Implement RSS, Atom and JSON feeds and add a new flag

flag.go

@@ -10,8 +10,9 @@ import (
 )
 
 func init() {
-	flag.StringVar(&util.ServerPort, "port", "1737", "Port to serve the wiki at")
-	flag.StringVar(&util.HomePage, "home", "home", "The home page")
+	flag.StringVar(&util.URL, "url", "http://0.0.0.0:$port", "URL at which your wiki can be found. Used to generate feeds")
+	flag.StringVar(&util.ServerPort, "port", "1737", "Port to serve the wiki at using HTTP")
+	flag.StringVar(&util.HomePage, "home", "home", "The home page name")
 	flag.StringVar(&util.SiteTitle, "title", "🍄", "How to call your wiki in the navititle")
 	flag.StringVar(&util.UserTree, "user-tree", "u", "Hypha which is a superhypha of all user pages")
 	flag.StringVar(&util.AuthMethod, "auth-method", "none", "What auth method to use. Variants: \"none\", \"fixed\"")
@@ -34,6 +35,10 @@ func parseCliArgs() {
 		log.Fatal(err)
 	}
 
+	if util.URL == "http://0.0.0.0:$port" {
+		util.URL = "http://0.0.0.0:" + util.ServerPort
+	}
+
 	if !isCanonicalName(util.HomePage) {
 		log.Fatal("Error: you must use a proper name for the homepage")
 	}

go.mod

@@ -4,5 +4,6 @@ go 1.14
 
 require (
 	github.com/adrg/xdg v0.2.2
+	github.com/gorilla/feeds v1.1.1
 	github.com/valyala/quicktemplate v1.6.3
 )

go.sum

@@ -2,6 +2,8 @@ github.com/adrg/xdg v0.2.2 h1:A7ZHKRz5KGOLJX/bg7IPzStryhvCzAE1wX+KWawPiAo=
 github.com/adrg/xdg v0.2.2/go.mod h1:7I2hH/IT30IsupOpKZ5ue7/qNi3CoKzD6tL3HwpaRMQ=
 github.com/andybalholm/brotli v1.0.0/go.mod h1:loMXtMfwqflxFJPmdbJO0a3KNoPuLBgiu3qAvBg8x/Y=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/gorilla/feeds v1.1.1 h1:HwKXxqzcRNg9to+BbvJog4+f3s/xzvtZXICcQGutYfY=
+github.com/gorilla/feeds v1.1.1/go.mod h1:Nk0jZrvPFZX1OBe5NPiddPw7CfwF6Q9eqzaBbaightA=
 github.com/klauspost/compress v1.10.7/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
 github.com/klauspost/compress v1.11.0/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=

history/history.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"os/exec"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -13,6 +14,8 @@ import (
 	"github.com/bouncepaw/mycorrhiza/util"
 )
 
+var renameMsgPattern = regexp.MustCompile(`^Rename ‘(.*)’ to ‘.*’`)
+
 // Start initializes git credentials.
 func Start(wikiDir string) {
 	_, err := gitsh("config", "user.name", "wikimind")
@@ -31,6 +34,42 @@ type Revision struct {
 	Username          string
 	Time              time.Time
 	Message           string
+	hyphaeAffectedBuf []string
+}
+
+// determine what hyphae were affected by this revision
+func (rev *Revision) hyphaeAffected() (hyphae []string) {
+	if nil != rev.hyphaeAffectedBuf {
+		return rev.hyphaeAffectedBuf
+	}
+	hyphae = make([]string, 0)
+	var (
+		// List of files affected by this revision, one per line.
+		out, err = gitsh("diff-tree", "--no-commit-id", "--name-only", "-r", rev.Hash)
+		// set is used to determine if a certain hypha has been already noted (hyphae are stored in 2 files at most currently).
+		set       = make(map[string]bool)
+		isNewName = func(hyphaName string) bool {
+			if _, present := set[hyphaName]; present {
+				return false
+			}
+			set[hyphaName] = true
+			return true
+		}
+	)
+	if err != nil {
+		return hyphae
+	}
+	for _, filename := range strings.Split(out.String(), "\n") {
+		if strings.IndexRune(filename, '.') >= 0 {
+			dotPos := strings.LastIndexByte(filename, '.')
+			hyphaName := string([]byte(filename)[0:dotPos]) // is it safe?
+			if isNewName(hyphaName) {
+				hyphae = append(hyphae, hyphaName)
+			}
+		}
+	}
+	rev.hyphaeAffectedBuf = hyphae
+	return hyphae
 }
 
 // TimeString returns a human readable time representation.
@@ -40,42 +79,38 @@ func (rev Revision) TimeString() string {
 
 // HyphaeLinks returns a comma-separated list of hyphae that were affected by this revision as HTML string.
 func (rev Revision) HyphaeLinks() (html string) {
-	// diff-tree --no-commit-id --name-only -r
-	var (
-		// List of files affected by this revision, one per line.
-		out, err = gitsh("diff-tree", "--no-commit-id", "--name-only", "-r", rev.Hash)
-		// set is used to determine if a certain hypha has been already noted (hyphae are stored in 2 files at most).
-		set       = make(map[string]bool)
-		isNewName = func(hyphaName string) bool {
-			if _, present := set[hyphaName]; present {
-				return false
-			} else {
-				set[hyphaName] = true
-				return true
-			}
-		}
-	)
-	if err != nil {
-		return ""
-	}
-	for _, filename := range strings.Split(out.String(), "\n") {
-		// If filename has an ampersand:
-		if strings.IndexRune(filename, '.') >= 0 {
-			// Remove ampersanded suffix from filename:
-			ampersandPos := strings.LastIndexByte(filename, '.')
-			hyphaName := string([]byte(filename)[0:ampersandPos]) // is it safe?
-			if isNewName(hyphaName) {
-				// Entries are separated by commas
-				if len(set) > 1 {
+	hyphae := rev.hyphaeAffected()
+	for i, hyphaName := range hyphae {
+		if i > 0 {
 			html += `<span aria-hidden="true">, </span>`
 		}
 		html += fmt.Sprintf(`<a href="/page/%[1]s">%[1]s</a>`, hyphaName)
 	}
-		}
-	}
 	return html
 }
 
+func (rev *Revision) descriptionForFeed() (html string) {
+	return fmt.Sprintf(
+		`<p>%s</p>
+<p><b>Hyphae affected:</b> %s</p>`, rev.Message, rev.HyphaeLinks())
+}
+
+// Try and guess what link is the most important by looking at the message.
+func (rev *Revision) bestLink() string {
+	var (
+		revs      = rev.hyphaeAffected()
+		renameRes = renameMsgPattern.FindStringSubmatch(rev.Message)
+	)
+	switch {
+	case renameRes != nil:
+		return "/page/" + renameRes[1]
+	case len(revs) == 0:
+		return ""
+	default:
+		return "/page/" + revs[0]
+	}
+}
+
 func (rev Revision) RecentChangesEntry() (html string) {
 	if user.AuthUsed && rev.Username != "anon" {
 		return fmt.Sprintf(`

history/information.go

@@ -11,8 +11,56 @@ import (
 
 	"github.com/bouncepaw/mycorrhiza/templates"
 	"github.com/bouncepaw/mycorrhiza/util"
+	"github.com/gorilla/feeds"
 )
 
+func recentChangesFeed() *feeds.Feed {
+	feed := &feeds.Feed{
+		Title:       "Recent changes",
+		Link:        &feeds.Link{Href: util.URL},
+		Description: "List of 30 recent changes on the wiki",
+		Author:      &feeds.Author{Name: "Wikimind", Email: "wikimind@mycorrhiza"},
+		Updated:     time.Now(),
+	}
+	var (
+		out, err = gitsh(
+			"log", "--oneline", "--no-merges",
+			"--pretty=format:\"%h\t%ae\t%at\t%s\"",
+			"--max-count=30",
+		)
+		revs []Revision
+	)
+	if err == nil {
+		for _, line := range strings.Split(out.String(), "\n") {
+			revs = append(revs, parseRevisionLine(line))
+		}
+	}
+	for _, rev := range revs {
+		feed.Add(&feeds.Item{
+			Title:       rev.Message,
+			Author:      &feeds.Author{Name: rev.Username},
+			Id:          rev.Hash,
+			Description: rev.descriptionForFeed(),
+			Created:     rev.Time,
+			Updated:     rev.Time,
+			Link:        &feeds.Link{Href: util.URL + rev.bestLink()},
+		})
+	}
+	return feed
+}
+
+func RecentChangesRSS() (string, error) {
+	return recentChangesFeed().ToRss()
+}
+
+func RecentChangesAtom() (string, error) {
+	return recentChangesFeed().ToAtom()
+}
+
+func RecentChangesJSON() (string, error) {
+	return recentChangesFeed().ToJSON()
+}
+
 func RecentChanges(n int) string {
 	var (
 		out, err = gitsh(

http_history.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"log"
 	"net/http"
 	"strconv"
@@ -14,6 +15,9 @@ import (
 func init() {
 	http.HandleFunc("/history/", handlerHistory)
 	http.HandleFunc("/recent-changes/", handlerRecentChanges)
+	http.HandleFunc("/recent-changes-rss", handlerRecentChangesRSS)
+	http.HandleFunc("/recent-changes-atom", handlerRecentChangesAtom)
+	http.HandleFunc("/recent-changes-json", handlerRecentChangesJSON)
 }
 
 // handlerHistory lists all revisions of a hypha
@@ -46,3 +50,28 @@ func handlerRecentChanges(w http.ResponseWriter, rq *http.Request) {
 		http.Redirect(w, rq, "/recent-changes/20", http.StatusSeeOther)
 	}
 }
+
+func genericHandlerOfFeeds(w http.ResponseWriter, rq *http.Request, f func() (string, error), name string) {
+	log.Println(rq.URL)
+	if content, err := f(); err != nil {
+		w.Header().Set("Content-Type", "text/plain;charset=utf-8")
+		w.WriteHeader(http.StatusInternalServerError)
+		fmt.Fprint(w, "An error while generating "+name+": "+err.Error())
+	} else {
+		w.Header().Set("Content-Type", "application/rss+xml")
+		w.WriteHeader(http.StatusOK)
+		fmt.Fprint(w, content)
+	}
+}
+
+func handlerRecentChangesRSS(w http.ResponseWriter, rq *http.Request) {
+	genericHandlerOfFeeds(w, rq, history.RecentChangesRSS, "RSS")
+}
+
+func handlerRecentChangesAtom(w http.ResponseWriter, rq *http.Request) {
+	genericHandlerOfFeeds(w, rq, history.RecentChangesAtom, "Atom")
+}
+
+func handlerRecentChangesJSON(w http.ResponseWriter, rq *http.Request) {
+	genericHandlerOfFeeds(w, rq, history.RecentChangesJSON, "JSON feed")
+}

templates/asset.qtpl.go

@@ -39,6 +39,7 @@ textarea {font-size:15px;}
 .edit {height:100%;}
 .edit-form {height:90%;}
 .edit-form textarea {width:100%;height:90%;}
+.icon {margin-right: .25rem; vertical-align: bottom; }
 
 main h1:not(.navi-title) {font-size:1.7rem;}
 blockquote {border-left: 4px black solid; margin-left: 0; padding-left: 1rem;}

templates/default.css

@@ -14,6 +14,7 @@ textarea {font-size:15px;}
 .edit {height:100%;}
 .edit-form {height:90%;}
 .edit-form textarea {width:100%;height:90%;}
+.icon {margin-right: .25rem; vertical-align: bottom; }
 
 main h1:not(.navi-title) {font-size:1.7rem;}
 blockquote {border-left: 4px black solid; margin-left: 0; padding-left: 1rem;}

templates/recent_changes.qtpl

@@ -18,6 +18,8 @@
 		recent changes
 	</nav>
 
+	<p><img class="icon" width="20" height="20" src="https://upload.wikimedia.org/wikipedia/commons/4/46/Generic_Feed-icon.svg">Subscribe via <a href="/recent-changes-rss">RSS</a>, <a href="/recent-changes-atom">Atom</a> or <a href="/recent-changes-json">JSON feed</a>.</p>
+
 	{% comment %}
 		Here I am, willing to add some accesibility using ARIA. Turns out,
 		role="feed" is not supported in any screen reader as of September

templates/recent_changes.qtpl.go

@@ -77,81 +77,83 @@ func StreamRecentChangesHTML(qw422016 *qt422016.Writer, changes []string, n int)
 		recent changes
 	</nav>
 
+	<p><img class="icon" width="20" height="20" src="https://upload.wikimedia.org/wikipedia/commons/4/46/Generic_Feed-icon.svg">Subscribe via <a href="/recent-changes-rss">RSS</a>, <a href="/recent-changes-atom">Atom</a> or <a href="/recent-changes-json">JSON feed</a>.</p>
+
 	`)
-//line templates/recent_changes.qtpl:26
+//line templates/recent_changes.qtpl:28
 	qw422016.N().S(`
 
 	<section class="recent-changes__list" role="feed">
 	`)
-//line templates/recent_changes.qtpl:29
+//line templates/recent_changes.qtpl:31
 	if len(changes) == 0 {
-//line templates/recent_changes.qtpl:29
+//line templates/recent_changes.qtpl:31
 		qw422016.N().S(`
 		<p>Could not find any recent changes.</p>
 	`)
-//line templates/recent_changes.qtpl:31
+//line templates/recent_changes.qtpl:33
 	} else {
-//line templates/recent_changes.qtpl:31
+//line templates/recent_changes.qtpl:33
 		qw422016.N().S(`
 		`)
-//line templates/recent_changes.qtpl:32
+//line templates/recent_changes.qtpl:34
 		for i, entry := range changes {
-//line templates/recent_changes.qtpl:32
+//line templates/recent_changes.qtpl:34
 			qw422016.N().S(`
 		<ul class="recent-changes__entry rc-entry" role="article"
 		    aria-setsize="`)
-//line templates/recent_changes.qtpl:34
+//line templates/recent_changes.qtpl:36
 			qw422016.N().D(n)
-//line templates/recent_changes.qtpl:34
+//line templates/recent_changes.qtpl:36
 			qw422016.N().S(`" aria-posinset="`)
-//line templates/recent_changes.qtpl:34
+//line templates/recent_changes.qtpl:36
 			qw422016.N().D(i)
-//line templates/recent_changes.qtpl:34
+//line templates/recent_changes.qtpl:36
 			qw422016.N().S(`">
 			 `)
-//line templates/recent_changes.qtpl:35
+//line templates/recent_changes.qtpl:37
 			qw422016.N().S(entry)
-//line templates/recent_changes.qtpl:35
+//line templates/recent_changes.qtpl:37
 			qw422016.N().S(`
 		</ul>
 		`)
-//line templates/recent_changes.qtpl:37
+//line templates/recent_changes.qtpl:39
 		}
-//line templates/recent_changes.qtpl:37
+//line templates/recent_changes.qtpl:39
 		qw422016.N().S(`
 	`)
-//line templates/recent_changes.qtpl:38
+//line templates/recent_changes.qtpl:40
 	}
-//line templates/recent_changes.qtpl:38
+//line templates/recent_changes.qtpl:40
 	qw422016.N().S(`
 	</section>
 </main>
 `)
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 }
 
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 func WriteRecentChangesHTML(qq422016 qtio422016.Writer, changes []string, n int) {
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 	qw422016 := qt422016.AcquireWriter(qq422016)
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 	StreamRecentChangesHTML(qw422016, changes, n)
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 	qt422016.ReleaseWriter(qw422016)
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 }
 
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 func RecentChangesHTML(changes []string, n int) string {
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 	qb422016 := qt422016.AcquireByteBuffer()
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 	WriteRecentChangesHTML(qb422016, changes, n)
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 	qs422016 := string(qb422016.B)
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 	qt422016.ReleaseByteBuffer(qb422016)
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 	return qs422016
-//line templates/recent_changes.qtpl:41
+//line templates/recent_changes.qtpl:43
 }

util/util.go

@@ -8,6 +8,7 @@ import (
 )
 
 var (
+	URL                  string
 	ServerPort           string
 	HomePage             string
 	SiteTitle            string