Add Caching Headers

[bbatsche]

All requests going through UPWARD PHP, including those for static files, include Cache-Control: no-store, no-cache, must-revalidate. There needs to be some better handling of response caching, especially for File & Directory Resolvers

• Determine what the appropriate caching policy should be
  • What should the cache lifetime be?
  • Should we include an ETag, or are those passé?
  • In what cases should a cache header be included or not?
• Add the appropriate cache headers
• What options should there be for disabling or clearing these headers (eg for development vs production)?

[manishparanjape]

We can define cache headers in upward.yml file.

Example
bundles:
  directory:
    inline: './dist'
  headers:
    inline:
      cache-control:
        inline: max-age=86400

in Resolver Class we can query and set these headers.

$headers    = $this->getIterator()->get('headers', $definition);
$response->getHeaders()->addHeaders($headers);

Will try this and update here.