nvchecker/nvchecker_source/opam.py
2024-12-20 09:34:45 +01:00

71 lines
2.3 KiB
Python

# MIT licensed
# Copyright (c) 2024 Daniel Peukert <daniel@peukert.cc>, et al.
import asyncio
from io import BytesIO
import tarfile
from typing import List
from nvchecker.api import (
session, VersionResult,
Entry, AsyncCache,
KeyManager, RichResult
)
OPAM_REPO_INDEX_URL = "%s/index.tar.gz"
OPAM_VERSION_PATH_PREFIX = "packages/%s/%s."
OPAM_VERSION_PATH_SUFFIX = "/opam"
OPAM_DEFAULT_REPO = 'https://opam.ocaml.org'
OPAM_DEFAULT_REPO_VERSION_URL = "%s/packages/%s/%s.%s"
def _decompress_and_list_files(data: bytes) -> List[str]:
# Convert the bytes to a file object and get a list of files
archive = tarfile.open(mode='r', fileobj=BytesIO(data))
return archive.getnames()
async def get_files(url: str) -> List[str]:
# Download the file and get its contents
res = await session.get(url)
data = res.body
# Get the file list of the archive
loop = asyncio.get_running_loop()
return await loop.run_in_executor(None, _decompress_and_list_files, data)
async def get_package_versions(files: List[str], pkg: str) -> List[str]:
# Prepare the filename prefix based on the package name
prefix = OPAM_VERSION_PATH_PREFIX % (pkg , pkg)
# Only keep opam files that are relevant to the package we're working with
filtered_files = []
for filename in files:
if filename.startswith(prefix) and filename.endswith(OPAM_VERSION_PATH_SUFFIX):
filtered_files.append(filename[len(prefix):-1*len(OPAM_VERSION_PATH_SUFFIX)])
return filtered_files
async def get_version(
name: str, conf: Entry, *,
cache: AsyncCache, keymanager: KeyManager,
**kwargs,
):
pkg = conf.get('pkg', name)
repo = conf.get('repo', OPAM_DEFAULT_REPO).rstrip('/')
# Get the list of files in the repo index (see https://opam.ocaml.org/doc/Manual.html#Repositories for repo structure)
files = await cache.get(OPAM_REPO_INDEX_URL % repo, get_files) # type: ignore
# Parse the version strings from the file names
raw_versions = await get_package_versions(files, pkg)
# Convert the version strings into RichResults
versions = []
for version in raw_versions:
versions.append(RichResult(
version = version,
# There is no standardised URL scheme, so we only return an URL for the default registry
url = OPAM_DEFAULT_REPO_VERSION_URL % (repo, pkg, pkg, version) if repo == OPAM_DEFAULT_REPO else None,
))
return versions