How to set optional data page to route file?

Developer help Routing
#1

I created my routes.yaml as below,

routes:
  /about/:
    template: about
    data: page.about-page

It works fine when exists a page in the database which has slug is ‘about-page’. But i want to know, how to set data page optionally?

#2

Hey, there! Can you say more about what you’re trying to do?

#3

I’m trying to set static routing with getting meta details from a page. I want to get meta data from the page if exist on the database. else executing with default meta data.