A slight rewrite of buildEnv which:
1. Makes buildEnv recursively add itself to its output, so that it can
be accessed from any php derivation.
2. Orders the extension text strings according to their internalDeps
attribute - dependencies have to be put before dependants in the
php.ini or they will fail to load due to missing symbols.
This moves yet more extensions from the base build to
phpPackages.ext. Some of the extensions are a bit quirky and need
patching for this to work, most notably mysqlnd and opcache.
Two new parameters are introduced for mkExtension - internalDeps and
postPhpize. internalDeps is used to specify which other internal
extensions the current extension depends on, in order to provide them
at build time. postPhpize is for when patches and quirks need to be
applied after running phpize.
Patch notes:
- For opcache, older versions of PHP have a bug where header files are
included in the wrong order.
- For mysqlnd, the config.h is never included, so we include it in the
main header file, mysqlnd.h. Also, the configure script doesn't add
the necessary library link flags, so we add them to the variable
configure should have added them to.
Also, add opcache to default extensions since it significantly
increases PHP's performance and is by default enabled on Debian based
distributions. Not having it enabled by default results in a puzzling
performance loss for anyone attempting to migrate from Debian/Ubuntu
to NixOS who is unaware of this. Therefore, enable it by default. /talyz
Upgrades Hydra to the latest master/flake branch. To perform this
upgrade, it's needed to do a non-trivial db-migration which provides a
massive performance-improvement[1].
The basic ideas behind multi-step upgrades of services between NixOS versions
have been gathered already[2]. For further context it's recommended to
read this first.
Basically, the following steps are needed:
* Upgrade to a non-breaking version of Hydra with the db-changes
(columns are still nullable here). If `system.stateVersion` is set to
something older than 20.03, the package will be selected
automatically, otherwise `pkgs.hydra-migration` needs to be used.
* Run `hydra-backfill-ids` on the server.
* Deploy either `pkgs.hydra-unstable` (for Hydra master) or
`pkgs.hydra-flakes` (for flakes-support) to activate the optimization.
The steps are also documented in the release-notes and in the module
using `warnings`.
`pkgs.hydra` has been removed as latest Hydra doesn't compile with
`pkgs.nixStable` and to ensure a graceful migration using the newly
introduced packages.
To verify the approach, a simple vm-test has been added which verifies
the migration steps.
[1] https://github.com/NixOS/hydra/pull/711
[2] https://github.com/NixOS/nixpkgs/pull/82353#issuecomment-598269471
