This PR adds initial support for [rkyv] to puffin. In particular,
the main aim here is to make puffin-client's `SimpleMetadata` type
possible to deserialize from a `&[u8]` without doing any copies. This
PR **stops short of actuallying doing that zero-copy deserialization**.
Instead, this PR is about adding the necessary trait impls to a variety
of types, along with a smattering of small refactorings to make rkyv
possible to use.
For those unfamiliar, rkyv works via the interplay of three traits:
`Archive`, `Serialize` and `Deserialize`. The usual flow of things is
this:
* Make a type `T` implement `Archive`, `Serialize` and `Deserialize`.
rkyv
helpfully provides `derive` macros to make this pretty painless in most
cases.
* The process of implementing `Archive` for `T` *usually* creates an
entirely
new distinct type within the same namespace. One can refer to this type
without naming it explicitly via `Archived<T>` (where `Archived` is a
clever
type alias defined by rkyv).
* Serialization happens from `T` to (conceptually) a `Vec<u8>`. The
serialization format is specifically designed to reflect the in-memory
layout
of `Archived<T>`. Notably, *not* `T`. But `Archived<T>`.
* One can then get an `Archived<T>` with no copying (albeit, we will
likely
need to incur some cost for validation) from the previously created
`&[u8]`.
This is quite literally [implemented as a pointer cast][rkyv-ptr-cast].
* The problem with an `Archived<T>` is that it isn't your `T`. It's
something
else. And while there is limited interoperability between a `T` and an
`Archived<T>`, the main issue is that the surrounding code generally
demands
a `T` and not an `Archived<T>`. **This is at the heart of the tension
for
introducing zero-copy deserialization, and this is mostly an intrinsic
problem to the technique and not an rkyv-specific issue.** For this
reason,
given an `Archived<T>`, one can get a `T` back via an explicit
deserialization step. This step is like any other kind of
deserialization,
although generally faster since no real "parsing" is required. But it
will
allocate and create all necessary objects.
This PR largely proceeds by deriving the three aforementioned traits
for `SimpleMetadata`. And, of course, all of its type dependencies. But
we stop there for now.
The main issue with carrying this work forward so that rkyv is actually
used to deserialize a `SimpleMetadata` is figuring out how to deal
with `DataWithCachePolicy` inside of the cached client. Ideally, this
type would itself have rkyv support, but adding it is difficult. The
main difficulty lay in the fact that its `CachePolicy` type is opaque,
not easily constructable and is internally the tip of the iceberg of
a rat's nest of types found in more crates such as `http`. While one
"dumb"-but-annoying approach would be to fork both of those crates
and add rkyv trait impls to all necessary types, it is my belief that
this is the wrong approach. What we'd *like* to do is not just use
rkyv to deserialize a `DataWithCachePolicy`, but we'd actually like to
get an `Archived<DataWithCachePolicy>` and make actual decisions used
the archived type directly. Doing that will require some work to make
`Archived<DataWithCachePolicy>` directly useful.
My suspicion is that, after doing the above, we may want to mush
forward with a similar approach for `SimpleMetadata`. That is, we want
`Archived<SimpleMetadata>` to be as useful as possible. But right
now, the structure of the code demands an eager conversion (and thus
deserialization) into a `SimpleMetadata` and then into a `VersionMap`.
Getting rid of that eagerness is, I think, the next step after dealing
with `DataWithCachePolicy` to unlock bigger wins here.
There are many commits in this PR, but most are tiny. I still encourage
review to happen commit-by-commit.
[rkyv]: https://rkyv.org/
[rkyv-ptr-cast]:
https://docs.rs/rkyv/latest/src/rkyv/util/mod.rs.html#63-68
This allows us to enforce type safety within the resolver. For example,
in the index, we can remove `String` as a key type and enforce that
callers _must_ present us with a `PackageId`. (This actually caught one
bug, where we were using the SHA rather than the package ID. That bug
shouldn't have had any effect given where it was, since those are 1:1,
but it's still problematic.)
## Summary
Now, `puffin_warnings::warn_once` and `puffin_warnings::warn` will go to
`stderr`, as long as the user isn't running under `--quiet`. Previously,
these went through `tracing`, and so were only visible when running
under `--verbose`.
## Summary
This PR modifies the cache structure in a few ways. Most notably, we now
shard the set of registry wheels by package, and index them lazily when
computing the install plan.
This applies both to built wheels:
<img width="989" alt="Screen Shot 2023-12-06 at 4 42 19 PM"
src="0e8a306f-befd-4be9-a63e-2303389837bb">
And remote wheels:
<img width="836" alt="Screen Shot 2023-12-06 at 4 42 30 PM"
src="7fd908cd-dd86-475e-9779-07ed067b4a1a">
For other distributions, we now consistently cache using the package
name, which is really just for clarity and debuggability (we could
consider omitting these):
<img width="955" alt="Screen Shot 2023-12-06 at 4 58 30 PM"
src="3e8d0f99-df45-429a-9175-d57b54a72e56">
Obliquely closes https://github.com/astral-sh/puffin/issues/575.
Ran `cargo upgrade --incompatible`, seems there are no changes required.
From cacache 0.12.0:
> BREAKING CHANGE: some signatures for copy have changed, and copy no
longer automatically reflinks
`which` 5.0.0 seems to have only error message changes.
`PackageName` and `ExtraName` can now only be constructed from valid
names. They share the same rules, so i gave them the same
implementation. Constructors are split between `new` (owned) and
`from_str` (borrowed), with the owned version avoiding allocations.
Closes#279
---------
Co-authored-by: Zanie <contact@zanie.dev>
From
https://packaging.python.org/en/latest/specifications/recording-installed-packages/#recording-installed-packages
> This directory is named as {name}-{version}.dist-info, with name and
version fields corresponding to Core metadata specifications. Both
fields must be normalized (see Package name normalization and PEP 440
for the definition of normalization for each field respectively), and
replace dash (-) characters with underscore (_) characters, so the
.dist-info directory always has exactly one dash (-) character in its
stem, separating the name and version fields.
Follow up to #278
The normalized name abstractions were not consistently, this PR uses
them where they were previously missing:
* `WheelFilename::distribution`
* `Requirement::name`
* `Requirement::extras`
* `Metadata21::name`
* `Metadata21::provides_dist`
With `puffin-package` depending on `pep508_rs` this would be cyclical
crate dependency, so `puffin-normalize` gets split out from
`puffin-package`.
`DistInfoName` has the same task and semantics as `PackageName`, so it's
merged into the latter.
`PackageName` and `ExtraName` documentation is moved onto the type and
their constructors are called `new` instead of `normalize`. We now use
these constructors rarely enough the implicit allocation by
`to_string()` shouldn't matter anymore, while more actual cloning
becomes visible.
