问题
Suppose I uploaded another version (say, "version: 2" in file app.yaml ) of my Google App Engine application. Version 1 is still the default and version 2 is for testing. How do I run it then?
回答1:
Once you upload a version on Appengine, you can switch between them easily.
Say that your app name is myapp, currently running version 1. You also have uploaded a version called 2-testing. Your default app (with version 1) can be reached by accessing myapp.appspot.com
If you wanted to access your versions explicitly, you joust need to access <version_name>-dot-myapp.appspot.com. Following the example it would be:
1-dot-myapp.appspot.com or 2-testing-dot-myapp.appspot.com
The -dot- is equivalent to <version>.<appname> but allows you to correctly serve a secure application with SSL
You can mark any version you want as default (serving myapp.appspot.com) using the admin console
edit: this is the official documentation page talking about domains and subdomains in Appengine
回答2:
Under versions in your admin console you can find the live uri of a version, if you select the version.
And you can use traffic splitting, where you can use your own client ip or a cookie to test a version. Docs: https://developers.google.com/appengine/docs/adminconsole/trafficsplitting
来源：https://stackoverflow.com/questions/17060867/google-app-engine-how-to-run-different-version