Add SSH Action

* We need an another way to communicate with VM,
   so SSH is this way. Also it gives a possibility
   to check if VM operation system is up by sending
   a simple ssh command to it.
 * Added SSH Action
 * Only password access, forwarding public/private keys
   will be in the future
 * It is tested on real VM. However, it needs to be tested
   by somebody else

Implements blueprint mistral-ssh-action

Change-Id: I7c51453afb6a926bbce01f4a9065a3c313a79fff

mistral/engine/actions/action_factory.py

@@ -48,7 +48,8 @@ def _get_mapping():
         action_types.REST_API: get_rest_action,
         action_types.MISTRAL_REST_API: get_mistral_rest_action,
         action_types.OSLO_RPC: get_amqp_action,
-        action_types.SEND_EMAIL: get_send_email_action
+        action_types.SEND_EMAIL: get_send_email_action,
+        action_types.SSH: get_ssh_action
     }
 
 
@@ -143,3 +144,23 @@ def get_send_email_action(db_task, task, service):
 
     return actions.SendEmailAction(action_type, action_name,
                                    task_params, service_params)
+
+
+def get_ssh_action(db_task, task, service):
+    action_type = service.type
+    action_name = task.get_action_name()
+    task_params = task.parameters
+    action = service.actions.get(action_name)
+    action_params = action.parameters
+
+    # Merge/replace action_params by task_params.
+    all_params = copy.copy(action_params)
+    all_params.update(task_params)
+
+    cmd = all_params['cmd']
+    host = all_params['host']
+    username = all_params['username']
+    password = all_params['password']
+
+    return actions.SSHAction(action_type, action_name, cmd,
+                             host, username, password)

mistral/engine/actions/action_types.py

@@ -22,8 +22,9 @@ REST_API = 'REST_API'
 OSLO_RPC = 'OSLO_RPC'
 MISTRAL_REST_API = 'MISTRAL_REST_API'
 SEND_EMAIL = "SEND_EMAIL"
+SSH = "SSH"
 
-_ALL = [ECHO, REST_API, OSLO_RPC, MISTRAL_REST_API, SEND_EMAIL]
+_ALL = [ECHO, REST_API, OSLO_RPC, MISTRAL_REST_API, SEND_EMAIL, SSH]
 
 
 def is_valid(action_type):

mistral/engine/actions/actions.py

@@ -28,6 +28,7 @@ import six
 from mistral.openstack.common import log as logging
 from mistral.engine import expressions as expr
 from mistral import exceptions as exc
+from mistral.utils import ssh_utils
 
 
 LOG = logging.getLogger(__name__)
@@ -211,3 +212,32 @@ class SendEmailAction(Action):
         except (smtplib.SMTPException, IOError) as e:
             raise exc.ActionException("Failed to send an email message: %s"
                                       % e)
+
+
+class SSHAction(Action):
+    def __init__(self, action_type, action_name,
+                 cmd, host, username, password):
+        super(SSHAction, self).__init__(action_type, action_name)
+        self.cmd = cmd
+        self.host = host
+        self.username = username
+        self.password = password
+
+    def run(self):
+        def raise_exc(parent_exc=None):
+            message = ("Failed to execute ssh cmd "
+                       "'%s' on %s" % (self.cmd, self.host))
+            if parent_exc:
+                message += "\nException: %s" % str(parent_exc)
+            raise exc.ActionException(message)
+
+        try:
+            status_code, result = ssh_utils.execute_command(self.cmd,
+                                                            self.host,
+                                                            self.username,
+                                                            self.password)
+            if status_code > 0:
+                return raise_exc()
+            return result
+        except Exception as e:
+            return raise_exc(parent_exc=e)

mistral/tests/unit/engine/actions/test_action_factory.py

@@ -14,6 +14,7 @@
 #    See the License for the specific language governing permissions and
 #    limitations under the License.
 
+import copy
 import json
 import unittest2
 
@@ -136,3 +137,21 @@ class ActionFactoryTest(unittest2.TestCase):
         action = action_factory.create_action(task)
         self.assertIn("X-Auth-Token", action.headers)
         self.assertEqual(auth_token, action.headers["X-Auth-Token"])
+
+    def test_get_ssh_action(self):
+        task = copy.copy(SAMPLE_TASK)
+        task['service_spec'].update({'type': action_types.SSH})
+        create_vm = task['service_spec']['actions']['create-vm']
+        create_vm['parameters'].update({'host': '10.0.0.1',
+                                        'cmd': 'ls -l'})
+        task_params = task['task_spec']['parameters']
+        task_params.update({'username': '$.ssh_username',
+                            'password': '$.ssh_password'})
+        task['in_context'] = {'ssh_username': 'ubuntu',
+                              'ssh_password': 'ubuntu_password'}
+        action = action_factory.create_action(task)
+
+        self.assertEqual("ubuntu", action.username)
+        self.assertEqual("ubuntu_password", action.password)
+        self.assertEqual("ls -l", action.cmd)
+        self.assertEqual("10.0.0.1", action.host)

mistral/utils/ssh_utils.py

@@ -0,0 +1,71 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright 2014 - Mirantis, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License");
+#    you may not use this file except in compliance with the License.
+#    You may obtain a copy of the License at
+#
+#        http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS,
+#    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#    See the License for the specific language governing permissions and
+#    limitations under the License.
+
+import paramiko
+
+from mistral.openstack.common import log as logging
+
+
+LOG = logging.getLogger(__name__)
+
+
+def _read_paramimko_stream(recv_func):
+    result = ''
+    buf = recv_func(1024)
+    while buf != '':
+        result += buf
+        buf = recv_func(1024)
+
+    return result
+
+
+def _connect(host, username, password):
+    LOG.debug('Creating SSH connection to %s' % host)
+    ssh = paramiko.SSHClient()
+    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+    ssh.connect(host, username=username, password=password)
+    return ssh
+
+
+def _cleanup(ssh):
+    ssh.close()
+
+
+def execute_command(cmd, host, username, password,
+                    get_stderr=False, raise_when_error=True):
+    ssh = _connect(host, username, password)
+
+    LOG.debug("Executing command %s")
+
+    try:
+        chan = ssh.get_transport().open_session()
+        chan.exec_command(cmd)
+
+        # TODO (nmakhotkin): that could hang if stderr buffer overflows
+        stdout = _read_paramimko_stream(chan.recv)
+        stderr = _read_paramimko_stream(chan.recv_stderr)
+
+        ret_code = chan.recv_exit_status()
+
+        if ret_code and raise_when_error:
+            raise RuntimeError("Cmd: %s\nReturn code: %s\nstdout: %s"
+                               % (cmd, ret_code, stdout))
+        if get_stderr:
+            return ret_code, stdout, stderr
+        else:
+            return ret_code, stdout
+    finally:
+        _cleanup(ssh)

requirements.txt

@@ -10,6 +10,7 @@ requests
 kombu>=2.4.8
 oslo.config>=1.2.0
 oslo.messaging>=1.3.0a4
+paramiko>=1.9.0
 python-keystoneclient>=0.3.2
 networkx
 six>=1.5.2