The original attempt at this introduced a regression; this commit
reverts the revert and fixes the regression.
This reverts commit 3e151d4d77.
Fix to the regression:
flakeref: fix handling of `?dir=` param for flakes in subdirs
As reported in #419[1], accessing a flake in a subdir of a Git
repository fails with the previous commit[2] applied with the error
error: unsupported Git input attribute 'dir'
The problem is that the `dir`-param is inserted into the parsed URL if a
flake is fetched from the subdir of a Git repository. However, for the
fetching part this isn't even needed. The fix is to just pass `subdir`
as second argument to `FlakeRef` (which needs a `basedir` that can be
empty) and leave the parsedURL as-is.
Added a regression test to make sure we don't run into this again.
[1] https://git.lix.systems/lix-project/lix/issues/419
[2] e22172aaf6b6a366cecd3c025590e68fa2b91bcc,
originally 3e151d4d77
Change-Id: I2c72d5a32e406a7ca308e271730bd0af01c5d18b
We previously allowed you to map any flake URL to any other flake URL,
including shorthand flakerefs, indirect flake URLs like `flake:nixpkgs`,
direct flake URLs like `github:NixOS/nixpkgs`, or local paths.
But flake registry entries mapping from direct flake URLs often come
from swapping the 'from' and 'to' arguments by accident, and even when
created intentionally, they may not actually work correctly.
This patch rejects those URLs (and fully-qualified flake: URLs), making
it harder to swap the arguments by accident.
Fixes#181.
Change-Id: I24713643a534166c052719b8770a4edfcfdb8cf3
This reverts commit 35eec921af.
Reason for revert: Regressed nix-eval-jobs, and it appears to be this change is buggy/missing a case. It just needs another pass.
Code causing the problem in n-e-j, when invoked with `nix-eval-jobs --flake '.#hydraJobs'`:
```
n-e-j/tests/assets » ../../build/src/nix-eval-jobs --meta --workers 1 --flake .#hydraJobs
warning: unknown setting 'trusted-users'
warning: `--gc-roots-dir' not specified
error: unsupported Git input attribute 'dir'
error: worker error: error: unsupported Git input attribute 'dir'
```
```
nix::Value *vRoot = [&]() {
if (args.flake) {
auto [flakeRef, fragment, outputSpec] =
nix::parseFlakeRefWithFragmentAndExtendedOutputsSpec(
args.releaseExpr, nix::absPath("."));
nix::InstallableFlake flake{
{}, state, std::move(flakeRef), fragment, outputSpec,
{}, {}, args.lockFlags};
return flake.toValue(*state).first;
} else {
return releaseExprTopLevelValue(*state, autoArgs, args);
}
}();
```
Inspecting the program behaviour reveals that `dir` was in fact set in the URL going into the fetcher. This is in turn because unlike in the case changed in this commit, it was not erased before handing it to libfetchers, which is probably just a mistake.
```
(rr) up
3 0x00007ffff60262ae in nix::fetchers::Input::fromURL (url=..., requireTree=requireTree@entry=true) at src/libfetchers/fetchers.cc:39
warning: Source file is more recent than executable.
39 auto res = inputScheme->inputFromURL(url, requireTree);
(rr) p url
$1 = (const nix::ParsedURL &) @0x7fffdc874190: {url = "git+file:///home/jade/lix/nix-eval-jobs",
base = "git+file:///home/jade/lix/nix-eval-jobs", scheme = "git+file", authority = std::optional<std::string> = {[contained value] = ""},
path = "/home/jade/lix/nix-eval-jobs", query = std::map with 1 element = {["dir"] = "tests/assets"}, fragment = ""}
(rr) up
4 0x00007ffff789d904 in nix::parseFlakeRefWithFragment (url=".#hydraJobs", baseDir=std::optional<std::string> = {...},
allowMissing=allowMissing@entry=false, isFlake=isFlake@entry=true) at src/libexpr/flake/flakeref.cc:179
warning: Source file is more recent than executable.
179 FlakeRef(Input::fromURL(parsedURL, isFlake), getOr(parsedURL.query, "dir", "")),
(rr) p parsedURL
$2 = {url = "git+file:///home/jade/lix/nix-eval-jobs", base = "git+file:///home/jade/lix/nix-eval-jobs", scheme = "git+file",
authority = std::optional<std::string> = {[contained value] = ""}, path = "/home/jade/lix/nix-eval-jobs", query = std::map with 1 element = {
["dir"] = "tests/assets"}, fragment = ""}
(rr) list
174
175 if (pathExists(flakeRoot + "/.git/shallow"))
176 parsedURL.query.insert_or_assign("shallow", "1");
177
178 return std::make_pair(
179 FlakeRef(Input::fromURL(parsedURL, isFlake), getOr(parsedURL.query, "dir", "")),
180 fragment);
181 }
```
Change-Id: Ib55a882eaeb3e59228857761dc1e3b2e366b0f5e
The original idea was to fix lix#174, but for a user friendly solution,
I figured that we'd need more consistency:
* Invalid query params will cause an error, just like invalid
attributes. This has the following two consequences:
* The `?dir=`-param from flakes will be removed before the URL to be
fetched is passed to libfetchers.
* The tarball fetcher doesn't allow URLs with custom query params
anymore. I think this was questionable anyways given that an
arbitrary set of query params was silently removed from the URL you
wanted to fetch. The correct way is to use an attribute-set
with a key `url` that contains the tarball URL to fetch.
* Same for the git & mercurial fetchers: in that case it doesn't even
matter though: both fetchers added unused query params to the URL
that's passed from the input scheme to the fetcher (`url2` in the code).
It turns out that this was never used since the query parameters were
erased again in `getActualUrl`.
* Validation happens for both attributes and URLs. Previously, a lot of
fetchers validated e.g. refs/revs only when specified in a URL and
the validity of attribute names only in `inputFromAttrs`.
Now, all the validation is done in `inputFromAttrs` and `inputFromURL`
constructs attributes that will be passed to `inputFromAttrs`.
* Accept all attributes as URL query parameters. That also includes
lesser used ones such as `narHash`.
And "output" attributes like `lastModified`: these could be declared
already when declaring inputs as attribute rather than URL. Now the
behavior is at least consistent.
Personally, I think we should differentiate in the future between
"fetched input" (basically the attr-set that ends up in the lock-file)
and "unfetched input" earlier: both inputFrom{Attrs,URL} entrypoints
are probably OK for unfetched inputs, but for locked/fetched inputs
a custom entrypoint should be used. Then, the current entrypoints
wouldn't have to allow these attributes anymore.
Change-Id: I1be1992249f7af8287cfc37891ab505ddaa2e8cd
These now have equivalents in the standard lib in C++20. This change was
performed with a custom clang-tidy check which I will submit later.
Executed like so:
ninja -C build && run-clang-tidy -checks='-*,nix-*' -load=build/libnix-clang-tidy.so -p .. -fix ../tests | tee -a clang-tidy-result
Change-Id: I62679e315ff9e7ce72a40b91b79c3e9fc01b27e9
Types converted:
- `NixStringContextElem`
- `OutputsSpec`
- `ExtendedOutputsSpec`
- `DerivationOutput`
- `DerivationType`
Existing ones mostly conforming the pattern cleaned up:
- `ContentAddressMethod`
- `ContentAddressWithReferences`
The `DerivationGoal::derivationType` field had a bogus initialization,
now caught, so I made it `std::optional`. I think #8829 can make it
non-optional again because it will ensure we always have the derivation
when we construct a `DerivationGoal`.
See that issue (#7479) for details on the general goal.
`git grep 'Raw::Raw'` indicates the two types I didn't yet convert
`DerivedPath` and `BuiltPath` (and their `Single` variants) . This is
because @roberth and I (can't find issue right now...) plan on reworking
them somewhat, so I didn't want to churn them more just yet.
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
Special-casing the file name is rather ugly, so we shouldn't do
that. So now any {file,http,https} URL is handled by
TarballInputScheme, except for non-flake inputs (i.e. inputs that have
the attribute `flake = false`).
`DerivedPath::Built` and `DerivationGoal` were previously using a
regular set with the convention that the empty set means all outputs.
But it is easy to forget about this rule when processing those sets.
Using `OutputSpec` forces us to get it right.
The registry targets generally follow a URL formatting schema with
support for a query parameter of "?dir=subpath" to specify a sub-path
location below the URL root.
Alternatively, an absolute path can be specified. This specification
mode accepts the query parameter but ignores/drops it. It would
probably be better to either (a) disallow the query parameter for the
path form, or (b) recognize the query parameter and add to the path.
This patch implements (b) for consistency, and to make it easier for
tooling that might switch between a remote git reference and a local
path reference.
See also issue #4050.
The attributes previously stored in TreeInfo (narHash, revCount,
lastModified) are now stored in Input. This makes it less arbitrary
what attributes are stored where.
As a result, the lock file format has changed. An entry like
"info": {
"lastModified": 1585405475,
"narHash": "sha256-bESW0n4KgPmZ0luxvwJ+UyATrC6iIltVCsGdLiphVeE="
},
"locked": {
"owner": "NixOS",
"repo": "nixpkgs",
"rev": "b88ff468e9850410070d4e0ccd68c7011f15b2be",
"type": "github"
},
is now stored as
"locked": {
"owner": "NixOS",
"repo": "nixpkgs",
"rev": "b88ff468e9850410070d4e0ccd68c7011f15b2be",
"type": "github",
"lastModified": 1585405475,
"narHash": "sha256-bESW0n4KgPmZ0luxvwJ+UyATrC6iIltVCsGdLiphVeE="
},
The 'Input' class is now a dumb set of attributes. All the fetcher
implementations subclass InputScheme, not Input. This simplifies the
API.
Also, fix substitution of flake inputs. This was broken since lazy
flake fetching started using fetchTree internally.
In particular, doing 'nix build /path/to/dir' now works if
/path/to/dir is not a Git tree (it only has to contain a flake.nix
file).
Also, 'nix flake init' no longer requires a Git tree (but it will do a
'git add flake.nix' if it's a Git tree)
When computing a lock file, we now respect the lock files of flake
inputs. This is important for usability / reproducibility. For
example, the 'nixops' flake depends on the 'nixops-aws' and
'nixops-hetzner' repositories. So when the 'nixops' flake is used in
another flake, we want the versions of 'nixops-aws' and
'nixops-hetzner' locked by the the 'nixops' flake because those
presumably have been tested.
This can lead to a proliferation of versions of flakes like 'nixpkgs'
(since every flake's lock file could depend on a different version of
'nixpkgs'). This is not a major issue when using Nixpkgs overlays or
NixOS modules, since then the top-level flake composes those
overlays/modules into *its* version of Nixpkgs and all other versions
are ignored. Lock file computation has been made a bit more lazy so it
won't try to fetch all those versions of 'nixpkgs'.
However, in case it's necessary to minimize flake versions, there now
are two input attributes that allow this. First, you can copy an input
from another flake, as follows:
inputs.nixpkgs.follows = "dwarffs/nixpkgs";
This states that the calling flake's 'nixpkgs' input shall be the same
as the 'nixpkgs' input of the 'dwarffs' input.
Second, you can override inputs of inputs:
inputs.nixpkgs.url = github:edolstra/nixpkgs/<hash>;
inputs.nixops.inputs.nixpkgs.url = github:edolstra/nixpkgs/<hash>;
or equivalently, using 'follows':
inputs.nixpkgs.url = github:edolstra/nixpkgs/<hash>;
inputs.nixops.inputs.nixpkgs.follows = "nixpkgs";
This states that the 'nixpkgs' input of the 'nixops' input shall be
the same as the calling flake's 'nixpkgs' input.
Finally, at '-v' Nix now prints the changes to the lock file, e.g.
$ nix flake update ~/Misc/eelco-configurations/hagbard
inputs of flake 'git+file:///home/eelco/Misc/eelco-configurations?subdir=hagbard' changed:
updated 'nixpkgs': 'github:edolstra/nixpkgs/7845bf5f4b3013df1cf036e9c9c3a55a30331db9' -> 'github:edolstra/nixpkgs/03f3def66a104a221aac8b751eeb7075374848fd'
removed 'nixops'
removed 'nixops/nixops-aws'
removed 'nixops/nixops-hetzner'
removed 'nixops/nixpkgs'
For example, if the top-level flake depends on
"nixpkgs/release-19.03", and one of its dependencies depends on
"nixpkgs", then the latter will be mapped to "nixpkgs/release-19.03",
rather than whatever the default branch of "nixpkgs" is. Thus you get
only one "nixpkgs" dependency rather than two.
This currently only works in a breadth-first way, so the other way
around (i.e. if the top-level flake depends on "nixpkgs", and a
dependency depends on "nixpkgs/release-19.03") still results in two
"nixpkgs" dependencies.
So you now get
$ nix build
error: path '.' is not a flake (because it does not reference a Git repository)
rather than
$ nix build
error: unsupported argument '.'