[feature] Federate pinned posts (aka `featuredCollection`) in and out (#1560)

* start fiddling

* the ol' fiddle + update

* start working on fetching statuses

* poopy doopy doo where r u uwu

* further adventures in featuring statuses

* finishing up

* fmt

* simply status unpin loop

* move empty featured check back to caller function

* remove unnecessary log.WithContext calls

* remove unnecessary IsIRI() checks

* add explanatory comment about status URIs

* change log level to error

* better test names

1 files changed, 28 insertions, 0 deletions

diff --git a/internal/typeutils/internaltoas.go b/internal/typeutils/internaltoas.go
index 06b49c18f..bbcf6c84b 100644
--- a/internal/typeutils/internaltoas.go
+++ b/internal/typeutils/internaltoas.go
@@ -1296,6 +1296,34 @@ func (c *converter) OutboxToASCollection(ctx context.Context, outboxID string) (
 	return collection, nil
 }
 
+func (c *converter) StatusesToASFeaturedCollection(ctx context.Context, featuredCollectionID string, statuses []*gtsmodel.Status) (vocab.ActivityStreamsOrderedCollection, error) {
+	collection := streams.NewActivityStreamsOrderedCollection()
+
+	collectionIDProp := streams.NewJSONLDIdProperty()
+	featuredCollectionIDURI, err := url.Parse(featuredCollectionID)
+	if err != nil {
+		return nil, fmt.Errorf("error parsing url %s", featuredCollectionID)
+	}
+	collectionIDProp.SetIRI(featuredCollectionIDURI)
+	collection.SetJSONLDId(collectionIDProp)
+
+	itemsProp := streams.NewActivityStreamsOrderedItemsProperty()
+	for _, s := range statuses {
+		uri, err := url.Parse(s.URI)
+		if err != nil {
+			return nil, fmt.Errorf("error parsing url %s", s.URI)
+		}
+		itemsProp.AppendIRI(uri)
+	}
+	collection.SetActivityStreamsOrderedItems(itemsProp)
+
+	totalItemsProp := streams.NewActivityStreamsTotalItemsProperty()
+	totalItemsProp.Set(len(statuses))
+	collection.SetActivityStreamsTotalItems(totalItemsProp)
+
+	return collection, nil
+}
+
 func (c *converter) ReportToASFlag(ctx context.Context, r *gtsmodel.Report) (vocab.ActivityStreamsFlag, error) {
 	flag := streams.NewActivityStreamsFlag()