why my google app engine has domain name 'my-project.df.r.appspot.com'?

Have you seen this page yet?


There are several ways you can target different versions & services within a single GCP project.

However, most of them spell out -dot- instead of using an actual . and most of them have MY_PROJECT_ID as the thing before .appspot.com.

do you have multiple services or versions running in your environment?

EDIT - I found this in the Appengine Flex release notes:

App Engine is changing the URLs that you use to send requests to your apps. You can now include a region ID to help Google route your requests more efficiently and reliably. For example, an app can receive requests at https://PROJECT_ID.REGION_ID.r.appspot.com. This new URL is optional for existing apps, and will soon be required for all new apps.


I'm not seeing this happen to my flex service, but I am seeing it happen to my custom-runtime service. Is yours either of these?