cmd/sgblog/http.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         "bytes"
  22         "compress/gzip"
  23         "crypto/sha1"
  24         "encoding/hex"
  25         "encoding/xml"
  26         "errors"
  27         "fmt"
  28         "hash"
  29         "html"
  30         "io"
  31         "log"
  32         "net/url"
  33         "os"
  34         "strconv"
  35         "strings"
  36         "text/template"
  37
  38         "github.com/go-git/go-git/v5"
  39         "github.com/go-git/go-git/v5/plumbing"
  40         "github.com/go-git/go-git/v5/plumbing/object"
  41         "go.stargrave.org/sgblog"
  42         "go.stargrave.org/sgblog/cmd/sgblog/atom"
  43         "golang.org/x/crypto/blake2b"
  44 )
  45
  46 const (
  47         AtomPostsFeed    = "feed.atom"
  48         AtomCommentsFeed = "comments.atom"
  49         TmplHTMLIndex    = `<html>
  50 <head>
  51         <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  52         <meta name="generator" content="SGBlog {{.Version}}">
  53         <title>{{.Cfg.Title}} {{if .Topic}}(topic: {{.Topic}}) {{end}}({{.Offset}}-{{.OffsetNext}})</title>
  54         {{with .Cfg.CSS}}<link rel="stylesheet" type="text/css" href="{{.}}">{{end}}
  55         {{with .Cfg.Webmaster}}<link rev="made" href="mailto:{{.}}">{{end}}
  56         {{range .Cfg.GitURLs}}<link rel="vcs-git" href="{{.}}" title="Git repository">{{end}}
  57         <link rel="top" href="{{.Cfg.URLPrefix}}/" title="top">
  58         <link rel="alternate" title="Posts feed" href="{{.Cfg.AtomBaseURL}}{{.Cfg.URLPrefix}}/{{.AtomPostsFeed}}{{if .Topic}}?topic={{.Topic}}{{end}}" type="application/atom+xml">
  59         {{if .CommentsEnabled}}<link rel="alternate" title="Comments feed" href="{{.Cfg.AtomBaseURL}}{{.Cfg.URLPrefix}}/{{.AtomCommentsFeed}}" type="application/atom+xml">{{end}}
  60         {{if .Offset}}<link rel="prev" href="{{.Cfg.URLPrefix}}/?offset={{.OffsetPrev}}{{if .Topic}}&topic={{.Topic}}{{end}}" title="prev">{{end}}
  61         {{if not .LogEnded}}<link rel="next" href="{{.Cfg.URLPrefix}}/?offset={{.OffsetNext}}{{if .Topic}}&topic={{.Topic}}{{end}}" title="next">{{end}}
  62 </head>
  63 <body>
  64 {{with .Cfg.AboutURL}}[<a href="{{.}}">about</a>]{{end}}
  65 {{block "links" .}}
  66 {{if .Offset}}[<a href="{{.Cfg.URLPrefix}}/?offset={{.OffsetPrev}}{{if .Topic}}&topic={{.Topic}}{{end}}">prev</a>]{{end}}
  67 {{if not .LogEnded}}[<a href="{{.Cfg.URLPrefix}}/?offset={{.OffsetNext}}{{if .Topic}}&topic={{.Topic}}{{end}}">next</a>]{{end}}
  68 {{end}}
  69 {{- $Cfg := .Cfg -}}
  70 {{if .Topics}}<hr/>
  71 Topics: [<tt><a href="{{$Cfg.URLPrefix}}/">ALL</a></tt>]
  72 {{range .Topics}}[<tt><a href="{{$Cfg.URLPrefix}}?topic={{.}}">{{.}}</a></tt>]
  73 {{end}}
  74 {{end}}
  75 {{- $TopicsEnabled := .TopicsEnabled -}}
  76 {{- $datePrev := "0001-01-01" -}}
  77 <table border=1>
  78 <tr>
  79         <th>N</th><th>When</th><th>Title</th>
  80         <th size="5%"><a title="Lines">L</a></th>
  81         <th size="5%"><a title="Comments">C</a></th>
  82         <th>Linked to</th>
  83         {{if .TopicsEnabled}}<th>Topics</th>{{end}}
  84 </tr>
  85 {{range .Entries -}}
  86 {{- $dateCur := .Commit.Author.When.Format "2006-01-02" -}}
  87 {{- if ne $dateCur $datePrev -}}
  88         <tr><td colspan={{if $TopicsEnabled}}7{{else}}7{{end}}><center><tt>{{$dateCur}}</tt></center></td></tr>
  89         {{- $datePrev = $dateCur -}}
  90 {{- end -}}
  91 <tr>
  92         <td>{{.Num}}</td>
  93         <td><tt>{{.Commit.Author.When.Format "15:04"}}</tt></td>
  94         <td><a href="{{$Cfg.URLPrefix}}/{{.Commit.Hash.String}}">{{.Title}}</a></td>
  95         <td>{{.LinesNum}}</td>
  96         <td>{{if .CommentsNum}}{{.CommentsNum}}{{else}}&nbsp;{{end}}</td>
  97         <td>{{if .DomainURLs}}{{range .DomainURLs}} {{.}} {{end}}{{else}}&nbsp;{{end}}</td>
  98         {{if $TopicsEnabled}}<td>{{if .Topics}}{{range .Topics}} <a href="{{$Cfg.URLPrefix}}/?topic={{.}}">{{.}}</a> {{end}}{{else}}&nbsp;{{end}}</td>{{end}}
  99 </tr>
 100 {{end}}</table>
 101 {{template "links" .}}
 102 </body>
 103 </html>
 104 `
 105         TmplHTMLEntry = `{{$Cfg := .Cfg}}<html>
 106 <head>
 107         <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 108         <meta name="generator" content="SGBlog {{.Version}}">
 109         <title>{{.Title}} ({{.When}})</title>
 110         {{with .Cfg.CSS}}<link rel="stylesheet" type="text/css" href="{{.}}">{{end}}
 111         {{with .Cfg.Webmaster}}<link rev="made" href="mailto:{{.}}">{{end -}}
 112         {{- range .Cfg.GitURLs}}
 113         <link rel="vcs-git" href="{{.}}" title="Git repository">{{end}}
 114         <link rel="top" href="{{.Cfg.URLPrefix}}/" title="top">
 115         <link rel="alternate" title="Comments feed" href="{{.AtomCommentsURL}}" type="application/atom+xml">
 116         {{if .Parent}}<link rel="prev" href="{{.Cfg.URLPrefix}}/{{.Parent}}" title="prev">{{end}}
 117 </head>
 118 <body>
 119 {{with .Cfg.AboutURL}}[<a href="{{.}}">about</a>]{{end}}
 120 [<a href="{{.Cfg.URLPrefix}}/">index</a>]
 121 {{if .Parent}}[<a href="{{.Cfg.URLPrefix}}/{{.Parent}}">prev</a>]{{end}}
 122 [<tt><a title="When">{{.When}}</a></tt>]
 123 [<tt><a title="What">{{.Commit.Hash.String}}</a></tt>]
 124
 125 {{if .Topics}}
 126 <hr/>
 127 Topics: {{range .Topics}}[<tt><a href="{{$Cfg.URLPrefix}}?topic={{.}}">{{.}}</a></tt>]{{end}}
 128 {{end}}
 129
 130 <hr/>
 131 <h2>{{.Title}}</h2>
 132 <pre>
 133 {{range .Lines}}{{. | lineURLize $Cfg.URLPrefix}}
 134 {{end}}</pre>
 135 <hr/>
 136
 137 {{if .NoteLines}}Note:<pre>
 138 {{range .NoteLines}}{{. | lineURLize $Cfg.URLPrefix}}
 139 {{end}}</pre>
 140 <hr/>{{end}}
 141
 142 {{if .Cfg.CommentsEmail}}[<a href="mailto:{{.Cfg.CommentsEmail}}?subject={{.TitleEscaped}}">leave comment</a>]{{end}}
 143
 144 <dl>{{range $idx, $comment := .Comments}}
 145 <dt><a name="comment{{$idx}}"><a href="#comment{{$idx}}">comment {{$idx}}</a>:</dt>
 146 <dd><pre>
 147 {{range $comment.HeaderLines}}{{.}}
 148 {{end}}{{range $comment.BodyLines}}{{. | lineURLize $Cfg.URLPrefix}}
 149 {{end}}</pre></dd>
 150 {{end}}</dl>
 151
 152 </body>
 153 </html>
 154 `
 155 )
 156
 157 var (
 158         renderableSchemes = map[string]struct{}{
 159                 "ftp":    {},
 160                 "gopher": {},
 161                 "http":   {},
 162                 "https":  {},
 163                 "telnet": {},
 164         }
 165 )
 166
 167 type TableEntry struct {
 168         Commit      *object.Commit
 169         CommentsRaw []byte
 170         TopicsRaw   []byte
 171         Num         int
 172         Title       string
 173         LinesNum    int
 174         CommentsNum int
 175         DomainURLs  []string
 176         Topics      []string
 177 }
 178
 179 type CommentEntry struct {
 180         HeaderLines []string
 181         BodyLines   []string
 182 }
 183
 184 func makeA(href, text string) string {
 185         return `<a href="` + href + `">` + text + `</a>`
 186 }
 187
 188 func etagString(etag hash.Hash) string {
 189         return `"` + hex.EncodeToString(etag.Sum(nil)) + `"`
 190 }
 191
 192 func urlParse(what string) *url.URL {
 193         if u, err := url.ParseRequestURI(what); err == nil {
 194                 if _, exists := renderableSchemes[u.Scheme]; exists {
 195                         return u
 196                 }
 197         }
 198         return nil
 199 }
 200
 201 func lineURLize(urlPrefix, line string) string {
 202         cols := strings.Split(html.EscapeString(line), " ")
 203         for i, col := range cols {
 204                 if u := urlParse(col); u != nil {
 205                         cols[i] = makeA(col, col)
 206                         continue
 207                 }
 208                 cols[i] = sha1DigestRe.ReplaceAllString(col, makeA(urlPrefix+"/$1", "$1"))
 209         }
 210         return strings.Join(cols, " ")
 211 }
 212
 213 func lineURLizeInTemplate(urlPrefix, line interface{}) string {
 214         return lineURLize(urlPrefix.(string), line.(string))
 215 }
 216
 217 func startHeader(etag hash.Hash, gziped bool) string {
 218         lines := []string{
 219                 "Content-Type: text/html; charset=UTF-8",
 220                 "ETag: " + etagString(etag),
 221         }
 222         if gziped {
 223                 lines = append(lines, "Content-Encoding: gzip")
 224         }
 225         lines = append(lines, "")
 226         lines = append(lines, "")
 227         return strings.Join(lines, "\n")
 228 }
 229
 230 func makeErr(err error) {
 231         fmt.Print("Content-Type: text/plain; charset=UTF-8\n\n")
 232         fmt.Println(err)
 233         panic(err)
 234 }
 235
 236 func checkETag(etag hash.Hash) {
 237         ifNoneMatch := os.Getenv("HTTP_IF_NONE_MATCH")
 238         if ifNoneMatch != "" && ifNoneMatch == etagString(etag) {
 239                 fmt.Printf("Status: 304\nETag: %s\n\n", ifNoneMatch)
 240                 os.Exit(0)
 241         }
 242 }
 243
 244 func bytes2uuid(b []byte) string {
 245         raw := new([16]byte)
 246         copy(raw[:], b)
 247         raw[6] = (raw[6] & 0x0F) | uint8(4<<4) // version 4
 248         return fmt.Sprintf("%x-%x-%x-%x-%x", raw[0:4], raw[4:6], raw[6:8], raw[8:10], raw[10:])
 249 }
 250
 251 type CommitIterNext interface {
 252         Next() (*object.Commit, error)
 253 }
 254
 255 func serveHTTP() {
 256         cfgPath := os.Getenv("SGBLOG_CFG")
 257         if cfgPath == "" {
 258                 log.Fatalln("SGBLOG_CFG is not set")
 259         }
 260         cfg, err := readCfg(cfgPath)
 261         if err != nil {
 262                 log.Fatalln(err)
 263         }
 264
 265         pathInfo, exists := os.LookupEnv("PATH_INFO")
 266         if !exists {
 267                 pathInfo = "/"
 268         }
 269         queryValues, err := url.ParseQuery(os.Getenv("QUERY_STRING"))
 270         if err != nil {
 271                 makeErr(err)
 272         }
 273
 274         etagHash, err := blake2b.New256(nil)
 275         if err != nil {
 276                 panic(err)
 277         }
 278         for _, s := range []string{
 279                 "SGBLOG",
 280                 sgblog.Version,
 281                 cfg.GitPath,
 282                 cfg.Branch,
 283                 cfg.Title,
 284                 cfg.URLPrefix,
 285                 cfg.AtomBaseURL,
 286                 cfg.AtomId,
 287                 cfg.AtomAuthor,
 288         } {
 289                 if _, err = etagHash.Write([]byte(s)); err != nil {
 290                         panic(err)
 291                 }
 292         }
 293         etagHashForWeb := []string{
 294                 cfg.CSS,
 295                 cfg.Webmaster,
 296                 cfg.AboutURL,
 297                 cfg.CommentsNotesRef,
 298                 cfg.CommentsEmail,
 299         }
 300         for _, gitURL := range cfg.GitURLs {
 301                 etagHashForWeb = append(etagHashForWeb, gitURL)
 302         }
 303
 304         headHash, err := initRepo(cfg)
 305         if err != nil {
 306                 makeErr(err)
 307         }
 308
 309         if notes, err := repo.Notes(); err == nil {
 310                 var notesRef *plumbing.Reference
 311                 var commentsRef *plumbing.Reference
 312                 notes.ForEach(func(ref *plumbing.Reference) error {
 313                         switch string(ref.Name()) {
 314                         case "refs/notes/commits":
 315                                 notesRef = ref
 316                         case cfg.CommentsNotesRef:
 317                                 commentsRef = ref
 318                         }
 319                         return nil
 320                 })
 321                 if notesRef != nil {
 322                         if commentsCommit, err := repo.CommitObject(notesRef.Hash()); err == nil {
 323                                 notesTree, _ = commentsCommit.Tree()
 324                         }
 325                 }
 326                 if commentsRef != nil {
 327                         if commentsCommit, err := repo.CommitObject(commentsRef.Hash()); err == nil {
 328                                 commentsTree, _ = commentsCommit.Tree()
 329                         }
 330                 }
 331         }
 332
 333         var outBuf bytes.Buffer
 334         var out io.Writer
 335         out = &outBuf
 336         var gzipWriter *gzip.Writer
 337         acceptEncoding := os.Getenv("HTTP_ACCEPT_ENCODING")
 338         for _, encoding := range strings.Split(acceptEncoding, ", ") {
 339                 if encoding == "gzip" {
 340                         gzipWriter = gzip.NewWriter(&outBuf)
 341                         out = gzipWriter
 342                 }
 343         }
 344
 345         if pathInfo == "/" {
 346                 offset := 0
 347                 if offsetRaw, exists := queryValues["offset"]; exists {
 348                         offset, err = strconv.Atoi(offsetRaw[0])
 349                         if err != nil {
 350                                 makeErr(err)
 351                         }
 352                 }
 353                 repoLog, err := repo.Log(&git.LogOptions{From: *headHash})
 354                 if err != nil {
 355                         makeErr(err)
 356                 }
 357                 topicsCache, err := getTopicsCache(cfg, repoLog)
 358                 if err != nil {
 359                         makeErr(err)
 360                 }
 361                 repoLog, err = repo.Log(&git.LogOptions{From: *headHash})
 362                 if err != nil {
 363                         makeErr(err)
 364                 }
 365
 366                 commitN := 0
 367                 var commits CommitIterNext
 368                 var topic string
 369                 if t, exists := queryValues["topic"]; exists {
 370                         topic = t[0]
 371                         hashes := topicsCache[topic]
 372                         if hashes == nil {
 373                                 makeErr(errors.New("no posts with that topic"))
 374                         }
 375                         if len(hashes) > offset {
 376                                 hashes = hashes[offset:]
 377                                 commitN += offset
 378                         }
 379                         commits = &HashesIter{hashes}
 380                 } else {
 381                         for i := 0; i < offset; i++ {
 382                                 if _, err = repoLog.Next(); err != nil {
 383                                         break
 384                                 }
 385                                 commitN++
 386                         }
 387                         commits = repoLog
 388                 }
 389
 390                 entries := make([]TableEntry, 0, PageEntries)
 391                 logEnded := false
 392                 for _, data := range etagHashForWeb {
 393                         etagHash.Write([]byte(data))
 394                 }
 395                 etagHash.Write([]byte("INDEX"))
 396                 etagHash.Write([]byte(topic))
 397                 for i := 0; i < PageEntries; i++ {
 398                         commit, err := commits.Next()
 399                         if err != nil {
 400                                 logEnded = true
 401                                 break
 402                         }
 403                         etagHash.Write(commit.Hash[:])
 404                         commentsRaw := sgblog.GetNote(repo, commentsTree, commit.Hash)
 405                         etagHash.Write(commentsRaw)
 406                         topicsRaw := sgblog.GetNote(repo, topicsTree, commit.Hash)
 407                         etagHash.Write(topicsRaw)
 408                         entries = append(entries, TableEntry{
 409                                 Commit:      commit,
 410                                 CommentsRaw: commentsRaw,
 411                                 TopicsRaw:   topicsRaw,
 412                         })
 413                 }
 414                 checkETag(etagHash)
 415
 416                 for i, entry := range entries {
 417                         commitN++
 418                         entry.Num = commitN
 419                         lines := msgSplit(entry.Commit.Message)
 420                         entry.Title = lines[0]
 421                         entry.LinesNum = len(lines) - 2
 422                         for _, line := range lines[2:] {
 423                                 u := urlParse(line)
 424                                 if u == nil {
 425                                         break
 426                                 }
 427                                 entry.DomainURLs = append(entry.DomainURLs, makeA(line, u.Host))
 428                         }
 429                         entry.CommentsNum = len(sgblog.ParseComments(entry.CommentsRaw))
 430                         entry.Topics = sgblog.ParseTopics(entry.TopicsRaw)
 431                         entries[i] = entry
 432                 }
 433                 offsetPrev := offset - PageEntries
 434                 if offsetPrev < 0 {
 435                         offsetPrev = 0
 436                 }
 437                 tmpl := template.Must(template.New("index").Parse(TmplHTMLIndex))
 438                 os.Stdout.Write([]byte(startHeader(etagHash, gzipWriter != nil)))
 439                 err = tmpl.Execute(out, struct {
 440                         Version          string
 441                         Cfg              *Cfg
 442                         Topic            string
 443                         TopicsEnabled    bool
 444                         Topics           []string
 445                         CommentsEnabled  bool
 446                         AtomPostsFeed    string
 447                         AtomCommentsFeed string
 448                         Offset           int
 449                         OffsetPrev       int
 450                         OffsetNext       int
 451                         LogEnded         bool
 452                         Entries          []TableEntry
 453                 }{
 454                         Version:          sgblog.Version,
 455                         Cfg:              cfg,
 456                         Topic:            topic,
 457                         TopicsEnabled:    topicsTree != nil,
 458                         Topics:           topicsCache.Topics(),
 459                         CommentsEnabled:  commentsTree != nil,
 460                         AtomPostsFeed:    AtomPostsFeed,
 461                         AtomCommentsFeed: AtomCommentsFeed,
 462                         Offset:           offset,
 463                         OffsetPrev:       offsetPrev,
 464                         OffsetNext:       offset + PageEntries,
 465                         LogEnded:         logEnded,
 466                         Entries:          entries,
 467                 })
 468                 if err != nil {
 469                         makeErr(err)
 470                 }
 471         } else if pathInfo == "/"+AtomPostsFeed {
 472                 commit, err := repo.CommitObject(*headHash)
 473                 if err != nil {
 474                         makeErr(err)
 475                 }
 476
 477                 var topic string
 478                 if t, exists := queryValues["topic"]; exists {
 479                         topic = t[0]
 480                 }
 481
 482                 etagHash.Write([]byte("ATOM POSTS"))
 483                 etagHash.Write([]byte(topic))
 484                 etagHash.Write(commit.Hash[:])
 485                 checkETag(etagHash)
 486                 var title string
 487                 if topic == "" {
 488                         title = cfg.Title
 489                 } else {
 490                         title = fmt.Sprintf("%s (topic: %s)", cfg.Title, topic)
 491                 }
 492                 idHasher, err := blake2b.New256(nil)
 493                 if err != nil {
 494                         panic(err)
 495                 }
 496                 idHasher.Write([]byte("ATOM POSTS"))
 497                 idHasher.Write([]byte(cfg.AtomId))
 498                 idHasher.Write([]byte(topic))
 499                 feed := atom.Feed{
 500                         Title:   title,
 501                         ID:      "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 502                         Updated: atom.Time(commit.Author.When),
 503                         Link: []atom.Link{{
 504                                 Rel:  "self",
 505                                 Href: cfg.AtomBaseURL + cfg.URLPrefix + "/" + AtomPostsFeed,
 506                         }},
 507                         Author: &atom.Person{Name: cfg.AtomAuthor},
 508                 }
 509
 510                 repoLog, err := repo.Log(&git.LogOptions{From: *headHash})
 511                 if err != nil {
 512                         makeErr(err)
 513                 }
 514                 var commits CommitIterNext
 515                 if topic == "" {
 516                         commits = repoLog
 517                 } else {
 518                         topicsCache, err := getTopicsCache(cfg, repoLog)
 519                         if err != nil {
 520                                 makeErr(err)
 521                         }
 522                         hashes := topicsCache[topic]
 523                         if hashes == nil {
 524                                 makeErr(errors.New("no posts with that topic"))
 525                         }
 526                         commits = &HashesIter{hashes}
 527                 }
 528
 529                 for i := 0; i < PageEntries; i++ {
 530                         commit, err = commits.Next()
 531                         if err != nil {
 532                                 break
 533                         }
 534                         lines := msgSplit(commit.Message)
 535                         var categories []atom.Category
 536                         for _, topic := range sgblog.ParseTopics(sgblog.GetNote(repo, topicsTree, commit.Hash)) {
 537                                 categories = append(categories, atom.Category{Term: topic})
 538                         }
 539                         htmlized := make([]string, 0, len(lines))
 540                         htmlized = append(htmlized, "<pre>")
 541                         for _, l := range lines[2:] {
 542                                 htmlized = append(htmlized, lineURLize(cfg.AtomBaseURL+cfg.URLPrefix, l))
 543                         }
 544                         htmlized = append(htmlized, "</pre>")
 545                         feed.Entry = append(feed.Entry, &atom.Entry{
 546                                 Title: lines[0],
 547                                 ID:    "urn:uuid:" + bytes2uuid(commit.Hash[:]),
 548                                 Link: []atom.Link{{
 549                                         Rel:  "alternate",
 550                                         Href: cfg.AtomBaseURL + cfg.URLPrefix + "/" + commit.Hash.String(),
 551                                 }},
 552                                 Published: atom.Time(commit.Author.When),
 553                                 Updated:   atom.Time(commit.Author.When),
 554                                 Summary:   &atom.Text{Type: "text", Body: lines[0]},
 555                                 Content: &atom.Text{
 556                                         Type: "html",
 557                                         Body: strings.Join(htmlized, "\n"),
 558                                 },
 559                                 Category: categories,
 560                         })
 561                 }
 562                 data, err := xml.MarshalIndent(&feed, "", "  ")
 563                 if err != nil {
 564                         makeErr(err)
 565                 }
 566                 out.Write(data)
 567                 goto AtomFinish
 568         } else if pathInfo == "/"+AtomCommentsFeed {
 569                 commit, err := repo.CommitObject(commentsRef.Hash())
 570                 if err != nil {
 571                         makeErr(err)
 572                 }
 573                 etagHash.Write([]byte("ATOM COMMENTS"))
 574                 etagHash.Write(commit.Hash[:])
 575                 checkETag(etagHash)
 576                 idHasher, err := blake2b.New256(nil)
 577                 if err != nil {
 578                         panic(err)
 579                 }
 580                 idHasher.Write([]byte("ATOM COMMENTS"))
 581                 idHasher.Write([]byte(cfg.AtomId))
 582                 feed := atom.Feed{
 583                         Title:   cfg.Title + " comments",
 584                         ID:      "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 585                         Updated: atom.Time(commit.Author.When),
 586                         Link: []atom.Link{{
 587                                 Rel:  "self",
 588                                 Href: cfg.AtomBaseURL + cfg.URLPrefix + "/" + AtomCommentsFeed,
 589                         }},
 590                         Author: &atom.Person{Name: cfg.AtomAuthor},
 591                 }
 592                 repoLog, err := repo.Log(&git.LogOptions{From: commentsRef.Hash()})
 593                 if err != nil {
 594                         makeErr(err)
 595                 }
 596                 for i := 0; i < PageEntries; i++ {
 597                         commit, err = repoLog.Next()
 598                         if err != nil {
 599                                 break
 600                         }
 601                         fileStats, err := commit.Stats()
 602                         if err != nil {
 603                                 makeErr(err)
 604                         }
 605                         t, err := commit.Tree()
 606                         if err != nil {
 607                                 makeErr(err)
 608                         }
 609                         commentedHash := plumbing.NewHash(strings.ReplaceAll(
 610                                 fileStats[0].Name, "/", "",
 611                         ))
 612                         commit, err = repo.CommitObject(commentedHash)
 613                         if err != nil {
 614                                 continue
 615                         }
 616                         comments := sgblog.ParseComments(sgblog.GetNote(repo, t, commentedHash))
 617                         if len(comments) == 0 {
 618                                 continue
 619                         }
 620                         commentN := strconv.Itoa(len(comments) - 1)
 621                         lines := strings.Split(comments[len(comments)-1], "\n")
 622                         from := strings.TrimPrefix(lines[0], "From: ")
 623                         date := strings.TrimPrefix(lines[1], "Date: ")
 624                         htmlized := make([]string, 0, len(lines))
 625                         htmlized = append(htmlized, "<pre>")
 626                         for _, l := range lines[2:] {
 627                                 htmlized = append(htmlized, lineURLize(cfg.AtomBaseURL+cfg.URLPrefix, l))
 628                         }
 629                         htmlized = append(htmlized, "</pre>")
 630                         idHasher.Reset()
 631                         idHasher.Write([]byte("COMMENT"))
 632                         idHasher.Write(commit.Hash[:])
 633                         idHasher.Write([]byte(commentN))
 634                         feed.Entry = append(feed.Entry, &atom.Entry{
 635                                 Title: fmt.Sprintf(
 636                                         "Comment %s for \"%s\" by %s",
 637                                         commentN, msgSplit(commit.Message)[0], from,
 638                                 ),
 639                                 Author: &atom.Person{Name: from},
 640                                 ID:     "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 641                                 Link: []atom.Link{{
 642                                         Rel: "alternate",
 643                                         Href: strings.Join([]string{
 644                                                 cfg.AtomBaseURL, cfg.URLPrefix, "/",
 645                                                 commit.Hash.String(), "#comment", commentN,
 646                                         }, ""),
 647                                 }},
 648                                 Published: atom.TimeStr(date),
 649                                 Updated:   atom.TimeStr(date),
 650                                 Content: &atom.Text{
 651                                         Type: "html",
 652                                         Body: strings.Join(htmlized, "\n"),
 653                                 },
 654                         })
 655                 }
 656                 data, err := xml.MarshalIndent(&feed, "", "  ")
 657                 if err != nil {
 658                         makeErr(err)
 659                 }
 660                 out.Write(data)
 661                 goto AtomFinish
 662         } else if sha1DigestRe.MatchString(pathInfo[1:]) {
 663                 commit, err := repo.CommitObject(plumbing.NewHash(pathInfo[1 : 1+sha1.Size*2]))
 664                 if err != nil {
 665                         makeErr(err)
 666                 }
 667                 for _, data := range etagHashForWeb {
 668                         etagHash.Write([]byte(data))
 669                 }
 670                 etagHash.Write([]byte("ENTRY"))
 671                 etagHash.Write(commit.Hash[:])
 672                 atomCommentsURL := strings.Join([]string{
 673                         cfg.AtomBaseURL, cfg.URLPrefix, "/",
 674                         commit.Hash.String(), "/", AtomCommentsFeed,
 675                 }, "")
 676                 commentsRaw := sgblog.GetNote(repo, commentsTree, commit.Hash)
 677                 etagHash.Write(commentsRaw)
 678                 topicsRaw := sgblog.GetNote(repo, topicsTree, commit.Hash)
 679                 etagHash.Write(topicsRaw)
 680                 if strings.HasSuffix(pathInfo, AtomCommentsFeed) {
 681                         etagHash.Write([]byte("ATOM COMMENTS"))
 682                         checkETag(etagHash)
 683                         type Comment struct {
 684                                 n    string
 685                                 from string
 686                                 date string
 687                                 body []string
 688                         }
 689                         commentsRaw := sgblog.ParseComments(commentsRaw)
 690                         var toSkip int
 691                         if len(commentsRaw) > PageEntries {
 692                                 toSkip = len(commentsRaw) - PageEntries
 693                         }
 694                         comments := make([]Comment, 0, len(commentsRaw)-toSkip)
 695                         for i := len(commentsRaw) - 1; i >= toSkip; i-- {
 696                                 lines := strings.Split(commentsRaw[i], "\n")
 697                                 from := strings.TrimPrefix(lines[0], "From: ")
 698                                 date := strings.TrimPrefix(lines[1], "Date: ")
 699                                 comments = append(comments, Comment{
 700                                         n:    strconv.Itoa(i),
 701                                         from: from,
 702                                         date: strings.Replace(date, " ", "T", 1),
 703                                         body: lines[3:],
 704                                 })
 705                         }
 706                         idHasher, err := blake2b.New256(nil)
 707                         if err != nil {
 708                                 panic(err)
 709                         }
 710                         idHasher.Write([]byte("ATOM COMMENTS"))
 711                         idHasher.Write(commit.Hash[:])
 712                         feed := atom.Feed{
 713                                 Title:  fmt.Sprintf("\"%s\" comments", msgSplit(commit.Message)[0]),
 714                                 ID:     "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 715                                 Link:   []atom.Link{{Rel: "self", Href: atomCommentsURL}},
 716                                 Author: &atom.Person{Name: cfg.AtomAuthor},
 717                         }
 718                         if len(comments) > 0 {
 719                                 feed.Updated = atom.TimeStr(comments[0].date)
 720                         } else {
 721                                 feed.Updated = atom.Time(commit.Author.When)
 722                         }
 723                         for _, comment := range comments {
 724                                 idHasher.Reset()
 725                                 idHasher.Write([]byte("COMMENT"))
 726                                 idHasher.Write(commit.Hash[:])
 727                                 idHasher.Write([]byte(comment.n))
 728                                 htmlized := make([]string, 0, len(comment.body))
 729                                 htmlized = append(htmlized, "<pre>")
 730                                 for _, l := range comment.body {
 731                                         htmlized = append(
 732                                                 htmlized,
 733                                                 lineURLize(cfg.AtomBaseURL+cfg.URLPrefix, l),
 734                                         )
 735                                 }
 736                                 htmlized = append(htmlized, "</pre>")
 737                                 feed.Entry = append(feed.Entry, &atom.Entry{
 738                                         Title:  fmt.Sprintf("Comment %s by %s", comment.n, comment.from),
 739                                         Author: &atom.Person{Name: comment.from},
 740                                         ID:     "urn:uuid:" + bytes2uuid(idHasher.Sum(nil)),
 741                                         Link: []atom.Link{{
 742                                                 Rel: "alternate",
 743                                                 Href: strings.Join([]string{
 744                                                         cfg.AtomBaseURL,
 745                                                         cfg.URLPrefix, "/",
 746                                                         commit.Hash.String(),
 747                                                         "#comment", comment.n,
 748                                                 }, ""),
 749                                         }},
 750                                         Published: atom.TimeStr(comment.date),
 751                                         Updated:   atom.TimeStr(comment.date),
 752                                         Content: &atom.Text{
 753                                                 Type: "html",
 754                                                 Body: strings.Join(htmlized, "\n"),
 755                                         },
 756                                 })
 757                         }
 758                         data, err := xml.MarshalIndent(&feed, "", "  ")
 759                         if err != nil {
 760                                 makeErr(err)
 761                         }
 762                         out.Write(data)
 763                         goto AtomFinish
 764                 }
 765                 notesRaw := sgblog.GetNote(repo, notesTree, commit.Hash)
 766                 etagHash.Write(notesRaw)
 767                 checkETag(etagHash)
 768
 769                 lines := msgSplit(commit.Message)
 770                 title := lines[0]
 771                 when := commit.Author.When.Format(sgblog.WhenFmt)
 772                 var parent string
 773                 if len(commit.ParentHashes) > 0 {
 774                         parent = commit.ParentHashes[0].String()
 775                 }
 776                 commentsParsed := sgblog.ParseComments(commentsRaw)
 777                 comments := make([]CommentEntry, 0, len(commentsParsed))
 778                 for _, comment := range commentsParsed {
 779                         lines := strings.Split(comment, "\n")
 780                         comments = append(comments, CommentEntry{lines[:3], lines[3:]})
 781                 }
 782                 var notesLines []string
 783                 if len(notesRaw) > 0 {
 784                         notesLines = strings.Split(string(notesRaw), "\n")
 785                 }
 786
 787                 tmpl := template.New("entry")
 788                 tmpl = tmpl.Funcs(template.FuncMap{"lineURLize": lineURLizeInTemplate})
 789                 tmpl = template.Must(tmpl.Parse(TmplHTMLEntry))
 790                 os.Stdout.Write([]byte(startHeader(etagHash, gzipWriter != nil)))
 791                 err = tmpl.Execute(out, struct {
 792                         Version         string
 793                         Cfg             *Cfg
 794                         Title           string
 795                         TitleEscaped    string
 796                         When            string
 797                         AtomCommentsURL string
 798                         Parent          string
 799                         Commit          *object.Commit
 800                         Lines           []string
 801                         NoteLines       []string
 802                         Comments        []CommentEntry
 803                         Topics          []string
 804                 }{
 805                         Version:         sgblog.Version,
 806                         Cfg:             cfg,
 807                         Title:           title,
 808                         TitleEscaped:    url.PathEscape(fmt.Sprintf("Re: %s (%s)", title, commit.Hash)),
 809                         When:            when,
 810                         AtomCommentsURL: atomCommentsURL,
 811                         Parent:          parent,
 812                         Commit:          commit,
 813                         Lines:           lines[2:],
 814                         NoteLines:       notesLines,
 815                         Comments:        comments,
 816                         Topics:          sgblog.ParseTopics(topicsRaw),
 817                 })
 818                 if err != nil {
 819                         makeErr(err)
 820                 }
 821         } else {
 822                 makeErr(errors.New("unknown URL action"))
 823         }
 824         out.Write([]byte("</body></html>\n"))
 825         if gzipWriter != nil {
 826                 gzipWriter.Close()
 827         }
 828         os.Stdout.Write(outBuf.Bytes())
 829         return
 830
 831 AtomFinish:
 832         os.Stdout.WriteString("Content-Type: application/atom+xml; charset=UTF-8\n")
 833         os.Stdout.WriteString("ETag: " + etagString(etagHash) + "\n")
 834         if gzipWriter != nil {
 835                 os.Stdout.WriteString("Content-Encoding: gzip\n")
 836                 gzipWriter.Close()
 837         }
 838         os.Stdout.WriteString("\n")
 839         os.Stdout.Write(outBuf.Bytes())
 840 }