Adding PyAuto Battery test for ChromeOS

chrome/test/functional/chromeos_battery.py

+#!/usr/bin/python
+# Copyright (c) 2011 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that
+# can be found in the LICENSE file.
+
+import logging

[dtu, 2011/05/27 23:33:43]

Unused import. Remove.

[scottc, 2011/05/31 15:40:21]

Done.

+import os
+import time
+
+import pyauto_functional

[dtu, 2011/05/27 23:33:43]

Please say this:
import pyauto_functional  # Must be imported before pyauto

[scottc, 2011/05/31 15:40:21]

Done.

+import pyauto
+
+from chromeos.power_strip import PowerStrip
+
+class ChromeosBattery(pyauto.PyUITest):
+  """Tests ChromeOS Battery Status API.
+  Preconditions:
+     1) Device under test (DUT) is connected to the corporate LAN
+     LAN via Ethernet-to-USB adapter plugged into one of its
+     USB ports.
+     2) AC power cable is connected to the DUT, and plugged into
+     the IP controlled Power Switch, outlet #4, located in the
+     Oyster Bay lab.
+     3) Battery is installed in the DUT, and battery is not fully
+     discharged.
+
+  Battery Info is a dictionary with keys:

[dtu, 2011/05/27 23:33:43]

You don't need to include the entire dictionary in a comment here, it's already
in the GetBatteryInfo() doc.

[scottc, 2011/05/31 15:40:21]

Removed.

+    'battery_is_present': bool
+    'line_power_on': bool
+    if 'battery_is_present':
+      'battery_percentage': float (0 ~ 100)
+      'battery_fully_charged': bool
+      if 'line_power_on':
+        'battery_time_to_full': int (seconds)
+      else:
+        'battery_time_to_empty': int (seconds)
+
+    When AC power is turn off or on, the battery will take from 2
+    to 60 seconds to calculate the time left. While calculating, the
+    keys 'battery_time_to_full' and 'battery_time_to_empty' are
+    absent.
+  """
+
+  _OUTLET_WITH_BATTERY = '.a4'
+  _BATTERY_CONFIG_FILE = os.path.join(pyauto.PyUITest.DataDir(),
+                                     'pyauto_private', 'chromeos', 'power',
+                                     'battery_testbed_config')
+
+  def setUp(self):
+    pyauto.PyUITest.setUp(self)
+    self.InitPowerStrip()
+
+

[dtu, 2011/05/27 23:33:43]

One blank line between function definitions inside a class.

[scottc, 2011/05/31 15:40:21]

Done.

+  def tearDown(self):
+    # Leave power outlet On so battery does not discharge
+    self._power_strip.PowerOn(ChromeosBattery._OUTLET_WITH_BATTERY)
+    pyauto.PyUITest.tearDown(self)
+
+
+  def InitPowerStrip(self):
+    self.assertTrue(
+        lambda: os.path.exists(ChromeosBattery._BATTERY_CONFIG_FILE),
+        msg = 'Power Strip configuration file does not exist.')
+    power_config = /
+        pyauto.PyUITest.EvalDataFrom(ChromeosBattery._BATTERY_CONFIG_FILE)
+    self._power_strip = PowerStrip(power_config['strip_ip'])
+
+
+  def WaitUntilBatteryTimeIsCalculated(self):
+    battery_status = self.GetBatteryInfo()
+    if battery_status.get('line_power_on'):
+      time_key = 'battery_time_to_full'
+    else:
+      time_key = 'battery_time_to_empty'
+    return self.WaitUntil(lambda: self.GetBatteryInfo().get(time_key) != None,
+                          timeout=60,
+                          retry_sleep=2)

[dtu, 2011/05/27 23:33:43]

Probably want to shorten the timeout and keep the default retry_sleep (which is
0.25s). 60 seconds is a long time for a test to hang.

[scottc, 2011/05/31 15:40:21]

During testing, I've seen it sometimes take up to 40 seconds for the
time_to_full and time_to_empty to calculate. Is there a stated requirement for
the longest it can take?  If so, we should use that as the timeout.  If not,
timeout should be high enough to eliminate false failures.

I see that power_BatteryCharge.py uses 60 seconds for the timeout
(http://git.chromium.org/gitweb/?p=chromiumos/third_party/autotest.git;a=blob;...).

[dtu, 2011/06/01 01:09:23]

Okay, in that case it is fine.

On 2011/05/31 15:40:21, scottc wrote:

+
+
+  def testBatteryChargesWhenACisOn(self):
+    """AC power ON to CrOS device with battery."""
+    self._power_strip.PowerOn(ChromeosBattery._OUTLET_WITH_BATTERY)
+    time.sleep(2) # Wait for swtich to settle

[dtu, 2011/05/27 23:33:43]

switch*

[scottc, 2011/05/31 15:40:21]

Removed.

+
+    # Get info about charging battery
+    self.assertTrue(self.WaitUntilBatteryTimeIsCalculated(),
+        msg='Battery charge time was not calculated')
+    battery_status = self.GetBatteryInfo()
+    self.assertTrue(battery_status.get('battery_is_present'),
+        msg='Battery is not present.')
+    self.assertTrue(battery_status.get('line_power_on'),
+        msg='Line power is off.')
+    self.assertTrue(battery_status.get('battery_time_to_full') >= 0,
+        msg='Battery charge time is negative.')
+
+
+  def testBatteryDischargesWhenACisOff(self):
+    """AC power OFF to CrOS device with battery."""
+    self._power_strip.PowerOff(ChromeosBattery._OUTLET_WITH_BATTERY)
+    time.sleep(2) # Wait for switch to settle

[dtu, 2011/05/27 23:33:43]

Does it take some time for it to notice that the line power is on/off? In that
case, use something like:
self.assertTrue(self.WaitUntil(lambda: self.GetBatteryInfo()['line_power_on']))
Just calling time.sleep() in tests is discouraged because the timing can change
across different builds or platforms, leading to a flaky test.

[scottc, 2011/05/31 15:40:21]

Removed.

+
+    # Get info about discharging battery
+    self.assertTrue(self.WaitUntilBatteryTimeIsCalculated(),
+        msg='Battery discharge time was not calculated.')
+    battery_status = self.GetBatteryInfo()
+    self.assertTrue(battery_status.get('battery_is_present'),
+        msg='Battery is not present.')
+    self.assertFalse(battery_status.get('line_power_on'),
+        msg='Line power is off.')
+    self.assertTrue(battery_status.get('battery_time_to_empty') >= 0,
+        msg='Battery discharge time is negative.')
+
+
+  def testBatteryTimesAreDifferent(self):
+    """Time until full is different than Time until empty"""
+    # Turn AC Power ON
+    self._power_strip.PowerOn(ChromeosBattery._OUTLET_WITH_BATTERY)
+    time.sleep(2)
+
+    # Get charging battery time to full
+    self.WaitUntilBatteryTimeIsCalculated()
+    battery_status = self.GetBatteryInfo()
+    time_to_full = battery_status.get('battery_time_to_full')
+
+    # Turn AC Power OFF
+    self._power_strip.PowerOff(ChromeosBattery._OUTLET_WITH_BATTERY)
+    time.sleep(2)
+
+    # Get discharging battery time to empty
+    self.WaitUntilBatteryTimeIsCalculated()
+    battery_status = self.GetBatteryInfo()
+    time_to_empty = battery_status.get('battery_time_to_empty')
+
+    # Compare times
+    self.assertNotEqual(time_to_full, time_to_empty,
+        msg='Battery time to full equals time to empty. '
+            'Though very unlikely, this is not impossible. '
+            'If test failed falsely, Kris ows Scott a beer. ')

[dtu, 2011/05/27 23:33:43]

owes*

[scottc, 2011/05/31 15:40:21]

Done.

+
+if __name__ == '__main__':
+  pyauto_functional.Main()