Fixes several correctness bugs primarily around modular services' recent
reload/notification options (#535695) and adds compliance coverage to guard them.
Fixes:
- `lib/services/service.nix`:
- the reload-conflict assertion had inverted polarity, so it fired on the
default configuration
- the `mkIf` guard on `process.reloadCommand` had a misplaced paren, applying
`!= null` to the `mkIf` result rather than to the condition
- `process.reloadSignal` derives `process.reloadCommand`, so the assertion
could not check `reloadCommand != null` -- that fired on every signal-only
service. The command is now derived at `mkDefault` priority and the
assertion is gated on `options.process.reloadCommand.highestPrio`, firing
only when the user also set `reloadCommand` explicitly.
- change `notificationProtocol` to a sub-module type
- `nixos/modules/system/service/systemd/service.nix`:
- `systemd.mainExecReload`'s default ran `escapeSystemdExecArgs` (a list
escaper) on the `nullOr str` `process.reloadCommand`; this threw
`expected a list but found a string` and would have mangled `$MAINPID`. It
now uses `process.reloadCommand` verbatim.
- the `Type` default read a non-existent
`config.serviceManager.notificationProtocol` instead of
`config.notificationProtocol`.
Tests:
Extend the modular-service compliance suite to guard the above:
- Portable (manager-agnostic) eval assertions: `reloadSignal` derives
`reloadCommand`, the conflict assertion does not fire on signal-only services
but does when both are set explicitly, and `notificationProtocol.systemd`/`.s6`
default to `false`.
- systemd-specific eval assertions: `serviceConfig.Type` (simple/notify) and
`serviceConfig.ExecReload` are asserted on the resolved host units. This
directly guards the `mainExecReload` fix, which threw before it.
- Runtime reload compliance test: a nested reloadable sub-service is started and
reloaded, asserting the service observed the reload (recorded a SIGHUP marker).
`callReload` receives the service's name path (the list of names from the
top-level service down to the target sub-service); each integration joins it
per its own unit-naming convention (NixOS dash-joins to the systemd unit name,
e.g. `reload-inner.service`). Keeping it a path list rather than a read-only
submodule option keeps the suite manager-agnostic.
- `doc/build-helpers/testers.chapter.md`: document `callReload`.
Follow-up to #535695.
Signed-off-by: cinereal <cinereal@riseup.net>
Assisted-by: Claude:claude-opus-4-8
Adds modular service option `process.environment` to pass an attrset of
env vars to the service manager.
`null` values actively unset the variable before the process starts.
Values are `coercedTo (either path package) str` via interpolation,
mirroring `pathOrStr`, so paths and packages render to store-path strings
with string context preserved. The type is `lazyAttrsOf`, allowing one
entry to reference another (recursive env definitions).
The systemd backend unsets entries using `unexport` in `ExecStart`,
so the variable is absent even when `Environment=` or
the inherited environment would otherwise supply it.
The systemd backend lifts non-null entries onto the primary unit wrapped
per-key with `lib.mkDefault` so they merge with the existing priority-100
`environment.PATH` binding in `nixos/lib/systemd-lib.nix` while still letting
explicit `systemd.service.environment.<k>` overrides win.
The systemd extra-root modules are loaded via `importApply`, closing `pkgs`
over `systemd/service.nix` as a non-module argument (matching the portable
`lib/services/service.nix` convention) instead of passing a redundant `pkgs`
specialArg. The docs eval threads `pkgs = throw` accordingly.
Portable coverage lives in `testers.modularServiceCompliance`: an eval-level
check that a set value round-trips and a `null` value is preserved, plus an
integration test that records the service's own `/proc/$$/environ` and asserts
the set variable is present and the null variable is absent. The
systemd-specific grep assertions in `systemd/test.nix` cover how systemd
achieves this (`Environment=` rendering, null filtering, the `unexport`
wrapper, and override precedence).
Assisted-by: Claude:claude-opus-4-8
Portable test suite for modular services, designed to be usable with
other service managers and use cases, inside Nixpkgs and externally.
Like modular services itself, it's still quite bare-bones. New
features can crystallize around this kind of infrastructure.
Assisted-By: Claude Opus 4.7/4.8 era Claude models
Lychee by itself does not have a way to explicitly declare the
intent for the site to be relocatable.
Recent-ish changes in lychee and/or its dependencies have made
it catch the a root reference in all mdbook 404.html pages,
which is quite confusing.
By improving the UX around this aspect of the site, we resolve
at least part of that confusion.
(Though mdbook users should probably exclude the 404 page)
Allows ignoring file metadata differences (permissions, ownership)
when comparing files.
This is especially useful on darwin, where we often run into subtle
issues like:
-Device: 1,23 Access: (0444/-r--r--r--) Uid: ( 0/ root) Gid: ( 0/ wheel)
+Device: 1,23 Access: (0444/-r--r--r--) Uid: ( 0/ root) Gid: ( 350/ nixbld)
Add an optional postFailureMessage parameter to testEqualContents that allows
users to provide additional context when tests fail. This is particularly useful
for providing instructions on how to update expected results when they change
intentionally.
The message is displayed after the standard failure output, helping maintainers
understand what to do next when a test fails.
