GetServicePath should perform a scan

chrome/test/pyautolib/pyauto.py

Index: chrome/test/pyautolib/pyauto.py
diff --git a/chrome/test/pyautolib/pyauto.py b/chrome/test/pyautolib/pyauto.py
index 2c95c63cbad9567df7c988654821db5f21eb3cee..8f344f751d441f8716cce34e90bc6d18f1cce97d 100755
--- a/chrome/test/pyautolib/pyauto.py
+++ b/chrome/test/pyautolib/pyauto.py
@@ -5064,20 +5064,30 @@ class PyUITest(pyautolib.PyUITestBase, unittest.TestCase):
        connected_service_path in service_list['wifi_networks']:
        return service_list['wifi_networks'][connected_service_path]['name']
 
-  def GetServicePath(self, ssid):
+  def GetServicePath(self, ssid, encryption=None, timeout=30):
     """Returns the service path associated with an SSID.
 
     Args:
       ssid: String defining the SSID we are searching for.
+      encryption: Encryption type of the network; either None to return the
+                  first instance of network that matches the ssid, '' for
+                  an empty network, 'PSK', 'WEP' or '8021X'.
+      timeout: Duration to wait for ssid to appear.
 
     Returns:
-      The service path or None if SSID does not exist.
-    """
-    service_list = self.GetNetworkInfo()
-    service_list = service_list.get('wifi_networks', [])
-    for service_path, service_obj in service_list.iteritems():
-      if service_obj['name'] == ssid:
-        return service_path
+      The service path or None if SSID does not exist after timeout period.
+    """
+    end_time = time.time() + timeout
+    while time.time() < end_time:

[krisr, 2012/08/06 23:39:13]

How fast does this spin?  i.e. are we spiking the CPU and we burn through this
loop or is NetworkScan slow enough we don't own the device?

[stanleyw, 2012/08/07 01:22:13]

Done.

+      service_list = self.GetNetworkInfo().get('wifi_networks', [])
+      for service_path, service_obj in service_list.iteritems():
+        service_encr = 'PSK' if service_obj['encryption'] in ['WPA', 'RSN'] \
+                       else service_obj['encryption']
+
+        if service_obj['name'] == ssid and \
+           (encryption == None or service_encr == encryption):
+          return service_path
+      self.NetworkScan()
     return None
 
   def NetworkScan(self):