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15883 commits

Author SHA1 Message Date
eldritch horrors e6cd67591b libexpr: rewrite the parser with pegtl instead of flex/bison
this gives about 20% performance improvements on pure parsing. obviously
it will be less on full eval, but depending on how much parsing is to be
done (e.g. including hackage-packages.nix or not) it's more like 4%-10%.

this has been tested (with thousands of core hours of fuzzing) to ensure
that the ASTs produced by the new parser are exactly the same as the old
one would have produced. error messages will change (sometimes by a lot)
and are not yet perfect, but we would rather leave this as is for later.

test results for running only the parser (excluding the variable binding
code) in a tight loop with inputs and parameters as given are promising:

  - 40% faster on lix's package.nix at 10000 iterations
  - 1.3% faster on nixpkgs all-packages.nix at 1000 iterations
  - equivalent on all of nixpkgs concatenated at 100 iterations
    (excluding invalid files, each file surrounded with parens)

more realistic benchmarks are somewhere in between the extremes, parsing
once again getting the largest uplift. other realistic workloads improve
by a few percentage points as well, notably system builds are 4% faster.

Benchmarks summary (from ./bench/summarize.jq bench/bench-*.json)
old/bin/nix --extra-experimental-features 'nix-command flakes' eval -f bench/nixpkgs/pkgs/development/haskell-modules/hackage-packages.nix
  mean:     0.408s ± 0.025s
            user: 0.355s | system: 0.033s
  median:   0.389s
  range:    0.388s ... 0.442s
  relative: 1

new/bin/nix --extra-experimental-features 'nix-command flakes' eval -f bench/nixpkgs/pkgs/development/haskell-modules/hackage-packages.nix
  mean:     0.332s ± 0.024s
            user: 0.279s | system: 0.033s
  median:   0.314s
  range:    0.313s ... 0.361s
  relative: 0.814

---

old/bin/nix --extra-experimental-features 'nix-command flakes' eval --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
  mean:     6.133s ± 0.022s
            user: 5.395s | system: 0.437s
  median:   6.128s
  range:    6.099s ... 6.183s
  relative: 1

new/bin/nix --extra-experimental-features 'nix-command flakes' eval --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
  mean:     5.925s ± 0.025s
            user: 5.176s | system: 0.456s
  median:   5.934s
  range:    5.861s ... 5.943s
  relative: 0.966

---

GC_INITIAL_HEAP_SIZE=10g old/bin/nix eval --extra-experimental-features 'nix-command flakes' --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
  mean:     4.503s ± 0.027s
            user: 3.731s | system: 0.547s
  median:   4.499s
  range:    4.478s ... 4.541s
  relative: 1

GC_INITIAL_HEAP_SIZE=10g new/bin/nix eval --extra-experimental-features 'nix-command flakes' --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
  mean:     4.285s ± 0.031s
            user: 3.504s | system: 0.571s
  median:   4.281s
  range:    4.221s ... 4.328s
  relative: 0.951

---

old/bin/nix --extra-experimental-features 'nix-command flakes' search --no-eval-cache github:nixos/nixpkgs/e1fa12d4f6c6fe19ccb59cac54b5b3f25e160870 hello
  mean:     16.475s ± 0.07s
            user: 14.088s | system: 1.572s
  median:   16.495s
  range:    16.351s ... 16.536s
  relative: 1

new/bin/nix --extra-experimental-features 'nix-command flakes' search --no-eval-cache github:nixos/nixpkgs/e1fa12d4f6c6fe19ccb59cac54b5b3f25e160870 hello
  mean:     15.973s ± 0.013s
            user: 13.558s | system: 1.615s
  median:   15.973s
  range:    15.946s ... 15.99s
  relative: 0.97

---

Change-Id: Ie66ec2d045dec964632c6541e25f8f0797319ee2
2024-06-25 12:24:58 +00:00
jade c097ebe66b Merge "Revert "libfetchers: make attribute / URL query handling consistent"" into main 2024-06-25 10:19:52 +00:00
jade 3e151d4d77 Revert "libfetchers: make attribute / URL query handling consistent"
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
2024-06-24 22:49:17 +00:00
jade d5637ee790 devShell: guard against running from another directory
I was working on nix-eval-jobs with a dev shell with some shenanigans to
run against a locally built Lix and it was getting really annoying when
`nix develop ../lix#` was messing up my other git repo's hooks.

This is a fix via blunt force, but it is at least obvious how it works.

Change-Id: Ia29eeb5be57ab6a2c88451c00ea18a51e4dfe65e
2024-06-24 13:41:38 -07:00
jade eb5de71adc justfile: accept extra options to just setup and pass them to meson
This lets you get the default options and still be able to add more.

Change-Id: Ife32c348b1498ff2ccdddf051a5bba520cfa36f0
2024-06-24 13:37:01 -07:00
Robert Hensing d86009bd76 Add build-dir setting, clean up default TMPDIR handling
This is a squash of upstream PRs #10303, #10312 and #10883.

fix: Treat empty TMPDIR as unset

Fixes an instance of

    nix: src/libutil/util.cc:139: nix::Path nix::canonPath(PathView, bool): Assertion `path != ""' failed.

... which I've been getting in one of my shells for some reason.
I have yet to find out why TMPDIR was empty, but it's no reason for
Nix to break.

(cherry picked from commit c3fb2aa1f9d1fa756dac38d3588c836c5a5395dc)

fix: Treat empty XDG_RUNTIME_DIR as unset

See preceding commit. Not observed in the wild, but is sensible
and consistent with TMPDIR behavior.

(cherry picked from commit b9e7f5aa2df3f0e223f5c44b8089cbf9b81be691)

local-derivation-goal.cc: Reuse defaultTempDir()

(cherry picked from commit fd31945742710984de22805ee8d97fbd83c3f8eb)

fix: remove usage of XDG_RUNTIME_DIR for TMP

(cherry picked from commit 1363f51bcb24ab9948b7b5093490a009947f7453)

tests/functional: Add count()

(cherry picked from commit 6221770c9de4d28137206bdcd1a67eea12e1e499)

Remove uncalled for message

(cherry picked from commit b1fe388d33530f0157dcf9f461348b61eda13228)

Add build-dir setting

(cherry picked from commit 8b16cced18925aa612049d08d5e78eccbf0530e4)
Change-Id: Ic7b75ff0b6a3b19e50a4ac8ff2d70f15c683c16a
2024-06-24 11:30:32 +03:00
Delan Azabani 4c3d93611f Merge "Fix build instructions in hacking.md and justfile" into main 2024-06-24 06:46:08 +00:00
Delan Azabani 37f276ba9d Merge "Fix compile error under gcc with -Denable-pch-std=false" into main 2024-06-24 06:45:40 +00:00
Delan Azabani 5d33e4cd59 Fix build instructions in hacking.md and justfile
The stdenv phases don’t actually do anything (at least not anymore),
and our justfile doesn’t behave the same as our docs.

This patch removes the stdenv phases from the docs, documents our
usage of just, and makes `just setup` heed `$mesonFlags`.

Fixes #413.
Fixes #414.

Change-Id: Ieb0b2a8ae420526238b5f9a73d7849ec6919995d
2024-06-24 12:55:00 +08:00
Delan Azabani 3baffbdcc5 Fix compile error under gcc with -Denable-pch-std=false
Following the latest hacking.md currently fails because of a missing
include in upstream editline. This patch fixes the build by adding
that missing include.

Fixes #410.

Change-Id: Iefd4cb687ed3da71ccda9fe9624f38e6ef4623e5
2024-06-24 12:47:04 +08:00
eldritch horrors d477b34d1d libutil: remove runProgram2 stdin functionality
this was only used in one place, and that place has been rewritten to
use a temporary file instead. keeping this around is not very helpful
at this time, and in any case we'd be better off rewriting subprocess
handling in rust where we not only have a much safer library for such
things but also async frameworks necessary for this easily available.

Change-Id: I6f8641b756857c84ae2602cdf41f74ee7a1fda02
2024-06-23 17:29:40 +00:00
eldritch horrors 2bbdaf0b19 libfetchers: write git commit message to tempfile
we want to remove runProgram's ability to provide stdin to a process
because the concurrency issues of handling both stdin and stdout are
much more pronounced once runProgram returns not is collected output
but a source. this is possible in the current c++ framework, however
it isn't necessary in almost all cases (as demonstrated by only this
single user existing) and in much better handled with a proper async
concurrency model that lets the caller handle both at the same time.

Change-Id: I29da1e1ad898d45e2e33a7320b246d5003e7712b
2024-06-23 17:29:40 +00:00
eldritch horrors 2fe9157808 flakes: add --commit-lock-file message test
we had no test to ensure that we generated a commit message at all?

Change-Id: Ic9aa8fde92b83e1ea6f61cd2a21867aa73d4e885
2024-06-23 17:29:40 +00:00
Qyriad 521e08cbde Merge changes I697f4f39,I9f25235d into main
* changes:
  doc-comment Fields for Activity and Result types
  mildly refactor the renderActivity if hell-chain
2024-06-23 16:55:36 +00:00
Maximilian Bosch 7c3b8229cc Merge "libstore: reduce loglevel of waiting for a machine to build" into main 2024-06-23 16:33:44 +00:00
Qyriad 701eb332bd doc-comment Fields for Activity and Result types
The ones we were able to figure out, at least.

Change-Id: I697f4f3942e35a7adf1b2a6cc28b3168d1de111c
2024-06-23 16:30:48 +00:00
Qyriad ce4dee0fa5 mildly refactor the renderActivity if hell-chain
This is primarily for readability, but iwrc chaining std::string's
operator+ is also pretty scuffed performance-wise, and this was doing a
lot of operator+ chainging.

Change-Id: I9f25235df153eb2bbb491f1ff7ebbeed9a8ec985
2024-06-23 16:30:38 +00:00
Maximilian Bosch 5f0062285c Merge "libfetchers: make attribute / URL query handling consistent" into main 2024-06-23 15:51:34 +00:00
eldritch horrors ce6cb14995 libutil: return Pid from startProcess, not pid_t
Change-Id: Icc8a15090c77f54ea7d9220aadedcd4a19922814
2024-06-23 11:52:49 +00:00
eldritch horrors 3d155fc509 libutil: give Pid proper resource semantics
copy-constructing or assigning from pid_t can easily lead to duplicate
Pid instances for the same process if a pid_t was used carelessly, and
Pid itself was copy-constructible. both could cause surprising results
such as killing processes twice (which could become very problemantic,
but luckily modern systems don't reuse PIDs all that quickly), or more
than one piece of the code believing it owns a process when neither do

Change-Id: Ifea7445f84200b34c1a1d0acc2cdffe0f01e20c6
2024-06-23 11:52:49 +00:00
eldritch horrors b43a2e84c4 libutil: make Pid -> pid_t operations explicit
Change-Id: I3137cc140590001fe7ba542844e735944a0a9255
2024-06-23 11:52:49 +00:00
eldritch horrors a9949f4760 libutil: add some serialize.hh serializer tests
Change-Id: I0116265a18bc44bba16c07bf419af70d5195f07d
2024-06-23 11:52:49 +00:00
eldritch horrors 39a1e248c9 libutil: remove sinkToSource eof callback
this is only used in one place, and only to set a nicer error message on
EndOfFile. the only caller that actually *catches* this exception should
provide an error message in that catch block rather than forcing support
for setting error message so deep into the stack. copyStorePath is never
called outside of PathSubstitutionGoal anyway, which catches everything.

Change-Id: Ifbae8706d781c388737706faf4c8a8b7917ca278
2024-06-23 11:52:49 +00:00
Artemis Tosini f80d95e36d Merge "libstore: Start creating LocalDerivationGoal subclasses" into main 2024-06-23 08:11:51 +00:00
Artemis Tosini 12f5d27363 libstore: Start creating LocalDerivationGoal subclasses
LocalDerivationGoal includes a large number of low-level sandboxing
primitives for Darwin and Linux, intermingled with ifdefs.
Start creating platform-specific classes to make it easier to add new
platforms and review platform-specific code.

This change only creates support infrastructure and moves two function,
more functions will be moved in future changes.

Change-Id: I9fc29fa2a7345107d4fc96c46fa90b4eabf6bb89
2024-06-23 03:33:07 +00:00
Qyriad fb8553f63c mildly cleanup ExprSelect::eval
Better variable names, some comments, and a slight logic rearrange.

Change-Id: I9685ae252f83217aa85f06432234159c9ad19d1c
2024-06-22 18:52:57 -06:00
Qyriad e09cc60df9 doc-comment ExprSelect's fields
Change-Id: I63e79991a4bab93421266785e9258e0f5bb89b8f
2024-06-22 18:52:57 -06:00
Maximilian Bosch fc6a1451af
libstore: reduce loglevel of waiting for a machine to build
This comes quite often when the available job slots on all remote
builders are exhausted and this is pretty spammy.

This isn't really an issue, but expected behavior.

A better way to display this is a nom-like approach where all scheduled
builds are shown in a tree and pending builds are being marked as such
IMHO.

Change-Id: I6bc14e6054f84e3eb0768127b490e263d8cdcf89
2024-06-22 17:38:25 +02:00
Maximilian Bosch 35eec921af
libfetchers: make attribute / URL query handling consistent
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
2024-06-22 14:42:43 +02:00
kloenk da4e46dd1f libmain: add progress bar with multiple status lines
Add the log-formats `multiline` and `multiline-with-logs` which offer
multiple current active building status lines.

Change-Id: Idd8afe62f8591b5d8b70e258c5cefa09be4cab03
2024-06-22 14:20:27 +02:00
Qyriad 21865ccce0 Merge "add a basic libmain test for the progress bar rendering" into main 2024-06-22 02:04:14 +00:00
jade 375f4c0337 Merge "libstore: remove operations that are never called by supported clients" into main 2024-06-21 20:46:18 +00:00
Qyriad fd250c51ed add a basic libmain test for the progress bar rendering
Hooray for leaky abstraction allowing us to test this particular part of
the render pipeline.

Change-Id: Ie0f251ff874f63324e6a9c6388b84ec6507eeae2
2024-06-20 13:56:53 -06:00
Qyriad e44dcd63c4 remove InstallableValueCommand class
Change-Id: Id12383f4741cba07159712700ebcfbe37e61560c
2024-06-20 17:00:06 +00:00
Qyriad 6515b1a495 de-inheritance CmdSearch for InstallableValueCommand
Change-Id: I125c8cac05c8e924b55e4eb1060496e35ea4e941
2024-06-20 17:00:06 +00:00
Qyriad 50be55ffca de-inheritance CmdEdit for InstallableValueCommand
Change-Id: If85ea78954a45470b0b25c08dc7d40bfebd53610
2024-06-20 17:00:06 +00:00
Qyriad 079eeb1de7 de-inheritance CmdRun for InstallableValueCommand
Change-Id: Ief858c1488197211e2ee8b70aa40ed6c65743558
2024-06-20 17:00:06 +00:00
Qyriad b9e9235ac0 de-inheritance CmdBundle for InstallableValueCommand
Change-Id: Icbac4ef927ddcaf0d2a74b376e5a77299529cd34
2024-06-20 17:00:06 +00:00
Qyriad 1e5f134560 de-inheritance CmdEval for InstallableValueCommand
Change-Id: I08b1702310e863d15de26dc838eb0bcb62417c10
2024-06-20 17:00:06 +00:00
Qyriad 8ba1939540 use a type alias for ProgressBar's chosen time point type
Change-Id: I621a455b1daba806fc498958aee7931fbfc55445
2024-06-20 15:24:27 +00:00
Qyriad f9594b592b extract ProgressBar declaration into its header file
Change-Id: Ica9e2ec41d99eaa196a0d535501edf45c589b2b6
2024-06-20 15:24:27 +00:00
Qyriad 3a4c21fc9e slight cleanup to ProgressBar::getStatus()
Binaries were identical before and after this commit on our machine

Change-Id: I6f8bfbe3298d6c5f43d5702c7a1e05cb180226cc
2024-06-20 15:24:27 +00:00
Ilya K 697ef65c14 Merge "BrotliDecompressionSource: don't bail out too early" into main 2024-06-20 07:06:52 +00:00
Ilya K 7d52d74bbe BrotliDecompressionSource: don't bail out too early
If we've consumed the entire input, that doesn't actually mean we're
done decompressing - there might be more output left. This worked (?)
in most cases because the input and output sizes are pretty comparable,
but sometimes they're not and then things get very funny.

Change-Id: I73435a654a911b8ce25119f713b80706c5783c1b
2024-06-20 09:21:13 +03:00
jade 6c29a2a6fc Merge "libstore: fix queryValidPaths concurrency" into main 2024-06-20 05:55:08 +00:00
jade 50472aa5be libstore: remove operations that are never called by supported clients
I did a whole bunch of `git log -S` to find out exactly when all these
things were obsoleted and found the commit in which their usage was
removed, which I have added in either the error message or a comment.

I've also made *some* of the version checks into static asserts for when
we update the minimum supported protocol version.

In the end this is not a lot of code we are deleting, but it's code that
we will never have to support into the future when we build a protocol
bridge, which is why I did it. It is not in the support baseline.

Change-Id: Iea3c80795c75ea74f328cf7ede7cbedf8c41926b
2024-06-19 19:41:04 -07:00
Eelco Dolstra fb7d315411 Merge pull request #10570 from layus/shared_caches
Share evaluation caches across installables

Before:

$ rm -rf ~/.cache/nix && time -f '%E' nix build --dry-run \
  'nixpkgs#hello' \
  'nixpkgs#clang' \
  'nixpkgs#cargo' \
  'nixpkgs#rustup' \
  'nixpkgs#bear' \
  'nixpkgs#firefox' \
  'nixpkgs#git-revise' \
  'nixpkgs#hyperfine' \
  'nixpkgs#curlie' \
  'nixpkgs#xz' \
  'nixpkgs#ripgrep'
0:03.61

After:

$ rm -rf ~/.cache/nix && time -f '%E' nix build --dry-run \
  'nixpkgs#hello' \
  'nixpkgs#clang' \
  'nixpkgs#cargo' \
  'nixpkgs#rustup' \
  'nixpkgs#bear' \
  'nixpkgs#firefox' \
  'nixpkgs#git-revise' \
  'nixpkgs#hyperfine' \
  'nixpkgs#curlie' \
  'nixpkgs#xz' \
  'nixpkgs#ripgrep'
0:01.46

This could probably use a more proper benchmark...

Fixes #313

(cherry picked from commit de51e5c335865e3e0a8cccd283fec1a52cce243f)
Change-Id: I9350bebd462b6af12c51db5bf432321abfe84a16
2024-06-19 18:39:11 +00:00
eldritch horrors c55dcc6c13 filetransfer: return a Source from download()
without this we will not be able to get rid of makeDecompressionSink,
which in turn will be necessary to get rid of sourceToSink (since the
libarchive archive wrapper *must* be a Source due to api limitations)

Change-Id: Iccd3d333ba2cbcab49cb5a1d3125624de16bce27
2024-06-19 10:50:12 +00:00
eldritch horrors 11f4a5bc7e libutil: return a source from readFile
don't consume a sink, return a source instead. the only reason to not do
this is a very slight reduction in dynamic allocations, but since we are
going to *at least* do disk io that will not be a lot of overhead anyway

Change-Id: Iae2f879ec64c3c3ac1d5310eeb6a85e696d4614a
2024-06-19 10:50:12 +00:00
eldritch horrors 67f778670c libutil: add makeDecompressionSource
Change-Id: Iac7f24d79e24417436b9b5cbefd6af051aeea0a6
2024-06-19 10:50:12 +00:00