From c55adc9ac9d4e67aeeb1b0e1d58e4e013538f164 Mon Sep 17 00:00:00 2001
From: Michael DeHaan <michael@ansibleworks.com>
Date: Thu, 4 Jul 2013 16:47:17 -0400
Subject: [PATCH] Default to 'smart' transport, which will use OpenSSH if it
 can support ControlPersist.

---
 examples/ansible.cfg           |  2 +-
 lib/ansible/constants.py       |  2 +-
 lib/ansible/runner/__init__.py | 13 ++++++++++++-
 3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/examples/ansible.cfg b/examples/ansible.cfg
index d505bf0ccf3..0e9e91de14a 100644
--- a/examples/ansible.cfg
+++ b/examples/ansible.cfg
@@ -19,7 +19,7 @@ poll_interval  = 15
 sudo_user      = root
 #ask_sudo_pass = True
 #ask_pass      = True
-transport      = paramiko
+transport      = smart
 remote_port    = 22
 
 # uncomment this to disable SSH key host checking
diff --git a/lib/ansible/constants.py b/lib/ansible/constants.py
index 82f5d7a7dfe..3351c6f661b 100644
--- a/lib/ansible/constants.py
+++ b/lib/ansible/constants.py
@@ -104,7 +104,7 @@ DEFAULT_PRIVATE_KEY_FILE  = shell_expand_path(get_config(p, DEFAULTS, 'private_k
 DEFAULT_SUDO_USER         = get_config(p, DEFAULTS, 'sudo_user',        'ANSIBLE_SUDO_USER',        'root')
 DEFAULT_ASK_SUDO_PASS     = get_config(p, DEFAULTS, 'ask_sudo_pass',    'ANSIBLE_ASK_SUDO_PASS',    False, boolean=True)
 DEFAULT_REMOTE_PORT       = int(get_config(p, DEFAULTS, 'remote_port',      'ANSIBLE_REMOTE_PORT',      22))
-DEFAULT_TRANSPORT         = get_config(p, DEFAULTS, 'transport',        'ANSIBLE_TRANSPORT',        'paramiko')
+DEFAULT_TRANSPORT         = get_config(p, DEFAULTS, 'transport',        'ANSIBLE_TRANSPORT',        'smart')
 DEFAULT_SCP_IF_SSH        = get_config(p, 'ssh_connection', 'scp_if_ssh',       'ANSIBLE_SCP_IF_SSH',       False, boolean=True)
 DEFAULT_MANAGED_STR       = get_config(p, DEFAULTS, 'ansible_managed',  None,           'Ansible managed: {file} modified on %Y-%m-%d %H:%M:%S by {uid} on {host}')
 DEFAULT_SYSLOG_FACILITY   = get_config(p, DEFAULTS, 'syslog_facility',  'ANSIBLE_SYSLOG_FACILITY', 'LOG_USER')
diff --git a/lib/ansible/runner/__init__.py b/lib/ansible/runner/__init__.py
index 7e0bf0de029..93c1070889e 100644
--- a/lib/ansible/runner/__init__.py
+++ b/lib/ansible/runner/__init__.py
@@ -31,6 +31,7 @@ import sys
 import shlex
 import pipes
 import jinja2
+import subprocess
 
 import ansible.constants as C
 import ansible.inventory
@@ -169,9 +170,19 @@ class Runner(object):
         self.environment      = environment
         self.complex_args     = complex_args
         self.error_on_undefined_vars = error_on_undefined_vars
-
         self.callbacks.runner = self
 
+        # if the transport is 'smart' see if SSH can support ControlPersist if not use paramiko
+        # 'smart' is the default since 1.2.1/1.3
+        if self.transport == 'smart':
+            cmd = subprocess.Popen(['ssh','-o','ControlPersist'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+            (out, err) = cmd.communicate() 
+            if "Bad configuration option" in err:
+                self.transport = "paramiko"
+            else:
+                self.transport = "ssh" 
+
+
         # misc housekeeping
         if subset and self.inventory._subset is None:
             # don't override subset when passed from playbook