https://cloud.google.com/shell/docs/using-web-preview#previewing_the_application

C++
git clone https://github.com/GoogleCloudPlatform/appengine-guestbook-python \
    && cd appengine-guestbook-python \
    && dev_appserver.py ./app.yaml
cd `mktemp -d` \
    && echo '<html><body>Hello World</body></html>' >./index.html \
    && python -m SimpleHTTPServer 8080

Source

Also in C++: