Python pkg_resources 模块，ResolutionError() 实例源码

def pkg_info(project_name=None, include_extras=False):
    if project_name is None:
        project_name = PROJECT_NAME
    try:
        distribution = pkg_resources.get_distribution(project_name)
        extras = include_extras and distribution.extras or []
        dependencies = [
            pkg_info(d) for d in distribution.requires(extras)]
        return {
            'name': project_name,
            'version': distribution.version,
            'path': distribution.location,
            'dependencies': dependencies,
        }
    except pkg_resources.ResolutionError:
        return {
            'name': project_name,
        }

def _runscript(scriptname):
    """
    Find & run a script with exec (i.e. not via os.system or subprocess).
    """

    import pkg_resources
    ns = {"__name__": "__main__"}
    ns['sys'] = globals()['sys']

    try:
        pkg_resources.get_distribution("shmlast").run_script(scriptname, ns)
        return 0
    except pkg_resources.ResolutionError as err:
        path = scriptpath()

        scriptfile = os.path.join(path, scriptname)
        if os.path.isfile(scriptfile):
            if os.path.isfile(scriptfile):
                exec(compile(open(scriptfile).read(), scriptfile, 'exec'), ns)
                return 0

    return -1

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None

def with_requires(*requirements):
    """Run a test case only when given requirements are satisfied.

    .. admonition:: Example

       This test case runs only when `numpy>=1.10` is installed.

       >>> from cupy import testing
       ... class Test(unittest.TestCase):
       ...     @testing.with_requires('numpy>=1.10')
       ...     def test_for_numpy_1_10(self):
       ...         pass

    Args:
        requirements: A list of string representing requirement condition to
            run a given test case.

    """
    ws = pkg_resources.WorkingSet()
    try:
        ws.require(*requirements)
        skip = False
    except pkg_resources.ResolutionError:
        skip = True

    msg = 'requires: {}'.format(','.join(requirements))
    return unittest.skipIf(skip, msg)

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None

def is_installed(requirement):
    try:
        pkg_resources.require(requirement)
    except pkg_resources.ResolutionError:
        return False
    else:
        return True

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def load_consensus_plugin(name=None):
    """Find and load the chosen consensus plugin.

    Args:
        name (string): the name of the entry_point, as advertised in the
            setup.py of the providing package.

    Returns:
        an uninstantiated subclass of ``bigchaindb.consensus.AbstractConsensusRules``
    """
    if not name:
        return BaseConsensusRules

    # TODO: This will return the first plugin with group `bigchaindb.consensus`
    #       and name `name` in the active WorkingSet.
    #       We should probably support Requirements specs in the config, e.g.
    #       consensus_plugin: 'my-plugin-package==0.0.1;default'
    plugin = None
    for entry_point in iter_entry_points('bigchaindb.consensus', name):
        plugin = entry_point.load()

    # No matching entry_point found
    if not plugin:
        raise ResolutionError(
            'No plugin found in group `bigchaindb.consensus` with name `{}`'.
            format(name))

    # Is this strictness desireable?
    # It will probably reduce developer headaches in the wild.
    if not issubclass(plugin, (BaseConsensusRules,)):
        raise TypeError('object of type "{}" does not implement `bigchaindb.'
                        'consensus.BaseConsensusRules`'.format(type(plugin)))

    return plugin

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name=='nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        return pkg_resources.resource_filename('certifi', 'cacert.pem')
    except (ImportError, ResolutionError, ExtractionError):
        return None

def _certifi_where():
    try:
        return __import__('certifi').where()
    except (ImportError, ResolutionError, ExtractionError):
        pass

def find_ca_bundle():
    """Return an existing CA bundle path, or None"""
    if os.name == 'nt':
        return get_win_certfile()
    else:
        for cert_path in cert_paths:
            if os.path.isfile(cert_path):
                return cert_path
    try:
        import certifi
        return certifi.where()
    except (ImportError, ResolutionError, ExtractionError):
        return None