lib/docker/docker/utils/utils.py

# Copyright 2013 dotCloud inc.

#    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.

import io
import tarfile
import tempfile
from distutils.version import StrictVersion

import requests
import six


def mkbuildcontext(dockerfile):
    f = tempfile.NamedTemporaryFile()
    t = tarfile.open(mode='w', fileobj=f)
    if isinstance(dockerfile, io.StringIO):
        dfinfo = tarfile.TarInfo('Dockerfile')
        if six.PY3:
            raise TypeError('Please use io.BytesIO to create in-memory '
                            'Dockerfiles with Python 3')
        else:
            dfinfo.size = len(dockerfile.getvalue())
    elif isinstance(dockerfile, io.BytesIO):
        dfinfo = tarfile.TarInfo('Dockerfile')
        dfinfo.size = len(dockerfile.getvalue())
    else:
        dfinfo = t.gettarinfo(fileobj=dockerfile, arcname='Dockerfile')
    t.addfile(dfinfo, dockerfile)
    t.close()
    f.seek(0)
    return f


def tar(path):
    f = tempfile.NamedTemporaryFile()
    t = tarfile.open(mode='w', fileobj=f)
    t.add(path, arcname='.')
    t.close()
    f.seek(0)
    return f


def compare_version(v1, v2):
    """Compare docker versions

    >>> v1 = '1.9'
    >>> v2 = '1.10'
    >>> compare_version(v1, v2)
    1
    >>> compare_version(v2, v1)
    -1
    >>> compare_version(v2, v2)
    0
    """
    s1 = StrictVersion(v1)
    s2 = StrictVersion(v2)
    if s1 == s2:
        return 0
    elif s1 > s2:
        return -1
    else:
        return 1


def ping(url):
    try:
        res = requests.get(url)
    except Exception:
        return False
    else:
        return res.status_code < 400


def _convert_port_binding(binding):
    result = {'HostIp': '', 'HostPort': ''}
    if isinstance(binding, tuple):
        if len(binding) == 2:
            result['HostPort'] = binding[1]
            result['HostIp'] = binding[0]
        elif isinstance(binding[0], six.string_types):
            result['HostIp'] = binding[0]
        else:
            result['HostPort'] = binding[0]
    else:
        result['HostPort'] = binding

    if result['HostPort'] is None:
        result['HostPort'] = ''
    else:
        result['HostPort'] = str(result['HostPort'])

    return result


def convert_port_bindings(port_bindings):
    result = {}
    for k, v in six.iteritems(port_bindings):
        key = str(k)
        if '/' not in key:
            key = key + '/tcp'
        if isinstance(v, list):
            result[key] = [_convert_port_binding(binding) for binding in v]
        else:
            result[key] = [_convert_port_binding(v)]
    return result


def parse_repository_tag(repo):
    column_index = repo.rfind(':')
    if column_index < 0:
        return repo, ""
    tag = repo[column_index+1:]
    slash_index = tag.find('/')
    if slash_index < 0:
        return repo[:column_index], tag

    return repo, ""