cli/cros/cros_shell_unittest.py

# Copyright 2015 The ChromiumOS Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Tests the `cros shell` command."""

import pytest  # pylint: disable=import-error

from chromite.cli import command_unittest
from chromite.cli.cros import cros_shell
from chromite.lib import cros_build_lib
from chromite.lib import cros_test_lib
from chromite.lib import remote_access


class _KeyMismatchError(remote_access.SSHConnectionError):
    """Test exception to fake a key mismatch."""

    def IsKnownHostsMismatch(self):
        return True


class MockShellCommand(command_unittest.MockCommand):
    """Mock out the `cros shell` command."""

    TARGET = "chromite.cli.cros.cros_shell.ShellCommand"
    TARGET_CLASS = cros_shell.ShellCommand
    COMMAND = "shell"


@pytest.mark.usefixtures("testcase_caplog")
class ShellTest(cros_test_lib.MockTempDirTestCase):
    """Test the flow of ShellCommand.run with the SSH methods mocked out."""

    DEVICE_IP = remote_access.TEST_IP

    def SetupCommandMock(self, cmd_args):
        """Sets up the `cros shell` command mock."""
        self.cmd_mock = MockShellCommand(
            cmd_args, base_args=["--cache-dir", str(self.tempdir)]
        )
        self.StartPatcher(self.cmd_mock)

    def setUp(self):
        """Patches objects."""
        self.cmd_mock = None

        # Patch any functions we want to control that may get called by a test.
        self.mock_remove_known_host = self.PatchObject(
            remote_access, "RemoveKnownHost", autospec=True
        )
        self.mock_prompt = self.PatchObject(
            cros_build_lib, "BooleanPrompt", autospec=True
        )

        self.mock_device = self.PatchObject(
            remote_access, "ChromiumOSDevice", autospec=True
        ).return_value
        self.mock_device.hostname = self.DEVICE_IP
        self.mock_device.connection_type = None
        self.mock_run_command = self.mock_device.run
        self.mock_run_command.return_value = cros_build_lib.CompletedProcess()

    def testSshInteractive(self):
        """Tests flow for an interactive session.

        User should not be prompted for input, and SSH should be attempted
        once.
        """
        self.SetupCommandMock([self.DEVICE_IP])
        self.cmd_mock.inst.Run()

        self.assertEqual(self.mock_run_command.call_count, 1)
        # Make sure that run() started an interactive session (no cmd).
        self.assertEqual(self.mock_run_command.call_args[0][0], [])
        self.assertFalse(self.mock_prompt.called)

    def testSshNonInteractiveSingleArg(self):
        """Tests a non-interactive command as a single argument.

        Examples:
            cros shell 127.0.0.1 "ls -l /etc"
        """
        self.SetupCommandMock([self.DEVICE_IP, "ls -l /etc"])
        self.cmd_mock.inst.Run()

        self.assertEqual(self.mock_run_command.call_args[0][0], ["ls -l /etc"])

    def testSshNonInteractiveMultipleArgs(self):
        """Tests a non-interactive command as multiple arguments with "--".

        Examples:
            cros shell 127.0.0.1 -- ls -l /etc
        """
        self.SetupCommandMock([self.DEVICE_IP, "--", "ls", "-l", "/etc"])
        self.cmd_mock.inst.Run()

        self.assertEqual(
            self.mock_run_command.call_args[0][0], ["ls", "-l", "/etc"]
        )

    def testSshReturnValue(self):
        """Tests that `cros shell` returns the exit code of run()."""
        self.SetupCommandMock([self.DEVICE_IP])
        self.mock_run_command.return_value.returncode = 42

        self.assertEqual(self.cmd_mock.inst.Run(), 42)

    def testSshKeyChangeOK(self):
        """Tests a host SSH key changing but the user giving it the OK.

        User should be prompted, SSH should be attempted twice, and host
        keys should be removed.
        """
        self.SetupCommandMock([self.DEVICE_IP])
        error_message = "Test error message"
        # run() gives a key mismatch error the first time only.
        self.mock_run_command.side_effect = [
            _KeyMismatchError(error_message),
            cros_build_lib.CompletedProcess(),
        ]
        # User chooses to continue.
        self.mock_prompt.return_value = True

        self.cmd_mock.inst.Run()

        self.assertIn(error_message, self.caplog.text)
        self.assertTrue(self.mock_prompt.called)
        self.assertEqual(self.mock_run_command.call_count, 2)
        self.assertTrue(self.mock_remove_known_host.called)

    def testSshKeyChangeAbort(self):
        """Tests a host SSH key changing and the user canceling.

        User should be prompted, but SSH should only be attempted once, and
        no host keys should be removed.
        """
        self.SetupCommandMock([self.DEVICE_IP])
        self.mock_run_command.side_effect = _KeyMismatchError()
        # User chooses to abort.
        self.mock_prompt.return_value = False

        self.cmd_mock.inst.Run()

        self.assertTrue(self.mock_prompt.called)
        self.assertEqual(self.mock_run_command.call_count, 1)
        self.assertFalse(self.mock_remove_known_host.called)

    def testSshConnectError(self):
        """Tests an SSH error other than a host key mismatch.

        User should not be prompted, SSH should only be attempted once, and
        no host keys should be removed.
        """
        self.SetupCommandMock([self.DEVICE_IP])
        self.mock_run_command.side_effect = remote_access.SSHConnectionError()

        self.assertEqual(self.cmd_mock.inst.Run(), 1)

        self.assertFalse(self.mock_prompt.called)
        self.assertEqual(self.mock_run_command.call_count, 1)
        self.assertFalse(self.mock_remove_known_host.called)