~azzar1/unity/add-show-desktop-key

# IVLE - Informatics Virtual Learning Environment

# Copyright (C) 2007-2010 The University of Melbourne

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

import socket

import os

import random

import cjson

from nose.tools import assert_equal, raises

import ivle.chat

TIMEOUT = 0.1

NULLNETSTRING = "0:,"

SIMPLESTRING = "Hello world!"

SIMPLENETSTRING = "12:Hello world!,"

class TestChat(object):

    def setUp(self):

        """Creates a socket pair for testing"""

        self.s1, self.s2 = socket.socketpair()

        self.s1.settimeout(TIMEOUT)

        self.s2.settimeout(TIMEOUT)

    def tearDown(self):

        """Closes the socket pair"""

        self.s1.close()

        self.s2.close()

    def test_send_null_netstring(self):

        """Check that we construct a empty Netstring correctly"""

        ivle.chat.send_netstring(self.s1, "")

        assert_equal(self.s2.recv(1024), NULLNETSTRING)

    def test_send_simple_netstring(self):

        """Check that we construct a simple Netstring correctly"""

        ivle.chat.send_netstring(self.s1, SIMPLESTRING)

        assert_equal(self.s2.recv(1024), SIMPLENETSTRING)

    def test_recv_null_netstring(self):

        """Check that we can decode a null Netstring"""

        self.s1.sendall(NULLNETSTRING)

        assert_equal(ivle.chat.recv_netstring(self.s2), "")

    def test_recv_null_netstring(self):

        """Check that we can decode a simple Netstring"""

        self.s1.sendall(SIMPLENETSTRING)

        assert_equal(ivle.chat.recv_netstring(self.s2), SIMPLESTRING)

    @raises(socket.timeout)

    def test_invalid_short_netstring(self):

        self.s1.sendall("1234:not that long!,")

        assert ivle.chat.recv_netstring(self.s2) is None

    @raises(ivle.chat.ProtocolError)

    def test_invalid_long_netstring(self):

        self.s1.sendall("5:not that short!,")

        assert ivle.chat.recv_netstring(self.s2) is None

    def test_long_netstring(self):

        # XXX: send() may block if this is too big

        msg = os.urandom(50000)

        ivle.chat.send_netstring(self.s1, msg)

        assert ivle.chat.recv_netstring(self.s2) == msg

    def test_multiple_netstrings(self):

        messages = []

        for i in range(10):

            message = os.urandom(random.randint(0,20))

            messages.append(message)

            ivle.chat.send_netstring(self.s1, message)

        for i in range(10):

            assert_equal(ivle.chat.recv_netstring(self.s2), messages[i])

    def test_encode(self):

        """Check that we correctly encode a basic object

        """

        MESSAGE = {}

        MAGIC = "3EE"

        content = cjson.encode(MESSAGE)

        # Digest can be formed with `echo -n "${content}${MAGIC}" | md5sum`

        DIGEST = '2b59b68e1ac0852b87fb7e64946f2658'

        expected = {'digest': DIGEST,

                'content': content}

        encoded = ivle.chat.encode(MESSAGE, MAGIC)

        assert_equal(cjson.decode(encoded), expected)

    def test_encode_decode(self):

        """Check that a round trip encoding and decoding works

        """

        MESSAGE = {'message': 'Hello, world'}

        MAGIC = "MagicString"

        encoded = ivle.chat.encode(MESSAGE, MAGIC)

        decoded = ivle.chat.decode(encoded, MAGIC)

        assert_equal(decoded, MESSAGE)

    @raises(ivle.chat.ProtocolError)

    def test_decode_bad_magic(self):

        """Check that a bad digest causes a ProtocolError to be raised

        """

        CHATMESSAGE = ('{"content": "{\\"a\\": \\"b\\"}", "digest": ' +

                '"eb860a5fe8fdbef19ffb79e3a5c47113"}')

        CORRECTMAGIC = "AEIOU"

        INCORRECTMAGIC = "ABCDE"

        # Check our "correct" string decodes without a ProtocolError

        try:

            ivle.chat.decode(CHATMESSAGE, CORRECTMAGIC)

        except ivle.chat.ProtocolError:

            raise AssertionError("ProtocolError with 'correct' magic")

        # This should raise the ProtocolError

        ivle.chat.decode(CHATMESSAGE, INCORRECTMAGIC)