From 3402390b6998cbb7e08f24b41aa797faf5ea1f23 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andr=C3=A9=20Duffeck?= <a.duffeck@opencloud.eu>
Date: Mon, 9 Mar 2026 11:22:27 +0100
Subject: [PATCH] Add endpoints for following/unfollowing drive items to the
 graph API

---
 services/graph/pkg/service/v0/follow.go  | 129 +++++++++++++++++++++++
 services/graph/pkg/service/v0/service.go |   2 +
 2 files changed, 131 insertions(+)
 create mode 100644 services/graph/pkg/service/v0/follow.go

diff --git a/services/graph/pkg/service/v0/follow.go b/services/graph/pkg/service/v0/follow.go
new file mode 100644
index 0000000000..3372c56fa2
--- /dev/null
+++ b/services/graph/pkg/service/v0/follow.go
@@ -0,0 +1,129 @@
+package svc
+
+import (
+	"net/http"
+
+	rpc "github.com/cs3org/go-cs3apis/cs3/rpc/v1beta1"
+	provider "github.com/cs3org/go-cs3apis/cs3/storage/provider/v1beta1"
+	"github.com/opencloud-eu/opencloud/services/graph/pkg/errorcode"
+	revactx "github.com/opencloud-eu/reva/v2/pkg/ctx"
+)
+
+// FollowDriveItem marks a drive item as favorite.
+func (g Graph) FollowDriveItem(w http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+
+	itemID, err := parseIDParam(r, "itemID")
+	if err != nil {
+		g.logger.Debug().Err(err).Msg("could not parse itemID")
+		return
+	}
+
+	gatewayClient, err := g.gatewaySelector.Next()
+	if err != nil {
+		g.logger.Error().Err(err).Msg("could not select next gateway client")
+		errorcode.ServiceNotAvailable.Render(w, r, http.StatusServiceUnavailable, "could not select next gateway client")
+		return
+	}
+
+	ref := &provider.Reference{
+		ResourceId: &itemID,
+	}
+
+	u, ok := revactx.ContextGetUser(ctx)
+	if !ok {
+		errorcode.GeneralException.Render(w, r, http.StatusUnauthorized, "User not found in context")
+		return
+	}
+
+	statReq := &provider.StatRequest{
+		Ref: ref,
+	}
+	statRes, err := gatewayClient.Stat(ctx, statReq)
+	if err != nil {
+		g.logger.Error().Err(err).Msg("could not stat resource")
+		errorcode.GeneralException.Render(w, r, http.StatusInternalServerError, "could not stat resource")
+		return
+	}
+	switch statRes.GetStatus().GetCode() {
+	case rpc.Code_CODE_OK:
+		// continue
+	case rpc.Code_CODE_NOT_FOUND:
+		errorcode.InvalidRequest.Render(w, r, http.StatusBadRequest, "resource not found")
+		return
+	default:
+		errorcode.GeneralException.Render(w, r, http.StatusInternalServerError, "could not stat resource")
+		return
+	}
+
+	req := &provider.AddFavoriteRequest{
+		Ref:    ref,
+		UserId: u.Id,
+	}
+
+	res, err := gatewayClient.AddFavorite(ctx, req)
+	if err != nil {
+		g.logger.Error().Err(err).Msg("could not add favorite")
+		errorcode.GeneralException.Render(w, r, http.StatusInternalServerError, "could not add favorite")
+		return
+	}
+
+	if res.Status.Code != rpc.Code_CODE_OK {
+		errorcode.GeneralException.Render(w, r, http.StatusInternalServerError, "could not add favorite")
+		return
+	}
+
+	w.WriteHeader(http.StatusCreated)
+}
+
+// UnfollowDriveItem unmarks a drive item as favorite.
+func (g Graph) UnfollowDriveItem(w http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+	itemID, err := parseIDParam(r, "itemID")
+	if err != nil {
+		g.logger.Debug().Err(err).Msg("could not parse itemID")
+		return
+	}
+
+	gatewayClient, err := g.gatewaySelector.Next()
+	if err != nil {
+		g.logger.Error().Err(err).Msg("could not select next gateway client")
+		errorcode.ServiceNotAvailable.Render(w, r, http.StatusServiceUnavailable, "could not select next gateway client")
+		return
+	}
+
+	ref := &provider.Reference{
+		ResourceId: &itemID,
+	}
+
+	u, ok := revactx.ContextGetUser(ctx)
+	if !ok {
+		errorcode.GeneralException.Render(w, r, http.StatusUnauthorized, "User not found in context")
+		return
+	}
+
+	req := &provider.RemoveFavoriteRequest{
+		Ref:    ref,
+		UserId: u.Id,
+	}
+
+	res, err := gatewayClient.RemoveFavorite(ctx, req)
+	if err != nil {
+		g.logger.Error().Err(err).Msg("could not remove favorite")
+		errorcode.GeneralException.Render(w, r, http.StatusInternalServerError, "could not remove favorite")
+		return
+	}
+
+	switch res.Status.Code {
+	case rpc.Code_CODE_OK:
+		// continue
+	case rpc.Code_CODE_NOT_FOUND:
+		errorcode.InvalidRequest.Render(w, r, http.StatusBadRequest, "favorite not found")
+		return
+	default:
+		errorcode.GeneralException.Render(w, r, http.StatusInternalServerError, "could not remove favorite")
+		return
+	}
+
+	w.WriteHeader(http.StatusNoContent)
+}
diff --git a/services/graph/pkg/service/v0/service.go b/services/graph/pkg/service/v0/service.go
index f130de6dc1..ba87c73164 100644
--- a/services/graph/pkg/service/v0/service.go
+++ b/services/graph/pkg/service/v0/service.go
@@ -309,6 +309,8 @@ func NewService(opts ...Option) (Graph, error) { //nolint:maintidx
 				r.Route("/drive", func(r chi.Router) {
 					r.Get("/", svc.GetUserDrive)
 					r.Get("/root/children", svc.GetRootDriveChildren)
+					r.Post("/items/{itemID}/follow", svc.FollowDriveItem)
+					r.Delete("/following/{itemID}", svc.UnfollowDriveItem)
 				})
 				r.Get("/drives", svc.GetDrives(APIVersion_1))
 				r.Post("/changePassword", svc.ChangeOwnPassword)