## Summary
Closes#1958
This adds linehaul metadata to uv's user-agent when pep 508 markers are
provided to the RegistryClientBuilder. Thanks to #2381, we were able to
leverage most information from markers and avoid inconsistency.
Linehaul is meant to be accompanying metadata pip sends in it's user
agent when talking to registries. You can see this output by running
something like `python -c 'from pip._internal.network.session import
user_agent; print(user_agent())'`.
In PyPI, this metadata processed by the
[linehaul-cloud-function](https://github.com/pypi/linehaul-cloud-function).
More info about linehaul can be found in #1958.
Below are some examples from pip:
* Linux GHA: `pip/24.0
{"ci":true,"cpu":"x86_64","distro":{"id":"jammy","libc":{"lib":"glibc","version":"2.35"},"name":"Ubuntu","version":"22.04"},"implementation":{"name":"CPython","version":"3.12.2"},"installer":{"name":"pip","version":"24.0"},"openssl_version":"OpenSSL
3.0.2 15 Mar
2022","python":"3.12.2","rustc_version":"1.76.0","system":{"name":"Linux","release":"6.5.0-1016-azure"}}`
* Windows GHA: `pip/24.0
{"ci":true,"cpu":"AMD64","implementation":{"name":"CPython","version":"3.12.2"},"installer":{"name":"pip","version":"24.0"},"openssl_version":"OpenSSL
3.0.13 30 Jan
2024","python":"3.12.2","rustc_version":"1.76.0","system":{"name":"Windows","release":"2022Server"}}`
* OSX GHA: `pip/24.0
{"ci":true,"cpu":"arm64","distro":{"name":"macOS","version":"14.2.1"},"implementation":{"name":"CPython","version":"3.12.2"},"installer":{"name":"pip","version":"24.0"},"openssl_version":"OpenSSL
3.0.13 30 Jan
2024","python":"3.12.2","rustc_version":"1.76.0","system":{"name":"Darwin","release":"23.2.0"}}`
Here's how uv results look like (sorry for the keys not having the same
order):
* Linux GHA: `uv/0.1.21
{"installer":{"name":"uv","version":"0.1.21"},"python":"3.12.2","implementation":{"name":"CPython","version":"3.12.2"},"distro":{"name":"Ubuntu","version":"22.04","id":"jammy","libc":null},"system":{"name":"Linux","release":"6.5.0-1016-azure"},"cpu":"x86_64","openssl_version":null,"setuptools_version":null,"rustc_version":null,"ci":true}`
* Windows GHA: `uv/0.1.21
{"installer":{"name":"uv","version":"0.1.21"},"python":"3.12.2","implementation":{"name":"CPython","version":"3.12.2"},"distro":null,"system":{"name":"Windows","release":"2022Server"},"cpu":"AMD64","openssl_version":null,"setuptools_version":null,"rustc_version":null,"ci":true}`
* OSX GHA: `uv/0.1.21
{"installer":{"name":"uv","version":"0.1.21"},"python":"3.12.2","implementation":{"name":"CPython","version":"3.12.2"},"distro":{"name":"macOS","version":"14.2.1","id":null,"libc":null},"system":{"name":"Darwin","release":"23.2.0"},"cpu":"arm64","openssl_version":null,"setuptools_version":null,"rustc_version":null,"ci":true}`
Distro information (such as the one pip uses `from pip._vendor import
distro` to retrieve instead of `platform` module) was not retrieved from
markers. Instead, the linux release codename/name/version uses
`sys-info` crate, adding about 50us of extra overhead on linux. The
distro osx version re-used the [mac_os version
implementation](99c992e38b/crates/platform-host/src/mac_os.rs)
from #2381 which adds about 20us of overhead on osx. I tried to use
other crates to avoid re-introducing `mac_os.rs` but most of them didn't
yield satisfactory performance (40ms-60ms~) or had the wrong values
needed (e.g. darwin version vs osx version).
I also didn't add libc retrieval or rustc retrieval as those seem to add
substantial overhead due to querying `ldd` or `rustc`. PyPy version
detection was also not added to avoid adding extra overhead to [support
PyPy for
linehaul](https://github.com/pypa/pip/blob/24.0/src/pip/_internal/network/session.py#L123).
All other behavior was kept 1-1 to match what pip's linehaul
implementation does (as of 24.0). This also aligns with what was
discussed in #1958.
## Test Plan
Added new integration test to uv-client.
---------
Co-authored-by: konstin <konstin@mailbox.org>
## Summary
Closes#1977
This allows us to send uv's version in the `uv-client` User Agent
header.
Here's how request headers look like to a server now:
```
...
Accept: application/vnd.pypi.simple.v1+json, application/vnd.pypi.simple.v1+html;q=0.2, text/html;q=0.01
User-Agent: uv/0.1.13
...
```
~~I went for a mix of Option 1 and 2 from #1977.~~ Open to alternative
naming as well, not tied too strongly here to the names picked.
~~Another possibility for this new crate is that we can use it to
consolidate metadata that exists across crates to ultimately be able to
create linehaul information described in #1958, but I haven't looked
into what those changes might look like.~~
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
<!-- How was it tested? -->
Added initial tests in the new crate to exercise its public API and
added a new test to uv-client to validate the headers using a 1-time
disposable server.
