How to configure app.yaml on GAE with PHP

Question

I'm getting stuck in configuring app.yaml on GAE in order to redirect in PHP code. I'd like to redirect to another HTML page called thanks.html in thanks/thanks.html directory after pushing submit button in index.php. However, it redirects to index.php from index.php With the current settings. I think PHP code don't detect my thanks.html. So I'd like to ask you what point is wrong on my app.yaml and should I use dispatch.yaml?? Thank you so much. Except redirecting, other functions are working fine.

my directory structure is

index.php(only the part of redirect to thanks.html)

header("Location: ./thanks/thanks.html");
exit();

app.yaml

runtime: php72
handlers:
- url: /(.*\.(gif|png|jpg))$
  static_files: \1
  upload: .+\.(gif|png|jpg)$

- url: /css
  static_dir: css

- url: /js
  static_dir: js

- url: .*
  script: auto
  http_headers:

- url: /thanks
  static_dir: /thanks

env_variables:
        SENDGRID_API_KEY: "*********"
        DEVELOPER_EMAIL: "********" 

Answer 1

You will need to deploy a front controller to handle all request routing in App Engine. Deploy with the codes below:

index.php :

<?php
header("Location: ./thanks/thanks.html");
exit();
switch (@parse_url($_SERVER['REQUEST_URI'])['path']) {
    case '/':
        require 'index.php';
        break;
    case 'thanks/thanks.html':
        require 'thanks.html';
        break;
    default:
        http_response_code(404);
        exit('Not Found');
}
?>