Use User.ID instead of User.Name in ActivityPub API for Person IRI (#23823)

Thanks to @trwnh

Close #23802

The ActivityPub id is an HTTPS URI that should remain constant, even if
the user changes their name.

3 files changed, 18 insertions, 11 deletions

diff --git a/routers/api/v1/activitypub/person.go b/routers/api/v1/activitypub/person.go
index 492930b849..bc6b82b179 100644
--- a/routers/api/v1/activitypub/person.go
+++ b/routers/api/v1/activitypub/person.go
@@ -4,6 +4,7 @@
 package activitypub
 
 import (
+	"fmt"
 	"net/http"
 	"strings"
 
@@ -18,22 +19,23 @@ import (
 
 // Person function returns the Person actor for a user
 func Person(ctx *context.APIContext) {
-	// swagger:operation GET /activitypub/user/{username} activitypub activitypubPerson
+	// swagger:operation GET /activitypub/user-id/{user-id} activitypub activitypubPerson
 	// ---
 	// summary: Returns the Person actor for a user
 	// produces:
 	// - application/json
 	// parameters:
-	// - name: username
+	// - name: user-id
 	//   in: path
-	//   description: username of the user
-	//   type: string
+	//   description: user ID of the user
+	//   type: integer
 	//   required: true
 	// responses:
 	//   "200":
 	//     "$ref": "#/responses/ActivityPub"
 
-	link := strings.TrimSuffix(setting.AppURL, "/") + "/api/v1/activitypub/user/" + ctx.ContextUser.Name
+	// TODO: the setting.AppURL during the test doesn't follow the definition: "It always has a '/' suffix"
+	link := fmt.Sprintf("%s/api/v1/activitypub/user-id/%d", strings.TrimSuffix(setting.AppURL, "/"), ctx.ContextUser.ID)
 	person := ap.PersonNew(ap.IRI(link))
 
 	person.Name = ap.NaturalLanguageValuesNew()
@@ -85,16 +87,16 @@ func Person(ctx *context.APIContext) {
 
 // PersonInbox function handles the incoming data for a user inbox
 func PersonInbox(ctx *context.APIContext) {
-	// swagger:operation POST /activitypub/user/{username}/inbox activitypub activitypubPersonInbox
+	// swagger:operation POST /activitypub/user-id/{user-id}/inbox activitypub activitypubPersonInbox
 	// ---
 	// summary: Send to the inbox
 	// produces:
 	// - application/json
 	// parameters:
-	// - name: username
+	// - name: user-id
 	//   in: path
-	//   description: username of the user
-	//   type: string
+	//   description: user ID of the user
+	//   type: integer
 	//   required: true
 	// responses:
 	//   "204":
diff --git a/routers/api/v1/api.go b/routers/api/v1/api.go
index 8b13f5492c..21797bd1a0 100644
--- a/routers/api/v1/api.go
+++ b/routers/api/v1/api.go
@@ -704,10 +704,15 @@ func Routes(ctx gocontext.Context) *web.Route {
 		if setting.Federation.Enabled {
 			m.Get("/nodeinfo", misc.NodeInfo)
 			m.Group("/activitypub", func() {
+				// deprecated, remove in 1.20, use /user-id/{user-id} instead
 				m.Group("/user/{username}", func() {
 					m.Get("", activitypub.Person)
 					m.Post("/inbox", activitypub.ReqHTTPSignature(), activitypub.PersonInbox)
 				}, context_service.UserAssignmentAPI())
+				m.Group("/user-id/{user-id}", func() {
+					m.Get("", activitypub.Person)
+					m.Post("/inbox", activitypub.ReqHTTPSignature(), activitypub.PersonInbox)
+				}, context_service.UserIDAssignmentAPI())
 			})
 		}
 		m.Get("/signing-key.gpg", misc.SigningKey)
diff --git a/routers/web/webfinger.go b/routers/web/webfinger.go
index a8e816d7b7..1442e09a31 100644
--- a/routers/web/webfinger.go
+++ b/routers/web/webfinger.go
@@ -85,7 +85,7 @@ func WebfingerQuery(ctx *context.Context) {
 
 	aliases := []string{
 		u.HTMLURL(),
-		appURL.String() + "api/v1/activitypub/user/" + url.PathEscape(u.Name),
+		appURL.String() + "api/v1/activitypub/user-id/" + fmt.Sprint(u.ID),
 	}
 	if !u.KeepEmailPrivate {
 		aliases = append(aliases, fmt.Sprintf("mailto:%s", u.Email))
@@ -104,7 +104,7 @@ func WebfingerQuery(ctx *context.Context) {
 		{
 			Rel:  "self",
 			Type: "application/activity+json",
-			Href: appURL.String() + "api/v1/activitypub/user/" + url.PathEscape(u.Name),
+			Href: appURL.String() + "api/v1/activitypub/user-id/" + fmt.Sprint(u.ID),
 		},
 	}