Implement file locking on cache directory

This change should prevent concurrency problems related to use of
the cache directory.

.pre-commit-config.yaml

@@ -131,6 +131,7 @@ repos:
           - ansible-compat>=2.2.0
           - ansible-core
           - enrich
+          - filelock
           - flaky
           - pytest
           - rich>=11.0.0
@@ -157,6 +158,7 @@ repos:
           - ansible-core
           - docutils
           - enrich
+          - filelock
           - flaky
           - jsonschema>=4.9.0
           - pytest

requirements.txt

@@ -18,21 +18,22 @@ cffi==1.15.1
 charset-normalizer==2.1.0
 click==8.1.3
 commonmark==0.9.1
-coverage==6.4.2
+coverage==6.4.3
 cryptography==37.0.4
 dill==0.3.5.1
 docutils==0.16
 enrich==1.2.7
 execnet==1.9.0
-flake8==5.0.2
+filelock==3.7.1
+flake8==5.0.4
 flaky==3.7.0
 idna==3.3
 imagesize==1.4.1
 importlib-metadata==4.12.0
 iniconfig==1.1.1
 isort==5.10.1
 jinja2==3.1.2
-jsonschema==4.9.0
+jsonschema==4.9.1
 lazy-object-proxy==1.7.1
 markdown-it-py==2.1.0
 markupsafe==2.1.1
@@ -51,7 +52,7 @@ platformdirs==2.5.2
 pluggy==1.0.0
 psutil==5.9.1
 py==1.11.0
-pycodestyle==2.9.0
+pycodestyle==2.9.1
 pycparser==2.21
 pyflakes==2.5.0
 pygments==2.12.0
@@ -84,7 +85,7 @@ sphinxcontrib-qthelp==1.0.3
 sphinxcontrib-serializinghtml==1.1.5
 subprocess-tee==0.3.5
 tomli==2.0.1
-tomlkit==0.11.1
+tomlkit==0.11.2
 typing-extensions==4.3.0
 urllib3==1.26.11
 wcmatch==8.4

setup.cfg

@@ -70,6 +70,7 @@ install_requires =
   ansible-compat>=2.2.0  # GPLv3
   ansible-core>=2.12.0  # GPLv3
   enrich>=1.2.6
+  filelock  # The Unlicense
   jsonschema>=4.9.0  # MIT, version needed for improved errors
   packaging
   pyyaml

src/ansiblelint/__main__.py

@@ -33,6 +33,7 @@
 from ansible_compat.config import ansible_version
 from ansible_compat.prerun import get_cache_dir
 from enrich.console import should_do_markup
+from filelock import FileLock
 
 from ansiblelint import cli
 from ansiblelint._mockings import _perform_mockings_cleanup
@@ -104,6 +105,10 @@ def initialize_options(arguments: Optional[List[str]] = None) -> None:
     options.configured = True
     options.cache_dir = get_cache_dir(options.project_dir)
 
+    # add a lock file so we do not have two instances running inside at the same time
+    options.cache_dir_lock = FileLock(f"{options.cache_dir}/.lock")
+    options.cache_dir_lock.acquire()
+
 
 def _do_list(rules: "RulesCollection") -> int:
     # On purpose lazy-imports to avoid pre-loading Ansible
@@ -228,6 +233,8 @@ def main(argv: Optional[List[str]] = None) -> int:  # noqa: C901
     app.render_matches(result.matches)
 
     _perform_mockings_cleanup()
+    options.cache_dir_lock.release()
+    os.unlink(options.cache_dir_lock.lock_file)
 
     return app.report_outcome(result, mark_as_success=mark_as_success)