Make `handle` column in remoteusers NULL

This alters the V6 migration to make the column NULLable. Anyone who has already run this migration will need to manually update their database.

activitypub.go

@@ -708,7 +708,8 @@ func federatePost(app *App, p *PublicPost, collID int64, isUpdate bool) error {
 
 func getRemoteUser(app *App, actorID string) (*RemoteUser, error) {
 	u := RemoteUser{ActorID: actorID}
-	err := app.db.QueryRow("SELECT id, inbox, shared_inbox, handle FROM remoteusers WHERE actor_id = ?", actorID).Scan(&u.ID, &u.Inbox, &u.SharedInbox, &u.Handle)
+	var handle sql.NullString
+	err := app.db.QueryRow("SELECT id, inbox, shared_inbox, handle FROM remoteusers WHERE actor_id = ?", actorID).Scan(&u.ID, &u.Inbox, &u.SharedInbox, &handle)
 	switch {
 	case err == sql.ErrNoRows:
 		return nil, impart.HTTPError{http.StatusNotFound, "No remote user with that ID."}
@@ -717,6 +718,8 @@ func getRemoteUser(app *App, actorID string) (*RemoteUser, error) {
 		return nil, err
 	}
 
+	u.Handle = handle.String
+
 	return &u, nil
 }
 

migrations/v6.go

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2019 A Bunch Tell LLC.
+ * Copyright © 2019-2020 A Bunch Tell LLC.
  *
  * This file is part of WriteFreely.
  *
@@ -13,7 +13,7 @@ package migrations
 func supportActivityPubMentions(db *datastore) error {
 	t, err := db.Begin()
 
-	_, err = t.Exec(`ALTER TABLE remoteusers ADD COLUMN handle ` + db.typeVarChar(255) + ` DEFAULT '' NOT NULL`)
+	_, err = t.Exec(`ALTER TABLE remoteusers ADD COLUMN handle ` + db.typeVarChar(255) + ` NULL`)
 	if err != nil {
 		t.Rollback()
 		return err