telnet action plugin (#27983)

* draft telnet action plugin

docs in module

* updated per feedback

* fixed imports

* pep8 fixes

* added meta import even though its useless

lib/ansible/modules/commands/telnet.py

@@ -0,0 +1,75 @@
+# this is a virtual module that is entirely implemented server side
+# Copyright: Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import absolute_import, division, print_function
+__metaclass__ = type
+
+ANSIBLE_METADATA = {'metadata_version': '1.0',
+                    'status': ['preview'],
+                    'supported_by': 'community'}
+
+DOCUMENTATION = '''
+---
+module: telnet
+short_description: Executes a low-down and dirty telnet command
+version_added: 2.4
+description:
+     - Executes a low-down and dirty telnet command, not going through the module subsystem.
+     - This is mostly to be used for enabling ssh on devices that only have telnet enabled by default.
+options:
+  commands:
+    description:
+      - List of commands to be executed in the telnet session.
+    required: True
+  host:
+    description:
+        - The host/target on which to execute the command
+    required: False
+    default: remote_addr
+  user:
+    description:
+        - The user for login
+    required: False
+    default: remote_user
+  password:
+    description:
+        - The password for login
+  port:
+    description:
+        - Remote port to use
+    default: 23
+  timeout:
+    description:
+        - timeout for remote operations
+    default: 120
+  command:
+    description:
+        - Command to execute in telnet session
+    required: True
+  pause:
+    description:
+        - Seconds to pause between each command issued
+    required: False
+    default: 1
+notes:
+    - The C(environment) keyword does not work with this task
+author:
+    - Ansible Core Team
+'''
+
+EXAMPLES = '''
+- name: Force ssh on IOS
+  telnet:
+    command: transport input ssh
+    user: cisco
+    password: cisco
+'''
+
+RETURN = '''
+output:
+    description: output of each command is an element in this list
+    type: list
+    returned: always
+    sample: [ 'success', 'success', '', 'warning .. something' ]
+'''

lib/ansible/plugins/action/telnet.py

@@ -0,0 +1,81 @@
+# (c) 2017, Ansible Project
+#
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+#
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+import telnetlib
+from time import sleep
+
+from ansible.module_utils._text import to_native
+from ansible.module_utils.six import text_type
+from ansible.plugins.action import ActionBase
+
+
+class ActionModule(ActionBase):
+    TRANSFERS_FILES = False
+
+    def run(self, tmp=None, task_vars=None):
+
+        if self._task.environment and any(self._task.environment):
+            self._display.warning('The telnet task does not support the environment keyword')
+
+        result = super(ActionModule, self).run(tmp, task_vars)
+
+        if self._play_context.check_mode:
+            # in --check mode, always skip this module execution
+            result['skipped'] = True
+            result['msg'] = 'The telnet task does not support check mode'
+        else:
+            result['changed'] = True
+            result['failed'] = False
+
+            host = self._task.args.get('host', self._play_context.remote_addr)
+            user = self._task.args.get('user', self._play_context.remote_user)
+            password = self._task.args.get('password', self._play_context.password)
+
+            # FIXME, default to play_context?
+            port = self._task.args.get('port', '23')
+            timeout = self._task.args.get('timeout', 120)
+            pause = self._task.args.get('pause', 1)
+
+            login_prompt = self._task.args.get('login_prompt', "login: ")
+            password_prompt = self._task.args.get('password_prompt', "Password: ")
+            commands = self._task.args.get('command')
+
+            if isinstance(commands, text_type):
+                commands = commands.split(',')
+
+            if isinstance(commands, list) and commands:
+
+                tn = telnetlib.Telnet(host, port, timeout)
+
+                output = []
+                try:
+                    tn.read_until(login_prompt)
+                    tn.write('%s\n' % user)
+
+                    if password:
+                        tn.read_until(password_prompt)
+                        tn.write('%s\n' % password)
+
+                    for cmd in commands:
+                        tn.write(cmd)
+                        output.append(tn.read_until(''))
+                        sleep(pause)
+
+                    tn.write("exit\n")
+
+                except EOFError as e:
+                    result['failed'] = True
+                    result['msg'] = 'Telnet action failed: %s' % to_native(e)
+                finally:
+                    if tn:
+                        tn.close()
+                    result['output'] = output
+            else:
+                result['failed'] = True
+                result['msg'] = 'Telnet requries a command to execute'
+
+        return result