Improve resiliency for Android.

appengine/swarming/swarming_bot/api/platforms/android.py

 # Copyright 2015 The Swarming Authors. All rights reserved.
 # Use of this source code is governed by the Apache v2.0 license that can be
 # found in the LICENSE file.
 
 """Android specific utility functions.
 
 This file serves as an API to bot_config.py. bot_config.py can be replaced on
 the server to allow additional server-specific functionality.
 """
 
 import logging
 import os
 import re
 import subprocess
 import sys
 import time
 
-# This file must be imported from swarming_bot.zip (or with '..' in sys.path).
-# libusb1 must have been put in the path already.
+# This file must be imported from swarming_bot.zip (or with '../..' in
+# sys.path). libusb1 must have been put in the path already.
 
 import adb
 import adb.adb_commands
 
 
 # Find abs path to third_party/ dir in the bot root dir.
 import third_party
 THIRD_PARTY_DIR = os.path.dirname(os.path.abspath(third_party.__file__))
 sys.path.insert(0, os.path.join(THIRD_PARTY_DIR, 'rsa'))
 sys.path.insert(0, os.path.join(THIRD_PARTY_DIR, 'pyasn1'))
@@ skipping 418 matching lines @@
       for line in out.splitlines():
         if line.startswith(u'#') or not line:
           continue
         key, value = line.split(u'=', 1)
         properties[key] = value
     _BUILD_PROP_ANDROID[device.serial] = properties
   return _BUILD_PROP_ANDROID[device.serial]
 
 
 def get_temp(device):
-  """Returns the device's 2 temperatures if available."""
+  """Returns the device's 2 temperatures if available.
+
+  Returns None otherwise.
+  """
+  assert isinstance(device, Device), device
   # Not all devices export this file. On other devices, the only real way to
   # read it is via Java
   # developer.android.com/guide/topics/sensors/sensors_environment.html
   temps = []
-  for i in xrange(2):
-    out, _ = device.shell('cat /sys/class/thermal/thermal_zone%d/temp' % i)
-    if out:
+  try:
+    for i in xrange(2):
+      out, _ = device.shell('cat /sys/class/thermal/thermal_zone%d/temp' % i)
       temps.append(int(out))
+  except ValueError:
+    return None
   return temps
 
 
 def get_battery(device):
   """Returns details about the battery's state."""
+  assert isinstance(device, Device), device
   props = {}
   out = _dumpsys(device, 'battery')
   if not out:
     return props
   for line in out.splitlines():
     if line.endswith(u':'):
       continue
     # On Android 4.1.2, it uses "voltage:123" instead of "voltage: 123".
-    key, value = line.split(u':', 2)
-    props[key.lstrip()] = value.strip()
+    parts = line.split(u':', 2)
+    if len(parts) == 2:
+      key, value = parts
+      props[key.lstrip()] = value.strip()
   out = {u'power': []}
-  if props[u'AC powered'] == u'true':
+  if props.get(u'AC powered') == u'true':
     out[u'power'].append(u'AC')
-  if props[u'USB powered'] == u'true':
+  if props.get(u'USB powered') == u'true':
     out[u'power'].append(u'USB')
   if props.get(u'Wireless powered') == u'true':
     out[u'power'].append(u'Wireless')
   for key in (u'health', u'level', u'status', u'temperature', u'voltage'):
     out[key] = int(props[key])
   return out
 
 
 def get_cpu_scale(device):
   """Returns the CPU scaling factor."""
+  assert isinstance(device, Device), device
   mapping = {
     'cpuinfo_max_freq': u'max',
     'cpuinfo_min_freq': u'min',
     'scaling_cur_freq': u'cur',
     'scaling_governor': u'governor',
   }
   return {
     v: device.shell('cat /sys/devices/system/cpu/cpu0/cpufreq/' + k)[0]
     for k, v in mapping.iteritems()
   }
 
 
 def get_uptime(device):
   """Returns the device's uptime in second."""
+  assert isinstance(device, Device), device
   out, _ = device.shell('cat /proc/uptime')
   if out:
     return float(out.split()[1])
   return None
 
 
 def get_disk(device):
   """Returns details about the battery's state."""
+  assert isinstance(device, Device), device
   props = {}
   out = _dumpsys(device, 'diskstats')
   if not out:
     return props
   for line in out.splitlines():
     if line.endswith(u':'):
       continue
-    key, value = line.split(u': ', 2)
-    match = re.match(u'^(\d+)K / (\d+)K.*', value)
-    if match:
-      props[key.lstrip()] = {
-        'free_mb': round(float(match.group(1)) / 1024., 1),
-        'size_mb': round(float(match.group(2)) / 1024., 1),
-      }
+    parts = line.split(u': ', 2)
+    if len(parts) == 2:
+      key, value = parts
+      match = re.match(u'^(\d+)K / (\d+)K.*', value)
+      if match:
+        props[key.lstrip()] = {
+          'free_mb': round(float(match.group(1)) / 1024., 1),
+          'size_mb': round(float(match.group(2)) / 1024., 1),
+        }
   return {
     u'cache': props[u'Cache-Free'],
     u'data': props[u'Data-Free'],
     u'system': props[u'System-Free'],
   }
 
 
 def get_imei(device):
   """Returns the phone's IMEI."""
+  assert isinstance(device, Device), device
   # Android <5.0.
   out = _dumpsys(device, 'iphonesubinfo')
   if out:
     match = re.search('  Device ID = (.+)$', out)
     if match:
       return match.group(1)
 
   # Android >= 5.0.
   out, _ = device.shell('service call iphonesubinfo 1')
   if out:
     lines = out.splitlines()
     if len(lines) >= 4 and lines[0] == 'Result: Parcel(':
       # Process the UTF-16 string.
       chars = _parcel_to_list(lines[1:])[4:-1]
       return u''.join(map(unichr, (int(i, 16) for i in chars)))
   return None
 
 
 def get_ip(device):
   """Returns the IP address."""
+  assert isinstance(device, Device), device
   # If ever needed, read wifi.interface from /system/build.prop if a device
   # doesn't use wlan0.
   ip, _ = device.shell('getprop dhcp.wlan0.ipaddress')
   if not ip:
     return None
   return ip.strip()