Support for local mode in cros_interface.

Most methods of CrosInterface can now be called locally on a cros device.
* Allow CrosInterface to be initialized without a hostname. 
* Add property local to CrosInterface.
* Add unit tests for 2 public methods of CrosInterface FileExistsOnDevice and IsServiceRunning.

BUG=178278
TEST=run_tests textExistsLocal and testIsServiceRunningLocal on cros_device/linux desktop.
NOTRY=true
Review URL: https://codereview.chromium.org/12667002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@187808 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 36 insertions, 4 deletions

diff --git a/tools/telemetry/telemetry/core/chrome/cros_interface.py b/tools/telemetry/telemetry/core/chrome/cros_interface.py
index a7ce360..2e2d087 100644
--- a/tools/telemetry/telemetry/core/chrome/cros_interface.py
+++ b/tools/telemetry/telemetry/core/chrome/cros_interface.py
@@ -200,8 +200,14 @@ class KeylessLoginRequiredException(LoginException):
 
 class CrOSInterface(object):
   # pylint: disable=R0923
-  def __init__(self, hostname, ssh_identity = None):
+  def __init__(self, hostname = None, ssh_identity = None):
     self._hostname = hostname
+    # List of ports generated from GetRemotePort() that may not be in use yet.
+    self._reserved_ports = []
+
+    if self.local:
+      return
+
     self._ssh_identity = None
     self._hostfile = tempfile.NamedTemporaryFile()
     self._hostfile.flush()
@@ -211,17 +217,21 @@ class CrOSInterface(object):
                       '-o PreferredAuthentications=publickey',
                       '-o UserKnownHostsFile=%s' % self._hostfile.name]
 
-    # List of ports generated from GetRemotePort() that may not be in use yet.
-    self._reserved_ports = []
-
     if ssh_identity:
       self._ssh_identity = os.path.abspath(os.path.expanduser(ssh_identity))
 
   @property
+  def local(self):
+    return not self._hostname
+
+  @property
   def hostname(self):
     return self._hostname
 
   def FormSSHCommandLine(self, args, extra_ssh_args=None):
+    if self.local:
+      return args
+
     full_args = ['ssh',
                  '-o ForwardX11=no',
                  '-o ForwardX11Trusted=no',
@@ -257,6 +267,7 @@ class CrOSInterface(object):
 
   def TryLogin(self):
     logging.debug('TryLogin()')
+    assert not self.local
     stdout, stderr = self.RunCmdOnDevice(['echo', '$USER'], quiet=True)
     if stderr != '':
       if 'Host key verification failed' in stderr:
@@ -280,6 +291,9 @@ class CrOSInterface(object):
           self._hostname, stdout))
 
   def FileExistsOnDevice(self, file_name, quiet=False):
+    if self.local:
+      return os.path.exists(file_name)
+
     stdout, stderr = self.RunCmdOnDevice([
         'if', 'test', '-a', file_name, ';',
         'then', 'echo', '1', ';',
@@ -297,6 +311,7 @@ class CrOSInterface(object):
     return exists
 
   def PushFile(self, filename, remote_filename):
+    assert not self.local
     args = ['scp', '-r' ] + self._ssh_args
     if self._ssh_identity:
       args.extend(['-i', self._ssh_identity])
@@ -317,6 +332,7 @@ class CrOSInterface(object):
       self.PushFile(f.name, remote_filename)
 
   def GetFileContents(self, filename):
+    assert not self.local
     with tempfile.NamedTemporaryFile() as f:
       args = ['scp'] + self._ssh_args
       if self._ssh_identity:
diff --git a/tools/telemetry/telemetry/core/chrome/cros_interface_unittest.py b/tools/telemetry/telemetry/core/chrome/cros_interface_unittest.py
index a97cbb8..3e7c612 100644
--- a/tools/telemetry/telemetry/core/chrome/cros_interface_unittest.py
+++ b/tools/telemetry/telemetry/core/chrome/cros_interface_unittest.py
@@ -7,6 +7,7 @@
 # a bit.
 import unittest
 import socket
+import sys
 
 from telemetry.core import util
 from telemetry.core.chrome import cros_browser_backend
@@ -69,6 +70,15 @@ class CrOSInterfaceTest(unittest.TestCase):
     self.assertTrue(cri.FileExistsOnDevice('/etc/passwd'))
     self.assertFalse(cri.FileExistsOnDevice('/etc/sdlfsdjflskfjsflj'))
 
+  def testExistsLocal(self):
+    if not sys.platform.startswith('linux'):
+      return
+
+    cri = cros_interface.CrOSInterface()
+    self.assertTrue(cri.FileExistsOnDevice('/proc/cpuinfo'))
+    self.assertTrue(cri.FileExistsOnDevice('/etc/passwd'))
+    self.assertFalse(cri.FileExistsOnDevice('/etc/sdlfsdjflskfjsflj'))
+
   @run_tests.RequiresBrowserOfType('cros-chrome')
   def testGetFileContents(self): # pylint: disable=R0201
     remote = options_for_unittests.GetCopy().cros_remote
@@ -112,6 +122,12 @@ class CrOSInterfaceTest(unittest.TestCase):
 
     self.assertTrue(cri.IsServiceRunning('openssh-server'))
 
+  def testIsServiceRunningLocal(self):
+    if not sys.platform.startswith('linux'):
+      return
+    cri = cros_interface.CrOSInterface()
+    self.assertTrue(cri.IsServiceRunning('dbus'))
+
   @run_tests.RequiresBrowserOfType('cros-chrome')
   def testGetRemotePortAndIsHTTPServerRunningOnPort(self):
     remote = options_for_unittests.GetCopy().cros_remote