dist_utils.py

# -*- coding: utf-8 -*-
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from __future__ import absolute_import

import os
import re
import sys

from distutils import version

GET_PIP = 'curl https://bootstrap.pypa.io/get-pip.py | python'

try:
    import pip
except ImportError as e:
    print('Failed to import pip: %s' % (str(e)))
    print('')
    print('Download pip:\n%s' % (GET_PIP))
    sys.exit(1)

__all__ = [
    'check_pip_version',
    'fetch_requirements',
    'apply_vagrant_workaround',
    'get_version_string',
    'parse_version_string'
]


def check_pip_version(min_version='6.0.0'):
    """Ensure that a minimum supported version of pip is installed.

    """
    if version.StrictVersion(pip.__version__) < version.StrictVersion(min_version):
        print("Upgrade pip, your version '{0}' "
              "is outdated. Minimum required version is '{1}':\n{2}".format(pip.__version__,
                                                                            min_version,
                                                                            GET_PIP))
        sys.exit(1)


def fetch_requirements(requirements_file_path):
    """Return a list of requirements and links by parsing the provided requirements file.

    """
    links = []
    reqs = []

    def _get_link(line):
        vcs_prefixes = ['git+', 'svn+', 'hg+', 'bzr+']

        for vcs_prefix in vcs_prefixes:
            if line.startswith(vcs_prefix) or line.startswith('-e %s' % (vcs_prefix)):
                req_name = re.findall('.*#egg=(.+)([&|@]).*$', line)

                if not req_name:
                    req_name = re.findall('.*#egg=(.+?)$', line)
                else:
                    req_name = req_name[0]

                if not req_name:
                    raise ValueError('Line "%s" is missing "#egg=<package name>"' % (line))

                link = line.replace('-e ', '').strip()
                return link, req_name[0]

        return None, None

    with open(requirements_file_path, 'r') as fp:
        for line in fp.readlines():
            line = line.strip()

            if line.startswith('#') or not line:
                continue

            link, req_name = _get_link(line=line)

            if link:
                links.append(link)
            else:
                req_name = line

                if ';' in req_name:
                    req_name = req_name.split(';')[0].strip()

            reqs.append(req_name)

    return (reqs, links)


def apply_vagrant_workaround():
    """Function which detects if the script is being executed inside vagrant

    Function which detects if the script is being executed inside vagrant and if it is, it deletes
    "os.link" attribute.
    Note: Without this workaround, setup.py sdist will fail when running inside a shared directory
    (nfs / virtualbox shared folders).
    """
    if os.environ.get('USER', None) == 'vagrant':
        del os.link


def get_version_string(init_file):
    """Read __version__ string for an init file.

    """

    with open(init_file, 'r') as fp:
        content = fp.read()
        version_match = re.search(r"^__version__ = ['\"]([^'\"]*)['\"]",
                                  content, re.M)
        if version_match:
            return version_match.group(1)

        raise RuntimeError('Unable to find version string in %s.' % (init_file))


# alias for get_version_string
parse_version_string = get_version_string