Allow customising the HTTP Cache-Control defaults.

[jedateach]

This is my proposed fix for #3501. It allows the default Cache-Control header to be customised using a yaml config array. You can choose true/false to enable or disable control settings, or you can set values.
For example:

HTTP:
  CacheControl:
    max-age: 0
    must-revalidate: true
    no-transform: false

Would produce Cache-Control: max-age=0, must-revalidate

EDIT: I've noticed that this would actually produce: Cache-Control: must-revalidate, because 0 is treated as false. Keen to hear thoughts before attempting to fix.

[willmorgan]

You need to do strict type checking here, because as you mentioned in your PR edit, not doing so produces buggy results.

If you could try to match the coding style prevalent in the rest of the framework - i.e. spaces in the right places - that'd be great.

[willmorgan]

So, I've had a look through. My view is 👍 for adding some level of configurability,

However, in order for this to go into 3.1, the default HTTP config settings will need to reflect the existing functionality - this is because there doesn't seem to be any opportunity elsewhere to override these configs, and HTTP::add_cache_headers is used in Controller->handleRequest, a pretty critical part of the framework.

Also, any chance you can write a few tests to confirm it conforms to your wonderful links? 😄

[dhensby]

@jedateach any progress on this?

[jedateach]

@dhensby no sorry - this is one of quite a few PRs to sort out at some stage.

[wilr]

e766658

[dhensby]

TESTS :(