If this documentation is inaccurate in any way please do not hesitate to suggest corrections.
My understanding of this function is strictly from reading the source code and some limited experience implementing fetchers.
Previously we would completely refetch the submodules from the
network, even though the repo might already have them. Now we copy the
.git/modules directory from the repo as an optimisation. This speeds
up evaluating
builtins.fetchTree { type = "git"; url = "/path/to/blender"; submodules = true; }
(where /path/to/blender already has the needed submodules) from 121s
to 57s.
This is still pretty inefficient and a hack, but a better solution is
best done on the lazy-trees branch.
This change also help in the case where the repo already has the
submodules but the origin is unfetchable for whatever reason
(e.g. there have been cases where Nix in a GitHub action doesn't have
the right authentication set up).
We cannot use 'actualUrl', because for file:// repos that's not the
original URL that the repo was fetched from. This is a problem since
submodules may be relative to the original URL.
Fixes e.g.
nix eval --impure --json --expr 'builtins.fetchTree { type = "git"; url = "/path/to/blender"; submodules = true; }'
where /path/to/blender is a clone of
https://github.com/blender/blender.git (which has several relative
submodules like '../blender-addons.git').
With the switch to C++20, the rules became more strict, and we can no
longer initialize base classes. Make them comments instead.
(BTW
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2021/p2287r1.html
this offers some new syntax for this use-case. Hopefully this will be
adopted and we can eventually use it.)
If we don't have any github token, we won't be able to fetch private
repos, but we are also more likely to run into API limits since
we don't have a token. To mitigate this only ever use the github api
if we actually have a token.
nixos/nix#6290 introduced a regex pattern to account for tags when
resolving sourcehut refs. nixos/nix#4638 reafactored the code,
accidentally treating the pattern as a regular string, causing all
non-HEAD ref resolving to break.
This fixes the regression and adds more test cases to avoid future
breakage.
The git fetcher code used to dereference the (potentially empty) `ref`
input attribute. This was magically working, probably because the
compiler somehow outsmarted us, but is now blowing up with newer nixpkgs
versions.
Fix that by not trying to access this field while we don't know for sure
that it has been defined.
Fix#6554
Add a new `file` fetcher type, which will fetch a plain file over
http(s), or from the local file.
Because plain `http(s)://` or `file://` urls can already correspond to
`tarball` inputs (if the path ends-up with a know archive extension),
the URL parsing logic is a bit convuluted in that:
- {http,https,file}:// urls will be interpreted as either a tarball or a
file input, depending on the extensions of the path part (so
`https://foo.com/bar` will be a `file` input and
`https://foo.com/bar.tar.gz` as a `tarball` input)
- `file+{something}://` urls will be interpreted as `file` urls (with
the `file+` part removed)
- `tarball+{something}://` urls will be interpreted as `tarball` urls (with
the `tarball+` part removed)
Fix#3785
Co-Authored-By: Tony Olagbaiye <me@fron.io>
Since a26be9f3b8, the same parser is used
to parse the result of sourcehut’s `HEAD` endpoint (coming from [git
dumb protocol]) and the output of `git ls-remote`. However, they are very
slightly different (the former doesn’t specify the current reference
since it’s implied to be `HEAD`).
Unify both, and make the parser a bit more robust and understandable (by
making it more typed and adding tests for it)
[git dumb protocol]: https://git-scm.com/book/en/v2/Git-Internals-Transfer-Protocols#_the_dumb_protocol
I'm afraid I missed a few problematic `git(1)`-calls while implementing
PR #6440, sorry for that! Upon investigating what went wrong, I realized
that I only tested against the "cached"-case by accident because my
git-checkout with my system's flake was apparently cached during my
debugging.
I managed to trigger the original issue again by running:
$ git commit --allow-empty -m "tmp"
$ sudo nixos-rebuild switch --flake .# -L --builders ''
Since `repoDir` points to the checkout that's potentially owned by
another user, I decided to add `--git-dir` to each call affecting
`repoDir`.
Since the `tmpDir` for the temporary submodule-checkout is created by
Nix itself, it doesn't seem to be an issue.
Sorry for that, it should be fine now.
The previous head caching implementation stored two paths in the local
cache; one for the cached git repo and another textfile containing the
resolved HEAD ref. This commit instead stores the resolved HEAD by
setting the HEAD ref in the local cache appropriately.
The `--git-dir=` must be `.` in some cases (for cached repos that are
"bare" repos in `~/.cache/nix/gitv3`). With this fix we can add
`--git-dir` to each `git`-invokation needed for `nixos-rebuild`.
To demonstrate the problem:
* You need a `git` at 2.33.3 in your $PATH
* An expression like this in a git repository:
``` nix
{
outputs = { self, nixpkgs }: {
packages.foo.x86_64-linux = with nixpkgs.legacyPackages.x86_64-linux;
runCommand "snens" { } ''
echo ${(builtins.fetchGit ./.).lastModifiedDate} > $out
'';
};
}
```
Now, when instantiating the package via `builtins.getFlake`, it fails on
Nix 2.7 like this:
$ nix-instantiate -E '(builtins.getFlake "'"$(pwd)"'").packages.foo.x86_64-linux'
fatal: unsafe repository ('/nix/store/a7j3125km4h8l0p71q6ssfkxamfh5d61-source' is owned by someone else)
To add an exception for this directory, call:
git config --global --add safe.directory /nix/store/a7j3125km4h8l0p71q6ssfkxamfh5d61-source
error: program 'git' failed with exit code 128
(use '--show-trace' to show detailed location information)
This breaks e.g. `nixops`-deployments using flakes with similar
expressions as shown above.
The cause for this is that `git(1)` tries to find the highest
`.git`-directory in the directory tree and if it finds a such a
directory, but with another owning user (root vs. the user who evaluates
the expression), it fails as above. This was changed recently to fix
CVE-2022-24765[1].
By explicitly specifying `--git-dir`, Git assumes to be in the top-level
directory and doesn't attempt to look for a `.git`-directory in the
parent directories and thus the code-path leading to said error is never
reached.
[1] https://lore.kernel.org/git/xmqqv8veb5i6.fsf@gitster.g/
This was a problem when writing a fetcher that uses e.g. sha256 hashes
for revisions. This doesn't actually do anything new, but allows for
creating such fetchers in the future (perhaps when support for Git's
SHA256 object format gains more popularity).
The filter expects all paths to have a prefix of the raw `actualUrl`, but
`Store::addToStore(...)` provides absolute canonicalized paths.
To fix this create an absolute and canonicalized path from the `actualUrl` and
use it instead.
Fixes#6195.
When importing e.g. a local `nixpkgs` in a flake to test a change like
{
inputs.nixpkgs.url = path:/home/ma27/Projects/nixpkgs;
outputs = /* ... */
}
then the input is missing a `lastModified`-field that's e.g. used in
`nixpkgs.lib.nixosSystem`. Due to the missing `lastMoified`-field, the
mtime is set to 19700101:
result -> /nix/store/b7dg1lmmsill2rsgyv2w7b6cnmixkvc1-nixos-system-nixos-22.05.19700101.dirty
With this change, the `path`-fetcher now sets a `lastModified` attribute
to the `mtime` just like it's the case in the `tarball`-fetcher already.
When building NixOS systems with `nixpkgs` being a `path`-input and this
patch, the output-path now looks like this:
result -> /nix/store/ld2qf9c1s98dxmiwcaq5vn9k5ylzrm1s-nixos-system-nixos-22.05.20220217.dirty
Starting work on #5638
The exact boundary between `FetchSettings` and `EvalSettings` is not
clear to me, but that's fine. First lets clean out `libstore`, and then
worry about what, if anything, should be the separation between those
two.
diff-index operates on the view that git has of the working tree,
which might be outdated. The higher-level diff command does this
automatically. This change also adds handling for submodules.
fixes#4140
Alternative fixes would be invoking update-index before diff-index or
matching more closely what require_clean_work_tree from git-sh-setup.sh
does, but both those options make it more difficult to reason about
correctness.
The .git/refs/heads directory might be empty for a valid
usable git repository. This often happens in CI environments,
which might only fetch commits, not branches.
Therefore instead we let git itself check if HEAD points to
something that looks like a commit.
fixes#5302
- Previous to this commit the boundary was exclusive of the
top level flake.
- This is wrong since the top level flake is still a valid
relative reference.
- Now, the check boundary is inclusive of the top level flake.
Signed-off-by: Timothy DeHerrera <tim.deh@pm.me>
This fixes builtins.fetchGit { url = ...; ref = "HEAD"; }, that works in
stable nix (v2.3.10), but is broken in nix master:
$ ./result/bin/nix repl
Welcome to Nix version 2.4pre19700101_dd77f71. Type :? for help.
nix-repl> builtins.fetchGit { url = "https://github.com/NixOS/nix"; ref = "HEAD"; }
fetching Git repository 'https://github.com/NixOS/nix'fatal: couldn't find remote ref refs/heads/HEAD
error: program 'git' failed with exit code 128
The documentation for builtins.fetchGit says ref = "HEAD" is the
default, so it should also be supported to explicitly pass it.
I came across this issue because poetry2nix can use ref = "HEAD" in some
situations.
Fixes#4674.
Basically, if a tarball URL is used as a flake input, and the URL leads
to a redirect, the final redirect destination would be recorded as the
locked URL.
This allows tarballs under https://nixos.org/channels to be used as
flake inputs. If we, as before, lock on to the original URL it would
break every time the channel updates.
Local git repositories are normally used directly instead of
cloning. This commit checks if a repo is bare and forces a
clone.
Co-authored-by: Théophane Hufschmitt <regnat@users.noreply.github.com>
It appears as through the fetch attribute, which
is simply a variant with 3 elements, implicitly
converts boolean arguments to integers. One must
use Explicit<bool> to correctly populate it with
a boolean. This was missing from the implementation,
and resulted in clearly boolean JSON fields being
treated as numbers.
libc++10 seems to be stricter on what it allows in variant conversion.
I'm not sure what the rules are here, but this is the minimal change
needed to get through the compilation errors.
Sometimes it's necessary to fetch a git repository at a revision and
it's unknown which ref contains the revision in question. An example
would be a Cargo.lock which only provides the URL and the revision when
using a git repository as build input.
However it's considered a bad practice to perform a full checkout of a
repository since this may take a lot of time and can eat up a lot of
disk space. This patch makes a full checkout explicit by adding an
`allRefs` argument to `builtins.fetchGit` which fetches all refs if
explicitly set to true.
Closes#2409
A common pitfall when using e.g. `builtins.fetchGit` is the `fatal: not
a tree object`-error when trying to fetch a revision of a git-repository
that isn't on the `master` branch and no `ref` is specified.
In order to make clear what's the problem, I added a simple check
whether the revision in question exists and if it doesn't a more
meaningful error-message is displayed:
```
nix-repl> builtins.fetchGit { url = "https://github.com/owner/myrepo"; rev = "<commit not on master>"; }
moderror: --- Error -------------------------------------------------------------------- nix
Cannot find Git revision 'bf1cc5c648e6aed7360448a3745bb2fe4fbbf0e9' in ref 'master' of repository 'https://gitlab.com/Ma27/nvim.nix'! Please make sure that the rev exists on the ref you've specified or add allRefs = true; to fetchGit.
```
Closes#2431
Without setting HGPLAIN, the user's environment leaks into
hg invocations, which means that the output may not be in the
expected format.
HGPLAIN is the Mercurial-recommended solution for this in that
it's intended for uses by scripts and programs which are looking
to parse Mercurial's output in a consistent manner.
Fixes:
$ nix build --store /tmp/nix /home/eelco/Dev/patchelf#hydraJobs.build.x86_64-linux
warning: Git tree '/home/eelco/Dev/patchelf' is dirty
error: --- RestrictedPathError ------------------------------------------------------------------------------------------- nix
access to path '/tmp/nix/nix/store/xmkvfmffk7xfnazykb5kx999aika8an4-source/flake.nix' is forbidden in restricted mode
(use '--show-trace' to show detailed location information)
This change provides support for using access tokens with other
instances of GitHub and GitLab beyond just github.com and
gitlab.com (especially company-specific or foundation-specific
instances).
This change also provides the ability to specify the type of access
token being used, where different types may have different handling,
based on the forge type.
Since 108debef6f we allow a
`url`-attribute for the `github`-fetcher to fetch tarballs from
self-hosted `gitlab`/`github` instances.
However it's not used when defining e.g. a flake-input
foobar = {
type = "github";
url = "gitlab.myserver";
/* ... */
}
and breaks with an evaluation-error:
error: --- Error --------------------------------------nix
unsupported input attribute 'url'
(use '--show-trace' to show detailed location information)
This patch allows flake-inputs to be fetched from self-hosted instances
as well.
`nix flake info` calls the github 'commits' API, which requires
authorization when the repository is private. Currently this request
fails with a 404.
This commit adds an authorization header when calling the 'commits' API.
It also changes the way that the 'tarball' API authenticates, moving the
user's token from a query parameter into the Authorization header.
The query parameter method is recently deprecated and will be disallowed
in November 2020. Using them today triggers a warning email.
Directly register the store classes rather than a function to build an
instance of them.
This gives the possibility to introspect static members of the class or
choose different ways of instantiating them.
When the log.showSignature git setting is enabled, the output of
"git log" contains signature verification information in addition to the
timestamp GitInputScheme::fetch wants:
$ git log -1 --format=%ct
gpg: Signature made Sat 07 Sep 2019 02:02:03 PM PDT
gpg: using RSA key 0123456789ABCDEF0123456789ABCDEF01234567
gpg: issuer "user@example.com"
gpg: Good signature from "User <user@example.com>" [ultimate] 1567890123
1567890123
For folks that had log.showSignature set, this caused all nix operations
on flakes to fail:
$ nix build
error: stoull
The original idea was to implement a git-fetcher in Nix's core that
supports content hashes[1]. In #3549[2] it has been suggested to
actually use `fetchTree` for this since it's a fairly generic wrapper
over the new fetcher-API[3] and already supports content-hashes.
This patch implements a new git-fetcher based on `fetchTree` by
incorporating the following changes:
* Removed the original `fetchGit`-implementation and replaced it with an
alias on the `fetchTree` implementation.
* Ensured that the `git`-fetcher from `libfetchers` always computes a
content-hash and returns an "empty" revision on dirty trees (the
latter one is needed to retain backwards-compatibility).
* The hash-mismatch error in the fetcher-API exits with code 102 as it
usually happens whenever a hash-mismatch is detected by Nix.
* Removed the `flakes`-feature-flag: I didn't see a reason why this API
is so tightly coupled to the flakes-API and at least `fetchGit` should
remain usable without any feature-flags.
* It's only possible to specify a `narHash` for a `git`-tree if either a
`ref` or a `rev` is given[4].
* It's now possible to specify an URL without a protocol. If it's missing,
`file://` is automatically added as it was the case in the original
`fetchGit`-implementation.
[1] https://github.com/NixOS/nix/pull/3216
[2] https://github.com/NixOS/nix/pull/3549#issuecomment-625194383
[3] https://github.com/NixOS/nix/pull/3459
[4] https://github.com/NixOS/nix/pull/3216#issuecomment-553956703
Until now, the `gitlab`-fetcher determined the source's rev by checking
the latest commit of the given `ref` using the
`/repository/branches`-API.
This breaks however when trying to fetch a gitlab-repo by its tag:
```
$ nix repl
nix-repl> builtins.fetchTree gitlab:Ma27/nvim.nix/0.2.0
error: --- Error ------------------------------------------------------------------------------------- nix
unable to download 'https://gitlab.com/api/v4/projects/Ma27%2Fnvim.nix/repository/branches/0.2.0': HTTP error 404 ('')
```
When using the `/commits?ref_name`-endpoint[1] you can pass any kind of
valid ref to the `gitlab`-fetcher.
Please note that this fetches the only first 20 commits on a ref,
unfortunately there's currently no endpoint which only retrieves the
latest commit of any kind of `ref`.
[1] https://docs.gitlab.com/ee/api/commits.html#list-repository-commits
This allows you to refer to an input from another flake. For example,
$ nix run --inputs-from /path/to/hydra nixpkgs#hello
runs 'hello' from the 'nixpkgs' inputs of the 'hydra' flake.
Fixes#3769.
On nix-env -qa -f '<nixpkgs>', this reduces maximum RSS by 20970 KiB
and runtime by 0.8%. This is mostly because we're not parsing the hash
part as a hash anymore (just validating that it consists of base-32
characters).
Also, replace storePathToHash() by StorePath::hashPart().
fetchTarball, fetchTree, and fetchGit all have *optional* hash attrs.
This means that we need to be careful with what we allow to avoid
accidentally making these defaults. When ‘hash = ""’ we assume the
empty hash is wanted.
