fm-orchestrator/module_build_service/scm.py

# -*- coding: utf-8 -*-


# Copyright (c) 2016  Red Hat, Inc.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
#
# Modified by:
# Written by Karsten Hopp <karsten@redhat.com>
#            Petr Šabata <contyk@redhat.com>

"""SCM handler functions."""

from six.moves import http_client

import os
import subprocess as sp
import re
import tempfile
import shutil
import datetime

from module_build_service import log
from module_build_service.errors import Unauthorized, ValidationError
import module_build_service.utils


class SCM(object):
    "SCM abstraction class"

    # Assuming git for HTTP schemas
    types = module_build_service.utils.scm_url_schemes()

    def __init__(self, url, allowed_scm=None, allow_local = False):
        """Initialize the SCM object using the specified scmurl.

        If url is not in the list of allowed_scm, an error will be raised.

        :param str url: The unmodified scmurl
        :param list allowed_scm: The list of allowed SCMs, optional
        :raises: Unauthorized or ValidationError
        """

        if allowed_scm:
            if not (url.startswith(tuple(allowed_scm)) or
                    (allow_local and url.startswith("file://"))):
                raise Unauthorized(
                    '%s is not in the list of allowed SCMs' % url)

        self.url = url

        # once we have more than one SCM provider, we will need some more
        # sophisticated lookup logic
        for scmtype, schemes in SCM.types.items():
            if self.url.startswith(schemes):
                self.scheme = scmtype
                break
        else:
            raise ValidationError('Invalid SCM URL: %s' % url)

        # git is the only one supported SCM provider atm
        if self.scheme == "git":
            match = re.search(r"^(?P<repository>.*/(?P<name>[^?]*))(\?#(?P<commit>.*))?", url)
            self.repository = match.group("repository")
            self.name = match.group("name")
            self.repository_root = self.repository[:-len(self.name)]
            if self.name.endswith(".git"):
                self.name = self.name[:-4]
            self.commit = match.group("commit")
            self.branch = "master"
            self.version = None
        else:
            raise ValidationError("Unhandled SCM scheme: %s" % self.scheme)

    def scm_url_from_name(self, name):
        """
        Generates new SCM URL for another module defined by a name. The new URL
        is based on the root of current SCM URL.
        """
        if self.scheme == "git":
            return self.repository_root + name + ".git"

        return None

    @staticmethod
    @module_build_service.utils.retry(wait_on=RuntimeError)
    def _run(cmd, chdir=None, log_stdout = False):
        proc = sp.Popen(cmd, stdout=sp.PIPE, stderr=sp.PIPE, cwd=chdir)
        stdout, stderr = proc.communicate()
        if log_stdout and stdout:
            log.debug(stdout)
        if stderr:
            log.warning(stderr)
        if proc.returncode != 0:
            raise RuntimeError("Failed on %r, retcode %r, out %r, err %r" % (
                cmd, proc.returncode, stdout, stderr))
        return proc.returncode, stdout, stderr

    def checkout(self, scmdir):
        """Checkout the module from SCM.

        :param str scmdir: The working directory
        :returns: str -- the directory that the module was checked-out into
        :raises: RuntimeError
        """
        # TODO: sanity check arguments
        if self.scheme == "git":
            sourcedir = '%s/%s' % (scmdir, self.name)

            module_clone_cmd = ['git', 'clone', '-q']
            if self.commit:
                module_checkout_cmd = ['git', 'checkout', '-q', self.commit]
            else:
                module_clone_cmd.extend(['--depth', '1'])
            module_clone_cmd.extend([self.repository, sourcedir])

            # perform checkouts
            SCM._run(module_clone_cmd, chdir=scmdir)
            if self.commit:
                SCM._run(module_checkout_cmd, chdir=sourcedir)

            timestamp = SCM._run(["git", "show" , "-s", "--format=%ct"], chdir=sourcedir)[1]
            dt = datetime.datetime.utcfromtimestamp(int(timestamp))
            self.version = dt.strftime("%Y%m%d%H%M%S")
        else:
            raise RuntimeError("checkout: Unhandled SCM scheme.")
        return sourcedir

    def get_latest(self, branch='master'):
        """Get the latest commit ID.

        :returns: str -- the latest commit ID, e.g. the git $BRANCH HEAD
        :raises: RuntimeError
        """
        if self.scheme == "git":
            log.debug("Getting/verifying commit hash for %s" % self.repository)
            output = SCM._run(["git", "ls-remote", self.repository])[1]
            for line in output.split(os.linesep):
                if line.endswith("\trefs/heads/%s" % branch):
                    return line.split("\t")[0]

            # Hopefully `branch` is really a commit hash.  Code later needs to verify this.
            if self.is_available(True):
                return branch
            return branch
        else:
            raise RuntimeError("get_latest: Unhandled SCM scheme.")

    def is_available(self, strict=False):
        """Check whether the scmurl is available for checkout.

        :param bool strict: When True, raise expection on error instead of
                            returning False.
        :returns: bool -- the scmurl is available for checkout
        """
        td = None
        try:
            td = tempfile.mkdtemp()
            self.checkout(td)
            return True
        except:
            if strict:
                raise
            return False
        finally:
            try:
                if td is not None:
                    shutil.rmtree(td)
            except Exception as e:
                log.warning(
                    "Failed to remove temporary directory {!r}: {}".format(
                        td, str(e)))

    @property
    def url(self):
        """The original scmurl."""
        return self._url

    @url.setter
    def url(self, s):
        self._url = str(s)

    @property
    def scheme(self):
        """The SCM scheme."""
        return self._scheme

    @scheme.setter
    def scheme(self, s):
        self._scheme = str(s)

    @property
    def repository(self):
        """The repository part of the scmurl."""
        return self._repository

    @repository.setter
    def repository(self, s):
        self._repository = str(s)

    @property
    def commit(self):
        """The commit ID, for example the git hash, or None."""
        return self._commit

    @commit.setter
    def commit(self, s):
        self._commit = str(s) if s else None

    @property
    def name(self):
        """The module name."""
        return self._name

    @name.setter
    def name(self, s):
        self._name = str(s)