cmd/sgblog/http.go

   1 /*
   2 SGBlog -- Git-backed CGI/UCSPI blogging/phlogging/gemlogging engine
   3 Copyright (C) 2020-2023 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         "bytes"
  22         "compress/gzip"
  23         "crypto/sha1"
  24         _ "embed"
  25         "encoding/hex"
  26         "encoding/xml"
  27         "errors"
  28         "fmt"
  29         "hash"
  30         "html"
  31         "io"
  32         "log"
  33         "net/http"
  34         "net/url"
  35         "os"
  36         "strconv"
  37         "strings"
  38         "text/template"
  39         "time"
  40
  41         "github.com/go-git/go-git/v5"
  42         "github.com/go-git/go-git/v5/plumbing"
  43         "github.com/go-git/go-git/v5/plumbing/object"
  44         "github.com/vorlif/spreak"
  45         "go.stargrave.org/sgblog"
  46         "go.stargrave.org/sgblog/cmd/sgblog/atom"
  47         "golang.org/x/crypto/blake2b"
  48 )
  49
  50 const (
  51         AtomPostsFeed    = "feed.atom"
  52         AtomCommentsFeed = "comments.atom"
  53 )
  54
  55 var (
  56         renderableSchemes = map[string]struct{}{
  57                 "finger": {},
  58                 "ftp":    {},
  59                 "gemini": {},
  60                 "gopher": {},
  61                 "http":   {},
  62                 "https":  {},
  63                 "irc":    {},
  64                 "ircs":   {},
  65                 "news":   {},
  66                 "telnet": {},
  67         }
  68
  69         //go:embed http-index.tmpl
  70         TmplHTMLIndexRaw string
  71         TmplHTMLIndex    = template.Must(template.New("http-index").Parse(TmplHTMLIndexRaw))
  72
  73         //go:embed http-entry.tmpl
  74         TmplHTMLEntryRaw string
  75         TmplHTMLEntry    = template.Must(template.New("http-entry").Funcs(
  76                 template.FuncMap{"lineURLize": lineURLizeInTemplate},
  77         ).Parse(TmplHTMLEntryRaw))
  78 )
  79
  80 type TableEntry struct {
  81         Commit      *object.Commit
  82         CommentsRaw []byte
  83         TopicsRaw   []byte
  84         Num         int
  85         Title       string
  86         LinesNum    int
  87         CommentsNum int
  88         DomainURLs  []string
  89         Topics      []string
  90 }
  91
  92 type CommentEntry struct {
  93         HeaderLines []string
  94         BodyLines   []string
  95 }
  96
  97 func makeA(href, text string) string {
  98         return `<a href="` + href + `">` + text + `</a>`
  99 }
 100
 101 func etagString(etag hash.Hash) string {
 102         return `"` + hex.EncodeToString(etag.Sum(nil)) + `"`
 103 }
 104
 105 func urlParse(what string) *url.URL {
 106         if u, err := url.ParseRequestURI(what); err == nil {
 107                 if _, exists := renderableSchemes[u.Scheme]; exists {
 108                         return u
 109                 }
 110         }
 111         return nil
 112 }
 113
 114 func lineURLize(urlPrefix, line string) string {
 115         cols := strings.Split(html.EscapeString(line), " ")
 116         for i, col := range cols {
 117                 if u := urlParse(col); u != nil {
 118                         cols[i] = makeA(col, col)
 119                         continue
 120                 }
 121                 cols[i] = sha1DigestRe.ReplaceAllString(col, makeA(urlPrefix+"/$1", "$1"))
 122         }
 123         return strings.Join(cols, " ")
 124 }
 125
 126 func lineURLizeInTemplate(urlPrefix, line interface{}) string {
 127         return lineURLize(urlPrefix.(string), line.(string))
 128 }
 129
 130 func startHeader(etag hash.Hash, gziped bool) string {
 131         lines := []string{
 132                 "Content-Type: text/html; charset=utf-8",
 133                 "ETag: " + etagString(etag),
 134         }
 135         if gziped {
 136                 lines = append(lines, "Content-Encoding: gzip")
 137         }
 138         lines = append(lines, "")
 139         lines = append(lines, "")
 140         return strings.Join(lines, "\n")
 141 }
 142
 143 func makeErr(err error, status int) {
 144         fmt.Println("Status:", status)
 145         fmt.Print("Content-Type: text/plain; charset=utf-8\n\n")
 146         fmt.Println(err)
 147         log.Fatalln(err)
 148 }
 149
 150 func checkETag(etag hash.Hash) {
 151         ifNoneMatch := os.Getenv("HTTP_IF_NONE_MATCH")
 152         if ifNoneMatch != "" && ifNoneMatch == etagString(etag) {
 153                 fmt.Printf("Status: 304\nETag: %s\n\n", ifNoneMatch)
 154                 os.Exit(0)
 155         }
 156 }
 157
 158 func bytes2uuid(b []byte) string {
 159         raw := new([16]byte)
 160         copy(raw[:], b)
 161         raw[6] = (raw[6] & 0x0F) | uint8(4<<4) // version 4
 162         return fmt.Sprintf("%x-%x-%x-%x-%x", raw[0:4], raw[4:6], raw[6:8], raw[8:10], raw[10:])
 163 }
 164
 165 type CommitIterNext interface {
 166         Next() (*object.Commit, error)
 167 }
 168
 169 func serveHTTP() {
 170         cfgPath := os.Getenv("SGBLOG_CFG")
 171         if cfgPath == "" {
 172                 log.Fatalln("SGBLOG_CFG is not set")
 173         }
 174         cfg, err := readCfg(cfgPath)
 175         if err != nil {
 176                 log.Fatalln(err)
 177         }
 178         initLocalizer(cfg.Lang)
 179
 180         pathInfo := os.Getenv("PATH_INFO")
 181         if len(pathInfo) == 0 {
 182                 pathInfo = "/"
 183         }
 184         queryValues, err := url.ParseQuery(os.Getenv("QUERY_STRING"))
 185         if err != nil {
 186                 makeErr(err, http.StatusBadRequest)
 187         }
 188
 189         etagHash, err := blake2b.New256(nil)
 190         if err != nil {
 191                 panic(err)
 192         }
 193         for _, s := range []string{
 194                 "SGBLOG",
 195                 sgblog.Version,
 196                 cfg.GitPath,
 197                 cfg.Branch,
 198                 cfg.Title,
 199                 cfg.URLPrefix,
 200                 cfg.AtomBaseURL,
 201                 cfg.AtomId,
 202                 cfg.AtomAuthor,
 203         } {
 204                 if _, err = etagHash.Write([]byte(s)); err != nil {
 205                         panic(err)
 206                 }
 207         }
 208         etagHashForWeb := []string{
 209                 cfg.CSS,
 210                 cfg.Webmaster,
 211                 cfg.AboutURL,
 212                 cfg.CommentsNotesRef,
 213                 cfg.CommentsEmail,
 214         }
 215         etagHashForWeb = append(etagHashForWeb, cfg.GitURLs...)
 216
 217         headHash, err := initRepo(cfg)
 218         if err != nil {
 219                 makeErr(err, http.StatusInternalServerError)
 220         }
 221
 222         if notes, err := repo.Notes(); err == nil {
 223                 var notesRef *plumbing.Reference
 224                 var commentsRef *plumbing.Reference
 225                 notes.ForEach(func(ref *plumbing.Reference) error {
 226                         switch string(ref.Name()) {
 227                         case "refs/notes/commits":
 228                                 notesRef = ref
 229                         case cfg.CommentsNotesRef:
 230                                 commentsRef = ref
 231                         }
 232                         return nil
 233                 })
 234                 if notesRef != nil {
 235                         if commentsCommit, err := repo.CommitObject(notesRef.Hash()); err == nil {
 236                                 notesTree, _ = commentsCommit.Tree()
 237                         }
 238                 }
 239                 if commentsRef != nil {
 240                         if commentsCommit, err := repo.CommitObject(commentsRef.Hash()); err == nil {
 241                                 commentsTree, _ = commentsCommit.Tree()
 242                         }
 243                 }
 244         }
 245
 246         var outBuf bytes.Buffer
 247         var out io.Writer
 248         out = &outBuf
 249         var gzipWriter *gzip.Writer
 250         acceptEncoding := os.Getenv("HTTP_ACCEPT_ENCODING")
 251         for _, encoding := range strings.Split(acceptEncoding, ", ") {
 252                 if encoding == "gzip" {
 253                         gzipWriter = gzip.NewWriter(&outBuf)
 254                         out = gzipWriter
 255                 }
 256         }
 257
 258         if pathInfo == "/" {
 259                 offset := 0
 260                 if offsetRaw, exists := queryValues["offset"]; exists {
 261                         offset, err = strconv.Atoi(offsetRaw[0])
 262                         if err != nil {
 263                                 makeErr(err, http.StatusBadRequest)
 264                         }
 265                 }
 266                 repoLog, err := repo.Log(&git.LogOptions{From: *headHash})
 267                 if err != nil {
 268                         makeErr(err, http.StatusInternalServerError)
 269                 }
 270                 topicsCache, err := getTopicsCache(cfg, repoLog)
 271                 if err != nil {
 272                         makeErr(err, http.StatusInternalServerError)
 273                 }
 274                 repoLog, err = repo.Log(&git.LogOptions{From: *headHash})
 275                 if err != nil {
 276                         makeErr(err, http.StatusInternalServerError)
 277                 }
 278
 279                 commitN := 0
 280                 var commits CommitIterNext
 281                 var topic string
 282                 if t, exists := queryValues["topic"]; exists {
 283                         topic = t[0]
 284                         hashes := topicsCache[topic]
 285                         if hashes == nil {
 286                                 makeErr(errors.New("no posts with that topic"), http.StatusBadRequest)
 287                         }
 288                         if len(hashes) > offset {
 289                                 hashes = hashes[offset:]
 290                                 commitN += offset
 291                         }
 292                         commits = &HashesIter{hashes}
 293                 } else {
 294                         for i := 0; i < offset; i++ {
 295                                 if _, err = repoLog.Next(); err != nil {
 296                                         break
 297                                 }
 298                                 commitN++
 299                         }
 300                         commits = repoLog
 301                 }
 302
 303                 entries := make([]TableEntry, 0, PageEntries)
 304                 logEnded := false
 305                 for _, data := range etagHashForWeb {
 306                         etagHash.Write([]byte(data))
 307                 }
 308                 etagHash.Write([]byte("INDEX"))
 309                 etagHash.Write([]byte(topic))
 310                 for i := 0; i < PageEntries; i++ {
 311                         commit, err := commits.Next()
 312                         if err != nil {
 313                                 logEnded = true
 314                                 break
 315                         }
 316                         etagHash.Write(commit.Hash[:])
 317                         commentsRaw := sgblog.GetNote(repo, commentsTree, commit.Hash)
 318                         etagHash.Write(commentsRaw)
 319                         topicsRaw := sgblog.GetNote(repo, topicsTree, commit.Hash)
 320                         etagHash.Write(topicsRaw)
 321                         entries = append(entries, TableEntry{
 322                                 Commit:      commit,
 323                                 CommentsRaw: commentsRaw,
 324                                 TopicsRaw:   topicsRaw,
 325                         })
 326                 }
 327                 checkETag(etagHash)
 328
 329                 for i, entry := range entries {
 330                         commitN++
 331                         entry.Num = commitN
 332                         lines := msgSplit(entry.Commit.Message)
 333                         entry.Title = lines[0]
 334                         entry.LinesNum = len(lines) - 2
 335                         for _, line := range lines[2:] {
 336                                 u := urlParse(line)
 337                                 if u == nil {
 338                                         break
 339                                 }
 340                                 entry.DomainURLs = append(entry.DomainURLs, makeA(line, u.Host))
 341                         }
 342                         entry.CommentsNum = len(sgblog.ParseComments(entry.CommentsRaw))
 343                         entry.Topics = sgblog.ParseTopics(entry.TopicsRaw)
 344                         entries[i] = entry
 345                 }
 346                 offsetPrev := offset - PageEntries
 347                 if offsetPrev < 0 {
 348                         offsetPrev = 0
 349                 }
 350                 os.Stdout.Write([]byte(startHeader(etagHash, gzipWriter != nil)))
 351                 err = TmplHTMLIndex.Execute(out, struct {
 352                         T                *spreak.Localizer
 353                         Version          string
 354                         Cfg              *Cfg
 355                         Topic            string
 356                         TopicsEnabled    bool
 357                         Topics           []string
 358                         CommentsEnabled  bool
 359                         AtomPostsFeed    string
 360                         AtomCommentsFeed string
 361                         Offset           int
 362                         OffsetPrev       int
 363                         OffsetNext       int
 364                         LogEnded         bool
 365                         Entries          []TableEntry
 366                 }{
 367                         T:                localizer,
 368                         Version:          sgblog.Version,
 369                         Cfg:              cfg,
 370                         Topic:            topic,
 371                         TopicsEnabled:    topicsTree != nil,
 372                         Topics:           topicsCache.Topics(),
 373                         CommentsEnabled:  commentsTree != nil,
 374                         AtomPostsFeed:    AtomPostsFeed,
 375                         AtomCommentsFeed: AtomCommentsFeed,
 376                         Offset:           offset,
 377                         OffsetPrev:       offsetPrev,
 378                         OffsetNext:       offset + PageEntries,
 379                         LogEnded:         logEnded,
 380                         Entries:          entries,
 381                 })
 382                 if err != nil {
 383                         makeErr(err, http.StatusInternalServerError)
 384                 }
 385         } else if pathInfo == "/twtxt.txt" {
 386                 commit, err := repo.CommitObject(*headHash)
 387                 if err != nil {
 388                         makeErr(err, http.StatusInternalServerError)
 389                 }
 390                 etagHash.Write([]byte("TWTXT POSTS"))
 391                 etagHash.Write(commit.Hash[:])
 392                 checkETag(etagHash)
 393                 repoLog, err := repo.Log(&git.LogOptions{From: *headHash})
 394                 if err != nil {
 395                         makeErr(err, http.StatusInternalServerError)
 396                 }
 397                 for i := 0; i < PageEntries; i++ {
 398                         commit, err = repoLog.Next()
 399                         if err != nil {
 400                                 break
 401                         }
 402                         fmt.Fprintf(
 403                                 out, "%s\t%s\n",
 404                                 commit.Author.When.Format(time.RFC3339),
 405                                 msgSplit(commit.Message)[0],
 406                         )
 407                 }
 408                 os.Stdout.WriteString("Content-Type: text/plain; charset=utf-8\n")
 409                 os.Stdout.WriteString("ETag: " + etagString(etagHash) + "\n")
 410                 if gzipWriter != nil {
 411                         os.Stdout.WriteString("Content-Encoding: gzip\n")
 412                         gzipWriter.Close()
 413                 }
 414                 os.Stdout.WriteString("\n")
 415                 os.Stdout.Write(outBuf.Bytes())
 416                 return
 417         } else if pathInfo == "/"+AtomPostsFeed {
 418                 commit, err := repo.CommitObject(*headHash)
 419                 if err != nil {
 420                         makeErr(err, http.StatusInternalServerError)
 421                 }
 422
 423                 var topic string
 424                 if t, exists := queryValues["topic"]; exists {
 425                         topic = t[0]
 426                 }
 427
 428                 etagHash.Write([]byte("ATOM POSTS"))
 429                 etagHash.Write([]byte(topic))
 430                 etagHash.Write(commit.Hash[:])
 431                 checkETag(etagHash)
 432                 var title string
 433                 if topic == "" {
 434                         title = cfg.Title
 435                 } else {
 436                         title = fmt.Sprintf("%s (topic: %s)", cfg.Title, topic)
 437                 }
 438                 idHasher, err := blake2b.New256(nil)
 439                 if err != nil {
 440                         panic(err)
 441                 }
 442                 idHasher.Write([]byte("ATOM POSTS"))
 443                 idHasher.Write([]byte(cfg.AtomId))
 444                 idHasher.Write([]byte(topic))
 445                 feed := atom.Feed{
 446                         Title:   title,
 447                         ID:      "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 448                         Updated: atom.Time(commit.Author.When),
 449                         Link: []atom.Link{{
 450                                 Rel:  "self",
 451                                 Href: cfg.AtomBaseURL + cfg.URLPrefix + "/" + AtomPostsFeed,
 452                         }},
 453                         Author: &atom.Person{Name: cfg.AtomAuthor},
 454                 }
 455
 456                 repoLog, err := repo.Log(&git.LogOptions{From: *headHash})
 457                 if err != nil {
 458                         makeErr(err, http.StatusInternalServerError)
 459                 }
 460                 var commits CommitIterNext
 461                 if topic == "" {
 462                         commits = repoLog
 463                 } else {
 464                         topicsCache, err := getTopicsCache(cfg, repoLog)
 465                         if err != nil {
 466                                 makeErr(err, http.StatusInternalServerError)
 467                         }
 468                         hashes := topicsCache[topic]
 469                         if hashes == nil {
 470                                 makeErr(errors.New("no posts with that topic"), http.StatusBadRequest)
 471                         }
 472                         commits = &HashesIter{hashes}
 473                 }
 474
 475                 for i := 0; i < PageEntries; i++ {
 476                         commit, err = commits.Next()
 477                         if err != nil {
 478                                 break
 479                         }
 480                         lines := msgSplit(commit.Message)
 481                         var categories []atom.Category
 482                         for _, topic := range sgblog.ParseTopics(sgblog.GetNote(
 483                                 repo, topicsTree, commit.Hash,
 484                         )) {
 485                                 categories = append(categories, atom.Category{Term: topic})
 486                         }
 487                         htmlized := make([]string, 0, len(lines))
 488                         htmlized = append(htmlized, "<pre>")
 489                         for _, l := range lines[2:] {
 490                                 htmlized = append(htmlized, lineURLize(cfg.AtomBaseURL+cfg.URLPrefix, l))
 491                         }
 492                         htmlized = append(htmlized, "</pre>")
 493                         feed.Entry = append(feed.Entry, &atom.Entry{
 494                                 Title: lines[0],
 495                                 ID:    "urn:uuid:" + bytes2uuid(commit.Hash[:]),
 496                                 Link: []atom.Link{{
 497                                         Rel:  "alternate",
 498                                         Href: cfg.AtomBaseURL + cfg.URLPrefix + "/" + commit.Hash.String(),
 499                                 }},
 500                                 Published: atom.Time(commit.Author.When),
 501                                 Updated:   atom.Time(commit.Author.When),
 502                                 Summary:   &atom.Text{Type: "text", Body: lines[0]},
 503                                 Content: &atom.Text{
 504                                         Type: "html",
 505                                         Body: strings.Join(htmlized, "\n"),
 506                                 },
 507                                 Category: categories,
 508                         })
 509                 }
 510                 data, err := xml.MarshalIndent(&feed, "", "  ")
 511                 if err != nil {
 512                         makeErr(err, http.StatusInternalServerError)
 513                 }
 514                 out.Write([]byte(xml.Header))
 515                 out.Write(data)
 516                 goto AtomFinish
 517         } else if pathInfo == "/"+AtomCommentsFeed {
 518                 commit, err := repo.CommitObject(commentsRef.Hash())
 519                 if err != nil {
 520                         makeErr(err, http.StatusInternalServerError)
 521                 }
 522                 etagHash.Write([]byte("ATOM COMMENTS"))
 523                 etagHash.Write(commit.Hash[:])
 524                 checkETag(etagHash)
 525                 idHasher, err := blake2b.New256(nil)
 526                 if err != nil {
 527                         panic(err)
 528                 }
 529                 idHasher.Write([]byte("ATOM COMMENTS"))
 530                 idHasher.Write([]byte(cfg.AtomId))
 531                 feed := atom.Feed{
 532                         Title:   cfg.Title + " comments",
 533                         ID:      "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 534                         Updated: atom.Time(commit.Author.When),
 535                         Link: []atom.Link{{
 536                                 Rel:  "self",
 537                                 Href: cfg.AtomBaseURL + cfg.URLPrefix + "/" + AtomCommentsFeed,
 538                         }},
 539                         Author: &atom.Person{Name: cfg.AtomAuthor},
 540                 }
 541                 repoLog, err := repo.Log(&git.LogOptions{From: commentsRef.Hash()})
 542                 if err != nil {
 543                         makeErr(err, http.StatusInternalServerError)
 544                 }
 545                 for i := 0; i < PageEntries; i++ {
 546                         commit, err = repoLog.Next()
 547                         if err != nil {
 548                                 break
 549                         }
 550                         fileStats, err := commit.Stats()
 551                         if err != nil {
 552                                 makeErr(err, http.StatusInternalServerError)
 553                         }
 554                         t, err := commit.Tree()
 555                         if err != nil {
 556                                 makeErr(err, http.StatusInternalServerError)
 557                         }
 558                         commentedHash := plumbing.NewHash(strings.ReplaceAll(
 559                                 fileStats[0].Name, "/", "",
 560                         ))
 561                         commit, err = repo.CommitObject(commentedHash)
 562                         if err != nil {
 563                                 continue
 564                         }
 565                         comments := sgblog.ParseComments(sgblog.GetNote(repo, t, commentedHash))
 566                         if len(comments) == 0 {
 567                                 continue
 568                         }
 569                         commentN := strconv.Itoa(len(comments) - 1)
 570                         lines := strings.Split(comments[len(comments)-1], "\n")
 571                         from := strings.TrimPrefix(lines[0], "From: ")
 572                         date := strings.TrimPrefix(lines[1], "Date: ")
 573                         htmlized := make([]string, 0, len(lines))
 574                         htmlized = append(htmlized, "<pre>")
 575                         for _, l := range lines[2:] {
 576                                 htmlized = append(htmlized, lineURLize(cfg.AtomBaseURL+cfg.URLPrefix, l))
 577                         }
 578                         htmlized = append(htmlized, "</pre>")
 579                         idHasher.Reset()
 580                         idHasher.Write([]byte("COMMENT"))
 581                         idHasher.Write(commit.Hash[:])
 582                         idHasher.Write([]byte(commentN))
 583                         feed.Entry = append(feed.Entry, &atom.Entry{
 584                                 Title: fmt.Sprintf(
 585                                         "Comment %s for \"%s\" by %s",
 586                                         commentN, msgSplit(commit.Message)[0], from,
 587                                 ),
 588                                 Author: &atom.Person{Name: from},
 589                                 ID:     "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 590                                 Link: []atom.Link{{
 591                                         Rel: "alternate",
 592                                         Href: strings.Join([]string{
 593                                                 cfg.AtomBaseURL, cfg.URLPrefix, "/",
 594                                                 commit.Hash.String(), "#comment", commentN,
 595                                         }, ""),
 596                                 }},
 597                                 Published: atom.TimeStr(strings.Replace(date, " ", "T", -1)),
 598                                 Updated:   atom.TimeStr(strings.Replace(date, " ", "T", -1)),
 599                                 Content: &atom.Text{
 600                                         Type: "html",
 601                                         Body: strings.Join(htmlized, "\n"),
 602                                 },
 603                         })
 604                 }
 605                 data, err := xml.MarshalIndent(&feed, "", "  ")
 606                 if err != nil {
 607                         makeErr(err, http.StatusInternalServerError)
 608                 }
 609                 out.Write([]byte(xml.Header))
 610                 out.Write(data)
 611                 goto AtomFinish
 612         } else if sha1DigestRe.MatchString(pathInfo[1:]) {
 613                 commit, err := repo.CommitObject(plumbing.NewHash(pathInfo[1 : 1+sha1.Size*2]))
 614                 if err != nil {
 615                         makeErr(err, http.StatusBadRequest)
 616                 }
 617                 for _, data := range etagHashForWeb {
 618                         etagHash.Write([]byte(data))
 619                 }
 620                 etagHash.Write([]byte("ENTRY"))
 621                 etagHash.Write(commit.Hash[:])
 622                 atomCommentsURL := strings.Join([]string{
 623                         cfg.AtomBaseURL, cfg.URLPrefix, "/",
 624                         commit.Hash.String(), "/", AtomCommentsFeed,
 625                 }, "")
 626                 commentsRaw := sgblog.GetNote(repo, commentsTree, commit.Hash)
 627                 etagHash.Write(commentsRaw)
 628                 topicsRaw := sgblog.GetNote(repo, topicsTree, commit.Hash)
 629                 etagHash.Write(topicsRaw)
 630                 if strings.HasSuffix(pathInfo, AtomCommentsFeed) {
 631                         etagHash.Write([]byte("ATOM COMMENTS"))
 632                         checkETag(etagHash)
 633                         type Comment struct {
 634                                 n    string
 635                                 from string
 636                                 date string
 637                                 body []string
 638                         }
 639                         commentsRaw := sgblog.ParseComments(commentsRaw)
 640                         var toSkip int
 641                         if len(commentsRaw) > PageEntries {
 642                                 toSkip = len(commentsRaw) - PageEntries
 643                         }
 644                         comments := make([]Comment, 0, len(commentsRaw)-toSkip)
 645                         for i := len(commentsRaw) - 1; i >= toSkip; i-- {
 646                                 lines := strings.Split(commentsRaw[i], "\n")
 647                                 from := strings.TrimPrefix(lines[0], "From: ")
 648                                 date := strings.TrimPrefix(lines[1], "Date: ")
 649                                 comments = append(comments, Comment{
 650                                         n:    strconv.Itoa(i),
 651                                         from: from,
 652                                         date: strings.Replace(date, " ", "T", 1),
 653                                         body: lines[3:],
 654                                 })
 655                         }
 656                         idHasher, err := blake2b.New256(nil)
 657                         if err != nil {
 658                                 panic(err)
 659                         }
 660                         idHasher.Write([]byte("ATOM COMMENTS"))
 661                         idHasher.Write(commit.Hash[:])
 662                         feed := atom.Feed{
 663                                 Title:  fmt.Sprintf("\"%s\" comments", msgSplit(commit.Message)[0]),
 664                                 ID:     "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 665                                 Link:   []atom.Link{{Rel: "self", Href: atomCommentsURL}},
 666                                 Author: &atom.Person{Name: cfg.AtomAuthor},
 667                         }
 668                         if len(comments) > 0 {
 669                                 feed.Updated = atom.TimeStr(comments[0].date)
 670                         } else {
 671                                 feed.Updated = atom.Time(commit.Author.When)
 672                         }
 673                         for _, comment := range comments {
 674                                 idHasher.Reset()
 675                                 idHasher.Write([]byte("COMMENT"))
 676                                 idHasher.Write(commit.Hash[:])
 677                                 idHasher.Write([]byte(comment.n))
 678                                 htmlized := make([]string, 0, len(comment.body))
 679                                 htmlized = append(htmlized, "<pre>")
 680                                 for _, l := range comment.body {
 681                                         htmlized = append(
 682                                                 htmlized,
 683                                                 lineURLize(cfg.AtomBaseURL+cfg.URLPrefix, l),
 684                                         )
 685                                 }
 686                                 htmlized = append(htmlized, "</pre>")
 687                                 feed.Entry = append(feed.Entry, &atom.Entry{
 688                                         Title:  fmt.Sprintf("Comment %s by %s", comment.n, comment.from),
 689                                         Author: &atom.Person{Name: comment.from},
 690                                         ID:     "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 691                                         Link: []atom.Link{{
 692                                                 Rel: "alternate",
 693                                                 Href: strings.Join([]string{
 694                                                         cfg.AtomBaseURL,
 695                                                         cfg.URLPrefix, "/",
 696                                                         commit.Hash.String(),
 697                                                         "#comment", comment.n,
 698                                                 }, ""),
 699                                         }},
 700                                         Published: atom.TimeStr(
 701                                                 strings.Replace(comment.date, " ", "T", -1),
 702                                         ),
 703                                         Updated: atom.TimeStr(
 704                                                 strings.Replace(comment.date, " ", "T", -1),
 705                                         ),
 706                                         Content: &atom.Text{
 707                                                 Type: "html",
 708                                                 Body: strings.Join(htmlized, "\n"),
 709                                         },
 710                                 })
 711                         }
 712                         data, err := xml.MarshalIndent(&feed, "", "  ")
 713                         if err != nil {
 714                                 makeErr(err, http.StatusInternalServerError)
 715                         }
 716                         out.Write([]byte(xml.Header))
 717                         out.Write(data)
 718                         goto AtomFinish
 719                 }
 720                 notesRaw := sgblog.GetNote(repo, notesTree, commit.Hash)
 721                 etagHash.Write(notesRaw)
 722                 checkETag(etagHash)
 723
 724                 lines := msgSplit(commit.Message)
 725                 title := lines[0]
 726                 when := commit.Author.When.Format(sgblog.WhenFmt)
 727                 var parent string
 728                 if len(commit.ParentHashes) > 0 {
 729                         parent = commit.ParentHashes[0].String()
 730                 }
 731                 commentsParsed := sgblog.ParseComments(commentsRaw)
 732                 comments := make([]CommentEntry, 0, len(commentsParsed))
 733                 for _, comment := range commentsParsed {
 734                         lines := strings.Split(comment, "\n")
 735                         comments = append(comments, CommentEntry{lines[:3], lines[3:]})
 736                 }
 737                 var notesLines []string
 738                 if len(notesRaw) > 0 {
 739                         notesLines = strings.Split(string(notesRaw), "\n")
 740                 }
 741
 742                 os.Stdout.Write([]byte(startHeader(etagHash, gzipWriter != nil)))
 743                 err = TmplHTMLEntry.Execute(out, struct {
 744                         T               *spreak.Localizer
 745                         Version         string
 746                         Cfg             *Cfg
 747                         Title           string
 748                         TitleEscaped    string
 749                         When            string
 750                         AtomCommentsURL string
 751                         Parent          string
 752                         Commit          *object.Commit
 753                         Lines           []string
 754                         NoteLines       []string
 755                         Comments        []CommentEntry
 756                         Topics          []string
 757                 }{
 758                         T:               localizer,
 759                         Version:         sgblog.Version,
 760                         Cfg:             cfg,
 761                         Title:           title,
 762                         TitleEscaped:    url.PathEscape(fmt.Sprintf("Re: %s (%s)", title, commit.Hash)),
 763                         When:            when,
 764                         AtomCommentsURL: atomCommentsURL,
 765                         Parent:          parent,
 766                         Commit:          commit,
 767                         Lines:           lines[2:],
 768                         NoteLines:       notesLines,
 769                         Comments:        comments,
 770                         Topics:          sgblog.ParseTopics(topicsRaw),
 771                 })
 772                 if err != nil {
 773                         makeErr(err, http.StatusInternalServerError)
 774                 }
 775         } else {
 776                 makeErr(errors.New("unknown URL action"), http.StatusNotFound)
 777         }
 778         out.Write([]byte("</body></html>\n"))
 779         if gzipWriter != nil {
 780                 gzipWriter.Close()
 781         }
 782         os.Stdout.Write(outBuf.Bytes())
 783         return
 784
 785 AtomFinish:
 786         os.Stdout.WriteString("Content-Type: application/atom+xml; charset=utf-8\n")
 787         os.Stdout.WriteString("ETag: " + etagString(etagHash) + "\n")
 788         if gzipWriter != nil {
 789                 os.Stdout.WriteString("Content-Encoding: gzip\n")
 790                 gzipWriter.Close()
 791         }
 792         os.Stdout.WriteString("\n")
 793         os.Stdout.Write(outBuf.Bytes())
 794 }