prepare.py 19.6 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568
"""Prepares a distribution for installation
"""

# The following comment should be removed at some point in the future.
# mypy: strict-optional=False

import logging
import mimetypes
import os
import shutil

from pip._vendor import requests
from pip._vendor.six import PY2

from pip._internal.distributions import (
    make_distribution_for_install_requirement,
)
from pip._internal.distributions.installed import InstalledDistribution
from pip._internal.exceptions import (
    DirectoryUrlHashUnsupported,
    HashMismatch,
    HashUnpinned,
    InstallationError,
    PreviousBuildDirError,
    VcsHashUnsupported,
)
from pip._internal.utils.filesystem import copy2_fixed
from pip._internal.utils.hashes import MissingHashes
from pip._internal.utils.logging import indent_log
from pip._internal.utils.misc import (
    display_path,
    hide_url,
    path_to_display,
    rmtree,
)
from pip._internal.utils.temp_dir import TempDirectory
from pip._internal.utils.typing import MYPY_CHECK_RUNNING
from pip._internal.utils.unpacking import unpack_file
from pip._internal.vcs import vcs

if MYPY_CHECK_RUNNING:
    from typing import (
        Callable, List, Optional, Tuple,
    )

    from mypy_extensions import TypedDict

    from pip._internal.distributions import AbstractDistribution
    from pip._internal.index.package_finder import PackageFinder
    from pip._internal.models.link import Link
    from pip._internal.network.download import Downloader
    from pip._internal.req.req_install import InstallRequirement
    from pip._internal.req.req_tracker import RequirementTracker
    from pip._internal.utils.hashes import Hashes

    if PY2:
        CopytreeKwargs = TypedDict(
            'CopytreeKwargs',
            {
                'ignore': Callable[[str, List[str]], List[str]],
                'symlinks': bool,
            },
            total=False,
        )
    else:
        CopytreeKwargs = TypedDict(
            'CopytreeKwargs',
            {
                'copy_function': Callable[[str, str], None],
                'ignore': Callable[[str, List[str]], List[str]],
                'ignore_dangling_symlinks': bool,
                'symlinks': bool,
            },
            total=False,
        )

logger = logging.getLogger(__name__)


def _get_prepared_distribution(
        req,  # type: InstallRequirement
        req_tracker,  # type: RequirementTracker
        finder,  # type: PackageFinder
        build_isolation  # type: bool
):
    # type: (...) -> AbstractDistribution
    """Prepare a distribution for installation.
    """
    abstract_dist = make_distribution_for_install_requirement(req)
    with req_tracker.track(req):
        abstract_dist.prepare_distribution_metadata(finder, build_isolation)
    return abstract_dist


def unpack_vcs_link(link, location):
    # type: (Link, str) -> None
    vcs_backend = vcs.get_backend_for_scheme(link.scheme)
    assert vcs_backend is not None
    vcs_backend.unpack(location, url=hide_url(link.url))


class File(object):
    def __init__(self, path, content_type):
        # type: (str, str) -> None
        self.path = path
        self.content_type = content_type


def get_http_url(
    link,  # type: Link
    downloader,  # type: Downloader
    download_dir=None,  # type: Optional[str]
    hashes=None,  # type: Optional[Hashes]
):
    # type: (...) -> File
    temp_dir = TempDirectory(kind="unpack", globally_managed=True)
    # If a download dir is specified, is the file already downloaded there?
    already_downloaded_path = None
    if download_dir:
        already_downloaded_path = _check_download_dir(
            link, download_dir, hashes
        )

    if already_downloaded_path:
        from_path = already_downloaded_path
        content_type = mimetypes.guess_type(from_path)[0]
    else:
        # let's download to a tmp dir
        from_path, content_type = _download_http_url(
            link, downloader, temp_dir.path, hashes
        )

    return File(from_path, content_type)


def _copy2_ignoring_special_files(src, dest):
    # type: (str, str) -> None
    """Copying special files is not supported, but as a convenience to users
    we skip errors copying them. This supports tools that may create e.g.
    socket files in the project source directory.
    """
    try:
        copy2_fixed(src, dest)
    except shutil.SpecialFileError as e:
        # SpecialFileError may be raised due to either the source or
        # destination. If the destination was the cause then we would actually
        # care, but since the destination directory is deleted prior to
        # copy we ignore all of them assuming it is caused by the source.
        logger.warning(
            "Ignoring special file error '%s' encountered copying %s to %s.",
            str(e),
            path_to_display(src),
            path_to_display(dest),
        )


def _copy_source_tree(source, target):
    # type: (str, str) -> None
    target_abspath = os.path.abspath(target)
    target_basename = os.path.basename(target_abspath)
    target_dirname = os.path.dirname(target_abspath)

    def ignore(d, names):
        # type: (str, List[str]) -> List[str]
        skipped = []  # type: List[str]
        if d == source:
            # Pulling in those directories can potentially be very slow,
            # exclude the following directories if they appear in the top
            # level dir (and only it).
            # See discussion at https://github.com/pypa/pip/pull/6770
            skipped += ['.tox', '.nox']
        if os.path.abspath(d) == target_dirname:
            # Prevent an infinite recursion if the target is in source.
            # This can happen when TMPDIR is set to ${PWD}/...
            # and we copy PWD to TMPDIR.
            skipped += [target_basename]
        return skipped

    kwargs = dict(ignore=ignore, symlinks=True)  # type: CopytreeKwargs

    if not PY2:
        # Python 2 does not support copy_function, so we only ignore
        # errors on special file copy in Python 3.
        kwargs['copy_function'] = _copy2_ignoring_special_files

    shutil.copytree(source, target, **kwargs)


def get_file_url(
    link,  # type: Link
    download_dir=None,  # type: Optional[str]
    hashes=None  # type: Optional[Hashes]
):
    # type: (...) -> File
    """Get file and optionally check its hash.
    """
    # If a download dir is specified, is the file already there and valid?
    already_downloaded_path = None
    if download_dir:
        already_downloaded_path = _check_download_dir(
            link, download_dir, hashes
        )

    if already_downloaded_path:
        from_path = already_downloaded_path
    else:
        from_path = link.file_path

    # If --require-hashes is off, `hashes` is either empty, the
    # link's embedded hash, or MissingHashes; it is required to
    # match. If --require-hashes is on, we are satisfied by any
    # hash in `hashes` matching: a URL-based or an option-based
    # one; no internet-sourced hash will be in `hashes`.
    if hashes:
        hashes.check_against_path(from_path)

    content_type = mimetypes.guess_type(from_path)[0]

    return File(from_path, content_type)


def unpack_url(
    link,  # type: Link
    location,  # type: str
    downloader,  # type: Downloader
    download_dir=None,  # type: Optional[str]
    hashes=None,  # type: Optional[Hashes]
):
    # type: (...) -> Optional[File]
    """Unpack link into location, downloading if required.

    :param hashes: A Hashes object, one of whose embedded hashes must match,
        or HashMismatch will be raised. If the Hashes is empty, no matches are
        required, and unhashable types of requirements (like VCS ones, which
        would ordinarily raise HashUnsupported) are allowed.
    """
    # non-editable vcs urls
    if link.is_vcs:
        unpack_vcs_link(link, location)
        return None

    # If it's a url to a local directory
    if link.is_existing_dir():
        if os.path.isdir(location):
            rmtree(location)
        _copy_source_tree(link.file_path, location)
        return None

    # file urls
    if link.is_file:
        file = get_file_url(link, download_dir, hashes=hashes)

    # http urls
    else:
        file = get_http_url(
            link,
            downloader,
            download_dir,
            hashes=hashes,
        )

    # unpack the archive to the build dir location. even when only downloading
    # archives, they have to be unpacked to parse dependencies
    unpack_file(file.path, location, file.content_type)

    return file


def _download_http_url(
    link,  # type: Link
    downloader,  # type: Downloader
    temp_dir,  # type: str
    hashes,  # type: Optional[Hashes]
):
    # type: (...) -> Tuple[str, str]
    """Download link url into temp_dir using provided session"""
    download = downloader(link)

    file_path = os.path.join(temp_dir, download.filename)
    with open(file_path, 'wb') as content_file:
        for chunk in download.chunks:
            content_file.write(chunk)

    if hashes:
        hashes.check_against_path(file_path)

    return file_path, download.response.headers.get('content-type', '')


def _check_download_dir(link, download_dir, hashes):
    # type: (Link, str, Optional[Hashes]) -> Optional[str]
    """ Check download_dir for previously downloaded file with correct hash
        If a correct file is found return its path else None
    """
    download_path = os.path.join(download_dir, link.filename)

    if not os.path.exists(download_path):
        return None

    # If already downloaded, does its hash match?
    logger.info('File was already downloaded %s', download_path)
    if hashes:
        try:
            hashes.check_against_path(download_path)
        except HashMismatch:
            logger.warning(
                'Previously-downloaded file %s has bad hash. '
                'Re-downloading.',
                download_path
            )
            os.unlink(download_path)
            return None
    return download_path


class RequirementPreparer(object):
    """Prepares a Requirement
    """

    def __init__(
        self,
        build_dir,  # type: str
        download_dir,  # type: Optional[str]
        src_dir,  # type: str
        wheel_download_dir,  # type: Optional[str]
        build_isolation,  # type: bool
        req_tracker,  # type: RequirementTracker
        downloader,  # type: Downloader
        finder,  # type: PackageFinder
        require_hashes,  # type: bool
        use_user_site,  # type: bool
    ):
        # type: (...) -> None
        super(RequirementPreparer, self).__init__()

        self.src_dir = src_dir
        self.build_dir = build_dir
        self.req_tracker = req_tracker
        self.downloader = downloader
        self.finder = finder

        # Where still-packed archives should be written to. If None, they are
        # not saved, and are deleted immediately after unpacking.
        self.download_dir = download_dir

        # Where still-packed .whl files should be written to. If None, they are
        # written to the download_dir parameter. Separate to download_dir to
        # permit only keeping wheel archives for pip wheel.
        self.wheel_download_dir = wheel_download_dir

        # NOTE
        # download_dir and wheel_download_dir overlap semantically and may
        # be combined if we're willing to have non-wheel archives present in
        # the wheelhouse output by 'pip wheel'.

        # Is build isolation allowed?
        self.build_isolation = build_isolation

        # Should hash-checking be required?
        self.require_hashes = require_hashes

        # Should install in user site-packages?
        self.use_user_site = use_user_site

    @property
    def _download_should_save(self):
        # type: () -> bool
        if not self.download_dir:
            return False

        if os.path.exists(self.download_dir):
            return True

        logger.critical('Could not find download directory')
        raise InstallationError(
            "Could not find or access download directory '{}'"
            .format(self.download_dir))

    def prepare_linked_requirement(
        self,
        req,  # type: InstallRequirement
    ):
        # type: (...) -> AbstractDistribution
        """Prepare a requirement that would be obtained from req.link
        """
        assert req.link
        link = req.link

        # TODO: Breakup into smaller functions
        if link.scheme == 'file':
            path = link.file_path
            logger.info('Processing %s', display_path(path))
        else:
            logger.info('Collecting %s', req.req or req)

        download_dir = self.download_dir
        if link.is_wheel and self.wheel_download_dir:
            # when doing 'pip wheel` we download wheels to a
            # dedicated dir.
            download_dir = self.wheel_download_dir

        if link.is_wheel:
            if download_dir:
                # When downloading, we only unpack wheels to get
                # metadata.
                autodelete_unpacked = True
            else:
                # When installing a wheel, we use the unpacked
                # wheel.
                autodelete_unpacked = False
        else:
            # We always delete unpacked sdists after pip runs.
            autodelete_unpacked = True

        with indent_log():
            # Since source_dir is only set for editable requirements.
            assert req.source_dir is None
            req.ensure_has_source_dir(self.build_dir, autodelete_unpacked)
            # If a checkout exists, it's unwise to keep going.  version
            # inconsistencies are logged later, but do not fail the
            # installation.
            # FIXME: this won't upgrade when there's an existing
            # package unpacked in `req.source_dir`
            if os.path.exists(os.path.join(req.source_dir, 'setup.py')):
                raise PreviousBuildDirError(
                    "pip can't proceed with requirements '{}' due to a"
                    " pre-existing build directory ({}). This is "
                    "likely due to a previous installation that failed"
                    ". pip is being responsible and not assuming it "
                    "can delete this. Please delete it and try again."
                    .format(req, req.source_dir)
                )

            # Now that we have the real link, we can tell what kind of
            # requirements we have and raise some more informative errors
            # than otherwise. (For example, we can raise VcsHashUnsupported
            # for a VCS URL rather than HashMissing.)
            if self.require_hashes:
                # We could check these first 2 conditions inside
                # unpack_url and save repetition of conditions, but then
                # we would report less-useful error messages for
                # unhashable requirements, complaining that there's no
                # hash provided.
                if link.is_vcs:
                    raise VcsHashUnsupported()
                elif link.is_existing_dir():
                    raise DirectoryUrlHashUnsupported()
                if not req.original_link and not req.is_pinned:
                    # Unpinned packages are asking for trouble when a new
                    # version is uploaded. This isn't a security check, but
                    # it saves users a surprising hash mismatch in the
                    # future.
                    #
                    # file:/// URLs aren't pinnable, so don't complain
                    # about them not being pinned.
                    raise HashUnpinned()

            hashes = req.hashes(trust_internet=not self.require_hashes)
            if self.require_hashes and not hashes:
                # Known-good hashes are missing for this requirement, so
                # shim it with a facade object that will provoke hash
                # computation and then raise a HashMissing exception
                # showing the user what the hash should be.
                hashes = MissingHashes()

            try:
                local_file = unpack_url(
                    link, req.source_dir, self.downloader, download_dir,
                    hashes=hashes,
                )
            except requests.HTTPError as exc:
                logger.critical(
                    'Could not install requirement %s because of error %s',
                    req,
                    exc,
                )
                raise InstallationError(
                    'Could not install requirement {} because of HTTP '
                    'error {} for URL {}'.format(req, exc, link)
                )

            # For use in later processing, preserve the file path on the
            # requirement.
            if local_file:
                req.local_file_path = local_file.path

            abstract_dist = _get_prepared_distribution(
                req, self.req_tracker, self.finder, self.build_isolation,
            )

            if download_dir:
                if link.is_existing_dir():
                    logger.info('Link is a directory, ignoring download_dir')
                elif local_file:
                    download_location = os.path.join(
                        download_dir, link.filename
                    )
                    if not os.path.exists(download_location):
                        shutil.copy(local_file.path, download_location)
                        logger.info(
                            'Saved %s', display_path(download_location)
                        )

            if self._download_should_save:
                # Make a .zip of the source_dir we already created.
                if link.is_vcs:
                    req.archive(self.download_dir)
        return abstract_dist

    def prepare_editable_requirement(
        self,
        req,  # type: InstallRequirement
    ):
        # type: (...) -> AbstractDistribution
        """Prepare an editable requirement
        """
        assert req.editable, "cannot prepare a non-editable req as editable"

        logger.info('Obtaining %s', req)

        with indent_log():
            if self.require_hashes:
                raise InstallationError(
                    'The editable requirement {} cannot be installed when '
                    'requiring hashes, because there is no single file to '
                    'hash.'.format(req)
                )
            req.ensure_has_source_dir(self.src_dir)
            req.update_editable(not self._download_should_save)

            abstract_dist = _get_prepared_distribution(
                req, self.req_tracker, self.finder, self.build_isolation,
            )

            if self._download_should_save:
                req.archive(self.download_dir)
            req.check_if_exists(self.use_user_site)

        return abstract_dist

    def prepare_installed_requirement(
        self,
        req,  # type: InstallRequirement
        skip_reason  # type: str
    ):
        # type: (...) -> AbstractDistribution
        """Prepare an already-installed requirement
        """
        assert req.satisfied_by, "req should have been satisfied but isn't"
        assert skip_reason is not None, (
            "did not get skip reason skipped but req.satisfied_by "
            "is set to {}".format(req.satisfied_by)
        )
        logger.info(
            'Requirement %s: %s (%s)',
            skip_reason, req, req.satisfied_by.version
        )
        with indent_log():
            if self.require_hashes:
                logger.debug(
                    'Since it is already installed, we are trusting this '
                    'package without checking its hash. To ensure a '
                    'completely repeatable environment, install into an '
                    'empty virtualenv.'
                )
            abstract_dist = InstalledDistribution(req)

        return abstract_dist