can't access the index page with Google AppEngine

Question

When trying to visit the homepage of my website bob.com (just an example), I expect index.html to get displayed. Instead, I got a 404.

To reach index.html, I got to manually browse bob.com/index.html.

What did I do wrong with my current app.yaml ?

runtime: php
env: flex

runtime_config:
  document_root: ./index.html


handlers:

# Handle the main page by serving the index page.
# Note the $ to specify the end of the path, since app.yaml does prefix matching.
- url: /*
  static_files: index.html
  upload: index.html

Answer 1

This has done the trick:

runtime: php
env: flex

runtime_config:
  document_root: .
  front_controller_file: index.html