issue #291: support UNIX hashbang syntax for ansible_*_interpreter.

Closes #291.

ansible_mitogen/connection.py

@@ -44,9 +44,10 @@ import ansible.utils.shlex
 import mitogen.unix
 import mitogen.utils
 
-import ansible_mitogen.target
+import ansible_mitogen.parsing
 import ansible_mitogen.process
 import ansible_mitogen.services
+import ansible_mitogen.target
 
 
 LOG = logging.getLogger(__name__)
@@ -248,6 +249,20 @@ CONNECTION_METHOD = {
 }
 
 
+def parse_python_path(s):
+    """
+    Given the string set for ansible_python_interpeter, parse it as hashbang
+    syntax and return an appropriate argument vector.
+    """
+    if not s:
+        return None
+
+    interpreter, arg = ansible_mitogen.parsing.parse_script_interpreter(s)
+    if arg:
+        return [interpreter, arg]
+    return [interpreter]
+
+
 def config_from_play_context(transport, inventory_name, connection):
     """
     Return a dict representing all important connection configuration, allowing
@@ -265,7 +280,7 @@ def config_from_play_context(transport, inventory_name, connection):
         'become_pass': connection._play_context.become_pass,
         'password': connection._play_context.password,
         'port': connection._play_context.port,
-        'python_path': connection.python_path,
+        'python_path': parse_python_path(connection.python_path),
         'private_key_file': connection._play_context.private_key_file,
         'ssh_executable': connection._play_context.ssh_executable,
         'timeout': connection._play_context.timeout,
@@ -314,7 +329,7 @@ def config_from_hostvars(transport, inventory_name, connection,
         'password': (hostvars.get('ansible_ssh_pass') or
                      hostvars.get('ansible_password')),
         'port': hostvars.get('ansible_port'),
-        'python_path': hostvars.get('ansible_python_interpreter'),
+        'python_path': parse_python_path(hostvars.get('ansible_python_interpreter')),
         'private_key_file': (hostvars.get('ansible_ssh_private_key_file') or
                              hostvars.get('ansible_private_key_file')),
         'mitogen_via': hostvars.get('mitogen_via'),

ansible_mitogen/parsing.py

@@ -0,0 +1,84 @@
+# Copyright 2017, David Wilson
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice,
+# this list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+# this list of conditions and the following disclaimer in the documentation
+# and/or other materials provided with the distribution.
+#
+# 3. Neither the name of the copyright holder nor the names of its contributors
+# may be used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+"""
+Classes to detect each case from [0] and prepare arguments necessary for the
+corresponding Runner class within the target, including preloading requisite
+files/modules known missing.
+
+[0] "Ansible Module Architecture", developing_program_flow_modules.html
+"""
+
+from __future__ import absolute_import
+from __future__ import unicode_literals
+
+import mitogen.core
+
+
+def parse_script_interpreter(source):
+    """
+    Parse the script interpreter portion of a UNIX hashbang using the rules
+    Linux uses.
+
+    :param str source: String like "/usr/bin/env python".
+
+    :returns:
+        Tuple of `(interpreter, arg)`, where `intepreter` is the script
+        interpreter and `arg` is its sole argument if present, otherwise
+        :py:data:`None`.
+    """
+    # Find terminating newline. Assume last byte of binprm_buf if absent.
+    nl = source.find(b'\n', 0, 128)
+    if nl == -1:
+        nl = min(128, len(source))
+
+    # Split once on the first run of whitespace. If no whitespace exists,
+    # bits just contains the interpreter filename.
+    bits = source[0:nl].strip().split(None, 1)
+    if len(bits) == 1:
+        return mitogen.core.to_text(bits[0]), None
+    return mitogen.core.to_text(bits[0]), mitogen.core.to_text(bits[1])
+
+
+def parse_hashbang(source):
+    """
+    Parse a UNIX "hashbang line" using the syntax supported by Linux.
+
+    :param str source: String like "#!/usr/bin/env python".
+
+    :returns:
+        Tuple of `(interpreter, arg)`, where `intepreter` is the script
+        interpreter and `arg` is its sole argument if present, otherwise
+        :py:data:`None`.
+    """
+    # Linux requires first 2 bytes with no whitespace, pretty sure it's the
+    # same everywhere. See binfmt_script.c.
+    if not source.startswith(b'#!'):
+        return None, None
+
+    return parse_script_interpreter(source[2:])

ansible_mitogen/planner.py

@@ -48,6 +48,7 @@ import ansible.module_utils
 import mitogen.core
 
 import ansible_mitogen.loaders
+import ansible_mitogen.parsing
 import ansible_mitogen.target
 
 
@@ -56,34 +57,6 @@ NO_METHOD_MSG = 'Mitogen: no invocation method found for: '
 NO_INTERPRETER_MSG = 'module (%s) is missing interpreter line'
 
 
-def parse_script_interpreter(source):
-    """
-    Extract the script interpreter and its sole argument from the module
-    source code.
-
-    :returns:
-        Tuple of `(interpreter, arg)`, where `intepreter` is the script
-        interpreter and `arg` is its sole argument if present, otherwise
-        :py:data:`None`.
-    """
-    # Linux requires first 2 bytes with no whitespace, pretty sure it's the
-    # same everywhere. See binfmt_script.c.
-    if not source.startswith(b'#!'):
-        return None, None
-
-    # Find terminating newline. Assume last byte of binprm_buf if absent.
-    nl = source.find(b'\n', 0, 128)
-    if nl == -1:
-        nl = min(128, len(source))
-
-    # Split once on the first run of whitespace. If no whitespace exists,
-    # bits just contains the interpreter filename.
-    bits = source[2:nl].strip().split(None, 1)
-    if len(bits) == 1:
-        return mitogen.core.to_text(bits[0]), None
-    return mitogen.core.to_text(bits[0]), mitogen.core.to_text(bits[1])
-
-
 class Invocation(object):
     """
     Collect up a module's execution environment then use it to invoke
@@ -215,7 +188,7 @@ class ScriptPlanner(BinaryPlanner):
     detection and rewrite.
     """
     def _get_interpreter(self):
-        interpreter, arg = parse_script_interpreter(
+        interpreter, arg = ansible_mitogen.parsing.parse_hashbang(
             self._inv.module_source
         )
         if interpreter is None:

tests/ansible/integration/runner/all.yml

@@ -1,6 +1,7 @@
 - import_playbook: builtin_command_module.yml
 - import_playbook: custom_bash_old_style_module.yml
 - import_playbook: custom_bash_want_json_module.yml
+- import_playbook: custom_bash_hashbang_argument.yml
 - import_playbook: custom_binary_producing_json.yml
 - import_playbook: custom_binary_producing_junk.yml
 - import_playbook: custom_binary_single_null.yml

tests/ansible/integration/runner/custom_bash_hashbang_argument.yml

@@ -0,0 +1,19 @@
+# https://github.com/dw/mitogen/issues/291
+- name: integration/runner/custom_bash_hashbang_argument.yml
+  hosts: test-targets
+  any_errors_fatal: true
+  tasks:
+
+    - custom_bash_old_style_module:
+        foo: true
+      with_sequence: start=1 end={{end|default(1)}}
+      register: out
+      vars:
+        ansible_bash_interpreter: "/usr/bin/env RUN_VIA_ENV=yes bash"
+
+    - assert:
+        that: |
+          (not out.changed) and
+          (not out.results[0].changed) and
+          out.results[0].msg == 'Here is my input' and
+          out.results[0].run_via_env == "yes"

tests/ansible/lib/modules/custom_bash_old_style_module.sh

@@ -16,5 +16,6 @@ echo "{"
 echo "  \"changed\": false,"
 echo "  \"msg\": \"Here is my input\","
 echo "  \"filename\": \"$INPUT\","
+echo "  \"run_via_env\": \"$RUN_VIA_ENV\","
 echo "  \"input\": [\"$(cat $INPUT | tr \" \' )\"]"
 echo "}"