471a1d657d
## Summary This PR enables the proof-of-concept resolver to backtrack by way of using the `pubgrub-rs` crate. Rather than using PubGrub as a _framework_ (implementing the `DependencyProvider` trait, letting PubGrub call us), I've instead copied over PubGrub's primary solver hook (which is only ~100 lines or so) and modified it for our purposes (e.g., made it async). There's a lot to improve here, but it's a start that will let us understand PubGrub's appropriateness for this problem space. A few observations: - In simple cases, the resolver is slower than our current (naive) resolver. I think it's just that the pipelining isn't as efficient as in the naive case, where we can just stream package and version fetches concurrently without any bottlenecks. - A lot of the code here relates to bridging PubGrub with our own abstractions -- so we need a `PubGrubPackage`, a `PubGrubVersion`, etc. |
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| .cargo | ||
| .github/workflows | ||
| crates | ||
| scripts/benchmarks | ||
| vendor/pubgrub | ||
| .gitignore | ||
| Cargo.lock | ||
| Cargo.toml | ||
| LICENSE-APACHE | ||
| LICENSE-MIT | ||
| README.md | ||
| rust-toolchain.toml | ||
puffin
An experimental Python packaging tool.
Motivation
Puffin is an extremely fast (experimental) Python package resolver and installer, intended to
replace pip and pip-tools (pip-compile and pip-sync).
Puffin itself is not a complete "package manager", but rather a tool for locking dependencies
(similar to pip-compile) and installing them (similar to pip-sync). Puffin can be used to
generate a set of locked dependencies from a requirements.txt file, and then install those
locked dependencies into a virtual environment.
Puffin represents an intermediary goal in our pursuit of building a "Cargo for Python": a Python
package manager that is extremely fast, reliable, and easy to use -- capable of replacing not only
pip, but also pipx, pip-tools, virtualenv, tox, setuptools, and even pyenv, by way of
managing the Python installation itself.
Puffin's limited scope allows us to solve many of the low-level problems that are required to
build such a package manager (like package installation) while shipping an immediately useful tool
with a minimal barrier to adoption. Try it today in lieu of pip and pip-tools.
Features
- Extremely fast dependency resolution and installation: install dependencies in sub-second time.
- Disk-space efficient: Puffin uses a global cache to deduplicate dependencies, and uses Copy-on-Write on supported filesystems to reduce disk usage.
Limitations
Puffin does not yet support:
- Source distributions
- VCS dependencies
- URL dependencies
- Uninstalling packages
- Windows
- ...
Like pip-compile, Puffin generates a platform-specific requirements.txt file (unlike, e.g.,
poetry, which generates a platform-agnostic poetry.lock file). As such, Puffin's
requirements.txt files are not portable across platforms and Python versions.
Usage
To resolve a requirements.in file:
cargo run -p puffin-cli -- compile requirements.in
To install from a resolved requirements.txt file:
cargo run -p puffin-cli -- sync requirements.txt
For more, see cargo run -p puffin-cli -- --help:
Usage: puffin-cli <COMMAND>
Commands:
compile Compile a `requirements.in` file to a `requirements.txt` file
sync Sync dependencies from a `requirements.txt` file
clean Clear the cache
freeze Enumerate the installed packages in the current environment
help Print this message or the help of the given subcommand(s)
Options:
-h, --help Print help
-V, --version Print version
License
Puffin is licensed under either of
- Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Puffin by you, as defined in the Apache-2.0 license, shall be dually licensed as above, without any additional terms or conditions.
