swift/test/unit/__init__.py

""" Swift tests """

import sys
import os
import copy
import logging
from sys import exc_info
from contextlib import contextmanager
from collections import defaultdict
from tempfile import NamedTemporaryFile
from eventlet.green import socket
from tempfile import mkdtemp
from shutil import rmtree
from test import get_config
from ConfigParser import MissingSectionHeaderError
from StringIO import StringIO
from swift.common.utils import readconf, config_true_value
from logging import Handler
import logging.handlers


def readuntil2crlfs(fd):
    rv = ''
    lc = ''
    crlfs = 0
    while crlfs < 2:
        c = fd.read(1)
        rv = rv + c
        if c == '\r' and lc != '\n':
            crlfs = 0
        if lc == '\r' and c == '\n':
            crlfs += 1
        lc = c
    return rv


def connect_tcp(hostport):
    rv = socket.socket()
    rv.connect(hostport)
    return rv


@contextmanager
def tmpfile(content):
    with NamedTemporaryFile('w', delete=False) as f:
        file_name = f.name
        f.write(str(content))
    try:
        yield file_name
    finally:
        os.unlink(file_name)

xattr_data = {}


def _get_inode(fd):
    if not isinstance(fd, int):
        try:
            fd = fd.fileno()
        except AttributeError:
            return os.stat(fd).st_ino
    return os.fstat(fd).st_ino


def _setxattr(fd, k, v):
    inode = _get_inode(fd)
    data = xattr_data.get(inode, {})
    data[k] = v
    xattr_data[inode] = data


def _getxattr(fd, k):
    inode = _get_inode(fd)
    data = xattr_data.get(inode, {}).get(k)
    if not data:
        raise IOError
    return data

import xattr
xattr.setxattr = _setxattr
xattr.getxattr = _getxattr


@contextmanager
def temptree(files, contents=''):
    # generate enough contents to fill the files
    c = len(files)
    contents = (list(contents) + [''] * c)[:c]
    tempdir = mkdtemp()
    for path, content in zip(files, contents):
        if os.path.isabs(path):
            path = '.' + path
        new_path = os.path.join(tempdir, path)
        subdir = os.path.dirname(new_path)
        if not os.path.exists(subdir):
            os.makedirs(subdir)
        with open(new_path, 'w') as f:
            f.write(str(content))
    try:
        yield tempdir
    finally:
        rmtree(tempdir)


class NullLoggingHandler(logging.Handler):

    def emit(self, record):
        pass


class FakeLogger(object):
    # a thread safe logger

    def __init__(self, *args, **kwargs):
        self._clear()
        self.level = logging.NOTSET
        if 'facility' in kwargs:
            self.facility = kwargs['facility']

    def _clear(self):
        self.log_dict = defaultdict(list)

    def _store_in(store_name):
        def stub_fn(self, *args, **kwargs):
            self.log_dict[store_name].append((args, kwargs))
        return stub_fn

    error = _store_in('error')
    info = _store_in('info')
    warning = _store_in('warning')
    debug = _store_in('debug')

    def exception(self, *args, **kwargs):
        self.log_dict['exception'].append((args, kwargs, str(exc_info()[1])))

    # mock out the StatsD logging methods:
    increment = _store_in('increment')
    decrement = _store_in('decrement')
    timing = _store_in('timing')
    timing_since = _store_in('timing_since')
    update_stats = _store_in('update_stats')
    set_statsd_prefix = _store_in('set_statsd_prefix')

    def get_increments(self):
        return [call[0][0] for call in self.log_dict['increment']]

    def get_increment_counts(self):
        counts = {}
        for metric in self.get_increments():
            if metric not in counts:
                counts[metric] = 0
            counts[metric] += 1
        return counts

    def setFormatter(self, obj):
        self.formatter = obj

    def close(self):
        self._clear()

    def set_name(self, name):
        # don't touch _handlers
        self._name = name

    def acquire(self):
        pass

    def release(self):
        pass

    def createLock(self):
        pass

    def emit(self, record):
        pass

    def handle(self, record):
        pass

    def flush(self):
        pass

    def handleError(self, record):
        pass


original_syslog_handler = logging.handlers.SysLogHandler


def fake_syslog_handler():
    for attr in dir(original_syslog_handler):
        if attr.startswith('LOG'):
            setattr(FakeLogger, attr,
                    copy.copy(getattr(logging.handlers.SysLogHandler, attr)))
    FakeLogger.priority_map = \
        copy.deepcopy(logging.handlers.SysLogHandler.priority_map)

    logging.handlers.SysLogHandler = FakeLogger


if config_true_value(get_config('unit_test').get('fake_syslog', 'False')):
    fake_syslog_handler()


class MockTrue(object):
    """
    Instances of MockTrue evaluate like True
    Any attr accessed on an instance of MockTrue will return a MockTrue
    instance. Any method called on an instance of MockTrue will return
    a MockTrue instance.

    >>> thing = MockTrue()
    >>> thing
    True
    >>> thing == True # True == True
    True
    >>> thing == False # True == False
    False
    >>> thing != True # True != True
    False
    >>> thing != False # True != False
    True
    >>> thing.attribute
    True
    >>> thing.method()
    True
    >>> thing.attribute.method()
    True
    >>> thing.method().attribute
    True

    """

    def __getattribute__(self, *args, **kwargs):
        return self

    def __call__(self, *args, **kwargs):
        return self

    def __repr__(*args, **kwargs):
        return repr(True)

    def __eq__(self, other):
        return other is True

    def __ne__(self, other):
        return other is not True


@contextmanager
def mock(update):
    returns = []
    deletes = []
    for key, value in update.items():
        imports = key.split('.')
        attr = imports.pop(-1)
        module = __import__(imports[0], fromlist=imports[1:])
        for modname in imports[1:]:
            module = getattr(module, modname)
        if hasattr(module, attr):
            returns.append((module, attr, getattr(module, attr)))
        else:
            deletes.append((module, attr))
        setattr(module, attr, value)
    yield True
    for module, attr, value in returns:
        setattr(module, attr, value)
    for module, attr in deletes:
        delattr(module, attr)