From b922b8382084eeff3ee95a349eeb9cd0a610745c Mon Sep 17 00:00:00 2001
From: bnewbold <bnewbold@robocracy.org>
Date: Sat, 23 Dec 2023 21:38:21 +0100
Subject: [PATCH] yet more RSS tweaks (#2289)

* rss: full URL in RSS link; use request Host in URLs

Full URL syntax on request from third parties.

Using the actual request host should fix issues with non-bsky-production
deployments. It is HTTPS-only, so doesn't work perfectly for local dev.

* rss: make /profile/{handle}/rss an HTTP redirect

Motivation is easier discoverability of RSS feed.
---
 bskyweb/cmd/bskyweb/rss.go     | 33 ++++++++++++++++++++++++++++-----
 bskyweb/cmd/bskyweb/server.go  |  3 ++-
 bskyweb/templates/profile.html |  4 +++-
 3 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/bskyweb/cmd/bskyweb/rss.go b/bskyweb/cmd/bskyweb/rss.go
index 4cdc78f8..64e67fd2 100644
--- a/bskyweb/cmd/bskyweb/rss.go
+++ b/bskyweb/cmd/bskyweb/rss.go
@@ -4,6 +4,7 @@ import (
 	"encoding/xml"
 	"fmt"
 	"net/http"
+	"strings"
 	"time"
 
 	appbsky "github.com/bluesky-social/indigo/api/bsky"
@@ -39,11 +40,33 @@ type rss struct {
 
 func (srv *Server) WebProfileRSS(c echo.Context) error {
 	ctx := c.Request().Context()
+	req := c.Request()
 
-	didParam := c.Param("did")
-	did, err := syntax.ParseDID(didParam)
+	identParam := c.Param("ident")
+
+	// if not a DID, try parsing as a handle and doing a redirect
+	if !strings.HasPrefix(identParam, "did:") {
+		handle, err := syntax.ParseHandle(identParam)
+		if err != nil {
+			return echo.NewHTTPError(400, fmt.Sprintf("not a valid handle: %s", identParam))
+		}
+
+		// check that public view is Ok, and resolve DID
+		pv, err := appbsky.ActorGetProfile(ctx, srv.xrpcc, handle.String())
+		if err != nil {
+			return echo.NewHTTPError(404, fmt.Sprintf("account not found: %s", handle))
+		}
+		for _, label := range pv.Labels {
+			if label.Src == pv.Did && label.Val == "!no-unauthenticated" {
+				return echo.NewHTTPError(403, fmt.Sprintf("account does not allow public views: %s", handle))
+			}
+		}
+		return c.Redirect(http.StatusFound, fmt.Sprintf("/profile/%s/rss", pv.Did))
+	}
+
+	did, err := syntax.ParseDID(identParam)
 	if err != nil {
-		return echo.NewHTTPError(400, fmt.Sprintf("not a valid DID: %s", didParam))
+		return echo.NewHTTPError(400, fmt.Sprintf("not a valid DID: %s", identParam))
 	}
 
 	// check that public view is Ok
@@ -84,7 +107,7 @@ func (srv *Server) WebProfileRSS(c echo.Context) error {
 			pubDate = createdAt.Time().Format(time.RFC822Z)
 		}
 		posts = append(posts, Item{
-			Link:        fmt.Sprintf("https://bsky.app/profile/%s/post/%s", pv.Handle, aturi.RecordKey().String()),
+			Link:        fmt.Sprintf("https://%s/profile/%s/post/%s", req.Host, pv.Handle, aturi.RecordKey().String()),
 			Description: rec.Text,
 			PubDate:     pubDate,
 			GUID: ItemGUID{
@@ -105,7 +128,7 @@ func (srv *Server) WebProfileRSS(c echo.Context) error {
 	feed := &rss{
 		Version:     "2.0",
 		Description: desc,
-		Link:        fmt.Sprintf("https://bsky.app/profile/%s", pv.Handle),
+		Link:        fmt.Sprintf("https://%s/profile/%s", req.Host, pv.Handle),
 		Title:       title,
 		Item:        posts,
 	}
diff --git a/bskyweb/cmd/bskyweb/server.go b/bskyweb/cmd/bskyweb/server.go
index 5d9a481f..b0fde255 100644
--- a/bskyweb/cmd/bskyweb/server.go
+++ b/bskyweb/cmd/bskyweb/server.go
@@ -210,7 +210,7 @@ func serve(cctx *cli.Context) error {
 	e.GET("/profile/:handle/feed/:rkey/liked-by", server.WebGeneric)
 
 	// profile RSS feed (DID not handle)
-	e.GET("/profile/:did/rss", server.WebProfileRSS)
+	e.GET("/profile/:ident/rss", server.WebProfileRSS)
 
 	// post endpoints; only first populates info
 	e.GET("/profile/:handle/post/:rkey", server.WebPost)
@@ -370,6 +370,7 @@ func (srv *Server) WebProfile(c echo.Context) error {
 	req := c.Request()
 	data["profileView"] = pv
 	data["requestURI"] = fmt.Sprintf("https://%s%s", req.Host, req.URL.Path)
+	data["requestHost"] = req.Host
 	return c.Render(http.StatusOK, "profile.html", data)
 }
 
diff --git a/bskyweb/templates/profile.html b/bskyweb/templates/profile.html
index 71c10032..551dc15a 100644
--- a/bskyweb/templates/profile.html
+++ b/bskyweb/templates/profile.html
@@ -34,7 +34,9 @@
   {% endif %}
   <meta name="twitter:label1" content="Account DID">
   <meta name="twitter:value1" content="{{ profileView.Did }}">
-  <link rel="alternate" type="application/rss+xml" href="/profile/{{ profileView.Did }}/rss">
+  {%- if requestHost %}
+  <link rel="alternate" type="application/rss+xml" href="https://{{ requestHost }}/profile/{{ profileView.Did }}/rss">
+  {% endif %}
 {% endif -%}
 {%- endblock %}