How to define custom cache lifetime for custom content elements?

Question

Shouldn't TypoScript cache work for custom content elements like this:

tt_content {
    my_custom_element =< lib.contentElement
    my_custom_element {
        // tested also with stdWrap.cache
        cache {
            key = my_custom_element
            // 10 seconds to test
            lifetime = 10
        }
        templateName = MyCustomElement
        dataProcessing.10 = Example\Project\DataProcessing\FetchDataProcessor
        dataProcessing.10 {
            fetchUri = https://www.example.com/resource
            as = fetched_data
        }
    }
}

...or do I interpret it the wrong way?
https://docs.typo3.org/m/typo3/reference-typoscript/master/en-us/Functions/Cache.html
I would expect to define a custom cache lifetime for this content element.

Answer 1

Possible solution:

tt_content {
    // COA_INT to ensure the block .my_custom_element isn't cached
    my_custom_element = COA_INT
    my_custom_element {
        10 =< lib.contentElement
        10 {
            // Re-add cache for the block .10
            cache {
                // Use UID of content element when user can edit content of it
                key = my_custom_element_{field:uid}
                key.insertData = 1
                // For test currently 10 seconds
                lifetime = 10
            }
            templateName = MyCustomElement
            dataProcessing.10 = Example\Project\DataProcessing\FetchDataProcessor
            dataProcessing.10 {
                fetchUri = https://www.example.com/resource
                as = fetched_data
            }
        }
    }
}

BUT it has (huge) drawbacks:

• The page HTML, where the content element is placed on, won't be cached by the browser.
• And a static file cache extension won't work for this pages too.