appview: generate atom feed from profile timeline for users

Signed-off-by: dusk <[e-mail]>

Change-Id: uxnwsxtukznolvmwopkpxmtsvztvsusu

appview/middleware/middleware.go

···
 			id, err := mw.idResolver.ResolveIdent(req.Context(), didOrHandle)
 			if err != nil {
 				// invalid did or handle
-				log.Println("failed to resolve did/handle:", err)
+				log.Printf("failed to resolve did/handle '%s': %s\n", didOrHandle, err)
 				mw.pages.Error404(w)
 				return
 			}

appview/state/profile.go

···
 package state
 
 import (
+	"context"
 	"fmt"
 	"log"
 	"net/http"
···
 	"github.com/bluesky-social/indigo/atproto/syntax"
 	lexutil "github.com/bluesky-social/indigo/lex/util"
 	"github.com/go-chi/chi/v5"
+	"github.com/gorilla/feeds"
 	"tangled.sh/tangled.sh/core/api/tangled"
 	"tangled.sh/tangled.sh/core/appview/db"
 	"tangled.sh/tangled.sh/core/appview/pages"
···
 			Following:    following,
 		},
 	})
+}
+
+func (s *State) feedFromRequest(w http.ResponseWriter, r *http.Request) *feeds.Feed {
+	ident, ok := r.Context().Value("resolvedId").(identity.Identity)
+	if !ok {
+		s.pages.Error404(w)
+		return nil
+	}
+
+	feed, err := s.GetProfileFeed(r.Context(), ident.Handle.String(), ident.DID.String())
+	if err != nil {
+		s.pages.Error500(w)
+		return nil
+	}
+
+	return feed
+}
+
+func (s *State) AtomFeedPage(w http.ResponseWriter, r *http.Request) {
+	feed := s.feedFromRequest(w, r)
+	if feed == nil {
+		return
+	}
+
+	atom, err := feed.ToAtom()
+	if err != nil {
+		s.pages.Error500(w)
+		return
+	}
+
+	w.Header().Set("content-type", "application/atom+xml")
+	w.Write([]byte(atom))
+}
+
+func (s *State) GetProfileFeed(ctx context.Context, handle string, did string) (*feeds.Feed, error) {
+	timeline, err := db.MakeProfileTimeline(s.db, did)
+	if err != nil {
+		return nil, err
+	}
+
+	author := &feeds.Author{
+		Name: fmt.Sprintf("@%s", handle),
+	}
+	feed := &feeds.Feed{
+		Title:   fmt.Sprintf("timeline feed for %s", author.Name),
+		Link:    &feeds.Link{Href: fmt.Sprintf("%s/@%s", s.config.Core.AppviewHost, handle), Type: "text/html", Rel: "alternate"},
+		Items:   make([]*feeds.Item, 0),
+		Updated: time.UnixMilli(0),
+		Author:  author,
+	}
+	for _, byMonth := range timeline.ByMonth {
+		for _, pull := range byMonth.PullEvents.Items {
+			owner, err := s.idResolver.ResolveIdent(ctx, pull.Repo.Did)
+			if err != nil {
+				return nil, err
+			}
+			feed.Items = append(feed.Items, &feeds.Item{
+				Title:   fmt.Sprintf("%s created pull request '%s' in @%s/%s", author.Name, pull.Title, owner.Handle, pull.Repo.Name),
+				Link:    &feeds.Link{Href: fmt.Sprintf("%s/@%s/%s/pulls/%d", s.config.Core.AppviewHost, owner.Handle, pull.Repo.Name, pull.PullId), Type: "text/html", Rel: "alternate"},
+				Created: pull.Created,
+				Author:  author,
+			})
+			for _, submission := range pull.Submissions {
+				feed.Items = append(feed.Items, &feeds.Item{
+					Title:   fmt.Sprintf("%s submitted pull request '%s' (round #%d) in @%s/%s", author.Name, pull.Title, submission.RoundNumber, owner.Handle, pull.Repo.Name),
+					Link:    &feeds.Link{Href: fmt.Sprintf("%s/@%s/%s/pulls/%d", s.config.Core.AppviewHost, owner.Handle, pull.Repo.Name, pull.PullId), Type: "text/html", Rel: "alternate"},
+					Created: submission.Created,
+					Author:  author,
+				})
+			}
+		}
+		for _, issue := range byMonth.IssueEvents.Items {
+			owner, err := s.idResolver.ResolveIdent(ctx, issue.Metadata.Repo.Did)
+			if err != nil {
+				return nil, err
+			}
+			feed.Items = append(feed.Items, &feeds.Item{
+				Title:   fmt.Sprintf("%s created issue '%s' in @%s/%s", author.Name, issue.Title, owner.Handle, issue.Metadata.Repo.Name),
+				Link:    &feeds.Link{Href: fmt.Sprintf("%s/@%s/%s/issues/%d", s.config.Core.AppviewHost, owner.Handle, issue.Metadata.Repo.Name, issue.IssueId), Type: "text/html", Rel: "alternate"},
+				Created: issue.Created,
+				Author:  author,
+			})
+		}
+		for _, repo := range byMonth.RepoEvents {
+			var title string
+			if repo.Source != nil {
+				id, err := s.idResolver.ResolveIdent(ctx, repo.Source.Did)
+				if err != nil {
+					return nil, err
+				}
+				title = fmt.Sprintf("%s forked repository @%s/%s to '%s'", author.Name, id.Handle, repo.Source.Name, repo.Repo.Name)
+			} else {
+				title = fmt.Sprintf("%s created repository '%s'", author.Name, repo.Repo.Name)
+			}
+			feed.Items = append(feed.Items, &feeds.Item{
+				Title:   title,
+				Link:    &feeds.Link{Href: fmt.Sprintf("%s/@%s/%s", s.config.Core.AppviewHost, handle, repo.Repo.Name), Type: "text/html", Rel: "alternate"},
+				Created: repo.Repo.Created,
+				Author:  author,
+			})
+		}
+	}
+	slices.SortFunc(feed.Items, func(a *feeds.Item, b *feeds.Item) int {
+		return int(b.Created.UnixMilli()) - int(a.Created.UnixMilli())
+	})
+	if len(feed.Items) > 0 {
+		feed.Updated = feed.Items[0].Created
+	}
+
+	return feed, nil
 }
 
 func (s *State) UpdateProfileBio(w http.ResponseWriter, r *http.Request) {

appview/state/router.go

···
 
 	r.With(mw.ResolveIdent()).Route("/{user}", func(r chi.Router) {
 		r.Get("/", s.Profile)
+		r.Get("/feed.atom", s.AtomFeedPage)
 
 		r.With(mw.ResolveRepo()).Route("/{repo}", func(r chi.Router) {
 			r.Use(mw.GoImport())

go.mod

···
 	github.com/golang/mock v1.6.0 // indirect
 	github.com/google/go-querystring v1.1.0 // indirect
 	github.com/gorilla/css v1.0.1 // indirect
+	github.com/gorilla/feeds v1.2.0 // indirect
 	github.com/gorilla/securecookie v1.1.2 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
 	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect

go.sum

···
 github.com/gopherjs/gopherjs v0.0.0-20190430165422-3e4dfb77656c/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/gorilla/css v1.0.1 h1:ntNaBIghp6JmvWnxbZKANoLyuXTPZ4cAMlo6RyhlbO8=
 github.com/gorilla/css v1.0.1/go.mod h1:BvnYkspnSzMmwRK+b8/xgNPLiIuNZr6vbZBTPQ2A3b0=
+github.com/gorilla/feeds v1.2.0 h1:O6pBiXJ5JHhPvqy53NsjKOThq+dNFm8+DFrxBEdzSCc=
+github.com/gorilla/feeds v1.2.0/go.mod h1:WMib8uJP3BbY+X8Szd1rA5Pzhdfh+HCCAYT2z7Fza6Y=
 github.com/gorilla/securecookie v1.1.2 h1:YCIWL56dvtr73r6715mJs5ZvhtnY73hBvEF8kXD8ePA=
 github.com/gorilla/securecookie v1.1.2/go.mod h1:NfCASbcHqRSY+3a8tlWJwsQap2VX5pwzwo4h3eOamfo=
 github.com/gorilla/sessions v1.4.0 h1:kpIYOp/oi6MG/p5PgxApU8srsSw9tuFbt46Lt7auzqQ=