RSS/Atom support for Repos (#19055)

* support for repos
* refactor
* advertise the feeds via meta tags
* allow feed suffix and feed header
* optimize performance

6 files changed, 85 insertions, 64 deletions

diff --git a/routers/web/feed/convert.go b/routers/web/feed/convert.go
index 51df014f1d..64801a6078 100644
--- a/routers/web/feed/convert.go
+++ b/routers/web/feed/convert.go
@@ -7,6 +7,7 @@ package feed
 import (
 	"fmt"
 	"html"
+	"net/http"
 	"net/url"
 	"strconv"
 	"strings"
@@ -66,7 +67,7 @@ func renderMarkdown(ctx *context.Context, act *models.Action, content string) st
 }
 
 // feedActionsToFeedItems convert gitea's Action feed to feeds Item
-func feedActionsToFeedItems(ctx *context.Context, actions []*models.Action) (items []*feeds.Item, err error) {
+func feedActionsToFeedItems(ctx *context.Context, actions models.ActionList) (items []*feeds.Item, err error) {
 	for _, act := range actions {
 		act.LoadActUser()
 
@@ -247,3 +248,18 @@ func feedActionsToFeedItems(ctx *context.Context, actions []*models.Action) (ite
 	}
 	return
 }
+
+// GetFeedType return if it is a feed request and altered name and feed type.
+func GetFeedType(name string, req *http.Request) (bool, string, string) {
+	if strings.HasSuffix(name, ".rss") ||
+		strings.Contains(req.Header.Get("Accept"), "application/rss+xml") {
+		return true, strings.TrimSuffix(name, ".rss"), "rss"
+	}
+
+	if strings.HasSuffix(name, ".atom") ||
+		strings.Contains(req.Header.Get("Accept"), "application/atom+xml") {
+		return true, strings.TrimSuffix(name, ".atom"), "atom"
+	}
+
+	return false, name, ""
+}
diff --git a/routers/web/feed/profile.go b/routers/web/feed/profile.go
index 4c1eff04a9..a7b8efcdbe 100644
--- a/routers/web/feed/profile.go
+++ b/routers/web/feed/profile.go
@@ -15,48 +15,9 @@ import (
 	"github.com/gorilla/feeds"
 )
 
-// RetrieveFeeds loads feeds for the specified user
-func RetrieveFeeds(ctx *context.Context, options models.GetFeedsOptions) []*models.Action {
-	actions, err := models.GetFeeds(options)
-	if err != nil {
-		ctx.ServerError("GetFeeds", err)
-		return nil
-	}
-
-	// TODO: move load repoOwner of act.Repo into models.GetFeeds->loadAttributes()
-	{
-		userCache := map[int64]*user_model.User{options.RequestedUser.ID: options.RequestedUser}
-		if ctx.User != nil {
-			userCache[ctx.User.ID] = ctx.User
-		}
-		for _, act := range actions {
-			if act.ActUser != nil {
-				userCache[act.ActUserID] = act.ActUser
-			}
-		}
-		for _, act := range actions {
-			repoOwner, ok := userCache[act.Repo.OwnerID]
-			if !ok {
-				repoOwner, err = user_model.GetUserByID(act.Repo.OwnerID)
-				if err != nil {
-					if user_model.IsErrUserNotExist(err) {
-						continue
-					}
-					ctx.ServerError("GetUserByID", err)
-					return nil
-				}
-				userCache[repoOwner.ID] = repoOwner
-			}
-			act.Repo.Owner = repoOwner
-		}
-	}
-
-	return actions
-}
-
 // ShowUserFeed show user activity as RSS / Atom feed
 func ShowUserFeed(ctx *context.Context, ctxUser *user_model.User, formatType string) {
-	actions := RetrieveFeeds(ctx, models.GetFeedsOptions{
+	actions, err := models.GetFeeds(ctx, models.GetFeedsOptions{
 		RequestedUser:   ctxUser,
 		Actor:           ctx.User,
 		IncludePrivate:  false,
@@ -64,7 +25,8 @@ func ShowUserFeed(ctx *context.Context, ctxUser *user_model.User, formatType str
 		IncludeDeleted:  false,
 		Date:            ctx.FormString("date"),
 	})
-	if ctx.Written() {
+	if err != nil {
+		ctx.ServerError("GetFeeds", err)
 		return
 	}
 
@@ -75,7 +37,6 @@ func ShowUserFeed(ctx *context.Context, ctxUser *user_model.User, formatType str
 		Created:     time.Now(),
 	}
 
-	var err error
 	feed.Items, err = feedActionsToFeedItems(ctx, actions)
 	if err != nil {
 		ctx.ServerError("convert feed", err)
diff --git a/routers/web/feed/repo.go b/routers/web/feed/repo.go
new file mode 100644
index 0000000000..53fb8148e0
--- /dev/null
+++ b/routers/web/feed/repo.go
@@ -0,0 +1,44 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package feed
+
+import (
+	"time"
+
+	"code.gitea.io/gitea/models"
+	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/modules/context"
+
+	"github.com/gorilla/feeds"
+)
+
+// ShowRepoFeed shows user activity on the repo as RSS / Atom feed
+func ShowRepoFeed(ctx *context.Context, repo *repo_model.Repository, formatType string) {
+	actions, err := models.GetFeeds(ctx, models.GetFeedsOptions{
+		RequestedRepo:  repo,
+		Actor:          ctx.User,
+		IncludePrivate: true,
+		Date:           ctx.FormString("date"),
+	})
+	if err != nil {
+		ctx.ServerError("GetFeeds", err)
+		return
+	}
+
+	feed := &feeds.Feed{
+		Title:       ctx.Tr("home.feed_of", repo.FullName()),
+		Link:        &feeds.Link{Href: repo.HTMLURL()},
+		Description: repo.Description,
+		Created:     time.Now(),
+	}
+
+	feed.Items, err = feedActionsToFeedItems(ctx, actions)
+	if err != nil {
+		ctx.ServerError("convert feed", err)
+		return
+	}
+
+	writeFeed(ctx, feed, formatType)
+}
diff --git a/routers/web/repo/view.go b/routers/web/repo/view.go
index 9ff72b2102..5293d3c6a3 100644
--- a/routers/web/repo/view.go
+++ b/routers/web/repo/view.go
@@ -38,6 +38,7 @@ import (
 	"code.gitea.io/gitea/modules/structs"
 	"code.gitea.io/gitea/modules/typesniffer"
 	"code.gitea.io/gitea/modules/util"
+	"code.gitea.io/gitea/routers/web/feed"
 )
 
 const (
@@ -691,6 +692,14 @@ func checkHomeCodeViewable(ctx *context.Context) {
 
 // Home render repository home page
 func Home(ctx *context.Context) {
+	isFeed, _, showFeedType := feed.GetFeedType(ctx.Params(":reponame"), ctx.Req)
+	if isFeed {
+		feed.ShowRepoFeed(ctx, ctx.Repo.Repository, showFeedType)
+		return
+	}
+
+	ctx.Data["FeedURL"] = ctx.Repo.Repository.HTMLURL()
+
 	checkHomeCodeViewable(ctx)
 	if ctx.Written() {
 		return
diff --git a/routers/web/user/home.go b/routers/web/user/home.go
index 379e1f8e20..877aa45280 100644
--- a/routers/web/user/home.go
+++ b/routers/web/user/home.go
@@ -29,7 +29,6 @@ import (
 	"code.gitea.io/gitea/modules/markup/markdown"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/util"
-	"code.gitea.io/gitea/routers/web/feed"
 	issue_service "code.gitea.io/gitea/services/issue"
 	pull_service "code.gitea.io/gitea/services/pull"
 
@@ -131,7 +130,7 @@ func Dashboard(ctx *context.Context) {
 	ctx.Data["MirrorCount"] = len(mirrors)
 	ctx.Data["Mirrors"] = mirrors
 
-	ctx.Data["Feeds"] = feed.RetrieveFeeds(ctx, models.GetFeedsOptions{
+	ctx.Data["Feeds"], err = models.GetFeeds(ctx, models.GetFeedsOptions{
 		RequestedUser:   ctxUser,
 		RequestedTeam:   ctx.Org.Team,
 		Actor:           ctx.User,
@@ -140,8 +139,8 @@ func Dashboard(ctx *context.Context) {
 		IncludeDeleted:  false,
 		Date:            ctx.FormString("date"),
 	})
-
-	if ctx.Written() {
+	if err != nil {
+		ctx.ServerError("GetFeeds", err)
 		return
 	}
 
diff --git a/routers/web/user/profile.go b/routers/web/user/profile.go
index b4198ef8fd..b84cee2b3a 100644
--- a/routers/web/user/profile.go
+++ b/routers/web/user/profile.go
@@ -74,19 +74,7 @@ func Profile(ctx *context.Context) {
 		uname = strings.TrimSuffix(uname, ".gpg")
 	}
 
-	showFeedType := ""
-	if strings.HasSuffix(uname, ".rss") {
-		showFeedType = "rss"
-		uname = strings.TrimSuffix(uname, ".rss")
-	} else if strings.Contains(ctx.Req.Header.Get("Accept"), "application/rss+xml") {
-		showFeedType = "rss"
-	}
-	if strings.HasSuffix(uname, ".atom") {
-		showFeedType = "atom"
-		uname = strings.TrimSuffix(uname, ".atom")
-	} else if strings.Contains(ctx.Req.Header.Get("Accept"), "application/atom+xml") {
-		showFeedType = "atom"
-	}
+	isShowFeed, uname, showFeedType := feed.GetFeedType(uname, ctx.Req)
 
 	ctxUser := GetUserByName(ctx, uname)
 	if ctx.Written() {
@@ -95,7 +83,7 @@ func Profile(ctx *context.Context) {
 
 	if ctxUser.IsOrganization() {
 		// Show Org RSS feed
-		if len(showFeedType) != 0 {
+		if isShowFeed {
 			feed.ShowUserFeed(ctx, ctxUser, showFeedType)
 			return
 		}
@@ -123,11 +111,14 @@ func Profile(ctx *context.Context) {
 	}
 
 	// Show User RSS feed
-	if len(showFeedType) != 0 {
+	if isShowFeed {
 		feed.ShowUserFeed(ctx, ctxUser, showFeedType)
 		return
 	}
 
+	// advertise feed via meta tag
+	ctx.Data["FeedURL"] = ctxUser.HTMLURL()
+
 	// Show OpenID URIs
 	openIDs, err := user_model.GetUserOpenIDs(ctxUser.ID)
 	if err != nil {
@@ -259,7 +250,7 @@ func Profile(ctx *context.Context) {
 
 		total = ctxUser.NumFollowing
 	case "activity":
-		ctx.Data["Feeds"] = feed.RetrieveFeeds(ctx, models.GetFeedsOptions{
+		ctx.Data["Feeds"], err = models.GetFeeds(ctx, models.GetFeedsOptions{
 			RequestedUser:   ctxUser,
 			Actor:           ctx.User,
 			IncludePrivate:  showPrivate,
@@ -267,7 +258,8 @@ func Profile(ctx *context.Context) {
 			IncludeDeleted:  false,
 			Date:            ctx.FormString("date"),
 		})
-		if ctx.Written() {
+		if err != nil {
+			ctx.ServerError("GetFeeds", err)
 			return
 		}
 	case "stars":