Define ANSIBLE_HOME to isolate from user environment

.vscode/settings.json

@@ -10,7 +10,7 @@
       "source.fixAll": "explicit",
       "source.organizeImports": "explicit"
     },
-    "editor.defaultFormatter": "ms-python.black-formatter",
+    "editor.defaultFormatter": "charliermarsh.ruff",
     "editor.formatOnSave": true
   },
   "editor.formatOnSave": true,

src/ansible_compat/prerun.py

@@ -1,22 +1,32 @@
 """Utilities for configuring ansible runtime environment."""
 
-import hashlib
 import os
+import warnings
 from pathlib import Path
 
 
 def get_cache_dir(project_dir: Path) -> Path:
-    """Compute cache directory to be used based on project path."""
-    # we only use the basename instead of the full path in order to ensure that
-    # we would use the same key regardless the location of the user home
-    # directory or where the project is clones (as long the project folder uses
-    # the same name).
-    basename = project_dir.resolve().name.encode(encoding="utf-8")
-    # 6 chars of entropy should be enough
-    cache_key = hashlib.sha256(basename).hexdigest()[:6]
-    cache_dir = (
-        Path(os.getenv("XDG_CACHE_HOME", "~/.cache")).expanduser()
-        / "ansible-compat"
-        / cache_key
-    )
+    """Compute cache directory to be used based on project path.
+
+    If isolated=True, it will ensure ANSIBLE_HOME is defined.
+    """
+    ansible_home: Path
+    if "ANSIBLE_HOME" in os.environ:
+        cache_dir = Path(os.environ["ANSIBLE_HOME"])
+        ansible_home = cache_dir
+    elif "VIRTUAL_ENV" in os.environ:
+        cache_dir = Path(os.environ["VIRTUAL_ENV"]) / ".ansible"
+        ansible_home = cache_dir
+        msg = f"ANSIBLE_HOME is not set, will will define it to {ansible_home} to ensure test isolation."
+        warnings.warn(msg, stacklevel=1)
+        os.environ["ANSIBLE_HOME"] = ansible_home.as_posix()
+    else:
+        cache_dir = Path("~/.ansible").expanduser() / ".ansible"
+        ansible_home = cache_dir
+
+    # create expected directory structure in order to avoid possible warnings
+    # or errors from ansible (ansible-galaxy in particular)
+    for subdir in ("roles",):
+        (Path(ansible_home) / subdir).mkdir(parents=True, exist_ok=True)
+
     return cache_dir

src/ansible_compat/runtime.py

@@ -208,8 +208,8 @@ def __init__(
         if "PYTHONWARNINGS" not in self.environ:  # pragma: no cover
             self.environ["PYTHONWARNINGS"] = "ignore:Blowfish has been deprecated"
 
-        if isolated:
-            self.cache_dir = get_cache_dir(self.project_dir)
+        self.cache_dir = get_cache_dir(self.project_dir)
+
         self.config = AnsibleConfig(cache_dir=self.cache_dir)
 
         # Add the sys.path to the collection paths if not isolated

test/test_runtime.py

@@ -143,6 +143,7 @@ def test_runtime_prepare_ansible_paths_validation() -> None:
         runtime._prepare_ansible_paths()
 
 
+@pytest.mark.filterwarnings("ignore::UserWarning")
 @pytest.mark.parametrize(
     ("folder", "role_name", "isolated"),
     (
@@ -652,10 +653,10 @@ def test_upgrade_collection(runtime_tmp: Runtime) -> None:
     runtime_tmp.require_collection("community.molecule", "0.1.0")
 
 
-def test_require_collection_no_cache_dir() -> None:
+@pytest.mark.filterwarnings("ignore::UserWarning")
+def test_require_collection_not_isolated() -> None:
     """Check require_collection without a cache directory."""
-    runtime = Runtime()
-    assert not runtime.cache_dir
+    runtime = Runtime(isolated=False)
     runtime.require_collection("community.molecule", "0.1.0", install=True)
 
 
@@ -1018,10 +1019,16 @@ def test_get_galaxy_role_name_invalid() -> None:
     assert _get_galaxy_role_name(galaxy_infos) == ""
 
 
+@pytest.mark.filterwarnings("ignore::UserWarning")
 def test_runtime_has_playbook() -> None:
     """Tests has_playbook method."""
     runtime = Runtime(require_module=True)
 
+    runtime.prepare_environment(
+        required_collections={"community.molecule": "0.1.0"},
+        install_local=True,
+    )
+
     assert not runtime.has_playbook("this-does-not-exist.yml")
     # call twice to ensure cache is used:
     assert not runtime.has_playbook("this-does-not-exist.yml")