Add native blogroll integration

blogroll.go

@@ -0,0 +1,115 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"time"
+
+	"github.com/kaorimatz/go-opml"
+	"github.com/thoas/go-funk"
+	"golang.org/x/sync/singleflight"
+)
+
+var blogrollCacheGroup singleflight.Group
+
+func serveBlogroll(w http.ResponseWriter, r *http.Request) {
+	blog := r.Context().Value(blogContextKey).(string)
+	c := appConfig.Blogs[blog].Blogroll
+	if !c.Enabled {
+		serve404(w, r)
+		return
+	}
+	outlines, err, _ := blogrollCacheGroup.Do(blog, func() (interface{}, error) {
+		return getBlogrollOutlines(c)
+	})
+	if err != nil {
+		serveError(w, r, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	if appConfig.Cache != nil && appConfig.Cache.Enable {
+		setInternalCacheExpirationHeader(w, r, int(appConfig.Cache.Expiration))
+	}
+	render(w, r, templateBlogroll, &renderData{
+		BlogString: blog,
+		Data: map[string]interface{}{
+			"Title":       c.Title,
+			"Description": c.Description,
+			"Outlines":    outlines,
+			"Download":    c.Path + ".opml",
+		},
+	})
+}
+
+func serveBlogrollExport(w http.ResponseWriter, r *http.Request) {
+	blog := r.Context().Value(blogContextKey).(string)
+	c := appConfig.Blogs[blog].Blogroll
+	if !c.Enabled {
+		serve404(w, r)
+		return
+	}
+	outlines, err, _ := blogrollCacheGroup.Do(blog, func() (interface{}, error) {
+		return getBlogrollOutlines(c)
+	})
+	if err != nil {
+		serveError(w, r, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	if appConfig.Cache != nil && appConfig.Cache.Enable {
+		setInternalCacheExpirationHeader(w, r, int(appConfig.Cache.Expiration))
+	}
+	w.Header().Set(contentType, contentTypeXMLUTF8)
+	mw := minifier.Writer(contentTypeXML, w)
+	defer func() {
+		_ = mw.Close()
+	}()
+	_ = opml.Render(mw, &opml.OPML{
+		Version:     "2.0",
+		DateCreated: time.Now().UTC(),
+		Outlines:    outlines.([]*opml.Outline),
+	})
+}
+
+func getBlogrollOutlines(config *configBlogroll) ([]*opml.Outline, error) {
+	if config.cachedOutlines != nil && time.Since(config.lastCache).Minutes() < 60 {
+		// return cache if younger than 60 min
+		return config.cachedOutlines, nil
+	}
+	req, err := http.NewRequest(http.MethodGet, config.Opml, nil)
+	if err != nil {
+		return nil, err
+	}
+	if config.AuthHeader != "" && config.AuthValue != "" {
+		req.Header.Set(config.AuthHeader, config.AuthValue)
+	}
+	res, err := appHttpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		_, _ = io.Copy(io.Discard, res.Body)
+		res.Body.Close()
+	}()
+	if code := res.StatusCode; code < 200 || 300 <= code {
+		return nil, fmt.Errorf("opml request not successfull, status code: %d", code)
+	}
+	o, err := opml.Parse(res.Body)
+	if err != nil {
+		return nil, err
+	}
+	outlines := o.Outlines
+	if len(config.Categories) > 0 {
+		filtered := []*opml.Outline{}
+		for _, category := range config.Categories {
+			if outline, ok := funk.Find(outlines, func(outline *opml.Outline) bool {
+				return outline.Title == category || outline.Text == category
+			}).(*opml.Outline); ok && outline != nil {
+				filtered = append(filtered, outline)
+			}
+		}
+		outlines = filtered
+	}
+	config.cachedOutlines = outlines
+	config.lastCache = time.Now()
+	return outlines, nil
+}

cache.go

@@ -21,7 +21,7 @@ import (
 )
 
 const (
-	cacheInternalExpirationHeader = "GoBlog-Expire"
+	cacheInternalExpirationHeader = "Goblog-Expire"
 )
 
 var (
@@ -212,6 +212,9 @@ func purgeCache() {
 	cacheR.Clear()
 }
 
-func setInternalCacheExpirationHeader(w http.ResponseWriter, expiration int) {
+func setInternalCacheExpirationHeader(w http.ResponseWriter, r *http.Request, expiration int) {
+	if loggedIn, ok := r.Context().Value(loggedInKey).(bool); ok && loggedIn {
+		return
+	}
 	w.Header().Set(cacheInternalExpirationHeader, strconv.Itoa(expiration))
 }

config.go

@@ -4,7 +4,9 @@ import (
 	"errors"
 	"net/url"
 	"strings"
+	"time"
 
+	"github.com/kaorimatz/go-opml"
 	"github.com/spf13/viper"
 )
 
@@ -63,6 +65,7 @@ type configBlog struct {
 	Photos         *photos             `mapstructure:"photos"`
 	Search         *search             `mapstructure:"search"`
 	BlogStats      *blogStats          `mapstructure:"blogStats"`
+	Blogroll       *configBlogroll     `mapstructure:"blogroll"`
 	CustomPages    []*customPage       `mapstructure:"custompages"`
 	Telegram       *configTelegram     `mapstructure:"telegram"`
 	PostAsHome     bool                `mapstructure:"postAsHome"`
@@ -115,6 +118,19 @@ type blogStats struct {
 	Description string `mapstructure:"description"`
 }
 
+type configBlogroll struct {
+	Enabled        bool     `mapstructure:"enabled"`
+	Path           string   `mapstructure:"path"`
+	Opml           string   `mapstructure:"opml"`
+	AuthHeader     string   `mapstructure:"authHeader"`
+	AuthValue      string   `mapstructure:"authValue"`
+	Categories     []string `mapstructure:"categories"`
+	Title          string   `mapstructure:"title"`
+	Description    string   `mapstructure:"description"`
+	cachedOutlines []*opml.Outline
+	lastCache      time.Time
+}
+
 type customPage struct {
 	Path            string       `mapstructure:"path"`
 	Template        string       `mapstructure:"template"`
@@ -288,6 +304,12 @@ func initConfig() error {
 			b.Comments = &comments{Enabled: false}
 		}
 	}
+	// Check config for each blog
+	for _, blog := range appConfig.Blogs {
+		if br := blog.Blogroll; br != nil && br.Enabled && br.Opml == "" {
+			br.Enabled = false
+		}
+	}
 	return nil
 }
 

customPages.go

@@ -8,9 +8,9 @@ func serveCustomPage(w http.ResponseWriter, r *http.Request) {
 	page := r.Context().Value(customPageContextKey).(*customPage)
 	if appConfig.Cache != nil && appConfig.Cache.Enable && page.Cache {
 		if page.CacheExpiration != 0 {
-			setInternalCacheExpirationHeader(w, page.CacheExpiration)
+			setInternalCacheExpirationHeader(w, r, page.CacheExpiration)
 		} else {
-			setInternalCacheExpirationHeader(w, int(appConfig.Cache.Expiration))
+			setInternalCacheExpirationHeader(w, r, int(appConfig.Cache.Expiration))
 		}
 	}
 	render(w, r, page.Template, &renderData{

example-config.yml

@@ -175,6 +175,17 @@ blogs:
       path: /statistics # Path
       title: Statistics # Title
       description: "Here are some statistics with the number of posts per year:" # Description
+    # Blogroll
+    blogroll:
+      enabled: true # Enable
+      path: /blogroll # Path
+      title: Blogroll # Title
+      description: "I follow these blog:" # Description
+      opml: https://example.com/blogroll.opml # Required, URL to the OPML file
+      authHeader: X-Auth # Optional, header to use for OPML authentication
+      authValue: abc # Authentication value for OPML
+      categories: # Optional, allow only these categories
+        - Blogs
     # Custom pages
     custompages:
       - path: /blogroll # Path

go.mod

@@ -25,6 +25,7 @@ require (
 	github.com/gorilla/handlers v1.5.1
 	github.com/jonboulle/clockwork v0.2.2 // indirect
 	github.com/joncrlsn/dque v0.0.0-20200702023911-3e80e3146ce5
+	github.com/kaorimatz/go-opml v0.0.0-20210201121027-bc8e2852d7f9
 	github.com/kr/text v0.2.0 // indirect
 	github.com/kyokomi/emoji/v2 v2.2.8
 	github.com/lestrrat-go/file-rotatelogs v2.4.0+incompatible

go.sum

@@ -178,6 +178,8 @@ github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1
 github.com/jtolds/gls v4.20.0+incompatible h1:xdiiI2gbIgH/gLH7ADydsJ1uDOEzR8yvV7C0MuV77Wo=
 github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
 github.com/julienschmidt/httprouter v1.2.0/go.mod h1:SYymIcj16QtmaHHD7aYtjjsJG7VTCxuUUipMqKk8s4w=
+github.com/kaorimatz/go-opml v0.0.0-20210201121027-bc8e2852d7f9 h1:+9REu9CK9D1AQ6C/PXXwGRcoKdT04cuHR5JgGD4DKqc=
+github.com/kaorimatz/go-opml v0.0.0-20210201121027-bc8e2852d7f9/go.mod h1:OvY5ZBrAC9kOvM2PZs9Lw0BH+5K7tjrT6T7SFhn27OA=
 github.com/kisielk/errcheck v1.1.0/go.mod h1:EZBBE59ingxPouuu3KfxchcWSUPOHkagtvWXihfKN4Q=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/klauspost/cpuid/v2 v2.0.6 h1:dQ5ueTiftKxp0gyjKSx5+8BtPWkyQbd95m8Gys/RarI=
@@ -413,6 +415,7 @@ golang.org/x/net v0.0.0-20200114155413-6afb5195e5aa/go.mod h1:z5CRVTTTmAJ677TzLL
 golang.org/x/net v0.0.0-20200202094626-16171245cfb2/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20200707034311-ab3426394381/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
+golang.org/x/net v0.0.0-20210119194325-5f4716e94777/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/net v0.0.0-20210421230115-4e50805a0758/go.mod h1:72T/g9IO56b78aLF+1Kcs5dz7/ng1VjMUvfKvpfy+jM=
 golang.org/x/net v0.0.0-20210508051633-16afe75a6701 h1:lQVgcB3+FoAXOb20Dp6zTzAIrpj1k/yOOBN7s+Zv1rA=

http.go

@@ -26,6 +26,7 @@ const (
 	charsetUtf8Suffix = "; charset=utf-8"
 
 	contentTypeHTML          = "text/html"
+	contentTypeXML           = "text/xml"
 	contentTypeJSON          = "application/json"
 	contentTypeWWWForm       = "application/x-www-form-urlencoded"
 	contentTypeMultipartForm = "multipart/form-data"
@@ -35,6 +36,7 @@ const (
 	contentTypeJSONFeed      = "application/feed+json"
 
 	contentTypeHTMLUTF8 = contentTypeHTML + charsetUtf8Suffix
+	contentTypeXMLUTF8  = contentTypeXML + charsetUtf8Suffix
 	contentTypeJSONUTF8 = contentTypeJSON + charsetUtf8Suffix
 	contentTypeASUTF8   = contentTypeAS + charsetUtf8Suffix
 
@@ -542,6 +544,17 @@ func buildDynamicRouter() (*chi.Mux, error) {
 			commentsPath := blogPath + "/comment"
 			r.With(sbm, commentsMiddlewares[blog]).Mount(commentsPath, commentsRouter)
 		}
+
+		// Blogroll
+		if brConfig := blogConfig.Blogroll; brConfig != nil && brConfig.Enabled {
+			brPath := blogPath + brConfig.Path
+			r.Group(func(r chi.Router) {
+				r.Use(privateModeHandler...)
+				r.Use(cacheMiddleware, sbm)
+				r.Get(brPath, serveBlogroll)
+				r.Get(brPath+".opml", serveBlogrollExport)
+			})
+		}
 	}
 
 	// Sitemap

minify.go

@@ -17,7 +17,7 @@ func initMinify() {
 	minifier = minify.New()
 	minifier.AddFunc(contentTypeHTML, mHtml.Minify)
 	minifier.AddFunc("text/css", mCss.Minify)
-	minifier.AddFunc("text/xml", mXml.Minify)
+	minifier.AddFunc(contentTypeXML, mXml.Minify)
 	minifier.AddFunc("application/javascript", mJs.Minify)
 	minifier.AddFunc(contentTypeRSS, mXml.Minify)
 	minifier.AddFunc(contentTypeATOM, mXml.Minify)

render.go

@@ -8,6 +8,7 @@ import (
 	"html/template"
 	"log"
 	"net/http"
+	"net/url"
 	"os"
 	"path"
 	"path/filepath"
@@ -39,6 +40,7 @@ const (
 	templateCommentsAdmin      = "commentsadmin"
 	templateNotificationsAdmin = "notificationsadmin"
 	templateWebmentionAdmin    = "webmentionadmin"
+	templateBlogroll           = "blogroll"
 )
 
 var templates map[string]*template.Template = map[string]*template.Template{}
@@ -164,6 +166,9 @@ func initRendering() error {
 			})
 			return mentions
 		},
+		"urlToString": func(u url.URL) string {
+			return u.String()
+		},
 	}
 
 	baseTemplate, err := template.New("base").Funcs(templateFunctions).ParseFiles(path.Join(templatesDir, templateBase+templatesExt))

sitemap.go

@@ -114,6 +114,12 @@ func serveSitemap(w http.ResponseWriter, r *http.Request) {
 				Loc: appConfig.Server.PublicAddress + bc.getRelativePath(bc.BlogStats.Path),
 			})
 		}
+		// Blogroll
+		if bc.Blogroll != nil && bc.Blogroll.Enabled {
+			sm.Add(&sitemap.URL{
+				Loc: appConfig.Server.PublicAddress + bc.getRelativePath(bc.Blogroll.Path),
+			})
+		}
 		// Custom pages
 		for _, cp := range bc.CustomPages {
 			sm.Add(&sitemap.URL{

templates/blogroll.gohtml

@@ -0,0 +1,24 @@
+{{ define "title" }}
+    <title>{{ .Data.Title }} - {{ .Blog.Title }}</title>
+{{ end }}
+
+{{ define "main" }}
+  <main>
+    {{ with .Data.Title }}<h1>{{ . }}</h1>{{ end }}
+    {{ with .Data.Description }}{{ md . }}{{ end }}
+    <p><a href="{{ blogrelative .Blog .Data.Download }}" class="button" download>{{ string .Blog.Lang "download" }}</a></p>
+    {{ $lang := .Blog.Lang }}
+    {{ range .Data.Outlines }}
+        <h2>{{ with .Title }}{{ . }}{{ else }}{{ with .Text }}{{ . }}{{ end }}{{ end }}</h2>
+        <ul>
+            {{ range .Outlines }}
+                <li><a href="{{ urlToString .HTMLURL }}" target="_blank">{{ with .Title }}{{ . }}{{ else }}{{ with .Text }}{{ . }}{{ end }}{{ end }}</a> (<a href="{{ urlToString .XMLURL }}" target="_blank">{{ string $lang "feed" }}</a>)</li>
+            {{ end }}
+        </ul>
+    {{ end }}
+  </main>
+{{ end }}
+
+{{ define "blogroll" }}
+    {{ template "base" . }}
+{{ end }}

templates/custom/blogroll.gohtml

@@ -1,23 +0,0 @@
-{{ define "title" }}
-    <title>{{ .Data.Title }} - {{ .Blog.Title }}</title>
-{{ end }}
-
-{{ define "main" }}
-  <main>
-    <h1>{{ .Data.Title }}</h1>
-    {{ md .Data.Description }}
-    {{ $opmlJson := index ( jsonFile "data/opml.json" ) "outline" }}
-    {{ range $opmlJson }}
-        {{ md (printf "%s %s" "##" ._text) }}
-        <ul>
-            {{ range (index . "outline") }}
-                <li><a href="{{ ._htmlUrl }}" target="_blank">{{ ._title }}</a> (<a href="{{ ._xmlUrl }}" target="_blank">Feed</a>)</li>
-            {{ end }}
-        </ul>
-    {{ end }}
-  </main>
-{{ end }}
-
-{{ define "blogroll" }}
-    {{ template "base" . }}
-{{ end }}

templates/strings/de.yaml

@@ -6,6 +6,7 @@ confirmdelete: "Löschen bestätigen"
 create: "Erstellen"
 delete: "Löschen"
 docomment: "Kommentieren"
+download: "Herunterladen"
 drafts: "Entwürfe"
 editor: "Editor"
 interactions: "Interaktionen & Kommentare"

templates/strings/default.yaml

@@ -11,8 +11,10 @@ confirmdelete: "Confirm deletion"
 create: "Create"
 delete: "Delete"
 docomment: "Comment"
+download: "Download"
 drafts: "Drafts"
 editor: "Editor"
+feed: "Feed"
 indieauth: "IndieAuth"
 interactions: "Interactions & Comments"
 interactionslabel: "Have you published a response to this? Paste the URL here."