Refactoring remote client to use new ping methods

* Removed obsolete _is_instance_reachable method
* Updated connectivity checks in Windows and Linux remote client code
  to use new ping_until_reachable method
* Added InvalidAddressFormat exception

Change-Id: I588e26a16e8f9b829c48177a35ff8d816f97bcf9

cloudcafe/compute/common/clients/remote_instance/base_client.py

@@ -1,10 +1,7 @@
 import abc
-import time
 
 from cafe.engine.clients.base import BaseClient
 
-from cloudcafe.compute.common.clients.ping import PingClient
-
 
 class RemoteInstanceClient(BaseClient):
     __metaclass__ = abc.ABCMeta
@@ -60,16 +57,3 @@ class RemoteInstanceClient(BaseClient):
     def can_authenticate(self):
         """Verifies a remote connection can be made to the server."""
         raise NotImplementedError
-
-    @staticmethod
-    def _is_instance_reachable(ip_address, retry_interval, timeout):
-        """Verify the server can be pinged."""
-        start = int(time.time())
-        reachable = False
-        while not reachable:
-            reachable = PingClient.ping(ip_address)
-            if reachable:
-                return True
-            time.sleep(retry_interval)
-            if int(time.time()) - start >= timeout:
-                return False

cloudcafe/compute/common/clients/remote_instance/linux/linux_client.py

@@ -18,8 +18,7 @@ import os
 import re
 import time
 
-from cloudcafe.common.tools import datagen
+from IPy import IP
-
 from cafe.common.reporting import cclogging
 from cafe.engine.clients.remote_instance.exceptions \
     import DirectoryNotFoundException
@@ -28,11 +27,12 @@ from cafe.engine.clients.remote_instance.models.dir_details \
 from cafe.engine.clients.remote_instance.models.file_details \
     import FileDetails
 from cafe.engine.ssh.client import SSHAuthStrategy, SSHClient
+from cloudcafe.common.tools import datagen
 from cloudcafe.compute.common.clients.ping import PingClient
 from cloudcafe.compute.common.clients.remote_instance.base_client import \
     RemoteInstanceClient
 from cloudcafe.compute.common.exceptions import FileNotFoundException, \
-    ServerUnreachable, SshConnectionException
+    SshConnectionException, InvalidAddressFormat
 from cloudcafe.common.tools.md5hash import get_md5_hash
 
 
@@ -43,25 +43,21 @@ class LinuxClient(RemoteInstanceClient):
         self.client_log = cclogging.getLogger(
             cclogging.get_object_namespace(self.__class__))
 
-        if ip_address is None:
-            raise ServerUnreachable("None")
         self.ip_address = ip_address
         self.username = username
         self.password = password
         self.connection_timeout = connection_timeout
 
+        # Verify the IP address has a valid format
+        try:
+            IP(ip_address)
+        except ValueError:
+            raise InvalidAddressFormat(ip_address)
+
         # Verify the server can be pinged before attempting to connect
-        start = int(time.time())
+        PingClient.ping_until_reachable(ip_address,
-        reachable = False
+                                        timeout=connection_timeout,
-        while not reachable:
+                                        interval_time=retry_interval)
-            reachable = PingClient.ping(ip_address)
-            if reachable:
-                break
-            time.sleep(retry_interval)
-            if int(time.time()) - start >= connection_timeout:
-                raise ServerUnreachable(
-                    'Could not reach the server at {ip_address}'.format(
-                        ip_address=ip_address))
 
         if key is not None:
             auth_strategy = SSHAuthStrategy.KEY_STRING

cloudcafe/compute/common/clients/remote_instance/windows/windows_client.py

@@ -18,17 +18,18 @@ from dateutil.parser import parse
 import re
 
 from IPy import IP
-
 from cafe.engine.clients.winrm_client import WinRMClient
 from cafe.common.reporting import cclogging
 from cafe.engine.clients.remote_instance.models.dir_details \
     import DirectoryDetails
 from cafe.engine.clients.remote_instance.models.file_details \
     import FileDetails
+
+from cloudcafe.compute.common.clients.ping import PingClient
 from cloudcafe.compute.common.clients.remote_instance.base_client import \
     RemoteInstanceClient
-from cloudcafe.compute.common.exceptions import ServerUnreachable, \
+from cloudcafe.compute.common.exceptions import WinRMConnectionException, \
-    WinRMConnectionException
+    InvalidAddressFormat
 
 
 class WindowsClient(RemoteInstanceClient):
@@ -45,14 +46,12 @@ class WindowsClient(RemoteInstanceClient):
         try:
             IP(ip_address)
         except ValueError:
-            raise ServerUnreachable(ip_address)
+            raise InvalidAddressFormat(ip_address)
 
-        if not self._is_instance_reachable(
+        # Verify the server can be pinged before attempting to connect
-                ip_address=ip_address, retry_interval=retry_interval,
+        PingClient.ping_until_reachable(ip_address,
-                timeout=connection_timeout):
+                                        timeout=connection_timeout,
-            raise ServerUnreachable(
+                                        interval_time=retry_interval)
-                'Could not reach the server at {ip_address}'.format(
-                    ip_address=ip_address))
 
         self.ip_address = ip_address
         self.username = username

cloudcafe/compute/common/exceptions.py

@@ -180,6 +180,16 @@ class ServerUnreachable(Exception):
         return repr(self.message)
 
 
+class InvalidAddressFormat(Exception):
+    def __init__(self, ip_address):
+        self.message = (
+            'Invalid IP address provided: {ip_address}').format(
+                ip_address=ip_address)
+
+    def __str__(self):
+        return repr(self.message)
+
+
 class InvalidJSON(Exception):
     def __init__(self, message, expected_response):
         self.message = ('Unexpected JSON response. '