fix: remove some workaround about ansible 2.8 and update docs

Makefile

@@ -23,10 +23,7 @@ test_install: build
 	@./test_install.sh $(VIRTUALENV_DIR) $(ANSIBLE_VERSION)
 
 test:
-	# Ansible 2.8 CLI sets some global variables causing the tests to fail if the cli tests are run before
-	# the grapher tests. It works in Ansible 2.9. So here we explicitly set the tests order.
-	# TODO: Remove pytest arguments when we drop support for Ansible 2.8
-	cd tests && pytest test_grapher.py test_cli.py test_postprocessor.py
+	cd tests && pytest
 
 clean:
 	@echo "Cleaning..."

README.md

@@ -11,8 +11,8 @@ Inspired by [Ansible Inventory Grapher](https://github.com/willthames/ansible-in
 
 ## Prerequisites
  - Python 3
- - **Ansible** >= 2.8: If you still use an older version of Ansible, create a virtual environment and install ansible-playbook-grapher. 
- **pip will install a version of Ansible >= 2.8 if not already installed.** I try to respect [Red Hat Ansible Engine Life Cycle](https://access.redhat.com/support/policy/updates/ansible-engine) for the supported Ansible version. 
+ - **Ansible** >= 2.9: If you still use an older version of Ansible, create a virtual environment and install ansible-playbook-grapher. 
+ **pip will install a version of Ansible >= 2.9 if not already installed.** I try to respect [Red Hat Ansible Engine Life Cycle](https://access.redhat.com/support/policy/updates/ansible-engine) for the supported Ansible version. 
  - **Graphviz**: The tool used to generate the graph in SVG. 
    ```shell script
    $ sudo apt-get install graphviz # or yum install or brew install

ansibleplaybookgrapher/cli.py

@@ -4,6 +4,7 @@ import sys
 from abc import ABC
 
 from ansible.cli import CLI
+from ansible.cli.arguments import option_helpers
 from ansible.release import __version__ as ansible_version
 from ansible.utils.display import Display
 from packaging import version
@@ -12,7 +13,7 @@ from ansibleplaybookgrapher import __prog__, __version__
 from ansibleplaybookgrapher.grapher import PlaybookGrapher
 from ansibleplaybookgrapher.postprocessor import PostProcessor
 
-# We need to know if we are using ansible 2.8 because the CLI has been refactored in
+# At some time, we needed to know if we are using ansible 2.8 because the CLI has been refactored in this PR:
 # https://github.com/ansible/ansible/pull/50069
 IS_ANSIBLE_2_9_X = version.parse(ansible_version) >= version.parse("2.9")
 
@@ -59,14 +60,14 @@ class GrapherCLI(CLI, ABC):
 
 class PlaybookGrapherCLI(GrapherCLI):
     """
-    The dedicated playbook CLI for Ansible 2.9 and above.
-    Note: Use this class as the main CLI when we drop support for ansible < 2.9
+    The dedicated playbook CLI for Ansible 2.9 and above (for the moment)
     """
 
     def __init__(self, args, callback=None):
         super(PlaybookGrapherCLI, self).__init__(args=args, callback=callback)
-        # we keep the old options as instance attribute for backward compatibility for the grapher
-        # Ansible 2.8 has removed it and use a global context instead
+        # We keep the old options as instance attribute for backward compatibility for the grapher CLI.
+        # From Ansible 2.8, they remove this instance attribute 'options' and use a global context instead.
+        # But this may change in the future: https://github.com/ansible/ansible/blob/bcb64054edaa7cf636bd38b8ab0259f6fb93f3f9/lib/ansible/context.py#L8
         self.options = None
 
     def _add_my_options(self):
@@ -94,18 +95,17 @@ class PlaybookGrapherCLI(GrapherCLI):
 
         self.parser.add_argument('playbook_filename', help='Playbook to graph', metavar='playbook')
 
+        # Use ansible helper to add some default options also
+        option_helpers.add_subset_options(self.parser)
+        option_helpers.add_vault_options(self.parser)
+        option_helpers.add_runtask_options(self.parser)
+
     def init_parser(self, usage="", desc=None, epilog=None):
         super(PlaybookGrapherCLI, self).init_parser(usage="%s [options] playbook.yml" % __prog__,
                                                     desc="Make graphs from your Ansible Playbooks.", epilog=epilog)
 
         self._add_my_options()
 
-        # add ansible specific options
-        from ansible.cli.arguments import option_helpers as opt_help
-        opt_help.add_subset_options(self.parser)
-        opt_help.add_vault_options(self.parser)
-        opt_help.add_runtask_options(self.parser)
-
     def post_process_args(self, options):
         options = super(PlaybookGrapherCLI, self).post_process_args(options)
 

requirements.txt

@@ -1,4 +1,4 @@
-ansible>=2.8.0
+ansible>=2.9.0
 graphviz<1
 colour<1
 lxml<5