{{.OffsetPrev}}{{template "domainPort" .Cfg}}{{$CRLF}}{{end -}}
  46 {{- if not .LogEnded}}1Next     {{if .Topic}}{{.Topic}}/{{end}}offset/{{.OffsetNext}}{{template "domainPort" .Cfg}}{{$CRLF}}{{end -}}
  47 {{- $datePrev := "0001-01-01" -}}
  48 {{- range .Entries -}}
  49 {{- $dateCur := .Commit.Author.When.Format "2006-01-02" -}}
  50 {{- if ne $dateCur $datePrev}}{{$datePrev = $dateCur}}
  51 i{{$dateCur}}   err{{template "domainPort" $Cfg}}{{$CR}}{{end}}
  52 0[{{.Commit.Author.When.Format "15:04"}}] {{.Title}} ({{.LinesNum}}L){{with .CommentsNum}} ({{.}}C){{end}}{{if .Topics}}{{range .Topics}} {{.}}{{end}}{{end}}   /{{.Commit.Hash.String}}{{template "domainPort" $Cfg}}{{$CR}}{{end}}
  53 {{range .Topics}}
  54 1Topic: {{.}}   {{.}}/offset/0{{template "domainPort" $Cfg}}{{$CR}}{{end}}
  55 iGenerated by: SGBlog {{.Version}}      err{{template "domainPort" .Cfg}}{{$CR}}
  56 .{{$CRLF}}`
  57         TmplGopherEntry = `What: {{.Commit.Hash.String}}
  58 When: {{.When}}
  59 ------------------------------------------------------------------------
  60 {{if .Topics}}Topics:{{range .Topics}} {{.}}{{end}}{{end}}
  61 ------------------------------------------------------------------------
  62 {{.Commit.Message -}}
  63 {{- if .Note}}
  64 ------------------------------------------------------------------------
  65 Note:
  66 {{.Note}}{{end -}}
  67 {{- if .Cfg.CommentsEmail}}
  68 ------------------------------------------------------------------------
  69 leave comment: mailto:{{.Cfg.CommentsEmail}}?subject={{.Commit.Hash.String}}
  70 {{end}}{{range $idx, $comment := .Comments}}
  71 ------------------------------------------------------------------------
  72 comment {{$idx}}:
  73 {{$comment}}
  74 {{end}}
  75 ------------------------------------------------------------------------
  76 Generated by: SGBlog {{.Version}}
  77 `
  78 )
  79
  80 type TableMenuEntry struct {
  81         Commit      *object.Commit
  82         Title       string
  83         LinesNum    int
  84         CommentsNum int
  85         Topics      []string
  86 }
  87
  88 func serveGopher() {
  89         cfgPath := os.Args[2]
  90         cfgRaw, err := ioutil.ReadFile(cfgPath)
  91         if err != nil {
  92                 log.Fatalln(err)
  93         }
  94         var cfgGeneral map[string]interface{}
  95         if err = hjson.Unmarshal(cfgRaw, &cfgGeneral); err != nil {
  96                 log.Fatalln(err)
  97         }
  98         cfgRaw, err = json.Marshal(cfgGeneral)
  99         if err != nil {
 100                 log.Fatalln(err)
 101         }
 102         var cfg *Cfg
 103         if err = json.Unmarshal(cfgRaw, &cfg); err != nil {
 104                 log.Fatalln(err)
 105         }
 106         if cfg.GopherDomain == "" {
 107                 log.Fatalln("GopherDomain is not configured")
 108         }
 109
 110         headHash, err := initRepo(cfg)
 111         if err != nil {
 112                 log.Fatalln(err)
 113         }
 114
 115         scanner := bufio.NewScanner(io.LimitReader(os.Stdin, 1<<8))
 116         if !scanner.Scan() {
 117                 log.Fatalln(errors.New("no CRLF found"))
 118         }
 119         selector := scanner.Text()
 120         if selector == "" {
 121                 selector = "offset/0"
 122         }
 123         selectorParts := strings.Split(selector, "/")
 124         if strings.HasPrefix(selector, "URL:") {
 125                 selector = selector[len("URL:"):]
 126                 fmt.Printf(`<html>
 127 <head>
 128         <meta http-equiv="Refresh" content="1; url=%s" />
 129         <title>Redirect to non-gopher URL</title>
 130 </head>
 131 <body>
 132 Redirecting to <a href="%s">%s</a>...
 133 </body>
 134 </html>
 135 `, selector, selector, selector)
 136         } else if sha1DigestRe.MatchString(selector) {
 137                 commit, err := repo.CommitObject(plumbing.NewHash(selector[1:]))
 138                 if err != nil {
 139                         log.Fatalln(err)
 140                 }
 141                 tmpl := template.Must(template.New("entry").Parse(TmplGopherEntry))
 142                 err = tmpl.Execute(os.Stdout, struct {
 143                         Commit   *object.Commit
 144                         When     string
 145                         Cfg      *Cfg
 146                         Note     string
 147                         Comments []string
 148                         Topics   []string
 149                         Version  string
 150                 }{
 151                         Commit:   commit,
 152                         When:     commit.Author.When.Format(sgblog.WhenFmt),
 153                         Cfg:      cfg,
 154                         Note:     string(getNote(notesTree, commit.Hash)),
 155                         Comments: parseComments(getNote(commentsTree, commit.Hash)),
 156                         Topics:   parseTopics(getNote(topicsTree, commit.Hash)),
 157                         Version:  sgblog.Version,
 158                 })
 159                 if err != nil {
 160                         log.Fatalln(err)
 161                 }
 162         } else if selectorParts[len(selectorParts)-2] == "offset" {
 163                 offset, err := strconv.Atoi(selectorParts[len(selectorParts)-1])
 164                 if err != nil {
 165                         log.Fatalln(err)
 166                 }
 167                 repoLog, err := repo.Log(&git.LogOptions{From: *headHash})
 168                 if err != nil {
 169                         log.Fatalln(err)
 170                 }
 171                 topicsCache, err := getTopicsCache(cfg, repoLog)
 172                 if err != nil {
 173                         log.Fatalln(err)
 174                 }
 175                 repoLog, err = repo.Log(&git.LogOptions{From: *headHash})
 176                 if err != nil {
 177                         log.Fatalln(err)
 178                 }
 179
 180                 var topic string
 181                 if len(selectorParts) == 3 {
 182                         topic = selectorParts[0]
 183                 }
 184                 var commits CommitIterNext
 185                 if topic == "" {
 186                         for i := 0; i < offset; i++ {
 187                                 if _, err = repoLog.Next(); err != nil {
 188                                         break
 189                                 }
 190                         }
 191                         commits = repoLog
 192                 } else {
 193                         hashes := topicsCache[topic]
 194                         if hashes == nil {
 195                                 log.Fatalln(errors.New("no posts with that topic"))
 196                         }
 197                         if len(hashes) > offset {
 198                                 hashes = hashes[offset:]
 199                         }
 200                         commits = &HashesIter{hashes}
 201                 }
 202
 203                 logEnded := false
 204                 entries := make([]TableMenuEntry, 0, PageEntries)
 205                 for i := 0; i < PageEntries; i++ {
 206                         commit, err := commits.Next()
 207                         if err != nil {
 208                                 logEnded = true
 209                                 break
 210                         }
 211                         lines := msgSplit(commit.Message)
 212                         entries = append(entries, TableMenuEntry{
 213                                 Commit:      commit,
 214                                 Title:       lines[0],
 215                                 LinesNum:    len(lines) - 2,
 216                                 CommentsNum: len(parseComments(getNote(commentsTree, commit.Hash))),
 217                                 Topics:      parseTopics(getNote(topicsTree, commit.Hash)),
 218                         })
 219                 }
 220                 tmpl := template.Must(template.New("menu").Parse(TmplGopherMenu))
 221                 offsetPrev := offset - PageEntries
 222                 if offsetPrev < 0 {
 223                         offsetPrev = 0
 224                 }
 225                 err = tmpl.Execute(os.Stdout, struct {
 226                         Cfg        *Cfg
 227                         Topic      string
 228                         Offset     int
 229                         OffsetPrev int
 230                         OffsetNext int
 231                         LogEnded   bool
 232                         Entries    []TableMenuEntry
 233                         Topics     []string
 234                         Version    string
 235                 }{
 236                         Cfg:        cfg,
 237                         Topic:      topic,
 238                         Offset:     offset,
 239                         OffsetPrev: offsetPrev,
 240                         OffsetNext: offset + PageEntries,
 241                         LogEnded:   logEnded,
 242                         Entries:    entries,
 243                         Topics:     topicsCache.Topics(),
 244                         Version:    sgblog.Version,
 245                 })
 246                 if err != nil {
 247                         log.Fatalln(err)
 248                 }
 249         } else {
 250                 log.Fatalln(errors.New("unknown selector"))
 251         }
 252 }