Page doesn't contain HIT in cache header

Question

I am publishing my magento extension but in the revision I was notified of the issue:

Does anyone have any useful help?

Answer 1

It seems you've added cacheable="false" on some block located in product view page i.e. catalog_product_view.xml due to which cache is getting disabled for entire product view page as mentioned here - https://devdocs.magento.com/guides/v2.3/extension-dev-guide/cache/page-caching.html

Cacheable and uncacheable are terms we use to indicate whether or not a page should be cached at all. (By default, all pages are cacheable.) If any block in a layout is designated as uncacheable, the entire page is uncacheable.

So, you must work on some workaround to disable cache for your own block if you had done cacheable="false" intentionally i.e hole punching in magento full page cache.

I good start will be https://stackoverflow.com/questions/9120413/how-do-i-include-a-dynamic-block-in-the-product-page-with-full-page-caching-turn/9125519#9125519

Answer 2

FYI if your not using layout / view and still get this problem see

how to set no-cache HTTP headers in controller in magento 2

this is how you can set your controller/observer to use no cache and avoid this error