Use RC5 image

[withinboredom]

This migrates to the new RC5 image instead of cloning master of php-src.

New image sizes:

• alpine: 60.14 MiB
• debian: 190.31 MiB

[dunglas]

🎉

[withinboredom]

During this, I discovered that the alpine image doesn't have --enable-embed in the php Dockerfile. I left a comment on docker-library/php#1331 (review), but this will likely need an issue on that repo to track it.

[back-2-95]

@withinboredom That docker-library/php#1331 is merged

[back-2-95]

@withinboredom Few questions:

• If we now have no need to clone any php-src branch why we need to build php in php-base stage?
• If final stage extends from php-base, it has all the dev stuff needed for building in it. Extra weight?

In other words, if we're now happy with official PHP RC5 as it is, we should just build FrankenPHP and then combine it with clean PHP RC5 ? Just trying to understand what I'm reading from the Dockerfile diff.

[withinboredom]

If we now have no need to clone any php-src branch why we need to build php in php-base stage?

It's pretty much explicitly needed for alpine (#74 (comment)), and I left it in for both platforms so we can control the build of PHP, which is desirable since it appears getting "bugfix" PRs merged to the base image can take awhile. This gives us some independence from their release cycle and keeps things consistent.

If final stage extends from php-base, it has all the dev stuff needed for building in it. Extra weight?

I think this is normal? The "dev stuff" is required to build extensions, right? There shouldn't be anything not already in the original image (except for libphp in the alpine image).

I suspect the build of PHP does contribute to some image size increase (I'm not 100% sure how Docker does deduping -- especially without a zfs backend); however, that should be negligible once you start piling extensions on the image. For example, one of my internal images adds another 200mb of extensions and several hundred megs in assets. So the cost of storage is negligible when compared to a final image.

[back-2-95]

First one 👍

Second, the "dev stuff": it it's needed for the final product (to eg. run some operations) then it's argumented.
If some packages were installed just for the time being (building stuff), then it should be either removed or use multistage (where you don't need to worry about cleaning up as you just copy the outcome = build stuff).

Still, your image sizes seem quite small already so I'm not totally sure if something happened already (cleaning).

[back-2-95]

Alpine docker file has at least these:

• docker-php-source delete
• apk del --no-network .build-deps

Bullseye has some savedAptMark with a comment reset apt-mark's "manual" list so that "purge --auto-remove" will remove all build dependencies

so there is cleaning 👍