I saw warnings when we were e.g. unzipping wheel and setuptools in two
tasks at the same time. We now keep track of in flight unzips.
This introduces a `OnceMap` abstraction which we also use in the
resolver.
## Summary
When installing a local wheel, we need to avoid removing the zipped
wheel (since it lives outside of the cache), _and_ need to ensure that
we unzip the wheel into the cache (rather than replacing the zipped
wheel, which may even live outside of the project).
Closes https://github.com/astral-sh/puffin/issues/553.
It turns out that it's not uncommon to use timestamps as patch versions
(e.g., `20230628214621`). I believe this is the ISO 8601 "basic format".
These can't be represented by a `u32`, so I think it makes sense to just
bump to `u64` to remove this limitation.
After this change, two wheel caches remain: `built-wheels-v0` and
`wheels-v0`, docs screenshots below. Each contains both the wheel
metadata, cache policy and zip or unzipped wheels under the same name.
The zipped/unzipped strategy is as follows: In `pip-compile`, when we
build a wheel, we store it zipped. When `pip-sync` or a source dist
build in `pip-compile` need to install the wheel, we unzip it, remove
the file and replace it with the unzipped wheel.
This removes `WheelCache` and `UrlIndex` in favor of `Cache` plus
`WheelCache`. The non-built wheel cache now considers index urls and the
url for url wheels.
I'm unsure if we need the `Unzipper` type, this could just be a
function.
I move `no_index` into `IndexUrls` and started using `IndexUrl` up to
the clap level.
I left a number of TODOs in the code, namely performing the actual
invalidation of unzipped wheels and making the `InstallPlan` understand
cache invalidation (i.e. uninstall wheels when their remote changed).
## Summary and motivation
For a given source dist, we store the metadata of each wheel built
through it in `built-wheel-metadata-v0/pypi/<source dist
filename>/metadata.json`. During resolution, we check the cache status
of the source dist. If it is fresh, we check `metadata.json` for a
matching wheel. If there is one we use that metadata, if there isn't, we
build one. If the source is stale, we build a wheel and override
`metadata.json` with that single wheel. This PR thereby ties the local
built wheel metadata cache to the freshness of the remote source dist.
This functionality is available through `SourceDistCachedBuilder`.
`puffin_installer::Builder`, `puffin_installer::Downloader` and
`Fetcher` are removed, instead there are now `FetchAndBuild` which calls
into the also new `SourceDistCachedBuilder`. `FetchAndBuild` is the new
main high-level abstraction: It spawns parallel fetching/building, for
wheel metadata it calls into the registry client, for wheel files it
fetches them, for source dists it calls `SourceDistCachedBuilder`. It
handles locks around builds, and newly added also inter-process file
locking for git operations.
Fetching and building source distributions now happens in parallel in
`pip-sync`, i.e. we don't have to wait for the largest wheel to be
downloaded to start building source distributions.
In a follow-up PR, I'll also clear built wheels when they've become
stale.
Another effect is that in a fully cached resolution, we need neither zip
reading nor email parsing.
Closes#473
## Source dist cache structure
Entries by supported sources:
* `<build wheel metadata cache>/pypi/foo-1.0.0.zip/metadata.json`
* `<build wheel metadata
cache>/<sha256(index-url)>/foo-1.0.0.zip/metadata.json`
* `<build wheel metadata
cache>/url/<sha256(url)>/foo-1.0.0.zip/metadata.json`
But the url filename does not need to be a valid source dist filename
(<https://github.com/search?q=path%3A**%2Frequirements.txt+master.zip&type=code>),
so it could also be the following and we have to take any string as
filename:
* `<build wheel metadata
cache>/url/<sha256(url)>/master.zip/metadata.json`
Example:
```text
# git source dist
pydantic-extra-types @ git+https://github.com/pydantic/pydantic-extra-types.git
# pypi source dist
django_allauth==0.51.0
# url source dist
werkzeug @ ff1904eb5e2853bf83db817a7dd53d/werkzeug-3.0.1.tar.gz
```
will be stored as
```text
built-wheel-metadata-v0
├── git
│ └── 5c56bc1c58c34c11
│ └── 843b753e9e8cb74e83cac55598719b39a4d5ef1f
│ └── metadata.json
├── pypi
│ └── django-allauth-0.51.0.tar.gz
│ └── metadata.json
└── url
└── 6781bd6440ae72c2
└── werkzeug-3.0.1.tar.gz
└── metadata.json
```
The inside of a `metadata.json`:
```json
{
"data": {
"django_allauth-0.51.0-py3-none-any.whl": {
"metadata-version": "2.1",
"name": "django-allauth",
"version": "0.51.0",
...
}
}
}
```
## Summary
This PR unifies the behavior that lived in the resolver's `distribution`
crates with the behaviors that were spread between the various structs
in the installer crate into a single `Fetcher` struct that is intended
to manage all interactions with distributions. Specifically, the
interface of this struct is such that it can access distribution
metadata, download distributions, return those downloads, etc., all with
a common cache.
Overall, this is mostly just DRYing up code that was repeated between
the two crates, and putting it behind a reasonable shared interface.
Charlie Marsh
konsti