New module argument to specify the executable used for running 'pip'. This…

New module argument to specify the executable used for running 'pip'. This allows support for system installation of packages on systems with multiple installations of Python.

library/packaging/pip

@@ -97,6 +97,15 @@ options:
     version_added: "1.3"
     required: false
     default: null
+  executable:
+    description:
+      - The explicit executable or a pathname to the executable to be used to
+        run pip for a specific version of Python installed in the system. For
+        example C(pip-3.3), if there are both Python 2.7 and 3.3 installations
+        in the system and you want to run pip for the Python 3.3 installation.
+    version_added: "1.3"
+    required: false
+    default: null
 notes:
    - Please note that virtualenv (U(http://www.virtualenv.org/)) must be installed on the remote host if the virtualenv parameter is specified.
 requirements: [ "virtualenv", "pip" ]
@@ -130,6 +139,9 @@ EXAMPLES = '''
 
 # Install specified python requirements and custom Index URL.
 - pip: requirements=/my_app/requirements.txt extra_args='-i https://example.com/pypi/simple'
+
+# Install (Bottle) for Python 3.3 specifically,using the 'pip-3.3' executable.
+- pip: name=bottle executable=pip-3.3
 '''
 
 
@@ -141,21 +153,26 @@ def _get_full_name(name, version=None):
     return resp
 
 
-def _get_pip(module, env):
-    # On Debian and Ubuntu, pip is pip.
-    # On Fedora18 and up, pip is python-pip.
-    # On Fedora17 and below, CentOS and RedHat 6 and 5, pip is pip-python.
-    # On Fedora, CentOS, and RedHat, the exception is in the virtualenv.
-    # There, pip is just pip.
-    # Try pip with the virtualenv directory first.
-    pip = module.get_bin_path('pip', False, ['%s/bin' % env])
-    for p in ['python-pip', 'pip-python']:
+def _get_pip(module, env, executable=None):
+    if executable is None:
+        # Default pip executables.
+        # On Debian and Ubuntu, pip is pip.
+        # On Fedora18 and up, pip is python-pip.
+        # On Fedora17 and below, CentOS and RedHat 6 and 5, pip is pip-python.
+        # On Fedora, CentOS, and RedHat, the exception is in the virtualenv.
+        # There, pip is just pip.
+        # Try pip with the virtualenv directory first.
+        pip = module.get_bin_path('pip', False, ['%s/bin' % env])
+        for p in ['python-pip', 'pip-python']:
+            if not pip:
+                pip = module.get_bin_path(p, False, ['%s/bin' % env])
+        # pip should have been found by now.  The final call to get_bin_path
+        # will trigger fail_json.
         if not pip:
-            pip = module.get_bin_path(p, False, ['%s/bin' % env])
-    # pip should have been found by now.  The final call to get_bin_path
-    # will trigger fail_json.
-    if not pip:
-        pip = module.get_bin_path('pip', True, ['%s/bin' % env])
+            pip = module.get_bin_path('pip', True, ['%s/bin' % env])
+    else:
+        # Explicit pip executable.
+        pip = module.get_bin_path(executable, True)
     return pip
 
 
@@ -187,6 +204,7 @@ def main():
             use_mirrors=dict(default='yes', type='bool'),
             extra_args=dict(default=None, required=False),
             chdir=dict(default=None, required=False),
+            executable=dict(default=None, required=False),
         ),
         required_one_of=[['name', 'requirements']],
         mutually_exclusive=[['name', 'requirements']],
@@ -231,7 +249,7 @@ def main():
             if rc != 0:
                 _fail(module, cmd, out, err)
 
-    pip = _get_pip(module, env)
+    pip = _get_pip(module, env, module.params['executable'])
 
     cmd = '%s %s' % (pip, state_map[state])