From f5a50ce45772ec6f65b99ad7f093252661ff8ed0 Mon Sep 17 00:00:00 2001
From: Anthony Wang <a@exozy.me>
Date: Sun, 27 Nov 2022 19:29:03 +0000
Subject: [PATCH] Add Note object endpoint

---
 modules/forgefed/repository.go     |  1 +
 routers/api/v1/activitypub/note.go | 64 ++++++++++++++++++++++++++++++
 routers/api/v1/activitypub/repo.go |  2 -
 routers/api/v1/api.go              |  1 +
 services/activitypub/objects.go    | 17 ++++++--
 services/comments/comments.go      |  6 ++-
 6 files changed, 85 insertions(+), 6 deletions(-)
 create mode 100644 routers/api/v1/activitypub/note.go

diff --git a/modules/forgefed/repository.go b/modules/forgefed/repository.go
index 662e0eaa3..3d1319d27 100644
--- a/modules/forgefed/repository.go
+++ b/modules/forgefed/repository.go
@@ -29,6 +29,7 @@ type Repository struct {
 // RepositoryNew initializes a Repository type actor
 func RepositoryNew(id ap.ID) *Repository {
 	a := ap.ActorNew(id, RepositoryType)
+	a.Type = RepositoryType
 	o := Repository{Actor: *a}
 	return &o
 }
diff --git a/routers/api/v1/activitypub/note.go b/routers/api/v1/activitypub/note.go
new file mode 100644
index 000000000..0033aa4aa
--- /dev/null
+++ b/routers/api/v1/activitypub/note.go
@@ -0,0 +1,64 @@
+// 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 activitypub
+
+import (
+	"strconv"
+
+	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/services/activitypub"
+)
+
+// Note function returns the Note object for a comment to an issue or PR
+func Note(ctx *context.APIContext) {
+	// swagger:operation GET /activitypub/note/{username}/{reponame}/{id}/{noteid} activitypub activitypubNote
+	// ---
+	// summary: Returns the Note object for a comment to an issue or PR
+	// produces
+	// - application/activity+json
+	// parameters:
+	// - name: username
+	//   in: path
+	//   description: username of the user
+	//   type: string
+	//   required: true
+	// - name: reponame
+	//   in: path
+	//   description: name of the repo
+	//   type: string
+	//   required: true
+	// - name: id
+	//   in: path
+	//   description: ID number of the issue or PR
+	//   type: string
+	//   required: true
+	// - name: noteid
+	//   in: path
+	//   description: ID number of the comment
+	//   type: string
+	//   required: true
+	// responses:
+	//   "200":
+	//     "$ref": "#/responses/ActivityPub"
+
+	index, err := strconv.ParseInt(ctx.Params("noteid"), 10, 64)
+	if err != nil {
+		ctx.ServerError("ParseInt", err)
+		return
+	}
+	// TODO: index can be spoofed!!!
+	comment, err := issues_model.GetCommentByID(ctx, index)
+	if err != nil {
+		ctx.ServerError("GetCommentByID", err)
+		return
+	}
+	note, err := activitypub.Note(comment)
+	if err != nil {
+		ctx.ServerError("Note", err)
+		return
+	}
+	response(ctx, note)
+}
diff --git a/routers/api/v1/activitypub/repo.go b/routers/api/v1/activitypub/repo.go
index cab978dbd..9f7d93f22 100644
--- a/routers/api/v1/activitypub/repo.go
+++ b/routers/api/v1/activitypub/repo.go
@@ -41,7 +41,6 @@ func Repo(ctx *context.APIContext) {
 
 	iri := ctx.Repo.Repository.GetIRI()
 	repo := forgefed.RepositoryNew(ap.IRI(iri))
-	repo.Type = forgefed.RepositoryType
 
 	repo.Name = ap.NaturalLanguageValuesNew()
 	err := repo.Name.Set("en", ap.Content(ctx.Repo.Repository.Name))
@@ -148,7 +147,6 @@ func RepoInbox(ctx *context.APIContext) {
 	case ap.LikeType:
 		err = star(ctx, activity)
 	default:
-		log.Info("Incoming unsupported ActivityStreams type: %s", activity.Type)
 		ctx.PlainText(http.StatusNotImplemented, "ActivityStreams type not supported")
 		return
 	}
diff --git a/routers/api/v1/api.go b/routers/api/v1/api.go
index 06c80f789..6f8ac7c14 100644
--- a/routers/api/v1/api.go
+++ b/routers/api/v1/api.go
@@ -662,6 +662,7 @@ func Routes(ctx gocontext.Context) *web.Route {
 					m.Get("/followers", activitypub.RepoFollowers)
 				}, repoAssignment())
 				m.Get("/ticket/{username}/{reponame}/{id}", repoAssignment(), activitypub.Ticket)
+				m.Get("/note/{username}/{reponame}/{id}/{noteid}", repoAssignment(), activitypub.Note)
 			})
 		}
 		m.Get("/signing-key.gpg", misc.SigningKey)
diff --git a/services/activitypub/objects.go b/services/activitypub/objects.go
index aa6be99f4..ef4e7f3e2 100644
--- a/services/activitypub/objects.go
+++ b/services/activitypub/objects.go
@@ -15,15 +15,26 @@ import (
 )
 
 // Construct a Note object from a comment
-func Note(comment *issues_model.Comment) *ap.Note {
+func Note(comment *issues_model.Comment) (*ap.Note, error) {
+	err := comment.LoadPoster()
+	if err != nil {
+		return nil, err
+	}
+	err = comment.LoadIssue()
+	if err != nil {
+		return nil, err
+	}
 	note := ap.Note{
 		Type:         ap.NoteType,
 		AttributedTo: ap.IRI(comment.Poster.GetIRI()),
 		Context:      ap.IRI(comment.Issue.GetIRI()),
 	}
 	note.Content = ap.NaturalLanguageValuesNew()
-	_ = note.Content.Set("en", ap.Content(comment.Content))
-	return &note
+	err = note.Content.Set("en", ap.Content(comment.Content))
+	if err != nil {
+		return nil, err
+	}
+	return &note, nil
 }
 
 // Construct a Ticket object from an issue
diff --git a/services/comments/comments.go b/services/comments/comments.go
index a28c4c7f5..8f478c018 100644
--- a/services/comments/comments.go
+++ b/services/comments/comments.go
@@ -32,7 +32,11 @@ func CreateIssueComment(doer *user_model.User, repo *repo_model.Repository, issu
 
 	if strings.Contains(repo.OwnerName, "@") {
 		// Federated comment
-		create := activitypub.Create(repo.OriginalURL + "/inbox", activitypub.Note(comment))
+		note, err := activitypub.Note(comment)
+		if err != nil {
+			return nil, err
+		}
+		create := activitypub.Create(repo.OriginalURL + "/inbox", note)
 		err = activitypub.Send(doer, create)
 		if err != nil {
 			return nil, err