Allow default section in ini to be specified

The default section in an ini file will always be 'DEFAULT', but for some
configuration files you may want to be able to set this to ensure
another section is at the top. 'global' for example, when working with
fio.

This PR adds the ability to set the section to be at the top, but will
default to 'DEFAULT' so no change will happen to existing tasks running
config_template.

Change-Id: Ifbc0b91aef46f3c2d98e73fdc9ab888244550bab

action/config_template.py

@@ -72,6 +72,7 @@ class MultiKeyDict(dict):
     >>> print(z)
     ... {'a': tuple(['1', '2']), 'c': {'a': 1}, 'b': ['a', 'b', 'c']}
     """
+
     def __setitem__(self, key, value):
         if key in self:
             if isinstance(self[key], tuple):
@@ -134,9 +135,11 @@ class ConfigTemplateParser(ConfigParser.RawConfigParser):
     key = var3
     key = var2
     """
+
     def __init__(self, *args, **kwargs):
         self._comments = {}
         self.ignore_none_type = bool(kwargs.pop('ignore_none_type', True))
+        self.default_section = str(kwargs.pop('default_section', 'DEFAULT'))
         ConfigParser.RawConfigParser.__init__(self, *args, **kwargs)
 
     def _write(self, fp, section, key, item, entry):
@@ -165,28 +168,33 @@ class ConfigTemplateParser(ConfigParser.RawConfigParser):
             self._write(fp, section, key, value, entry)
 
     def write(self, fp):
+        def _do_write(section_name, section, section_bool=False):
+            _write_comments(section_name)
+            fp.write("[%s]\n" % section_name)
+            for key, value in sorted(section.items()):
+                _write_comments(section_name, optname=key)
+                self._write_check(fp, key=key, value=value,
+                                  section=section_bool)
+            else:
+                fp.write("\n")
+
         def _write_comments(section, optname=None):
             comsect = self._comments.get(section, {})
             if optname in comsect:
                 fp.write(''.join(comsect[optname]))
 
+        if self.default_section != 'DEFAULT' and self._sections.get(
+                self.default_section, False):
+            _do_write(self.default_section,
+                      self._sections[self.default_section],
+                      section_bool=True)
+            self._sections.pop(self.default_section)
+
         if self._defaults:
-            _write_comments('DEFAULT')
+            _do_write('DEFAULT', self._defaults)
-            fp.write("[%s]\n" % 'DEFAULT')
-            for key, value in sorted(self._defaults.items()):
-                _write_comments('DEFAULT', optname=key)
-                self._write_check(fp, key=key, value=value)
-            else:
-                fp.write("\n")
 
         for section in sorted(self._sections):
-            _write_comments(section)
+            _do_write(section, self._sections[section], section_bool=True)
-            fp.write("[%s]\n" % section)
-            for key, value in sorted(self._sections[section].items()):
-                _write_comments(section, optname=key)
-                self._write_check(fp, key=key, value=value, section=True)
-            else:
-                fp.write("\n")
 
     def _read(self, fp, fpname):
         comments = []
@@ -293,7 +301,8 @@ class ActionModule(ActionBase):
                                     config_overrides,
                                     resultant,
                                     list_extend=True,
-                                    ignore_none_type=True):
+                                    ignore_none_type=True,
+                                    default_section='DEFAULT'):
         """Returns string value from a modified config file.
 
         :param config_overrides: ``dict``
@@ -307,7 +316,8 @@ class ActionModule(ActionBase):
             config = ConfigTemplateParser(
                 allow_no_value=True,
                 dict_type=MultiKeyDict,
-                ignore_none_type=ignore_none_type
+                ignore_none_type=ignore_none_type,
+                default_section=default_section
             )
             config.optionxform = str
         except Exception:
@@ -376,7 +386,8 @@ class ActionModule(ActionBase):
                                      config_overrides,
                                      resultant,
                                      list_extend=True,
-                                     ignore_none_type=True):
+                                     ignore_none_type=True,
+                                     default_section='DEFAULT'):
         """Returns config json
 
         Its important to note that file ordering will not be preserved as the
@@ -390,7 +401,8 @@ class ActionModule(ActionBase):
         merged_resultant = self._merge_dict(
             base_items=original_resultant,
             new_items=config_overrides,
-            list_extend=list_extend
+            list_extend=list_extend,
+            default_section=default_section
         )
         return json.dumps(
             merged_resultant,
@@ -402,7 +414,8 @@ class ActionModule(ActionBase):
                                      config_overrides,
                                      resultant,
                                      list_extend=True,
-                                     ignore_none_type=True):
+                                     ignore_none_type=True,
+                                     default_section='DEFAULT'):
         """Return config yaml.
 
         :param config_overrides: ``dict``
@@ -537,6 +550,8 @@ class ActionModule(ActionBase):
         # name with out the '=' or ':' suffix. The default is true.
         ignore_none_type = self._task.args.get('ignore_none_type', True)
 
+        default_section = self._task.args.get('default_section', 'DEFAULT')
+
         return True, dict(
             source=source,
             dest=user_dest,
@@ -544,7 +559,8 @@ class ActionModule(ActionBase):
             config_type=config_type,
             searchpath=searchpath,
             list_extend=list_extend,
-            ignore_none_type=ignore_none_type
+            ignore_none_type=ignore_none_type,
+            default_section=default_section
         )
 
     def run(self, tmp=None, task_vars=None):
@@ -618,7 +634,8 @@ class ActionModule(ActionBase):
                 config_overrides=_vars['config_overrides'],
                 resultant=resultant,
                 list_extend=_vars.get('list_extend', True),
-                ignore_none_type=_vars.get('ignore_none_type', True)
+                ignore_none_type=_vars.get('ignore_none_type', True),
+                default_section=_vars.get('default_section', 'DEFAULT')
             )
 
         # Re-template the resultant object as it may have new data within it
@@ -651,6 +668,7 @@ class ActionModule(ActionBase):
         new_module_args.pop('config_type', None)
         new_module_args.pop('list_extend', None)
         new_module_args.pop('ignore_none_type', None)
+        new_module_args.pop('default_section', None)
         # Content from config_template is converted to src
         new_module_args.pop('content', None)
 
@@ -663,7 +681,7 @@ class ActionModule(ActionBase):
         if self._play_context.diff:
             rc['diff'] = []
             rc['diff'].append(self._get_diff_data(_vars['dest'],
-                              transferred_data, task_vars))
+                                                  transferred_data, task_vars))
         if self._task.args.get('content'):
             os.remove(_vars['source'])
         return rc

library/config_template

@@ -58,6 +58,12 @@ options:
     choices:
       - True
       - False
+  default_section:
+    description:
+      - Specify the default section for INI configuration files. This is the
+        section that will appear at the top of the configuration file. For
+        example 'global'.
+    default: 'DEFAULT'
 
 author: Kevin Carter
 """
@@ -68,6 +74,7 @@ EXAMPLES = """
       src: templates/test.ini.j2
       dest: /tmp/test.ini
       config_overrides: {}
+      top_ini_section: 'global'
       config_type: ini
 
   - name: run config template json

releasenotes/notes/top_ini_section-c28d7acadf5fe836.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - Allow the default section in an ini file to be specified
+    using the ``default_section`` variable when calling a
+    ``config_template`` task. This defaults to ``DEFAULT``.

tests/files/test_default_section.ini.expected

@@ -0,0 +1,8 @@
+[global]
+test1 = 1
+test2 = 2
+
+[section1]
+setting1 = 1
+setting2 = 2
+

tests/templates/test_default_section.ini

@@ -0,0 +1,5 @@
+[section1]
+setting1=1
+
+[global]
+test1=1

tests/test.yml

@@ -215,6 +215,21 @@
         - [ 0, 1, 2 ]
         - [ "{{ test_config_ini_overrides }}" ]
 
+    - name: Put down default_section_expected file
+      copy:
+        src: "{{ playbook_dir }}/files/test_default_section.ini.expected"
+        dest: "/tmp/test_default_section.ini"
+
+    - name: Template using default_section
+      config_template:
+        src: "{{ playbook_dir }}/templates/test_default_section.ini"
+        dest: "/tmp/test_default_section.ini"
+        config_type: "ini"
+        config_overrides: "{{ test_default_section_overrides }}"
+        default_section: "global"
+      register: template_changed
+      failed_when: template_changed | changed
+
   vars:
     test_config_ini_overrides:
       DEFAULT:
@@ -259,3 +274,8 @@
         - 4
     test_config_yml_hostvars_overrides:
       test_hostvar: "{{ ansible_default_ipv4.address }}"
+    test_default_section_overrides:
+      global:
+        test2: 2
+      section1:
+        setting2: 2