WIP for #32 - Added test for getting partial host list output in the case where the host lists contains one or more failing hosts. Refactored run_command to allow raising an exception on errors or not

Author: Dan

pssh.py

@@ -199,7 +199,8 @@ def _connect(self, client, host, port, sock=None, retries=1):
                                            str(error_type), self.host, self.port,
                                            retries, self.num_retries,)
         except paramiko.AuthenticationException, ex:
-            raise AuthenticationException(ex.message)
+            msg = ex.message + "Host is '%s:%s'"
+            raise AuthenticationException(msg, host, port)
         # SSHException is more general so should be below other types
         # of SSH failure
         except paramiko.SSHException, ex:
@@ -492,9 +493,19 @@ def run_command(self, *args, **kwargs):
                        'cmd'     : <greenlet>}}
 
         """
+        stop_on_errors = kwargs['stop_on_errors'] \
+          if 'stop_on_errors' in kwargs else True
+        del kwargs['stop_on_errors']
         cmds = [self.pool.spawn(self._exec_command, host, *args, **kwargs)
                 for host in self.hosts]
-        return self.get_output(commands=cmds)
+        output = {}
+        for cmd in cmds:
+            try:
+                output = self.get_output(cmd)
+            except Exception, ex:
+                if stop_on_errors:
+                    raise ex
+        return output
 
     def exec_command(self, *args, **kwargs):
         """Run command on all hosts in parallel, honoring `self.pool_size`
@@ -525,8 +536,8 @@ def _exec_command(self, host, *args, **kwargs):
                                                 proxy_port=self.proxy_port)
         return self.host_clients[host].exec_command(*args, **kwargs)
 
-    def get_output(self, commands=None):
-        """Get output from running commands.
+    def get_output(self, cmd):
+        """Get output from command.
         
         :param commands: (Optional) Override commands to get output from.\
         Uses running commands in pool if not given.
@@ -557,17 +568,23 @@ def get_output(self, commands=None):
         >>> self.get_exit_code(output[host])
         0
         """
-        if not commands:
-            commands = list(self.pool.greenlets)
         output = {}
-        for cmd in commands:
+        try:
             (channel, host, stdout, stderr) = cmd.get()
-            output.setdefault(host, {})
-            output[host].update({'exit_code': self._get_exit_code(channel),
-                                 'channel' : channel,
-                                 'stdout' : stdout,
-                                 'stderr' : stderr,
-                                 'cmd' : cmd, })
+        except Exception, ex:
+            output[host].update({'exit_code' : None,
+                                 'channel' : None,
+                                 'stdout' : None,
+                                 'stderr' : None,
+                                 'cmd' : cmd,
+                                 'exception' : ex,})
+            raise ex
+        output.setdefault(host, {})
+        output[host].update({'exit_code': self._get_exit_code(channel),
+                             'channel' : channel,
+                             'stdout' : stdout,
+                             'stderr' : stderr,
+                             'cmd' : cmd, })
         return output
 
     def get_exit_code(self, host_output):

pssh_local.py

@@ -23,7 +23,7 @@
 from pssh import SSHClient, ParallelSSHClient
 import logging
 
-logger = logging.getLogger(__name__)
+logger = logging.getLogger('pssh')
 
 def _setup_logger(_logger):
     """Setup default logger"""

tests/test_pssh_client.py

@@ -190,6 +190,35 @@ def test_pssh_client_auth_failure(self):
         del client
         server.join()
 
+    def test_pssh_client_hosts_list_part_failure(self):
+        """Test getting output for remainder of host list in the case where one
+        host in the host list has a failure"""
+        server2_socket = make_socket('127.0.0.2', port=self.listen_port)
+        server2_port = server2_socket.getsockname()[1]
+        server1 = start_server({ self.fake_cmd : self.fake_resp },
+                               self.listen_socket, fail_auth=True)
+        server2 = start_server({ self.fake_cmd : self.fake_resp },
+                               server2_socket)
+        hosts = ['127.0.0.1', '127.0.0.2']
+        client = ParallelSSHClient(hosts,
+                                   port=self.listen_port,
+                                   pkey=self.user_key,
+                                   )
+        output = {}
+        try:
+            client.run_command(self.fake_cmd,
+                               output=output,
+                               stop_on_errors=False)
+        except AuthenticationException:
+            pass
+        self.assertTrue(hosts[0] in output,
+                        msg="Failed host does not exist in output - output is %s" % (output,))
+        self.assertTrue(hosts[1] in output,
+                        msg="Successful host does not exist in output - output is %s" % (output,))
+        del client
+        server1.kill()
+        server2.kill()
+
     def test_pssh_client_ssh_exception(self):
         server = start_server({ self.fake_cmd : self.fake_resp },
                               self.listen_socket,