deb-python-ceilometerclient/ceilometerclient/common/utils.py

# Copyright 2012 OpenStack Foundation
# All Rights Reserved.
#
#    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 print_function

import os
import textwrap

from oslo_serialization import jsonutils
from oslo_utils import encodeutils
import prettytable
import six

from ceilometerclient import exc


# Decorator for cli-args
def arg(*args, **kwargs):
    def _decorator(func):
        if 'help' in kwargs:
            if 'default' in kwargs:
                kwargs['help'] += " Defaults to %s." % kwargs['default']
            required = kwargs.get('required', False)
            if required:
                kwargs['help'] += " Required."

        # Because of the sematics of decorator composition if we just append
        # to the options list positional options will appear to be backwards.
        func.__dict__.setdefault('arguments', []).insert(0, (args, kwargs))
        return func
    return _decorator


def print_list(objs, fields, field_labels, formatters=None, sortby=0):
    """Print a list of objects as a table, one row per object.

    :param objs: Iterable of :class:`Resource`
    :param fields: Attributes that correspond to columns, in order
    :param field_labels: Labels to use in the heading of the table, default to
                         fields.
    :param formatters: `dict` of callables for field formatting
    :param sortby: Index of the field for sorting table rows
    """
    formatters = formatters or {}

    if len(field_labels) != len(fields):
        raise ValueError(("Field labels list %(labels)s has different number "
                          "of elements than fields list %(fields)s"),
                         {'labels': field_labels, 'fields': fields})

    def _make_default_formatter(field):
        return lambda o: getattr(o, field, '')

    new_formatters = {}
    for field, field_label in six.moves.zip(fields, field_labels):
        if field in formatters:
            new_formatters[field_label] = formatters[field]
        else:
            new_formatters[field_label] = _make_default_formatter(field)

    kwargs = {} if sortby is None else {'sortby': field_labels[sortby]}
    pt = prettytable.PrettyTable(field_labels)
    pt.align = 'l'

    for o in objs:
        row = []
        for field in field_labels:
            if field in new_formatters:
                row.append(new_formatters[field](o))
            else:
                field_name = field.lower().replace(' ', '_')
                data = getattr(o, field_name, '')
                row.append(data)
        pt.add_row(row)

    if six.PY3:
        print(encodeutils.safe_encode(pt.get_string(**kwargs)).decode())
    else:
        print(encodeutils.safe_encode(pt.get_string(**kwargs)))


def nested_list_of_dict_formatter(field, column_names):
    # (TMaddox) Because the formatting scheme actually drops the whole object
    # into the formatter, rather than just the specified field, we have to
    # extract it and then pass the value.
    return lambda o: format_nested_list_of_dict(getattr(o, field),
                                                column_names)


def format_nested_list_of_dict(l, column_names):
    pt = prettytable.PrettyTable(caching=False, print_empty=False,
                                 header=True, hrules=prettytable.FRAME,
                                 field_names=column_names)
    # Sort by values of first column
    if l is not None:
        l.sort(key=lambda k: k.get(column_names[0]))
    for d in l:
        pt.add_row(list(map(lambda k: d[k], column_names)))
    return pt.get_string()


def print_dict(d, dict_property="Property", wrap=0):
    pt = prettytable.PrettyTable([dict_property, 'Value'], print_empty=False)
    pt.align = 'l'
    for k, v in sorted(six.iteritems(d)):
        # convert dict to str to check length
        if isinstance(v, (list, dict)):
            v = jsonutils.dumps(v)
        # if value has a newline, add in multiple rows
        # e.g. fault with stacktrace
        if v and isinstance(v, six.string_types) and r'\n' in v:
            lines = v.strip().split(r'\n')
            col1 = k
            for line in lines:
                if wrap > 0:
                    line = textwrap.fill(six.text_type(line), wrap)
                pt.add_row([col1, line])
                col1 = ''
        else:
            if wrap > 0:
                v = textwrap.fill(six.text_type(v), wrap)
            pt.add_row([k, v])
    encoded = encodeutils.safe_encode(pt.get_string())
    # FIXME(gordc): https://bugs.launchpad.net/oslo-incubator/+bug/1370710
    if six.PY3:
        encoded = encoded.decode()
    print(encoded)


def args_array_to_dict(kwargs, key_to_convert):
    values_to_convert = kwargs.get(key_to_convert)
    if values_to_convert:
        try:
            kwargs[key_to_convert] = dict(v.split("=", 1)
                                          for v in values_to_convert)
        except ValueError:
            raise exc.CommandError(
                '%s must be a list of key=value not "%s"' % (
                    key_to_convert, values_to_convert))
    return kwargs


def args_array_to_list_of_dicts(kwargs, key_to_convert):
    """Converts ['a=1;b=2','c=3;d=4'] to [{a:1,b:2},{c:3,d:4}]."""
    values_to_convert = kwargs.get(key_to_convert)
    if values_to_convert:
        try:
            kwargs[key_to_convert] = []
            for lst in values_to_convert:
                pairs = lst.split(";")
                dct = dict()
                for pair in pairs:
                    kv = pair.split("=", 1)
                    dct[kv[0]] = kv[1].strip(" \"'")  # strip spaces and quotes
                kwargs[key_to_convert].append(dct)
        except Exception:
            raise exc.CommandError(
                '%s must be a list of key1=value1;key2=value2;... not "%s"' % (
                    key_to_convert, values_to_convert))
    return kwargs


def key_with_slash_to_nested_dict(kwargs):
    nested_kwargs = {}
    for k in list(kwargs):
        keys = k.split('/', 1)
        if len(keys) == 2:
            nested_kwargs.setdefault(keys[0], {})[keys[1]] = kwargs[k]
            del kwargs[k]
    kwargs.update(nested_kwargs)
    return kwargs


def merge_nested_dict(dest, source, depth=0):
    for (key, value) in six.iteritems(source):
        if isinstance(value, dict) and depth:
            merge_nested_dict(dest[key], value,
                              depth=(depth - 1))
        else:
            dest[key] = value


def env(*args, **kwargs):
    """Returns the first environment variable set.

    If all are empty, defaults to '' or keyword arg `default`.
    """
    for arg in args:
        value = os.environ.get(arg)
        if value:
            return value
    return kwargs.get('default', '')